Oxidative Stress
Antioxidants
Reactive Oxygen Species
Hydrogen Peroxide
Lipid Peroxidation
Superoxide Dismutase
Glutathione
Oxidants
Catalase
Thiobarbituric Acid Reactive Substances
Protein Carbonylation
Oxidation-Reduction
Glutathione Peroxidase
F2-Isoprostanes
Paraquat
Acetylcysteine
tert-Butylhydroperoxide
Glutathione Disulfide
Mitochondria
NF-E2-Related Factor 2
Ascorbic Acid
NADPH Oxidase
Isoprostanes
Free Radical Scavengers
Superoxides
Apoptosis
Biological Markers
Cells, Cultured
Rats, Wistar
Vitamin E
Cell Survival
Heme Oxygenase-1
Disease Models, Animal
Vitamin K 3
Peroxiredoxins
Glutathione Reductase
Rats, Sprague-Dawley
Lipid Peroxides
DNA Damage
Inflammation
Free Radicals
Nitric Oxide
Signal Transduction
Diamide
Thioredoxins
Buthionine Sulfoximine
Cytoprotection
Mice, Inbred C57BL
Cell Death
Blotting, Western
Dinoprost
Aging
Liver
Peroxides
Dose-Response Relationship, Drug
Reactive Nitrogen Species
Plant Extracts
Membrane Potential, Mitochondrial
Mice, Knockout
alpha-Tocopherol
Iron
RNA, Messenger
Endothelium, Vascular
Thioctic Acid
Glutamate-Cysteine Ligase
Gene Expression Regulation
Xanthine Oxidase
Diabetes Mellitus, Experimental
Acetophenones
Oxygen
Heme Oxygenase (Decyclizing)
Peroxidases
Up-Regulation
Spin Labels
Reverse Transcriptase Polymerase Chain Reaction
Protective Agents
Kidney
Glutathione Transferase
Mutation
Peroxynitrous Acid
Enzyme Activation
Stress, Physiological
Models, Biological
Oxidoreductases
Aconitate Hydratase
Caspase 3
Enzyme Inhibitors
Neuroprotective Agents
Myocardium
Metalloporphyrins
Dietary Supplements
Gene Expression Profiling
NF-kappa B
Gene Expression
Neurons
Cytochrome P-450 CYP2E1
Gene Expression Regulation, Enzymologic
Tyrosine
Peroxiredoxin III
Nitric Oxide Synthase Type III
Aryldialkylphosphatase
Retinal Pigment Epithelium
Cell Aging
Phosphorylation
Benzene Derivatives
Endothelial Cells
Glutaredoxins
Glucose
Gene Expression Regulation, Bacterial
Molecular Sequence Data
Brain
Analysis of Variance
Ubiquinone
Herbicides
Thioredoxin-Disulfide Reductase
Reperfusion Injury
Nitrates
Immunohistochemistry
Case-Control Studies
Peroxiredoxin VI
Glycosylation End Products, Advanced
Comet Assay
Ethanol
Lung
Mitochondrial Proteins
Methionine Sulfoxide Reductases
Maleates
Transcription Factors
Erythrocytes
NAD(P)H Dehydrogenase (Quinone)
Homeostasis
Peroxidase
Nitric Oxide Synthase Type II
Nitrites
L-Lactate Dehydrogenase
Oligonucleotide Array Sequence Analysis
Heat-Shock Response
Mice, Transgenic
Random Allocation
Glucosephosphate Dehydrogenase
Gene Deletion
Quercetin
Diquat
Fibroblasts
Transcription, Genetic
Electrophoresis, Gel, Two-Dimensional
DNA, Mitochondrial
In Situ Nick-End Labeling
Hepatocytes
Advanced Oxidation Protein Products
Streptozocin
Autophagy
Gene Expression Regulation, Fungal
Myocytes, Cardiac
Epithelial Cells
Adaptation, Physiological
RNA, Small Interfering
Vasodilation
Xanthine
Atherosclerosis
p38 Mitogen-Activated Protein Kinases
Nitrilotriacetic Acid
Metallothionein
Glucose Oxidase
Hormesis
Tumor Necrosis Factor-alpha
DNA Fragmentation
Lens, Crystalline
Hypertension
Body Weight
Nerve Degeneration
Neurodegenerative Diseases
Cell Respiration
Daunorubicin-induced apoptosis in rat cardiac myocytes is inhibited by dexrazoxane. (1/22885)
-The clinical efficacy of anthracycline antineoplastic agents is limited by a high incidence of severe and usually irreversible cardiac toxicity, the cause of which remains controversial. In primary cultures of neonatal and adult rat ventricular myocytes, we found that daunorubicin, at concentrations /=10 micromol/L induced necrotic cell death within 24 hours, with no changes characteristic of apoptosis. To determine whether reactive oxygen species play a role in daunorubicin-mediated apoptosis, we monitored the generation of hydrogen peroxide with dichlorofluorescein (DCF). However, daunorubicin (1 micromol/L) did not increase DCF fluorescence, nor were the antioxidants N-acetylcysteine or the combination of alpha-tocopherol and ascorbic acid able to prevent apoptosis. In contrast, dexrazoxane (10 micromol/L), known clinically to limit anthracycline cardiac toxicity, prevented daunorubicin-induced myocyte apoptosis, but not necrosis induced by higher anthracycline concentrations (>/=10 micromol/L). The antiapoptotic action of dexrazoxane was mimicked by the superoxide-dismutase mimetic porphyrin manganese(II/III)tetrakis(1-methyl-4-peridyl)porphyrin (50 micromol/L). The recognition that anthracycline-induced cardiac myocyte apoptosis, perhaps mediated by superoxide anion generation, occurs at concentrations well below those that result in myocyte necrosis, may aid in the design of new therapeutic strategies to limit the toxicity of these drugs. (+info)Base excision repair of oxidative DNA damage activated by XPG protein. (2/22885)
Oxidized pyrimidines in DNA are removed by a distinct base excision repair pathway initiated by the DNA glycosylase--AP lyase hNth1 in human cells. We have reconstituted this single-residue replacement pathway with recombinant proteins, including the AP endonuclease HAP1/APE, DNA polymerase beta, and DNA ligase III-XRCC1 heterodimer. With these proteins, the nucleotide excision repair enzyme XPG serves as a cofactor for the efficient function of hNth1. XPG protein promotes binding of hNth1 to damaged DNA. The stimulation of hNth1 activity is retained in XPG catalytic site mutants inactive in nucleotide excision repair. The data support the model that development of Cockayne syndrome in XP-G patients is related to inefficient excision of endogenous oxidative DNA damage. (+info)Chaperone activity with a redox switch. (3/22885)
Hsp33, a member of a newly discovered heat shock protein family, was found to be a very potent molecular chaperone. Hsp33 is distinguished from all other known molecular chaperones by its mode of functional regulation. Its activity is redox regulated. Hsp33 is a cytoplasmically localized protein with highly reactive cysteines that respond quickly to changes in the redox environment. Oxidizing conditions like H2O2 cause disulfide bonds to form in Hsp33, a process that leads to the activation of its chaperone function. In vitro and in vivo experiments suggest that Hsp33 protects cells from oxidants, leading us to conclude that we have found a protein family that plays an important role in the bacterial defense system toward oxidative stress. (+info)The Golgi apparatus plays a significant role in the maintenance of Ca2+ homeostasis in the vps33Delta vacuolar biogenesis mutant of Saccharomyces cerevisiae. (4/22885)
The vacuole is the major site of intracellular Ca2+ storage in yeast and functions to maintain cytosolic Ca2+ levels within a narrow physiological range. In this study, we examined how cellular Ca2+ homeostasis is maintained in a vps33Delta vacuolar biogenesis mutant. We found that growth of the vps33Delta strain was sensitive to high or low extracellular Ca2+. This strain could not properly regulate cytosolic Ca2+ levels and was able to retain only a small fraction of its total cellular Ca2+ in a nonexchangeable intracellular pool. Surprisingly, the vps33Delta strain contained more total cellular Ca2+ than the wild type strain. Because most cellular Ca2+ is normally found within the vacuole, this suggested that other intracellular compartments compensated for the reduced capacity to store Ca2+ within the vacuole of this strain. To test this hypothesis, we examined the contribution of the Golgi-localized Ca2+ ATPase Pmr1p in the maintenance of cellular Ca2+ homeostasis. We found that a vps33Delta/pmr1Delta strain was hypersensitive to high extracellular Ca2+. In addition, certain combinations of mutations effecting both vacuolar and Golgi Ca2+ transport resulted in synthetic lethality. These results indicate that the Golgi apparatus plays a significant role in maintaining Ca2+ homeostasis when vacuolar biogenesis is compromised. (+info)Characterization of transgenic mice with targeted disruption of the catalytic domain of the double-stranded RNA-dependent protein kinase, PKR. (5/22885)
The interferon-inducible, double-stranded RNA-dependent protein kinase PKR has been implicated in anti-viral, anti-tumor, and apoptotic responses. Others have attempted to examine the requirement of PKR in these roles by targeted disruption at the amino terminal-encoding region of the Pkr gene. By using a strategy that aims at disruption of the catalytic domain of PKR, we have generated mice that are genetically ablated for functional PKR. Similar to the other mouse model of Pkr disruption, we have observed no consequences of loss of PKR on tumor suppression. Anti-viral response to influenza and vaccinia also appeared to be normal in mice and in cells lacking PKR. Cytokine signaling in the type I interferon pathway is normal but may be compromised in the erythropoietin pathway in erythroid bone marrow precursors. Contrary to the amino-terminal targeted Pkr mouse, tumor necrosis factor alpha-induced apoptosis and the anti-viral apoptosis response to influenza is not impaired in catalytic domain-targeted Pkr-null cells. The observation of intact eukaryotic initiation factor-2alpha phosphorylation in these Pkr-null cells provides proof of rescue by another eukaryotic initiation factor-2alpha kinase(s). (+info)Increased lipophilicity and subsequent cell partitioning decrease passive transcellular diffusion of novel, highly lipophilic antioxidants. (6/22885)
Oxidative stress is considered a cause or propagator of acute and chronic disorders of the central nervous system. Novel 2, 4-diamino-pyrrolo[2,3-d]pyrimidines are potent inhibitors of iron-dependent lipid peroxidation, are cytoprotective in cell culture models of oxidative injury, and are neuroprotective in brain injury and ischemia models. The selection of lead candidates from this series required that they reach target cells deep within brain tissue in efficacious amounts after oral dosing. A homologous series of 26 highly lipophilic pyrrolopyrimidines was examined using cultured cell monolayers to understand the structure-permeability relationship and to use this information to predict brain penetration and residence time. Pyrrolopyrimidines were shown to be a more permeable structural class of membrane-interactive antioxidants where transepithelial permeability was inversely related to lipophilicity or to cell partitioning. Pyrrole substitutions influence cell partitioning where bulky hydrophobic groups increased partitioning and decreased permeability and smaller hydrophobic groups and more hydrophilic groups, especially those capable of weak hydrogen bonding, decreased partitioning, and increased permeability. Transmonolayer diffusion for these membrane-interactive antioxidants was limited mostly by desorption from the receiver-side membrane into the buffer. Thus, in this case, these in vitro cell monolayer models do not adequately mimic the in vivo situation by underestimating in vivo bioavailability of highly lipophilic compounds unless acceptors, such as serum proteins, are added to the receiving buffer. (+info)Inactivation of both RNA binding and aconitase activities of iron regulatory protein-1 by quinone-induced oxidative stress. (7/22885)
Iron regulatory protein-1 (IRP-1) controls the expression of several mRNAs by binding to iron-responsive elements (IREs) in their untranslated regions. In iron-replete cells, a 4Fe-4S cluster converts IRP-1 to cytoplasmic aconitase. IRE binding activity is restored by cluster loss in response to iron starvation, NO, or extracellular H2O2. Here, we study the effects of intracellular quinone-induced oxidative stress on IRP-1. Treatment of murine B6 fibroblasts with menadione sodium bisulfite (MSB), a redox cycling drug, causes a modest activation of IRP-1 to bind to IREs within 15-30 min. However, IRE binding drops to basal levels within 60 min. Surprisingly, a remarkable loss of both IRE binding and aconitase activities of IRP-1 follows treatment with MSB for 1-2 h. These effects do not result from alterations in IRP-1 half-life, can be antagonized by the antioxidant N-acetylcysteine, and regulate IRE-containing mRNAs; the capacity of iron-starved MSB-treated cells to increase transferrin receptor mRNA levels is inhibited, and MSB increases the translation of a human growth hormone indicator mRNA bearing an IRE in its 5'-untranslated region. Nonetheless, MSB inhibits ferritin synthesis. Thus, menadione-induced oxidative stress leads to post-translational inactivation of both genetic and enzymatic functions of IRP-1 by a mechanism that lies beyond the "classical" Fe-S cluster switch and exerts multiple effects on cellular iron metabolism. (+info)Identification and functional characterization of a novel mitochondrial thioredoxin system in Saccharomyces cerevisiae. (8/22885)
The so-called thioredoxin system, thioredoxin (Trx), thioredoxin reductase (Trr), and NADPH, acts as a disulfide reductase system and can protect cells against oxidative stress. In Saccharomyces cerevisiae, two thioredoxins (Trx1 and Trx2) and one thioredoxin reductase (Trr1) have been characterized, all of them located in the cytoplasm. We have identified and characterized a novel thioredoxin system in S. cerevisiae. The TRX3 gene codes for a 14-kDa protein containing the characteristic thioredoxin active site (WCGPC). The TRR2 gene codes for a protein of 37 kDa with the active-site motif (CAVC) present in prokaryotic thioredoxin reductases and binding sites for NADPH and FAD. We cloned and expressed both proteins in Escherichia coli, and the recombinant Trx3 and Trr2 proteins were active in the insulin reduction assay. Trx3 and Trr2 proteins have N-terminal domain extensions with characteristics of signals for import into mitochondria. By immunoblotting analysis of Saccharomyces subcellular fractions, we provide evidence that these proteins are located in mitochondria. We have also constructed S. cerevisiae strains null in Trx3 and Trr2 proteins and tested them for sensitivity to hydrogen peroxide. The Deltatrr2 mutant was more sensitive to H2O2, whereas the Deltatrx3 mutant was as sensitive as the wild type. These results suggest an important role of the mitochondrial thioredoxin reductase in protection against oxidative stress in S. cerevisiae. (+info)Oxidative stress is defined as an imbalance between the production of reactive oxygen species (free radicals) and the body's ability to detoxify them or repair the damage they cause. This imbalance can lead to cellular damage, oxidation of proteins, lipids, and DNA, disruption of cellular functions, and activation of inflammatory responses. Prolonged or excessive oxidative stress has been linked to various health conditions, including cancer, cardiovascular diseases, neurodegenerative disorders, and aging-related diseases.
Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, which are unstable molecules that the body produces as a reaction to environmental and other pressures. Antioxidants are able to neutralize free radicals by donating an electron to them, thus stabilizing them and preventing them from causing further damage to the cells.
Antioxidants can be found in a variety of foods, including fruits, vegetables, nuts, and grains. Some common antioxidants include vitamins C and E, beta-carotene, and selenium. Antioxidants are also available as dietary supplements.
In addition to their role in protecting cells from damage, antioxidants have been studied for their potential to prevent or treat a number of health conditions, including cancer, heart disease, and age-related macular degeneration. However, more research is needed to fully understand the potential benefits and risks of using antioxidant supplements.
Reactive Oxygen Species (ROS) are highly reactive molecules containing oxygen, including peroxides, superoxide, hydroxyl radical, and singlet oxygen. They are naturally produced as byproducts of normal cellular metabolism in the mitochondria, and can also be generated by external sources such as ionizing radiation, tobacco smoke, and air pollutants. At low or moderate concentrations, ROS play important roles in cell signaling and homeostasis, but at high concentrations, they can cause significant damage to cell structures, including lipids, proteins, and DNA, leading to oxidative stress and potential cell death.
Hydrogen peroxide (H2O2) is a colorless, odorless, clear liquid with a slightly sweet taste, although drinking it is harmful and can cause poisoning. It is a weak oxidizing agent and is used as an antiseptic and a bleaching agent. In diluted form, it is used to disinfect wounds and kill bacteria and viruses on the skin; in higher concentrations, it can be used to bleach hair or remove stains from clothing. It is also used as a propellant in rocketry and in certain industrial processes. Chemically, hydrogen peroxide is composed of two hydrogen atoms and two oxygen atoms, and it is structurally similar to water (H2O), with an extra oxygen atom. This gives it its oxidizing properties, as the additional oxygen can be released and used to react with other substances.
Lipid peroxidation is a process in which free radicals, such as reactive oxygen species (ROS), steal electrons from lipids containing carbon-carbon double bonds, particularly polyunsaturated fatty acids (PUFAs). This results in the formation of lipid hydroperoxides, which can decompose to form a variety of compounds including reactive carbonyl compounds, aldehydes, and ketones.
Malondialdehyde (MDA) is one such compound that is commonly used as a marker for lipid peroxidation. Lipid peroxidation can cause damage to cell membranes, leading to changes in their fluidity and permeability, and can also result in the modification of proteins and DNA, contributing to cellular dysfunction and ultimately cell death. It is associated with various pathological conditions such as atherosclerosis, neurodegenerative diseases, and cancer.
Medical Definition:
Superoxide dismutase (SOD) is an enzyme that catalyzes the dismutation of superoxide radicals (O2-) into oxygen (O2) and hydrogen peroxide (H2O2). This essential antioxidant defense mechanism helps protect the body's cells from damage caused by reactive oxygen species (ROS), which are produced during normal metabolic processes and can lead to oxidative stress when their levels become too high.
There are three main types of superoxide dismutase found in different cellular locations:
1. Copper-zinc superoxide dismutase (CuZnSOD or SOD1) - Present mainly in the cytoplasm of cells.
2. Manganese superoxide dismutase (MnSOD or SOD2) - Located within the mitochondrial matrix.
3. Extracellular superoxide dismutase (EcSOD or SOD3) - Found in the extracellular spaces, such as blood vessels and connective tissues.
Imbalances in SOD levels or activity have been linked to various pathological conditions, including neurodegenerative diseases, cancer, and aging-related disorders.
Glutathione is a tripeptide composed of three amino acids: cysteine, glutamic acid, and glycine. It is a vital antioxidant that plays an essential role in maintaining cellular health and function. Glutathione helps protect cells from oxidative stress by neutralizing free radicals, which are unstable molecules that can damage cells and contribute to aging and diseases such as cancer, heart disease, and dementia. It also supports the immune system, detoxifies harmful substances, and regulates various cellular processes, including DNA synthesis and repair.
Glutathione is found in every cell of the body, with particularly high concentrations in the liver, lungs, and eyes. The body can produce its own glutathione, but levels may decline with age, illness, or exposure to toxins. As such, maintaining optimal glutathione levels through diet, supplementation, or other means is essential for overall health and well-being.
Malondialdehyde (MDA) is a naturally occurring organic compound that is formed as a byproduct of lipid peroxidation, a process in which free radicals or reactive oxygen species react with polyunsaturated fatty acids. MDA is a highly reactive aldehyde that can modify proteins, DNA, and other biomolecules, leading to cellular damage and dysfunction. It is often used as a marker of oxidative stress in biological systems and has been implicated in the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders.
Medical definitions of "oxidants" refer to them as oxidizing agents or substances that can gain electrons and be reduced. They are capable of accepting electrons from other molecules in chemical reactions, leading to the production of oxidation products. In biological systems, oxidants play a crucial role in various cellular processes such as energy production and immune responses. However, an imbalance between oxidant and antioxidant levels can lead to a state of oxidative stress, which has been linked to several diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Examples of oxidants include reactive oxygen species (ROS), such as superoxide anion, hydrogen peroxide, and hydroxyl radical, as well as reactive nitrogen species (RNS), such as nitric oxide and peroxynitrite.
Catalase is a type of enzyme that is found in many living organisms, including humans. Its primary function is to catalyze the decomposition of hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). This reaction helps protect cells from the harmful effects of hydrogen peroxide, which can be toxic at high concentrations.
The chemical reaction catalyzed by catalase can be represented as follows:
H2O2 + Catalase → H2O + O2 + Catalase
Catalase is a powerful antioxidant enzyme that plays an important role in protecting cells from oxidative damage. It is found in high concentrations in tissues that produce or are exposed to hydrogen peroxide, such as the liver, kidneys, and erythrocytes (red blood cells).
Deficiency in catalase activity has been linked to several diseases, including cancer, neurodegenerative disorders, and aging. On the other hand, overexpression of catalase has been shown to have potential therapeutic benefits in various disease models, such as reducing inflammation and oxidative stress.
Thiobarbituric acid reactive substances (TBARS) is not a medical term per se, but rather a method used to measure lipid peroxidation in biological samples. Lipid peroxidation is a process by which free radicals steal electrons from lipids, leading to cellular damage and potential disease progression.
The TBARS assay measures the amount of malondialdehyde (MDA), a byproduct of lipid peroxidation, that reacts with thiobarbituric acid (TBA) to produce a pink-colored complex. The concentration of this complex is then measured and used as an indicator of lipid peroxidation in the sample.
While TBARS has been widely used as a measure of oxidative stress, it has limitations, including potential interference from other compounds that can react with TBA and produce similar-colored complexes. Therefore, more specific and sensitive methods for measuring lipid peroxidation have since been developed.
Protein carbonylation is a post-translational modification of proteins, which involves the introduction of carbonyl groups (-CO) into amino acid side chains. This process can occur as a result of various reactive oxygen species (ROS) and oxidative stress, leading to the formation of protein adducts that can alter protein structure and function. Carbonylation can also be induced by advanced glycation end-products (AGEs), which are formed during non-enzymatic glycation reactions between reducing sugars and proteins. Protein carbonylation is often associated with aging, neurodegenerative diseases, and other pathological conditions characterized by oxidative stress and protein misfolding.
Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."
In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).
The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.
Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.
Glutathione peroxidase (GPx) is a family of enzymes with peroxidase activity whose main function is to protect the organism from oxidative damage. They catalyze the reduction of hydrogen peroxide, lipid peroxides, and organic hydroperoxides to water or corresponding alcohols, using glutathione (GSH) as a reducing agent, which is converted to its oxidized form (GSSG). There are several isoforms of GPx found in different tissues, including GPx1 (also known as cellular GPx), GPx2 (gastrointestinal GPx), GPx3 (plasma GPx), GPx4 (also known as phospholipid hydroperoxide GPx), and GPx5-GPx8. These enzymes play crucial roles in various biological processes, such as antioxidant defense, cell signaling, and apoptosis regulation.
F2-isoprostanes are a type of prostaglandin-like compound that is formed in the body through the free radical-catalyzed peroxidation of arachidonic acid, a polyunsaturated fatty acid found in cell membranes. They are produced in response to oxidative stress and are often used as a biomarker for lipid peroxidation and oxidative damage in various diseases, including atherosclerosis, cancer, and neurodegenerative disorders. F2-isoprostanes are chemically stable and can be measured in biological fluids such as blood, urine, and breath condensate. They have been shown to cause vasoconstriction, platelet aggregation, and inflammation, which may contribute to the pathogenesis of various diseases.
Paraquat is a highly toxic herbicide that is used for controlling weeds and grasses in agricultural settings. It is a non-selective contact weed killer, meaning it kills any green plant it comes into contact with. Paraquat is a fast-acting chemical that causes rapid desiccation of plant tissues upon contact.
In a medical context, paraquat is classified as a toxicological emergency and can cause severe poisoning in humans if ingested, inhaled, or comes into contact with the skin or eyes. Paraquat poisoning can lead to multiple organ failure, including the lungs, kidneys, and liver, and can be fatal in severe cases. There is no specific antidote for paraquat poisoning, and treatment typically focuses on supportive care and managing symptoms.
It's important to note that paraquat is highly regulated and its use is restricted to licensed professionals due to its high toxicity. Proper protective equipment, including gloves, goggles, and respiratory protection, should be used when handling paraquat to minimize the risk of exposure.
Deoxyguanosine is a chemical compound that is a component of DNA (deoxyribonucleic acid), one of the nucleic acids. It is a nucleoside, which is a molecule consisting of a sugar (in this case, deoxyribose) and a nitrogenous base (in this case, guanine). Deoxyguanosine plays a crucial role in the structure and function of DNA, as it pairs with deoxycytidine through hydrogen bonding to form a rung in the DNA double helix. It is involved in the storage and transmission of genetic information.
Acetylcysteine is a medication that is used for its antioxidant effects and to help loosen thick mucus in the lungs. It is commonly used to treat conditions such as chronic bronchitis, emphysema, and cystic fibrosis. Acetylcysteine is also known by the brand names Mucomyst and Accolate. It works by thinning and breaking down mucus in the airways, making it easier to cough up and clear the airways. Additionally, acetylcysteine is an antioxidant that helps to protect cells from damage caused by free radicals. It is available as a oral tablet, liquid, or inhaled medication.
Aldehydes are a class of organic compounds characterized by the presence of a functional group consisting of a carbon atom bonded to a hydrogen atom and a double bonded oxygen atom, also known as a formyl or aldehyde group. The general chemical structure of an aldehyde is R-CHO, where R represents a hydrocarbon chain.
Aldehydes are important in biochemistry and medicine as they are involved in various metabolic processes and are found in many biological molecules. For example, glucose is converted to pyruvate through a series of reactions that involve aldehyde intermediates. Additionally, some aldehydes have been identified as toxicants or environmental pollutants, such as formaldehyde, which is a known carcinogen and respiratory irritant.
Formaldehyde is also commonly used in medical and laboratory settings for its disinfectant properties and as a fixative for tissue samples. However, exposure to high levels of formaldehyde can be harmful to human health, causing symptoms such as coughing, wheezing, and irritation of the eyes, nose, and throat. Therefore, appropriate safety measures must be taken when handling aldehydes in medical and laboratory settings.
Tert-butylhydroperoxide (t-BuOOH) is not typically considered a medical term, but rather a chemical compound. It is used in some medical and laboratory contexts. Here's a definition:
Tert-butylhydroperoxide (t-BuOOH) is an organic peroxide with the formula (CH3)3COOH. It is a colorless liquid, commercially available in concentrations up to 70%. It is used as an initiator in chemical reactions, a source of hydroxyl radicals in free-radical chemistry, and as a reagent in organic synthesis. Its use in medical contexts is typically limited to laboratory research and not as a therapeutic agent.
Handling tert-butylhydroperoxide requires caution due to its potential to cause fires and explosions when it comes into contact with certain substances, especially reducing agents and strong acids. Always follow safety guidelines and use appropriate personal protective equipment when handling this compound.
Glutathione disulfide (GSSG) is the oxidized form of glutathione (GSH), which is a tripeptide composed of three amino acids: cysteine, glutamic acid, and glycine. It plays a crucial role in maintaining cellular redox homeostasis by scavenging free radicals and reactive oxygen species (ROS) in the body.
Glutathione exists in two forms - reduced (GSH) and oxidized (GSSG). In the reduced form, glutathione has a sulfhydryl group (-SH), which can donate an electron to neutralize free radicals and ROS. When glutathione donates an electron, it becomes oxidized and forms glutathione disulfide (GSSG).
Glutathione disulfide is a dimer of two glutathione molecules linked by a disulfide bond (-S-S-) between the sulfur atoms of their cysteine residues. The body can recycle GSSG back to its reduced form (GSH) through the action of an enzyme called glutathione reductase, which requires NADPH as a reducing agent.
Maintaining a proper balance between GSH and GSSG is essential for cellular health, as it helps regulate various physiological processes such as DNA synthesis, gene expression, immune function, and apoptosis (programmed cell death). An imbalance in glutathione homeostasis can lead to oxidative stress, inflammation, and the development of various diseases.
Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).
Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.
Nuclear factor erythroid-derived 2-like 2 (NFE2L2), also known as NF-E2-related factor 2 (NRF2), is a protein that plays a crucial role in the regulation of cellular responses to oxidative stress and electrophilic substances. It is a transcription factor that binds to the antioxidant response element (ARE) in the promoter region of various genes, inducing their expression and promoting cellular defense against harmful stimuli.
Under normal conditions, NRF2 is bound to its inhibitor, Kelch-like ECH-associated protein 1 (KEAP1), in the cytoplasm, where it is targeted for degradation by the proteasome. However, upon exposure to oxidative stress or electrophilic substances, KEAP1 undergoes conformational changes, leading to the release and stabilization of NRF2. Subsequently, NRF2 translocates to the nucleus, forms a complex with small Maf proteins, and binds to AREs, inducing the expression of genes involved in antioxidant response, detoxification, and cellular protection.
Genetic variations or dysregulation of the NFE2L2/KEAP1 pathway have been implicated in several diseases, including cancer, neurodegenerative disorders, and pulmonary fibrosis, highlighting its importance in maintaining cellular homeostasis and preventing disease progression.
Ascorbic acid is the chemical name for Vitamin C. It is a water-soluble vitamin that is essential for human health. Ascorbic acid is required for the synthesis of collagen, a protein that plays a role in the structure of bones, tendons, ligaments, and blood vessels. It also functions as an antioxidant, helping to protect cells from damage caused by free radicals.
Ascorbic acid cannot be produced by the human body and must be obtained through diet or supplementation. Good food sources of vitamin C include citrus fruits, strawberries, bell peppers, broccoli, and spinach.
In the medical field, ascorbic acid is used to treat or prevent vitamin C deficiency and related conditions, such as scurvy. It may also be used in the treatment of various other health conditions, including common cold, cancer, and cardiovascular disease, although its effectiveness for these uses is still a matter of scientific debate.
NADPH oxidase is an enzyme complex that plays a crucial role in the production of reactive oxygen species (ROS) in various cell types. The primary function of NADPH oxidase is to catalyze the transfer of electrons from NADPH to molecular oxygen, resulting in the formation of superoxide radicals. This enzyme complex consists of several subunits, including two membrane-bound components (gp91phox and p22phox) and several cytosolic components (p47phox, p67phox, p40phox, and rac1 or rac2). Upon activation, these subunits assemble to form a functional enzyme complex that generates ROS, which serve as important signaling molecules in various cellular processes. However, excessive or uncontrolled production of ROS by NADPH oxidase has been implicated in the pathogenesis of several diseases, such as cardiovascular disorders, neurodegenerative diseases, and cancer.
Isoprostanes are a type of prostaglandin-like compounds that are produced in the body through the free radical-catalyzed peroxidation of arachidonic acid, a polyunsaturated fatty acid found in cell membranes. They are formed in situ on phospholipids and then released as free isoprostanes by the action of phospholipases.
Isoprostanes are chemically stable and can be measured in various biological fluids such as urine, blood, and breath to assess oxidative stress in the body. They have been used as biomarkers for lipid peroxidation and oxidative damage in several diseases, including atherosclerosis, cancer, neurodegenerative disorders, and respiratory diseases.
Isoprostanes can also activate various signaling pathways and contribute to the development of inflammation, vasoconstriction, platelet aggregation, and other physiological responses. Therefore, they play a significant role in the pathogenesis of several diseases associated with oxidative stress and inflammation.
Free radical scavengers, also known as antioxidants, are substances that neutralize or stabilize free radicals. Free radicals are highly reactive atoms or molecules with unpaired electrons, capable of causing damage to cells and tissues in the body through a process called oxidative stress. Antioxidants donate an electron to the free radical, thereby neutralizing it and preventing it from causing further damage. They can be found naturally in foods such as fruits, vegetables, and nuts, or they can be synthesized and used as dietary supplements. Examples of antioxidants include vitamins C and E, beta-carotene, and selenium.
Superoxides are partially reduced derivatives of oxygen that contain one extra electron, giving them an overall charge of -1. They are highly reactive and unstable, with the most common superoxide being the hydroxyl radical (•OH-) and the superoxide anion (O2-). Superoxides are produced naturally in the body during metabolic processes, particularly within the mitochondria during cellular respiration. They play a role in various physiological processes, but when produced in excess or not properly neutralized, they can contribute to oxidative stress and damage to cells and tissues, potentially leading to the development of various diseases such as cancer, atherosclerosis, and neurodegenerative disorders.
Apoptosis is a programmed and controlled cell death process that occurs in multicellular organisms. It is a natural process that helps maintain tissue homeostasis by eliminating damaged, infected, or unwanted cells. During apoptosis, the cell undergoes a series of morphological changes, including cell shrinkage, chromatin condensation, and fragmentation into membrane-bound vesicles called apoptotic bodies. These bodies are then recognized and engulfed by neighboring cells or phagocytic cells, preventing an inflammatory response. Apoptosis is regulated by a complex network of intracellular signaling pathways that involve proteins such as caspases, Bcl-2 family members, and inhibitors of apoptosis (IAPs).
A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.
In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:
1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.
It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.
"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.
Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.
It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.
"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.
Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.
Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.
Medical Definition of Vitamin E:
Vitamin E is a fat-soluble antioxidant that plays a crucial role in protecting your body's cells from damage caused by free radicals, which are unstable molecules produced when your body breaks down food or is exposed to environmental toxins like cigarette smoke and radiation. Vitamin E is also involved in immune function, DNA repair, and other metabolic processes.
It is a collective name for a group of eight fat-soluble compounds that include four tocopherols and four tocotrienols. Alpha-tocopherol is the most biologically active form of vitamin E in humans and is the one most commonly found in supplements.
Vitamin E deficiency is rare but can occur in people with certain genetic disorders or who cannot absorb fat properly. Symptoms of deficiency include nerve and muscle damage, loss of feeling in the arms and legs, muscle weakness, and vision problems.
Food sources of vitamin E include vegetable oils (such as sunflower, safflower, and wheat germ oil), nuts and seeds (like almonds, peanuts, and sunflower seeds), and fortified foods (such as cereals and some fruit juices).
Cell survival refers to the ability of a cell to continue living and functioning normally, despite being exposed to potentially harmful conditions or treatments. This can include exposure to toxins, radiation, chemotherapeutic drugs, or other stressors that can damage cells or interfere with their normal processes.
In scientific research, measures of cell survival are often used to evaluate the effectiveness of various therapies or treatments. For example, researchers may expose cells to a particular drug or treatment and then measure the percentage of cells that survive to assess its potential therapeutic value. Similarly, in toxicology studies, measures of cell survival can help to determine the safety of various chemicals or substances.
It's important to note that cell survival is not the same as cell proliferation, which refers to the ability of cells to divide and multiply. While some treatments may promote cell survival, they may also inhibit cell proliferation, making them useful for treating diseases such as cancer. Conversely, other treatments may be designed to specifically target and kill cancer cells, even if it means sacrificing some healthy cells in the process.
Heme Oxygenase-1 (HO-1) is an inducible enzyme that catalyzes the degradation of heme into biliverdin, iron, and carbon monoxide. It is a rate-limiting enzyme in the oxidative degradation of heme. HO-1 is known to play a crucial role in cellular defense against oxidative stress and inflammation. It is primarily located in the microsomes of many tissues, including the spleen, liver, and brain. Induction of HO-1 has been shown to have cytoprotective effects, while deficiency in HO-1 has been associated with several pathological conditions, such as vascular diseases, neurodegenerative disorders, and cancer.
Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.
The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.
Examples of animal disease models include:
1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.
Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.
Vitamin K3 is not typically referred to as a medical definition, but it is a form of Vitamin K. Medically, Vitamins K are coagulation factors that play a crucial role in blood clotting. Specifically, Vitamin K3 is known as Menadione and it is a synthetic version of Vitamin K. Unlike other forms of Vitamin K (K1 and K2), which are found naturally in foods like leafy green vegetables and fermented products, Vitamin K3 is not found in food and must be synthetically produced in a laboratory. It is used in some dietary supplements and animal feed additives. However, the use of Vitamin K3 in human nutrition is limited due to its potential toxicity, especially when given in large doses or to infants.
Peroxiredoxins (Prx) are a family of peroxidases that play a crucial role in cellular defense against oxidative stress. They catalyze the reduction of hydrogen peroxide, organic hydroperoxides, and peroxynitrite, thereby protecting cells from potentially harmful effects of these reactive oxygen and nitrogen species.
Peroxiredoxins are ubiquitously expressed in various cellular compartments, including the cytosol, mitochondria, and nucleus. They contain a conserved catalytic cysteine residue that gets oxidized during the reduction of peroxides, which is then reduced back to its active form by thioredoxins or other reducing agents.
Dysregulation of peroxiredoxin function has been implicated in various pathological conditions, including cancer, neurodegenerative diseases, and inflammatory disorders. Therefore, understanding the role of peroxiredoxins in cellular redox homeostasis is essential for developing novel therapeutic strategies to treat oxidative stress-related diseases.
Cyclic N-oxides are a class of organic compounds that contain a cyclic structure with a nitrogen atom bonded to an oxygen atom as an N-oxide. An N-oxide is a compound in which the nitrogen atom has a positive charge and the oxygen atom has a negative charge, forming a polar covalent bond. In cyclic N-oxides, this N-O group is part of a ring structure, which can be composed of various combinations of carbon, nitrogen, and other atoms. These compounds have been studied for their potential use in pharmaceuticals, agrochemicals, and materials science.
Glutathione reductase (GR) is an enzyme that plays a crucial role in maintaining the cellular redox state. The primary function of GR is to reduce oxidized glutathione (GSSG) to its reduced form (GSH), which is an essential intracellular antioxidant. This enzyme utilizes nicotinamide adenine dinucleotide phosphate (NADPH) as a reducing agent in the reaction, converting it to NADP+. The medical definition of Glutathione Reductase is:
Glutathione reductase (GSR; EC 1.8.1.7) is a homodimeric flavoprotein that catalyzes the reduction of oxidized glutathione (GSSG) to reduced glutathione (GSH) in the presence of NADPH as a cofactor. This enzyme is essential for maintaining the cellular redox balance and protecting cells from oxidative stress by regenerating the active form of glutathione, a vital antioxidant and detoxifying agent.
Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.
Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.
These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.
Lipid peroxides are chemical compounds that form when lipids (fats or fat-like substances) oxidize. This process, known as lipid peroxidation, involves the reaction of lipids with oxygen in a way that leads to the formation of hydroperoxides and various aldehydes, such as malondialdehyde.
Lipid peroxidation is a naturally occurring process that can also be accelerated by factors such as exposure to radiation, certain chemicals, or enzymatic reactions. It plays a role in many biological processes, including cell signaling and regulation of gene expression, but it can also contribute to the development of various diseases when it becomes excessive.
Examples of lipid peroxides include phospholipid hydroperoxides, cholesteryl ester hydroperoxides, and triglyceride hydroperoxides. These compounds are often used as markers of oxidative stress in biological systems and have been implicated in the pathogenesis of atherosclerosis, cancer, neurodegenerative diseases, and other conditions associated with oxidative damage.
DNA damage refers to any alteration in the structure or composition of deoxyribonucleic acid (DNA), which is the genetic material present in cells. DNA damage can result from various internal and external factors, including environmental exposures such as ultraviolet radiation, tobacco smoke, and certain chemicals, as well as normal cellular processes such as replication and oxidative metabolism.
Examples of DNA damage include base modifications, base deletions or insertions, single-strand breaks, double-strand breaks, and crosslinks between the two strands of the DNA helix. These types of damage can lead to mutations, genomic instability, and chromosomal aberrations, which can contribute to the development of diseases such as cancer, neurodegenerative disorders, and aging-related conditions.
The body has several mechanisms for repairing DNA damage, including base excision repair, nucleotide excision repair, mismatch repair, and double-strand break repair. However, if the damage is too extensive or the repair mechanisms are impaired, the cell may undergo apoptosis (programmed cell death) to prevent the propagation of potentially harmful mutations.
Inflammation is a complex biological response of tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. It is characterized by the following signs: rubor (redness), tumor (swelling), calor (heat), dolor (pain), and functio laesa (loss of function). The process involves the activation of the immune system, recruitment of white blood cells, and release of inflammatory mediators, which contribute to the elimination of the injurious stimuli and initiation of the healing process. However, uncontrolled or chronic inflammation can also lead to tissue damage and diseases.
Free radicals are molecules or atoms that have one or more unpaired electrons in their outermost shell, making them highly reactive. They can be formed naturally in the body through processes such as metabolism and exercise, or they can come from external sources like pollution, radiation, and certain chemicals. Free radicals can cause damage to cells and contribute to the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Antioxidants are substances that can neutralize free radicals and help protect against their harmful effects.
Nitric oxide (NO) is a molecule made up of one nitrogen atom and one oxygen atom. In the body, it is a crucial signaling molecule involved in various physiological processes such as vasodilation, immune response, neurotransmission, and inhibition of platelet aggregation. It is produced naturally by the enzyme nitric oxide synthase (NOS) from the amino acid L-arginine. Inhaled nitric oxide is used medically to treat pulmonary hypertension in newborns and adults, as it helps to relax and widen blood vessels, improving oxygenation and blood flow.
Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.
The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.
Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.
I couldn't find a medical definition for "diamide" as it is not a term commonly used in medicine or biomedical sciences. The term "diamide" is a chemical name that refers to a compound containing two amide groups. It may have various uses in different scientific fields, such as chemistry and biochemistry, but it is not a medical term.
Thioredoxins are a group of small proteins that contain a redox-active disulfide bond and play a crucial role in the redox regulation of cellular processes. They function as electron donors and help to maintain the intracellular reducing environment by reducing disulfide bonds in other proteins, thereby regulating their activity. Thioredoxins also have antioxidant properties and protect cells from oxidative stress by scavenging reactive oxygen species (ROS) and repairing oxidatively damaged proteins. They are widely distributed in various organisms, including bacteria, plants, and animals, and are involved in many physiological processes such as DNA synthesis, protein folding, and apoptosis.
Buthionine Sulfoximine (BSO) is a chemical compound that is known to inhibit the enzyme gamma-glutamylcysteine synthetase, which plays a crucial role in the production of glutathione, a powerful antioxidant in the body. By inhibiting this enzyme, BSO can deplete glutathione levels in cells, making it a useful tool in research to study the effects of glutathione depletion on various biological processes. It is often used in laboratory experiments and clinical trials for its potential therapeutic benefits in cancer treatment and other diseases associated with oxidative stress. However, its use as a therapeutic agent is still being investigated and has not yet been approved by regulatory agencies for widespread clinical use.
Cytoprotection refers to the protection of cells, particularly from harmful agents or damaging conditions. This can be achieved through various mechanisms, such as:
1. Activation of cellular defense pathways that help cells resist damage.
2. Inhibition of oxidative stress and inflammation, which can cause cellular damage.
3. Enhancement of cell repair processes, enabling cells to recover from damage more effectively.
4. Prevention of apoptosis (programmed cell death) or promotion of cell survival signals.
In the medical context, cytoprotective agents are often used to protect tissues and organs from injury due to various factors like chemotherapy, radiation therapy, ischemia-reperfusion injury, or inflammation. These agents can include antioxidants, anti-inflammatory drugs, growth factors, and other compounds that help maintain cellular integrity and function.
C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.
The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.
C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.
One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.
Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.
Cell death is the process by which cells cease to function and eventually die. There are several ways that cells can die, but the two most well-known and well-studied forms of cell death are apoptosis and necrosis.
Apoptosis is a programmed form of cell death that occurs as a normal and necessary process in the development and maintenance of healthy tissues. During apoptosis, the cell's DNA is broken down into small fragments, the cell shrinks, and the membrane around the cell becomes fragmented, allowing the cell to be easily removed by phagocytic cells without causing an inflammatory response.
Necrosis, on the other hand, is a form of cell death that occurs as a result of acute tissue injury or overwhelming stress. During necrosis, the cell's membrane becomes damaged and the contents of the cell are released into the surrounding tissue, causing an inflammatory response.
There are also other forms of cell death, such as autophagy, which is a process by which cells break down their own organelles and proteins to recycle nutrients and maintain energy homeostasis, and pyroptosis, which is a form of programmed cell death that occurs in response to infection and involves the activation of inflammatory caspases.
Cell death is an important process in many physiological and pathological processes, including development, tissue homeostasis, and disease. Dysregulation of cell death can contribute to the development of various diseases, including cancer, neurodegenerative disorders, and autoimmune diseases.
Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).
The Western blotting procedure involves several steps:
1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.
Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.
Dinoprost is a synthetic form of prostaglandin F2α, which is a naturally occurring hormone-like substance in the body. It is used in veterinary medicine as a uterotonic agent to induce labor and abortion in various animals such as cows and pigs. In human medicine, it may be used off-label for similar purposes, but its use must be under the close supervision of a healthcare provider due to potential side effects and risks.
It is important to note that Dinoprost is not approved by the FDA for use in humans, and its availability may vary depending on the country or region. Always consult with a licensed healthcare professional before using any medication, including Dinoprost.
Aging is a complex, progressive and inevitable process of bodily changes over time, characterized by the accumulation of cellular damage and degenerative changes that eventually lead to increased vulnerability to disease and death. It involves various biological, genetic, environmental, and lifestyle factors that contribute to the decline in physical and mental functions. The medical field studies aging through the discipline of gerontology, which aims to understand the underlying mechanisms of aging and develop interventions to promote healthy aging and extend the human healthspan.
The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:
1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.
Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.
Peroxides, in a medical context, most commonly refer to chemical compounds that contain the peroxide ion (O2−2). Peroxides are characterized by the presence of an oxygen-oxygen single bond and can be found in various substances.
In dentistry, hydrogen peroxide (H2O2) is a widely used agent for teeth whitening or bleaching due to its oxidizing properties. It can help remove stains and discoloration on the tooth surface by breaking down into water and oxygen-free radicals, which react with the stain molecules, ultimately leading to their oxidation and elimination.
However, it is essential to note that high concentrations of hydrogen peroxide or prolonged exposure can cause tooth sensitivity, irritation to the oral soft tissues, and potential damage to the dental pulp. Therefore, professional supervision and appropriate concentration control are crucial when using peroxides for dental treatments.
Sulfhydryl compounds, also known as thiol compounds, are organic compounds that contain a functional group consisting of a sulfur atom bonded to a hydrogen atom (-SH). This functional group is also called a sulfhydryl group. Sulfhydryl compounds can be found in various biological systems and play important roles in maintaining the structure and function of proteins, enzymes, and other biomolecules. They can also act as antioxidants and help protect cells from damage caused by reactive oxygen species. Examples of sulfhydryl compounds include cysteine, glutathione, and coenzyme A.
A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.
The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.
The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.
In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.
A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.
In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.
For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.
Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.
Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.
Reactive Nitrogen Species (RNS) are a group of highly reactive and chemically diverse molecules that are derived from nitric oxide (NO) or other nitrogen-containing compounds. They play important roles in various biological processes, such as cell signaling, neurotransmission, and immune response. However, an overproduction of RNS can also contribute to the development of several pathological conditions, including inflammation, neurodegenerative diseases, and cancer. Examples of RNS include nitric oxide (NO), peroxynitrite (ONOO-), and nitrogen dioxide (NO2). These species are generated through various biochemical reactions, such as the conversion of L-arginine to citrulline by nitric oxide synthase (NOS) enzymes, which leads to the production of NO. RNS can then react with other molecules in the body, such as reactive oxygen species (ROS), leading to the formation of harmful compounds that can damage cellular structures and disrupt normal physiological functions.
A plant extract is a preparation containing chemical constituents that have been extracted from a plant using a solvent. The resulting extract may contain a single compound or a mixture of several compounds, depending on the extraction process and the specific plant material used. These extracts are often used in various industries including pharmaceuticals, nutraceuticals, cosmetics, and food and beverage, due to their potential therapeutic or beneficial properties. The composition of plant extracts can vary widely, and it is important to ensure their quality, safety, and efficacy before use in any application.
Mitochondrial membrane potential is the electric potential difference (voltage) across the inner mitochondrial membrane. It is negative inside the mitochondria and positive outside. This electrical gradient is established by the active transport of hydrogen ions (protons) out of the mitochondrial matrix and into the intermembrane space by complexes in the electron transport chain during oxidative phosphorylation. The energy stored in this electrochemical gradient is used to generate ATP, which is the main source of energy for cellular metabolism.
A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.
Alpha-tocopherol is the most active form of vitamin E in humans and is a fat-soluble antioxidant that helps protect cells from damage caused by free radicals. It plays a role in immune function, cell signaling, and metabolic processes. Alpha-tocopherol is found naturally in foods such as nuts, seeds, leafy green vegetables, and vegetable oils, and it is also available as a dietary supplement.
In the context of medicine, iron is an essential micromineral and key component of various proteins and enzymes. It plays a crucial role in oxygen transport, DNA synthesis, and energy production within the body. Iron exists in two main forms: heme and non-heme. Heme iron is derived from hemoglobin and myoglobin in animal products, while non-heme iron comes from plant sources and supplements.
The recommended daily allowance (RDA) for iron varies depending on age, sex, and life stage:
* For men aged 19-50 years, the RDA is 8 mg/day
* For women aged 19-50 years, the RDA is 18 mg/day
* During pregnancy, the RDA increases to 27 mg/day
* During lactation, the RDA for breastfeeding mothers is 9 mg/day
Iron deficiency can lead to anemia, characterized by fatigue, weakness, and shortness of breath. Excessive iron intake may result in iron overload, causing damage to organs such as the liver and heart. Balanced iron levels are essential for maintaining optimal health.
Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.
The endothelium is a thin layer of simple squamous epithelial cells that lines the interior surface of blood vessels, lymphatic vessels, and heart chambers. The vascular endothelium, specifically, refers to the endothelial cells that line the blood vessels. These cells play a crucial role in maintaining vascular homeostasis by regulating vasomotor tone, coagulation, platelet activation, inflammation, and permeability of the vessel wall. They also contribute to the growth and repair of the vascular system and are involved in various pathological processes such as atherosclerosis, hypertension, and diabetes.
Thioctic acid is also known as alpha-lipoic acid. It is a vitamin-like chemical compound that is made naturally in the body and is found in small amounts in some foods like spinach, broccoli, and potatoes. Thioctic acid is an antioxidant that helps to protect cells from damage caused by free radicals. It also plays a role in energy production in the cells and has been studied for its potential benefits in the treatment of diabetes and nerve-related symptoms of diabetes such as pain, burning, itching, and numbness. Thioctic acid is available as a dietary supplement.
Medical Definition: Thioctic acid (also known as alpha-lipoic acid) is a vitamin-like antioxidant that is made naturally in the body and is found in small amounts in some foods. It plays a role in energy production in the cells, and has been studied for its potential benefits in the treatment of diabetes and nerve-related symptoms of diabetes such as pain, burning, itching, and numbness. Thioctic acid is also available as a dietary supplement.
Glutamate-cysteine ligase (GCL) is an essential enzyme in the biosynthesis of glutathione, a major antioxidant in cells. It catalyzes the reaction between glutamate and cysteine to form γ-glutamylcysteine, which is then combined with glycine by glutathione synthetase to produce glutathione.
GCL has two subunits: a catalytic subunit (GCLC) and a modulatory subunit (GCLM). The former contains the active site for the formation of the peptide bond between glutamate and cysteine, while the latter regulates the activity of GCLC by affecting its sensitivity to feedback inhibition by glutathione.
The proper functioning of GCL is critical for maintaining cellular redox homeostasis and protecting against oxidative stress, making it a potential target for therapeutic intervention in various diseases associated with oxidative damage, such as neurodegenerative disorders, cancer, and aging-related conditions.
'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.
Xanthine oxidase is an enzyme that catalyzes the oxidation of xanthine to uric acid, which is the last step in purine metabolism. It's a type of molybdenum-containing oxidoreductase that generates reactive oxygen species (ROS) during its reaction mechanism.
The enzyme exists in two interconvertible forms: an oxidized state and a reduced state. The oxidized form, called xanthine oxidase, reduces molecular oxygen to superoxide and hydrogen peroxide, while the reduced form, called xanthine dehydrogenase, reduces NAD+ to NADH.
Xanthine oxidase is found in various tissues, including the liver, intestines, and milk. An overproduction of uric acid due to increased activity of xanthine oxidase can lead to hyperuricemia, which may result in gout or kidney stones. Some medications and natural compounds are known to inhibit xanthine oxidase, such as allopurinol and febuxostat, which are used to treat gout and prevent the formation of uric acid stones in the kidneys.
I couldn't find a medical definition specifically for "Diabetes Mellitus, Experimental." However, I can provide you with information about experimental diabetes research and its relevance to understanding the disease.
Experimental diabetes models are used in biomedical research to study the pathophysiology of diabetes mellitus and to test potential therapies or treatments. These models can be broadly categorized into two types: chemically-induced and genetically modified.
1. Chemically-induced diabetes models: These involve administering chemicals, such as alloxan or streptozotocin, to animals (commonly mice or rats) to destroy their pancreatic β-cells, which produce insulin. This results in hyperglycemia and symptoms similar to those seen in type 1 diabetes in humans.
2. Genetically modified diabetes models: These involve altering the genes of animals (commonly mice) to create a diabetes phenotype. Examples include non-obese diabetic (NOD) mice, which develop an autoimmune form of diabetes similar to human type 1 diabetes, and various strains of obese mice with insulin resistance, such as ob/ob or db/db mice, which model aspects of type 2 diabetes.
These experimental models help researchers better understand the mechanisms behind diabetes development and progression, identify new therapeutic targets, and test potential treatments before moving on to human clinical trials. However, it's essential to recognize that these models may not fully replicate all aspects of human diabetes, so findings from animal studies should be interpreted with caution.
Acetophenones are organic compounds that consist of a phenyl group (a benzene ring with a hydroxyl group replaced by a hydrogen atom) bonded to an acetyl group (a carbonyl group bonded to a methyl group). The chemical structure can be represented as CH3COC6H5.
Acetophenones are aromatic ketones and can be found in essential oils of various plants, as well as in some synthetic fragrances. They have a characteristic sweet, fruity odor and are used in the perfume industry. In addition to their use as fragrances, acetophenones have been studied for their potential medicinal properties, including anti-inflammatory, antimicrobial, and analgesic effects. However, more research is needed before they can be considered safe and effective for medical use.
Oxygen is a colorless, odorless, tasteless gas that constitutes about 21% of the earth's atmosphere. It is a crucial element for human and most living organisms as it is vital for respiration. Inhaled oxygen enters the lungs and binds to hemoglobin in red blood cells, which carries it to tissues throughout the body where it is used to convert nutrients into energy and carbon dioxide, a waste product that is exhaled.
Medically, supplemental oxygen therapy may be provided to patients with conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or other medical conditions that impair the body's ability to extract sufficient oxygen from the air. Oxygen can be administered through various devices, including nasal cannulas, face masks, and ventilators.
Peroxidases are a group of enzymes that catalyze the oxidation of various substrates using hydrogen peroxide (H2O2) as the electron acceptor. These enzymes contain a heme prosthetic group, which plays a crucial role in their catalytic activity. Peroxidases are widely distributed in nature and can be found in plants, animals, and microorganisms. They play important roles in various biological processes, including defense against oxidative stress, lignin degradation, and host-pathogen interactions. Some common examples of peroxidases include glutathione peroxidase, which helps protect cells from oxidative damage, and horseradish peroxidase, which is often used in laboratory research.
Up-regulation is a term used in molecular biology and medicine to describe an increase in the expression or activity of a gene, protein, or receptor in response to a stimulus. This can occur through various mechanisms such as increased transcription, translation, or reduced degradation of the molecule. Up-regulation can have important functional consequences, for example, enhancing the sensitivity or response of a cell to a hormone, neurotransmitter, or drug. It is a normal physiological process that can also be induced by disease or pharmacological interventions.
"Spin labels" are a term used in the field of magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR). They refer to molecules or atoms that have been chemically attached to a system of interest and possess a stable, unpaired electron. This unpaired electron behaves like a tiny magnet and can be manipulated using magnetic fields and radiofrequency pulses in EPR experiments. The resulting changes in the electron's spin state can provide information about the local environment, dynamics, and structure of the system to which it is attached. Spin labels are often used in biochemistry and materials science to study complex biological systems or materials at the molecular level.
Longevity, in a medical context, refers to the condition of living for a long period of time. It is often used to describe individuals who have reached a advanced age, such as 85 years or older, and is sometimes associated with the study of aging and factors that contribute to a longer lifespan.
It's important to note that longevity can be influenced by various genetic and environmental factors, including family history, lifestyle choices, and access to quality healthcare. Some researchers are also studying the potential impact of certain medical interventions, such as stem cell therapies and caloric restriction, on lifespan and healthy aging.
Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.
The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.
In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.
RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.
In the context of medicine and toxicology, protective agents are substances that provide protection against harmful or damaging effects of other substances. They can work in several ways, such as:
1. Binding to toxic substances: Protective agents can bind to toxic substances, rendering them inactive or less active, and preventing them from causing harm. For example, activated charcoal is sometimes used in the emergency treatment of certain types of poisoning because it can bind to certain toxins in the stomach and intestines and prevent their absorption into the body.
2. Increasing elimination: Protective agents can increase the elimination of toxic substances from the body, for example by promoting urinary or biliary excretion.
3. Reducing oxidative stress: Antioxidants are a type of protective agent that can reduce oxidative stress caused by free radicals and reactive oxygen species (ROS). These agents can protect cells and tissues from damage caused by oxidation.
4. Supporting organ function: Protective agents can support the function of organs that have been damaged by toxic substances, for example by improving blood flow or reducing inflammation.
Examples of protective agents include chelating agents, antidotes, free radical scavengers, and anti-inflammatory drugs.
A kidney, in medical terms, is one of two bean-shaped organs located in the lower back region of the body. They are essential for maintaining homeostasis within the body by performing several crucial functions such as:
1. Regulation of water and electrolyte balance: Kidneys help regulate the amount of water and various electrolytes like sodium, potassium, and calcium in the bloodstream to maintain a stable internal environment.
2. Excretion of waste products: They filter waste products from the blood, including urea (a byproduct of protein metabolism), creatinine (a breakdown product of muscle tissue), and other harmful substances that result from normal cellular functions or external sources like medications and toxins.
3. Endocrine function: Kidneys produce several hormones with important roles in the body, such as erythropoietin (stimulates red blood cell production), renin (regulates blood pressure), and calcitriol (activated form of vitamin D that helps regulate calcium homeostasis).
4. pH balance regulation: Kidneys maintain the proper acid-base balance in the body by excreting either hydrogen ions or bicarbonate ions, depending on whether the blood is too acidic or too alkaline.
5. Blood pressure control: The kidneys play a significant role in regulating blood pressure through the renin-angiotensin-aldosterone system (RAAS), which constricts blood vessels and promotes sodium and water retention to increase blood volume and, consequently, blood pressure.
Anatomically, each kidney is approximately 10-12 cm long, 5-7 cm wide, and 3 cm thick, with a weight of about 120-170 grams. They are surrounded by a protective layer of fat and connected to the urinary system through the renal pelvis, ureters, bladder, and urethra.
Glutathione transferases (GSTs) are a group of enzymes involved in the detoxification of xenobiotics and endogenous compounds. They facilitate the conjugation of these compounds with glutathione, a tripeptide consisting of cysteine, glutamic acid, and glycine, which results in more water-soluble products that can be easily excreted from the body.
GSTs play a crucial role in protecting cells against oxidative stress and chemical injury by neutralizing reactive electrophilic species and peroxides. They are found in various tissues, including the liver, kidneys, lungs, and intestines, and are classified into several families based on their structure and function.
Abnormalities in GST activity have been associated with increased susceptibility to certain diseases, such as cancer, neurological disorders, and respiratory diseases. Therefore, GSTs have become a subject of interest in toxicology, pharmacology, and clinical research.
A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.
Peroxynitrous acid (ONOOH) is a highly reactive nitrogen species formed from the reaction between nitric oxide (NO) and superoxide radical (O2-). It is an unstable compound that quickly decomposes to form other reactive species, such as nitrogen dioxide (NO2) and hydroxyl radical (HO•), which can cause significant damage to biological molecules, including proteins, lipids, and DNA. Peroxynitrous acid has been implicated in the pathogenesis of various diseases, including neurodegenerative disorders, cardiovascular disease, and cancer.
Enzyme activation refers to the process by which an enzyme becomes biologically active and capable of carrying out its specific chemical or biological reaction. This is often achieved through various post-translational modifications, such as proteolytic cleavage, phosphorylation, or addition of cofactors or prosthetic groups to the enzyme molecule. These modifications can change the conformation or structure of the enzyme, exposing or creating a binding site for the substrate and allowing the enzymatic reaction to occur.
For example, in the case of proteolytic cleavage, an inactive precursor enzyme, known as a zymogen, is cleaved into its active form by a specific protease. This is seen in enzymes such as trypsin and chymotrypsin, which are initially produced in the pancreas as inactive precursors called trypsinogen and chymotrypsinogen, respectively. Once they reach the small intestine, they are activated by enteropeptidase, a protease that cleaves a specific peptide bond, releasing the active enzyme.
Phosphorylation is another common mechanism of enzyme activation, where a phosphate group is added to a specific serine, threonine, or tyrosine residue on the enzyme by a protein kinase. This modification can alter the conformation of the enzyme and create a binding site for the substrate, allowing the enzymatic reaction to occur.
Enzyme activation is a crucial process in many biological pathways, as it allows for precise control over when and where specific reactions take place. It also provides a mechanism for regulating enzyme activity in response to various signals and stimuli, such as hormones, neurotransmitters, or changes in the intracellular environment.
Physiological stress is a response of the body to a demand or threat that disrupts homeostasis and activates the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis. This results in the release of stress hormones such as adrenaline, cortisol, and noradrenaline, which prepare the body for a "fight or flight" response. Increased heart rate, rapid breathing, heightened sensory perception, and increased alertness are some of the physiological changes that occur during this response. Chronic stress can have negative effects on various bodily functions, including the immune, cardiovascular, and nervous systems.
Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.
Examples of biological models include:
1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.
Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.
Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.
The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.
Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.
Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.
Aconitate hydratase is an enzyme that catalyzes the reversible conversion of citrate to isocitrate in the Krebs cycle (also known as the tricarboxylic acid cycle or TCA cycle), which is a central metabolic pathway in the cell. This enzyme is also called aconitase or aconitate dehydratase.
The reaction catalyzed by aconitate hydratase involves two steps: first, the removal of a water molecule from citrate to form cis-aconitate; and second, the addition of a water molecule to cis-aconitate to form isocitrate. The enzyme binds to the substrate in such a way that it stabilizes the transition state between citrate and cis-aconitate, making the reaction more favorable.
Aconitate hydratase plays an important role in energy metabolism, as it helps generate NADH and FADH2, which are used to produce ATP through oxidative phosphorylation. Additionally, aconitate hydratase has been implicated in various diseases, including neurodegenerative disorders, cancer, and bacterial infections.
Caspase-3 is a type of protease enzyme that plays a central role in the execution-phase of cell apoptosis, or programmed cell death. It's also known as CPP32 (CPP for ced-3 protease precursor) or apopain. Caspase-3 is produced as an inactive protein that is activated when cleaved by other caspases during the early stages of apoptosis. Once activated, it cleaves a variety of cellular proteins, including structural proteins, enzymes, and signal transduction proteins, leading to the characteristic morphological and biochemical changes associated with apoptotic cell death. Caspase-3 is often referred to as the "death protease" because of its crucial role in executing the cell death program.
Enzyme inhibitors are substances that bind to an enzyme and decrease its activity, preventing it from catalyzing a chemical reaction in the body. They can work by several mechanisms, including blocking the active site where the substrate binds, or binding to another site on the enzyme to change its shape and prevent substrate binding. Enzyme inhibitors are often used as drugs to treat various medical conditions, such as high blood pressure, abnormal heart rhythms, and bacterial infections. They can also be found naturally in some foods and plants, and can be used in research to understand enzyme function and regulation.
Neuroprotective agents are substances that protect neurons or nerve cells from damage, degeneration, or death caused by various factors such as trauma, inflammation, oxidative stress, or excitotoxicity. These agents work through different mechanisms, including reducing the production of free radicals, inhibiting the release of glutamate (a neurotransmitter that can cause cell damage in high concentrations), promoting the growth and survival of neurons, and preventing apoptosis (programmed cell death). Neuroprotective agents have been studied for their potential to treat various neurological disorders, including stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease, and multiple sclerosis. However, more research is needed to fully understand their mechanisms of action and to develop effective therapies.
The myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.
The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.
Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.
Metalloporphyrins are a type of porphyrin molecule that contain a metal ion at their center. Porphyrins are complex organic compounds containing four modified pyrrole rings connected to form a planar, aromatic ring known as a porphine. When a metal ion is incorporated into the center of the porphyrin ring, it forms a metalloporphyrin.
These molecules have great biological significance, as they are involved in various essential processes within living organisms. For instance, heme, a type of iron-containing porphyrin, plays a crucial role in oxygen transport and storage in the body by forming part of hemoglobin and myoglobin molecules. Chlorophyll, another metalloporphyrin with magnesium at its center, is essential for photosynthesis in plants, algae, and some bacteria.
Metalloporphyrins have also found applications in several industrial and medical fields, including catalysis, sensors, and pharmaceuticals. Their unique structure and properties make them valuable tools for researchers and scientists to study and utilize in various ways.
A dietary supplement is a product that contains nutrients, such as vitamins, minerals, amino acids, herbs or other botanicals, and is intended to be taken by mouth, to supplement the diet. Dietary supplements can include a wide range of products, such as vitamin and mineral supplements, herbal supplements, and sports nutrition products.
Dietary supplements are not intended to treat, diagnose, cure, or alleviate the effects of diseases. They are intended to be used as a way to add extra nutrients to the diet or to support specific health functions. It is important to note that dietary supplements are not subject to the same rigorous testing and regulations as drugs, so it is important to choose products carefully and consult with a healthcare provider if you have any questions or concerns about using them.
Gene expression profiling is a laboratory technique used to measure the activity (expression) of thousands of genes at once. This technique allows researchers and clinicians to identify which genes are turned on or off in a particular cell, tissue, or organism under specific conditions, such as during health, disease, development, or in response to various treatments.
The process typically involves isolating RNA from the cells or tissues of interest, converting it into complementary DNA (cDNA), and then using microarray or high-throughput sequencing technologies to determine which genes are expressed and at what levels. The resulting data can be used to identify patterns of gene expression that are associated with specific biological states or processes, providing valuable insights into the underlying molecular mechanisms of diseases and potential targets for therapeutic intervention.
In recent years, gene expression profiling has become an essential tool in various fields, including cancer research, drug discovery, and personalized medicine, where it is used to identify biomarkers of disease, predict patient outcomes, and guide treatment decisions.
NF-κB (Nuclear Factor kappa-light-chain-enhancer of activated B cells) is a protein complex that plays a crucial role in regulating the immune response to infection and inflammation, as well as in cell survival, differentiation, and proliferation. It is composed of several subunits, including p50, p52, p65 (RelA), c-Rel, and RelB, which can form homodimers or heterodimers that bind to specific DNA sequences called κB sites in the promoter regions of target genes.
Under normal conditions, NF-κB is sequestered in the cytoplasm by inhibitory proteins known as IκBs (inhibitors of κB). However, upon stimulation by various signals such as cytokines, bacterial or viral products, and stress, IκBs are phosphorylated, ubiquitinated, and degraded, leading to the release and activation of NF-κB. Activated NF-κB then translocates to the nucleus, where it binds to κB sites and regulates the expression of target genes involved in inflammation, immunity, cell survival, and proliferation.
Dysregulation of NF-κB signaling has been implicated in various pathological conditions such as cancer, chronic inflammation, autoimmune diseases, and neurodegenerative disorders. Therefore, targeting NF-κB signaling has emerged as a potential therapeutic strategy for the treatment of these diseases.
Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein or RNA molecule. This process involves several steps: transcription, RNA processing, and translation. During transcription, the genetic information in DNA is copied into a complementary RNA molecule, known as messenger RNA (mRNA). The mRNA then undergoes RNA processing, which includes adding a cap and tail to the mRNA and splicing out non-coding regions called introns. The resulting mature mRNA is then translated into a protein on ribosomes in the cytoplasm through the process of translation.
The regulation of gene expression is a complex and highly controlled process that allows cells to respond to changes in their environment, such as growth factors, hormones, and stress signals. This regulation can occur at various stages of gene expression, including transcriptional activation or repression, RNA processing, mRNA stability, and translation. Dysregulation of gene expression has been implicated in many diseases, including cancer, genetic disorders, and neurological conditions.
Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.
Cytochrome P-450 CYP2E1 is a specific isoform of the cytochrome P-450 enzyme system, which is involved in the metabolism of various xenobiotics and endogenous compounds. This enzyme is primarily located in the liver and to some extent in other organs such as the lungs, brain, and kidneys.
CYP2E1 plays a significant role in the metabolic activation of several procarcinogens, including nitrosamines, polycyclic aromatic hydrocarbons, and certain solvents. It also contributes to the oxidation of various therapeutic drugs, such as acetaminophen, anesthetics, and anticonvulsants. Overexpression or induction of CYP2E1 has been linked to increased susceptibility to chemical-induced toxicity, carcinogenesis, and alcohol-related liver damage.
The activity of CYP2E1 can be influenced by various factors, including genetic polymorphisms, age, sex, smoking status, and exposure to certain chemicals or drugs. Understanding the regulation and function of this enzyme is crucial for predicting individual susceptibility to chemical-induced toxicities and diseases, as well as for optimizing drug therapy and minimizing adverse effects.
Gene expression regulation, enzymologic refers to the biochemical processes and mechanisms that control the transcription and translation of specific genes into functional proteins or enzymes. This regulation is achieved through various enzymatic activities that can either activate or repress gene expression at different levels, such as chromatin remodeling, transcription factor activation, mRNA processing, and protein degradation.
Enzymologic regulation of gene expression involves the action of specific enzymes that catalyze chemical reactions involved in these processes. For example, histone-modifying enzymes can alter the structure of chromatin to make genes more or less accessible for transcription, while RNA polymerase and its associated factors are responsible for transcribing DNA into mRNA. Additionally, various enzymes are involved in post-transcriptional modifications of mRNA, such as splicing, capping, and tailing, which can affect the stability and translation of the transcript.
Overall, the enzymologic regulation of gene expression is a complex and dynamic process that allows cells to respond to changes in their environment and maintain proper physiological function.
Tyrosine is an non-essential amino acid, which means that it can be synthesized by the human body from another amino acid called phenylalanine. Its name is derived from the Greek word "tyros," which means cheese, as it was first isolated from casein, a protein found in cheese.
Tyrosine plays a crucial role in the production of several important substances in the body, including neurotransmitters such as dopamine, norepinephrine, and epinephrine, which are involved in various physiological processes, including mood regulation, stress response, and cognitive functions. It also serves as a precursor to melanin, the pigment responsible for skin, hair, and eye color.
In addition, tyrosine is involved in the structure of proteins and is essential for normal growth and development. Some individuals may require tyrosine supplementation if they have a genetic disorder that affects tyrosine metabolism or if they are phenylketonurics (PKU), who cannot metabolize phenylalanine, which can lead to elevated tyrosine levels in the blood. However, it is important to consult with a healthcare professional before starting any supplementation regimen.
Peroxiredoxin III (PrxIII) is an antioxidant enzyme that belongs to the peroxiredoxin family. It plays a crucial role in maintaining the redox balance within cells by reducing hydrogen peroxide and other organic peroxides into water and alcohol, respectively. PrxIII is primarily located in the mitochondrial matrix, where it protects against oxidative damage to proteins, lipids, and DNA caused by reactive oxygen species (ROS). It functions as a homodimer and contains a conserved catalytic cysteine residue that gets oxidized during the reduction of peroxides. This oxidized form can be reduced back to its active state by thioredoxin or other reducing agents, allowing PrxIII to continue scavenging ROS. Mutations in the PRDX3 gene, which encodes Peroxiredoxin III, have been associated with various pathological conditions, including neurodegenerative diseases and cancer.
Cysteine is a semi-essential amino acid, which means that it can be produced by the human body under normal circumstances, but may need to be obtained from external sources in certain conditions such as illness or stress. Its chemical formula is HO2CCH(NH2)CH2SH, and it contains a sulfhydryl group (-SH), which allows it to act as a powerful antioxidant and participate in various cellular processes.
Cysteine plays important roles in protein structure and function, detoxification, and the synthesis of other molecules such as glutathione, taurine, and coenzyme A. It is also involved in wound healing, immune response, and the maintenance of healthy skin, hair, and nails.
Cysteine can be found in a variety of foods, including meat, poultry, fish, dairy products, eggs, legumes, nuts, seeds, and some grains. It is also available as a dietary supplement and can be used in the treatment of various medical conditions such as liver disease, bronchitis, and heavy metal toxicity. However, excessive intake of cysteine may have adverse effects on health, including gastrointestinal disturbances, nausea, vomiting, and headaches.
Nitric Oxide Synthase Type III (NOS-III), also known as endothelial Nitric Oxide Synthase (eNOS), is an enzyme responsible for the production of nitric oxide (NO) in the endothelium, the lining of blood vessels. This enzyme catalyzes the conversion of L-arginine to L-citrulline, producing NO as a byproduct. The release of NO from eNOS plays an important role in regulating vascular tone and homeostasis, including the relaxation of smooth muscle cells in the blood vessel walls, inhibition of platelet aggregation, and modulation of immune function. Mutations or dysfunction in NOS-III can contribute to various cardiovascular diseases such as hypertension, atherosclerosis, and erectile dysfunction.
Aryldialkylphosphatases are a group of enzymes that catalyze the hydrolysis of certain types of organophosphate compounds. Specifically, they break down compounds that contain an aryl (aromatic) group linked to two alkyl groups through a phosphorus atom. These enzymes play a role in the detoxification of these compounds in living organisms.
The medical definition of 'Aryldialkylphosphatase' is not commonly used, as it refers to a specific type of enzyme that is not typically discussed in a clinical context. However, understanding the function of these enzymes can be important for toxicologists and other researchers who study the effects of organophosphate compounds on living systems.
The retinal pigment epithelium (RPE) is a single layer of cells located between the photoreceptor cells of the retina and the choroid, which is a part of the eye containing blood vessels. The RPE plays a crucial role in maintaining the health and function of the photoreceptors by providing them with nutrients, removing waste products, and helping to regulate the light-sensitive visual pigments within the photoreceptors.
The RPE cells contain pigment granules that absorb excess light to prevent scattering within the eye and improve visual acuity. They also help to form the blood-retina barrier, which restricts the movement of certain molecules between the retina and the choroid, providing an important protective function for the retina.
Damage to the RPE can lead to a variety of eye conditions, including age-related macular degeneration (AMD), which is a leading cause of vision loss in older adults.
Cellular aging, also known as cellular senescence, is a natural process that occurs as cells divide and grow older. Over time, cells accumulate damage to their DNA, proteins, and lipids due to various factors such as genetic mutations, oxidative stress, and epigenetic changes. This damage can impair the cell's ability to function properly and can lead to changes associated with aging, such as decreased tissue repair and regeneration, increased inflammation, and increased risk of age-related diseases.
Cellular aging is characterized by several features, including:
1. Shortened telomeres: Telomeres are the protective caps on the ends of chromosomes that shorten each time a cell divides. When telomeres become too short, the cell can no longer divide and becomes senescent or dies.
2. Epigenetic changes: Epigenetic modifications refer to chemical changes to DNA and histone proteins that affect gene expression without changing the underlying genetic code. As cells age, they accumulate epigenetic changes that can alter gene expression and contribute to cellular aging.
3. Oxidative stress: Reactive oxygen species (ROS) are byproducts of cellular metabolism that can damage DNA, proteins, and lipids. Accumulated ROS over time can lead to oxidative stress, which is associated with cellular aging.
4. Inflammation: Senescent cells produce pro-inflammatory cytokines, chemokines, and matrix metalloproteinases that contribute to a low-grade inflammation known as inflammaging. This chronic inflammation can lead to tissue damage and increase the risk of age-related diseases.
5. Genomic instability: DNA damage accumulates with age, leading to genomic instability and an increased risk of mutations and cancer.
Understanding cellular aging is crucial for developing interventions that can delay or prevent age-related diseases and improve healthy lifespan.
Phosphorylation is the process of adding a phosphate group (a molecule consisting of one phosphorus atom and four oxygen atoms) to a protein or other organic molecule, which is usually done by enzymes called kinases. This post-translational modification can change the function, localization, or activity of the target molecule, playing a crucial role in various cellular processes such as signal transduction, metabolism, and regulation of gene expression. Phosphorylation is reversible, and the removal of the phosphate group is facilitated by enzymes called phosphatases.
Benzene derivatives are chemical compounds that are derived from benzene, which is a simple aromatic hydrocarbon with the molecular formula C6H6. Benzene has a planar, hexagonal ring structure, and its derivatives are formed by replacing one or more of the hydrogen atoms in the benzene molecule with other functional groups.
Benzene derivatives have a wide range of applications in various industries, including pharmaceuticals, dyes, plastics, and explosives. Some common examples of benzene derivatives include toluene, xylene, phenol, aniline, and nitrobenzene. These compounds can have different physical and chemical properties depending on the nature and position of the substituents attached to the benzene ring.
It is important to note that some benzene derivatives are known to be toxic or carcinogenic, and their production, use, and disposal must be carefully regulated to ensure safety and protect public health.
Endothelial cells are the type of cells that line the inner surface of blood vessels, lymphatic vessels, and heart chambers. They play a crucial role in maintaining vascular homeostasis by controlling vasomotor tone, coagulation, platelet activation, and inflammation. Endothelial cells also regulate the transport of molecules between the blood and surrounding tissues, and contribute to the maintenance of the structural integrity of the vasculature. They are flat, elongated cells with a unique morphology that allows them to form a continuous, nonthrombogenic lining inside the vessels. Endothelial cells can be isolated from various tissues and cultured in vitro for research purposes.
Glutaredoxins (Grxs) are small, ubiquitous proteins that belong to the thioredoxin superfamily. They play a crucial role in maintaining the redox balance within cells by catalyzing the reversible reduction of disulfide bonds and mixed disulfides between protein thiols and low molecular weight compounds, using glutathione (GSH) as a reducing cofactor.
Glutaredoxins are involved in various cellular processes, such as:
1. DNA synthesis and repair
2. Protein folding and degradation
3. Antioxidant defense
4. Regulation of enzyme activities
5. Iron-sulfur cluster biogenesis
There are two main classes of glutaredoxins, Grx1 and Grx2, which differ in their active site sequences and functions. In humans, Grx1 is primarily located in the cytosol, while Grx2 is found in both the cytosol and mitochondria.
The medical relevance of glutaredoxins lies in their role as antioxidant proteins that protect cells from oxidative stress and maintain cellular redox homeostasis. Dysregulation of glutaredoxin function has been implicated in several pathological conditions, including neurodegenerative diseases, cancer, and aging-related disorders.
Glucose is a simple monosaccharide (or single sugar) that serves as the primary source of energy for living organisms. It's a fundamental molecule in biology, often referred to as "dextrose" or "grape sugar." Glucose has the molecular formula C6H12O6 and is vital to the functioning of cells, especially those in the brain and nervous system.
In the body, glucose is derived from the digestion of carbohydrates in food, and it's transported around the body via the bloodstream to cells where it can be used for energy. Cells convert glucose into a usable form through a process called cellular respiration, which involves a series of metabolic reactions that generate adenosine triphosphate (ATP)—the main currency of energy in cells.
Glucose is also stored in the liver and muscles as glycogen, a polysaccharide (multiple sugar) that can be broken down back into glucose when needed for energy between meals or during physical activity. Maintaining appropriate blood glucose levels is crucial for overall health, and imbalances can lead to conditions such as diabetes mellitus.
A cell line that is derived from tumor cells and has been adapted to grow in culture. These cell lines are often used in research to study the characteristics of cancer cells, including their growth patterns, genetic changes, and responses to various treatments. They can be established from many different types of tumors, such as carcinomas, sarcomas, and leukemias. Once established, these cell lines can be grown and maintained indefinitely in the laboratory, allowing researchers to conduct experiments and studies that would not be feasible using primary tumor cells. It is important to note that tumor cell lines may not always accurately represent the behavior of the original tumor, as they can undergo genetic changes during their time in culture.
Gene expression regulation in bacteria refers to the complex cellular processes that control the production of proteins from specific genes. This regulation allows bacteria to adapt to changing environmental conditions and ensure the appropriate amount of protein is produced at the right time.
Bacteria have a variety of mechanisms for regulating gene expression, including:
1. Operon structure: Many bacterial genes are organized into operons, which are clusters of genes that are transcribed together as a single mRNA molecule. The expression of these genes can be coordinately regulated by controlling the transcription of the entire operon.
2. Promoter regulation: Transcription is initiated at promoter regions upstream of the gene or operon. Bacteria have regulatory proteins called sigma factors that bind to the promoter and recruit RNA polymerase, the enzyme responsible for transcribing DNA into RNA. The binding of sigma factors can be influenced by environmental signals, allowing for regulation of transcription.
3. Attenuation: Some operons have regulatory regions called attenuators that control transcription termination. These regions contain hairpin structures that can form in the mRNA and cause transcription to stop prematurely. The formation of these hairpins is influenced by the concentration of specific metabolites, allowing for regulation of gene expression based on the availability of those metabolites.
4. Riboswitches: Some bacterial mRNAs contain regulatory elements called riboswitches that bind small molecules directly. When a small molecule binds to the riboswitch, it changes conformation and affects transcription or translation of the associated gene.
5. CRISPR-Cas systems: Bacteria use CRISPR-Cas systems for adaptive immunity against viruses and plasmids. These systems incorporate short sequences from foreign DNA into their own genome, which can then be used to recognize and cleave similar sequences in invading genetic elements.
Overall, gene expression regulation in bacteria is a complex process that allows them to respond quickly and efficiently to changing environmental conditions. Understanding these regulatory mechanisms can provide insights into bacterial physiology and help inform strategies for controlling bacterial growth and behavior.
Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.
The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:
1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.
The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.
Analysis of Variance (ANOVA) is a statistical technique used to compare the means of two or more groups and determine whether there are any significant differences between them. It is a way to analyze the variance in a dataset to determine whether the variability between groups is greater than the variability within groups, which can indicate that the groups are significantly different from one another.
ANOVA is based on the concept of partitioning the total variance in a dataset into two components: variance due to differences between group means (also known as "between-group variance") and variance due to differences within each group (also known as "within-group variance"). By comparing these two sources of variance, ANOVA can help researchers determine whether any observed differences between groups are statistically significant, or whether they could have occurred by chance.
ANOVA is a widely used technique in many areas of research, including biology, psychology, engineering, and business. It is often used to compare the means of two or more experimental groups, such as a treatment group and a control group, to determine whether the treatment had a significant effect. ANOVA can also be used to compare the means of different populations or subgroups within a population, to identify any differences that may exist between them.
Ubiquinone, also known as coenzyme Q10 (CoQ10), is a lipid-soluble benzoquinone that plays a crucial role in the mitochondrial electron transport chain as an essential component of Complexes I, II, and III. It functions as an electron carrier, assisting in the transfer of electrons from reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FADH2) to molecular oxygen during oxidative phosphorylation, thereby contributing to the generation of adenosine triphosphate (ATP), the primary energy currency of the cell.
Additionally, ubiquinone acts as a potent antioxidant in both membranes and lipoproteins, protecting against lipid peroxidation and oxidative damage to proteins and DNA. Its antioxidant properties stem from its ability to donate electrons and regenerate other antioxidants like vitamin E. Ubiquinone is synthesized endogenously in all human cells, with the highest concentrations found in tissues with high energy demands, such as the heart, liver, kidneys, and skeletal muscles.
Deficiency in ubiquinone can result from genetic disorders, aging, or certain medications (such as statins), leading to impaired mitochondrial function and increased oxidative stress. Supplementation with ubiquinone has been explored as a potential therapeutic strategy for various conditions associated with mitochondrial dysfunction and oxidative stress, including cardiovascular diseases, neurodegenerative disorders, and cancer.
Herbicides are a type of pesticide used to control or kill unwanted plants, also known as weeds. They work by interfering with the growth processes of the plant, such as inhibiting photosynthesis, disrupting cell division, or preventing the plant from producing certain essential proteins.
Herbicides can be classified based on their mode of action, chemical composition, and the timing of their application. Some herbicides are selective, meaning they target specific types of weeds while leaving crops unharmed, while others are non-selective and will kill any plant they come into contact with.
It's important to use herbicides responsibly and according to the manufacturer's instructions, as they can have negative impacts on the environment and human health if not used properly.
Thioredoxin-disulfide reductase (Txnrd, TrxR) is an enzyme that belongs to the pyridine nucleotide-disulfide oxidoreductase family. It plays a crucial role in maintaining the intracellular redox balance by reducing disulfide bonds in proteins and keeping them in their reduced state. This enzyme utilizes NADPH as an electron donor to reduce thioredoxin (Trx), which then transfers its electrons to various target proteins, thereby regulating their activity, protein folding, and antioxidant defense mechanisms.
Txnrd is essential for several cellular processes, including DNA synthesis, gene expression, signal transduction, and protection against oxidative stress. Dysregulation of Txnrd has been implicated in various pathological conditions, such as cancer, neurodegenerative diseases, and inflammatory disorders. Therefore, understanding the function and regulation of this enzyme is of great interest for developing novel therapeutic strategies.
Reperfusion injury is a complex pathophysiological process that occurs when blood flow is restored to previously ischemic tissues, leading to further tissue damage. This phenomenon can occur in various clinical settings such as myocardial infarction (heart attack), stroke, or peripheral artery disease after an intervention aimed at restoring perfusion.
The restoration of blood flow leads to the generation of reactive oxygen species (ROS) and inflammatory mediators, which can cause oxidative stress, cellular damage, and activation of the immune system. This results in a cascade of events that may lead to microvascular dysfunction, capillary leakage, and tissue edema, further exacerbating the injury.
Reperfusion injury is an important consideration in the management of ischemic events, as interventions aimed at restoring blood flow must be carefully balanced with potential harm from reperfusion injury. Strategies to mitigate reperfusion injury include ischemic preconditioning (exposing the tissue to short periods of ischemia before a prolonged ischemic event), ischemic postconditioning (applying brief periods of ischemia and reperfusion after restoring blood flow), remote ischemic preconditioning (ischemia applied to a distant organ or tissue to protect the target organ), and pharmacological interventions that scavenge ROS, reduce inflammation, or improve microvascular function.
Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.
Bacterial proteins can be classified into different categories based on their function, such as:
1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.
Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.
Hyperglycemia is a medical term that refers to an abnormally high level of glucose (sugar) in the blood. Fasting hyperglycemia is defined as a fasting blood glucose level greater than or equal to 126 mg/dL (milligrams per deciliter) on two separate occasions. Alternatively, a random blood glucose level greater than or equal to 200 mg/dL in combination with symptoms of hyperglycemia (such as increased thirst, frequent urination, blurred vision, and fatigue) can also indicate hyperglycemia.
Hyperglycemia is often associated with diabetes mellitus, a chronic metabolic disorder characterized by high blood glucose levels due to insulin resistance or insufficient insulin production. However, hyperglycemia can also occur in other conditions such as stress, surgery, infection, certain medications, and hormonal imbalances.
Prolonged or untreated hyperglycemia can lead to serious complications such as diabetic ketoacidosis (DKA), hyperosmolar hyperglycemic state (HHS), and long-term damage to various organs such as the eyes, kidneys, nerves, and blood vessels. Therefore, it is essential to monitor blood glucose levels regularly and maintain them within normal ranges through proper diet, exercise, medication, and lifestyle modifications.
Nitrates are chemical compounds that consist of a nitrogen atom bonded to three oxygen atoms (NO3-). In the context of medical science, nitrates are often discussed in relation to their use as medications or their presence in food and water.
As medications, nitrates are commonly used to treat angina (chest pain) caused by coronary artery disease. Nitrates work by relaxing and widening blood vessels, which improves blood flow and reduces the workload on the heart. Some examples of nitrate medications include nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate.
In food and water, nitrates are naturally occurring compounds that can be found in a variety of vegetables, such as spinach, beets, and lettuce. They can also be present in fertilizers and industrial waste, which can contaminate groundwater and surface water sources. While nitrates themselves are not harmful, they can be converted into potentially harmful compounds called nitrites under certain conditions, particularly in the digestive system of young children or in the presence of bacteria such as those found in unpasteurized foods. Excessive levels of nitrites can react with hemoglobin in the blood to form methemoglobin, which cannot transport oxygen effectively and can lead to a condition called methemoglobinemia.
Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.
A case-control study is an observational research design used to identify risk factors or causes of a disease or health outcome. In this type of study, individuals with the disease or condition (cases) are compared with similar individuals who do not have the disease or condition (controls). The exposure history or other characteristics of interest are then compared between the two groups to determine if there is an association between the exposure and the disease.
Case-control studies are often used when it is not feasible or ethical to conduct a randomized controlled trial, as they can provide valuable insights into potential causes of diseases or health outcomes in a relatively short period of time and at a lower cost than other study designs. However, because case-control studies rely on retrospective data collection, they are subject to biases such as recall bias and selection bias, which can affect the validity of the results. Therefore, it is important to carefully design and conduct case-control studies to minimize these potential sources of bias.
Peroxiredoxin VI (Prdx6) is an antioxidant enzyme that belongs to the peroxiredoxin family. It plays a crucial role in reducing and regulating the levels of hydrogen peroxide, lipid peroxides, and other reactive oxygen species (ROS) within cells. Prdx6 has both peroxidase and phospholipase A2 activities, which makes it unique among the peroxiredoxins. It is widely expressed in various tissues, including the lungs, liver, kidneys, and brain. In addition to its antioxidant function, Prdx6 also contributes to cellular signaling pathways, inflammation regulation, and membrane repair processes. Dysregulation of Prdx6 has been implicated in several diseases, such as cancer, neurodegenerative disorders, and lung injury.
Advanced Glycosylation End Products (AGEs) are formed through the non-enzymatic glycation and oxidative modification of proteins, lipids, and nucleic acids. This process occurs when a sugar molecule, such as glucose, binds to a protein or lipid without the regulation of an enzyme, leading to the formation of a Schiff base. This then rearranges to form a more stable ketoamine, known as an Amadori product. Over time, these Amadori products can undergo further reactions, including oxidation, fragmentation, and cross-linking, resulting in the formation of AGEs.
AGEs can alter the structure and function of proteins and lipids, leading to damage in tissues and organs. They have been implicated in the development and progression of several age-related diseases, including diabetes, atherosclerosis, kidney disease, and Alzheimer's disease. AGEs can also contribute to inflammation and oxidative stress, which can further exacerbate tissue damage.
In summary, Advanced Glycosylation End Products (AGEs) are the result of non-enzymatic glycation and oxidation of proteins, lipids, and nucleic acids, leading to structural and functional changes in tissues and organs, and contributing to the development and progression of several age-related diseases.
The Comet Assay, also known as single-cell gel electrophoresis (SCGE), is a sensitive method used to detect and measure DNA damage at the level of individual cells. The assay gets its name from the comet-like shape that formed DNA fragments migrate towards the anode during electrophoresis, creating a "tail" that represents the damaged DNA.
In this assay, cells are embedded in low melting point agarose on a microscope slide and then lysed to remove the cell membranes and histones, leaving the DNA intact. The slides are then subjected to electrophoresis under neutral or alkaline conditions, which causes the negatively charged DNA fragments to migrate out of the nucleus towards the anode. After staining with a DNA-binding dye, the slides are visualized under a fluorescence microscope and the degree of DNA damage is quantified by measuring the length and intensity of the comet "tail."
The Comet Assay is widely used in genetic toxicology to assess the genotoxic potential of chemicals, drugs, and environmental pollutants. It can also be used to measure DNA repair capacity and oxidative DNA damage.
Ethanol is the medical term for pure alcohol, which is a colorless, clear, volatile, flammable liquid with a characteristic odor and burning taste. It is the type of alcohol that is found in alcoholic beverages and is produced by the fermentation of sugars by yeasts.
In the medical field, ethanol is used as an antiseptic and disinfectant, and it is also used as a solvent for various medicinal preparations. It has central nervous system depressant properties and is sometimes used as a sedative or to induce sleep. However, excessive consumption of ethanol can lead to alcohol intoxication, which can cause a range of negative health effects, including impaired judgment, coordination, and memory, as well as an increased risk of accidents, injuries, and chronic diseases such as liver disease and addiction.
A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.
A hydroxyl radical is defined in biochemistry and medicine as an extremely reactive species, characterized by the presence of an oxygen atom bonded to a hydrogen atom (OH-). It is formed when a water molecule (H2O) is split into a hydroxide ion (OH-) and a hydrogen ion (H+) in the process of oxidation.
In medical terms, hydroxyl radicals are important in understanding free radical damage and oxidative stress, which can contribute to the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. They are also involved in the body's natural defense mechanisms against pathogens. However, an overproduction of hydroxyl radicals can cause damage to cellular components such as DNA, proteins, and lipids, leading to cell dysfunction and death.
Mitochondrial proteins are any proteins that are encoded by the nuclear genome or mitochondrial genome and are located within the mitochondria, an organelle found in eukaryotic cells. These proteins play crucial roles in various cellular processes including energy production, metabolism of lipids, amino acids, and steroids, regulation of calcium homeostasis, and programmed cell death or apoptosis.
Mitochondrial proteins can be classified into two main categories based on their origin:
1. Nuclear-encoded mitochondrial proteins (NEMPs): These are proteins that are encoded by genes located in the nucleus, synthesized in the cytoplasm, and then imported into the mitochondria through specific import pathways. NEMPs make up about 99% of all mitochondrial proteins and are involved in various functions such as oxidative phosphorylation, tricarboxylic acid (TCA) cycle, fatty acid oxidation, and mitochondrial dynamics.
2. Mitochondrial DNA-encoded proteins (MEPs): These are proteins that are encoded by the mitochondrial genome, synthesized within the mitochondria, and play essential roles in the electron transport chain (ETC), a key component of oxidative phosphorylation. The human mitochondrial genome encodes only 13 proteins, all of which are subunits of complexes I, III, IV, and V of the ETC.
Defects in mitochondrial proteins can lead to various mitochondrial disorders, which often manifest as neurological, muscular, or metabolic symptoms due to impaired energy production. These disorders are usually caused by mutations in either nuclear or mitochondrial genes that encode mitochondrial proteins.
Methionine sulfoxide reductases (MSRs) are a group of enzymes that catalyze the reduction of methionine sulfoxides back to methionine in proteins. Methionine residues in proteins can be oxidized by reactive oxygen species (ROS) or other oxidizing agents, leading to the formation of methionine sulfoxide. This modification can affect protein function and stability. MSRs play a crucial role in protecting proteins from oxidative damage and maintaining their proper function.
There are two types of MSRs, designated as MSRA and MSRB. MSRA reduces methionine-S-sulfoxides, while MSRB reduces methionine-R-sulfoxides. Both enzymes require the cofactor thioredoxin to reduce the methionine sulfoxide back to methionine. The activity of MSRs is important in various biological processes, including protein folding, stress response, and aging. Defects in MSRs have been implicated in several diseases, such as Alzheimer's disease, Parkinson's disease, and cancer.
"Maleate" is not a medical term in and of itself, but it is a chemical compound that can be found in some medications. Maleic acid or its salts (maleates) are used as a keratolytic agent in topical medications, which means they help to break down and remove dead skin cells. They can also be used as a preservative or a buffering agent in various pharmaceutical preparations.
Maleic acid is a type of organic compound known as a dicarboxylic acid, which contains two carboxyl groups. In the case of maleic acid, these carboxyl groups are located on a single carbon atom, which makes it a cis-conjugated diacid. This structural feature gives maleic acid unique chemical properties that can be useful in various pharmaceutical and industrial applications.
It's worth noting that maleic acid and its salts should not be confused with "maleate" as a gender-specific term, which refers to something related to or characteristic of males.
Transcription factors are proteins that play a crucial role in regulating gene expression by controlling the transcription of DNA to messenger RNA (mRNA). They function by binding to specific DNA sequences, known as response elements, located in the promoter region or enhancer regions of target genes. This binding can either activate or repress the initiation of transcription, depending on the properties and interactions of the particular transcription factor. Transcription factors often act as part of a complex network of regulatory proteins that determine the precise spatiotemporal patterns of gene expression during development, differentiation, and homeostasis in an organism.
Erythrocytes, also known as red blood cells (RBCs), are the most common type of blood cell in circulating blood in mammals. They are responsible for transporting oxygen from the lungs to the body's tissues and carbon dioxide from the tissues to the lungs.
Erythrocytes are formed in the bone marrow and have a biconcave shape, which allows them to fold and bend easily as they pass through narrow blood vessels. They do not have a nucleus or mitochondria, which makes them more flexible but also limits their ability to reproduce or repair themselves.
In humans, erythrocytes are typically disc-shaped and measure about 7 micrometers in diameter. They contain the protein hemoglobin, which binds to oxygen and gives blood its red color. The lifespan of an erythrocyte is approximately 120 days, after which it is broken down in the liver and spleen.
Abnormalities in erythrocyte count or function can lead to various medical conditions, such as anemia, polycythemia, and sickle cell disease.
Polyphenols are a type of phytochemical, which are naturally occurring compounds found in plant-based foods. They contain multiple phenol units and can be classified into several subgroups, including flavonoids, stilbenes, tannins, and lignans. These compounds have been studied for their potential health benefits due to their antioxidant, anti-inflammatory, and immune-modulating properties. They are found in a wide variety of foods such as fruits, vegetables, tea, wine, chocolate, and cereals.
Homeostasis is a fundamental concept in the field of medicine and physiology, referring to the body's ability to maintain a stable internal environment, despite changes in external conditions. It is the process by which biological systems regulate their internal environment to remain in a state of dynamic equilibrium. This is achieved through various feedback mechanisms that involve sensors, control centers, and effectors, working together to detect, interpret, and respond to disturbances in the system.
For example, the body maintains homeostasis through mechanisms such as temperature regulation (through sweating or shivering), fluid balance (through kidney function and thirst), and blood glucose levels (through insulin and glucagon secretion). When homeostasis is disrupted, it can lead to disease or dysfunction in the body.
In summary, homeostasis is the maintenance of a stable internal environment within biological systems, through various regulatory mechanisms that respond to changes in external conditions.
Peroxidase is a type of enzyme that catalyzes the chemical reaction in which hydrogen peroxide (H2O2) is broken down into water (H2O) and oxygen (O2). This enzymatic reaction also involves the oxidation of various organic and inorganic compounds, which can serve as electron donors.
Peroxidases are widely distributed in nature and can be found in various organisms, including bacteria, fungi, plants, and animals. They play important roles in various biological processes, such as defense against oxidative stress, breakdown of toxic substances, and participation in metabolic pathways.
The peroxidase-catalyzed reaction can be represented by the following chemical equation:
H2O2 + 2e- + 2H+ → 2H2O
In this reaction, hydrogen peroxide is reduced to water, and the electron donor is oxidized. The peroxidase enzyme facilitates the transfer of electrons between the substrate (hydrogen peroxide) and the electron donor, making the reaction more efficient and specific.
Peroxidases have various applications in medicine, industry, and research. For example, they can be used for diagnostic purposes, as biosensors, and in the treatment of wastewater and medical wastes. Additionally, peroxidases are involved in several pathological conditions, such as inflammation, cancer, and neurodegenerative diseases, making them potential targets for therapeutic interventions.
Nitric Oxide Synthase Type II (NOS2), also known as Inducible Nitric Oxide Synthase (iNOS), is an enzyme that catalyzes the production of nitric oxide (NO) from L-arginine. Unlike other isoforms of NOS, NOS2 is not constitutively expressed and its expression can be induced by various stimuli such as cytokines, lipopolysaccharides, and bacterial products. Once induced, NOS2 produces large amounts of NO, which plays a crucial role in the immune response against invading pathogens. However, excessive or prolonged production of NO by NOS2 has been implicated in various pathological conditions such as inflammation, septic shock, and neurodegenerative disorders.
In a medical context, nitrites are typically referred to as organic compounds that contain a functional group with the formula R-N=O, where R represents an alkyl or aryl group. They are commonly used in medicine as vasodilators, which means they widen and relax blood vessels, improving blood flow and lowering blood pressure.
One example of a nitrite used medically is amyl nitrite, which was previously used to treat angina pectoris, a type of chest pain caused by reduced blood flow to the heart muscle. However, its use has largely been replaced by other medications due to safety concerns and the availability of more effective treatments.
It's worth noting that inorganic nitrites, such as sodium nitrite, are also used in medicine for various purposes, including as a preservative in food and as a medication to treat cyanide poisoning. However, these compounds have different chemical properties and uses than organic nitrites.
L-Lactate Dehydrogenase (LDH) is an enzyme found in various tissues within the body, including the heart, liver, kidneys, muscles, and brain. It plays a crucial role in the process of energy production, particularly during anaerobic conditions when oxygen levels are low.
In the presence of the coenzyme NADH, LDH catalyzes the conversion of pyruvate to lactate, generating NAD+ as a byproduct. Conversely, in the presence of NAD+, LDH can convert lactate back to pyruvate using NADH. This reversible reaction is essential for maintaining the balance between lactate and pyruvate levels within cells.
Elevated blood levels of LDH may indicate tissue damage or injury, as this enzyme can be released into the circulation following cellular breakdown. As a result, LDH is often used as a nonspecific biomarker for various medical conditions, such as myocardial infarction (heart attack), liver disease, muscle damage, and certain types of cancer. However, it's important to note that an isolated increase in LDH does not necessarily pinpoint the exact location or cause of tissue damage, and further diagnostic tests are usually required for confirmation.
Oligonucleotide Array Sequence Analysis is a type of microarray analysis that allows for the simultaneous measurement of the expression levels of thousands of genes in a single sample. In this technique, oligonucleotides (short DNA sequences) are attached to a solid support, such as a glass slide, in a specific pattern. These oligonucleotides are designed to be complementary to specific target mRNA sequences from the sample being analyzed.
During the analysis, labeled RNA or cDNA from the sample is hybridized to the oligonucleotide array. The level of hybridization is then measured and used to determine the relative abundance of each target sequence in the sample. This information can be used to identify differences in gene expression between samples, which can help researchers understand the underlying biological processes involved in various diseases or developmental stages.
It's important to note that this technique requires specialized equipment and bioinformatics tools for data analysis, as well as careful experimental design and validation to ensure accurate and reproducible results.
The Heat-Shock Response is a complex and highly conserved stress response mechanism present in virtually all living organisms. It is activated when the cell encounters elevated temperatures or other forms of proteotoxic stress, such as exposure to toxins, radiation, or infectious agents. This response is primarily mediated by a group of proteins known as heat-shock proteins (HSPs) or chaperones, which play crucial roles in protein folding, assembly, transport, and degradation.
The primary function of the Heat-Shock Response is to protect the cell from damage caused by misfolded or aggregated proteins that can accumulate under stress conditions. The activation of this response leads to the rapid transcription and translation of HSP genes, resulting in a significant increase in the intracellular levels of these chaperone proteins. These chaperones then assist in the refolding of denatured proteins or target damaged proteins for degradation via the proteasome or autophagy pathways.
The Heat-Shock Response is critical for maintaining cellular homeostasis and ensuring proper protein function under stress conditions. Dysregulation of this response has been implicated in various diseases, including neurodegenerative disorders, cancer, and cardiovascular diseases.
Transgenic mice are genetically modified rodents that have incorporated foreign DNA (exogenous DNA) into their own genome. This is typically done through the use of recombinant DNA technology, where a specific gene or genetic sequence of interest is isolated and then introduced into the mouse embryo. The resulting transgenic mice can then express the protein encoded by the foreign gene, allowing researchers to study its function in a living organism.
The process of creating transgenic mice usually involves microinjecting the exogenous DNA into the pronucleus of a fertilized egg, which is then implanted into a surrogate mother. The offspring that result from this procedure are screened for the presence of the foreign DNA, and those that carry the desired genetic modification are used to establish a transgenic mouse line.
Transgenic mice have been widely used in biomedical research to model human diseases, study gene function, and test new therapies. They provide a valuable tool for understanding complex biological processes and developing new treatments for a variety of medical conditions.
"Random allocation," also known as "random assignment" or "randomization," is a process used in clinical trials and other research studies to distribute participants into different intervention groups (such as experimental group vs. control group) in a way that minimizes selection bias and ensures the groups are comparable at the start of the study.
In random allocation, each participant has an equal chance of being assigned to any group, and the assignment is typically made using a computer-generated randomization schedule or other objective methods. This process helps to ensure that any differences between the groups are due to the intervention being tested rather than pre-existing differences in the participants' characteristics.
I'm happy to help! However, it seems like there are two terms combined into one request: "Mitochondria" and "Heart." I will provide separate definitions for each.
Mitochondrion (singular) or Mitochondria (plural): These are specialized structures found in the cytoplasm of most eukaryotic cells (cells with a true nucleus), including human cells. They are often referred to as the "powerhouse" of the cell because they generate energy in the form of ATP (adenosine triphosphate) through a process called oxidative phosphorylation. Mitochondria contain their own DNA, which is distinct from the nuclear DNA, and are believed to have originated from ancient bacteria that established a symbiotic relationship with primitive eukaryotic cells.
Heart: In human anatomy, the heart is a muscular organ responsible for pumping blood throughout the body. It is located in the thoracic cavity, slightly left of the center, and is enclosed by the pericardium, a double-walled sac that provides protection and lubrication for the heart's movement. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it to the rest of the body. The heart's pumping action is regulated by electrical signals that originate in a group of specialized cardiac muscle cells called the sinoatrial node (SA node).
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), also known as Glucosephosphate Dehydrogenase, is an enzyme that plays a crucial role in cellular metabolism, particularly in the glycolytic pathway. It catalyzes the conversion of glyceraldehyde 3-phosphate (G3P) to 1,3-bisphosphoglycerate (1,3-BPG), while also converting nicotinamide adenine dinucleotide (NAD+) to its reduced form NADH. This reaction is essential for the production of energy in the form of adenosine triphosphate (ATP) during cellular respiration. GAPDH has been widely used as a housekeeping gene in molecular biology research due to its consistent expression across various tissues and cells, although recent studies have shown that its expression can vary under certain conditions.
Gene deletion is a type of mutation where a segment of DNA, containing one or more genes, is permanently lost or removed from a chromosome. This can occur due to various genetic mechanisms such as homologous recombination, non-homologous end joining, or other types of genomic rearrangements.
The deletion of a gene can have varying effects on the organism, depending on the function of the deleted gene and its importance for normal physiological processes. If the deleted gene is essential for survival, the deletion may result in embryonic lethality or developmental abnormalities. However, if the gene is non-essential or has redundant functions, the deletion may not have any noticeable effects on the organism's phenotype.
Gene deletions can also be used as a tool in genetic research to study the function of specific genes and their role in various biological processes. For example, researchers may use gene deletion techniques to create genetically modified animal models to investigate the impact of gene deletion on disease progression or development.
Quercetin is a type of flavonoid antioxidant that is found in plant foods, including leafy greens, tomatoes, berries, and broccoli. It has been studied for its potential health benefits, such as reducing inflammation, protecting against damage to cells, and helping to reduce the risk of heart disease and cancer. Quercetin is also known for its ability to stabilize mast cells and prevent the release of histamine, making it a popular natural remedy for allergies. It is available in supplement form, but it is always recommended to consult with a healthcare provider before starting any new supplement regimen.
Diquat is a herbicide that is used to control the growth of weeds and unwanted vegetation in various settings, such as agricultural land, aquatic environments, and industrial sites. It is a type of chemical known as a contact herbicide, which means that it kills plants on contact rather than being absorbed through the plant's roots and transported throughout its tissues.
Diquat works by disrupting the plant's ability to photosynthesize, or convert light energy into chemical energy. When applied to plant leaves, diquat causes the formation of free radicals, which are highly reactive molecules that can damage cell membranes and other cell structures. This leads to the death of the plant cells and ultimately the death of the entire plant.
Diquat is a fast-acting herbicide that is often used to control weeds in aquatic environments, such as ponds and lakes. It is also used in agriculture to desiccate crops before harvest, which can make them easier to harvest and reduce post-harvest losses. However, diquat can be harmful to non-target organisms, including fish, aquatic invertebrates, and beneficial insects, so it must be used carefully and in accordance with label instructions to minimize off-target impacts.
Like all pesticides, diquat is subject to regulation by government agencies such as the Environmental Protection Agency (EPA) in the United States. The EPA sets limits on the amount of diquat that can be applied to crops and other surfaces, and requires manufacturers to provide information about the potential risks and hazards associated with its use. It is important to follow all safety precautions and guidelines when using diquat or any other pesticide to protect yourself, others, and the environment.
Fibroblasts are specialized cells that play a critical role in the body's immune response and wound healing process. They are responsible for producing and maintaining the extracellular matrix (ECM), which is the non-cellular component present within all tissues and organs, providing structural support and biochemical signals for surrounding cells.
Fibroblasts produce various ECM proteins such as collagens, elastin, fibronectin, and laminins, forming a complex network of fibers that give tissues their strength and flexibility. They also help in the regulation of tissue homeostasis by controlling the turnover of ECM components through the process of remodeling.
In response to injury or infection, fibroblasts become activated and start to proliferate rapidly, migrating towards the site of damage. Here, they participate in the inflammatory response, releasing cytokines and chemokines that attract immune cells to the area. Additionally, they deposit new ECM components to help repair the damaged tissue and restore its functionality.
Dysregulation of fibroblast activity has been implicated in several pathological conditions, including fibrosis (excessive scarring), cancer (where they can contribute to tumor growth and progression), and autoimmune diseases (such as rheumatoid arthritis).
Genetic transcription is the process by which the information in a strand of DNA is used to create a complementary RNA molecule. This process is the first step in gene expression, where the genetic code in DNA is converted into a form that can be used to produce proteins or functional RNAs.
During transcription, an enzyme called RNA polymerase binds to the DNA template strand and reads the sequence of nucleotide bases. As it moves along the template, it adds complementary RNA nucleotides to the growing RNA chain, creating a single-stranded RNA molecule that is complementary to the DNA template strand. Once transcription is complete, the RNA molecule may undergo further processing before it can be translated into protein or perform its functional role in the cell.
Transcription can be either "constitutive" or "regulated." Constitutive transcription occurs at a relatively constant rate and produces essential proteins that are required for basic cellular functions. Regulated transcription, on the other hand, is subject to control by various intracellular and extracellular signals, allowing cells to respond to changing environmental conditions or developmental cues.
Two-dimensional (2D) gel electrophoresis is a type of electrophoretic technique used in the separation and analysis of complex protein mixtures. This method combines two types of electrophoresis – isoelectric focusing (IEF) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) – to separate proteins based on their unique physical and chemical properties in two dimensions.
In the first dimension, IEF separates proteins according to their isoelectric points (pI), which is the pH at which a protein carries no net electrical charge. The proteins are focused into narrow zones along a pH gradient established within a gel strip. In the second dimension, SDS-PAGE separates the proteins based on their molecular weights by applying an electric field perpendicular to the first dimension.
The separated proteins form distinct spots on the 2D gel, which can be visualized using various staining techniques. The resulting protein pattern provides valuable information about the composition and modifications of the protein mixture, enabling researchers to identify and compare different proteins in various samples. Two-dimensional gel electrophoresis is widely used in proteomics research, biomarker discovery, and quality control in protein production.
Mitochondrial DNA (mtDNA) is the genetic material present in the mitochondria, which are specialized structures within cells that generate energy. Unlike nuclear DNA, which is present in the cell nucleus and inherited from both parents, mtDNA is inherited solely from the mother.
MtDNA is a circular molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, a process that generates energy in the form of ATP. The remaining genes encode for rRNAs and tRNAs, which are necessary for protein synthesis within the mitochondria.
Mutations in mtDNA can lead to a variety of genetic disorders, including mitochondrial diseases, which can affect any organ system in the body. These mutations can also be used in forensic science to identify individuals and establish biological relationships.
Stilbenes are a type of chemical compound that consists of a 1,2-diphenylethylene backbone. They are phenolic compounds and can be found in various plants, where they play a role in the defense against pathogens and stress conditions. Some stilbenes have been studied for their potential health benefits, including their antioxidant and anti-inflammatory effects. One well-known example of a stilbene is resveratrol, which is found in the skin of grapes and in red wine.
It's important to note that while some stilbenes have been shown to have potential health benefits in laboratory studies, more research is needed to determine their safety and effectiveness in humans. It's always a good idea to talk to a healthcare provider before starting any new supplement regimen.
In situ nick-end labeling (ISEL, also known as TUNEL) is a technique used in pathology and molecular biology to detect DNA fragmentation, which is a characteristic of apoptotic cells (cells undergoing programmed cell death). The method involves labeling the 3'-hydroxyl termini of double or single stranded DNA breaks in situ (within tissue sections or individual cells) using modified nucleotides that are coupled to a detectable marker, such as a fluorophore or an enzyme. This technique allows for the direct visualization and quantification of apoptotic cells within complex tissues or cell populations.
Hepatocytes are the predominant type of cells in the liver, accounting for about 80% of its cytoplasmic mass. They play a key role in protein synthesis, protein storage, transformation of carbohydrates, synthesis of cholesterol, bile salts and phospholipids, detoxification, modification, and excretion of exogenous and endogenous substances, initiation of formation and secretion of bile, and enzyme production. Hepatocytes are essential for the maintenance of homeostasis in the body.
Advanced Oxidation Protein Products (AOPP) are a type of oxidatively modified protein that result from the action of reactive oxygen species (ROS) and other oxidizing agents. They are formed through the interaction of chlorinated oxidants, such as hypochlorous acid (HOCl), with proteins, leading to the formation of cross-links and the modification of amino acid side chains.
AOPP have been identified as markers of oxidative stress in various pathological conditions, including chronic kidney disease, diabetes, and inflammatory diseases. They have been shown to contribute to the development of vascular complications and other organ damage by promoting inflammation, oxidative stress, and cellular dysfunction.
The measurement of AOPP levels in biological samples, such as plasma or tissues, can provide valuable information about the extent of oxidative damage and the progression of diseases associated with oxidative stress. However, further research is needed to fully understand the mechanisms underlying AOPP formation and their role in disease pathogenesis.
Streptozocin is an antibiotic and antineoplastic agent, which is primarily used in the treatment of metastatic pancreatic islet cell carcinoma (a type of pancreatic cancer). It is a naturally occurring compound produced by the bacterium Streptomyces achromogenes.
Medically, streptozocin is classified as an alkylating agent due to its ability to interact with DNA and RNA, disrupting the growth and multiplication of malignant cells. However, it can also have adverse effects on non-cancerous cells, particularly in the kidneys and pancreas, leading to potential side effects such as nephrotoxicity (kidney damage) and hyperglycemia (high blood sugar).
It is essential that streptozocin be administered under the supervision of a healthcare professional, who can monitor its effectiveness and potential side effects. The drug is typically given through intravenous infusion, with the dosage and duration tailored to individual patient needs and treatment responses.
Autophagy is a fundamental cellular process that involves the degradation and recycling of damaged or unnecessary cellular components, such as proteins and organelles. The term "autophagy" comes from the Greek words "auto" meaning self and "phagy" meaning eating. It is a natural process that occurs in all types of cells and helps maintain cellular homeostasis by breaking down and recycling these components.
There are several different types of autophagy, including macroautophagy, microautophagy, and chaperone-mediated autophagy (CMA). Macroautophagy is the most well-known form and involves the formation of a double-membraned vesicle called an autophagosome, which engulfs the cellular component to be degraded. The autophagosome then fuses with a lysosome, an organelle containing enzymes that break down and recycle the contents of the autophagosome.
Autophagy plays important roles in various cellular processes, including adaptation to starvation, removal of damaged organelles, clearance of protein aggregates, and regulation of programmed cell death (apoptosis). Dysregulation of autophagy has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and infectious diseases.
Gene expression regulation in fungi refers to the complex cellular processes that control the production of proteins and other functional gene products in response to various internal and external stimuli. This regulation is crucial for normal growth, development, and adaptation of fungal cells to changing environmental conditions.
In fungi, gene expression is regulated at multiple levels, including transcriptional, post-transcriptional, translational, and post-translational modifications. Key regulatory mechanisms include:
1. Transcription factors (TFs): These proteins bind to specific DNA sequences in the promoter regions of target genes and either activate or repress their transcription. Fungi have a diverse array of TFs that respond to various signals, such as nutrient availability, stress, developmental cues, and quorum sensing.
2. Chromatin remodeling: The organization and compaction of DNA into chromatin can influence gene expression. Fungi utilize ATP-dependent chromatin remodeling complexes and histone modifying enzymes to alter chromatin structure, thereby facilitating or inhibiting the access of transcriptional machinery to genes.
3. Non-coding RNAs: Small non-coding RNAs (sncRNAs) play a role in post-transcriptional regulation of gene expression in fungi. These sncRNAs can guide RNA-induced transcriptional silencing (RITS) complexes to specific target loci, leading to the repression of gene expression through histone modifications and DNA methylation.
4. Alternative splicing: Fungi employ alternative splicing mechanisms to generate multiple mRNA isoforms from a single gene, thereby increasing proteome diversity. This process can be regulated by RNA-binding proteins that recognize specific sequence motifs in pre-mRNAs and promote or inhibit splicing events.
5. Protein stability and activity: Post-translational modifications (PTMs) of proteins, such as phosphorylation, ubiquitination, and sumoylation, can influence their stability, localization, and activity. These PTMs play a crucial role in regulating various cellular processes, including signal transduction, stress response, and cell cycle progression.
Understanding the complex interplay between these regulatory mechanisms is essential for elucidating the molecular basis of fungal development, pathogenesis, and drug resistance. This knowledge can be harnessed to develop novel strategies for combating fungal infections and improving agricultural productivity.
Cardiac myocytes are the muscle cells that make up the heart muscle, also known as the myocardium. These specialized cells are responsible for contracting and relaxing in a coordinated manner to pump blood throughout the body. They differ from skeletal muscle cells in several ways, including their ability to generate their own electrical impulses, which allows the heart to function as an independent rhythmical pump. Cardiac myocytes contain sarcomeres, the contractile units of the muscle, and are connected to each other by intercalated discs that help coordinate contraction and ensure the synchronous beating of the heart.
Epithelial cells are types of cells that cover the outer surfaces of the body, line the inner surfaces of organs and glands, and form the lining of blood vessels and body cavities. They provide a protective barrier against the external environment, regulate the movement of materials between the internal and external environments, and are involved in the sense of touch, temperature, and pain. Epithelial cells can be squamous (flat and thin), cuboidal (square-shaped and of equal height), or columnar (tall and narrow) in shape and are classified based on their location and function.
Physiological adaptation refers to the changes or modifications that occur in an organism's biological functions or structures as a result of environmental pressures or changes. These adaptations enable the organism to survive and reproduce more successfully in its environment. They can be short-term, such as the constriction of blood vessels in response to cold temperatures, or long-term, such as the evolution of longer limbs in animals that live in open environments.
In the context of human physiology, examples of physiological adaptation include:
1. Acclimatization: The process by which the body adjusts to changes in environmental conditions, such as altitude or temperature. For example, when a person moves to a high-altitude location, their body may produce more red blood cells to compensate for the lower oxygen levels, leading to improved oxygen delivery to tissues.
2. Exercise adaptation: Regular physical activity can lead to various physiological adaptations, such as increased muscle strength and endurance, enhanced cardiovascular function, and improved insulin sensitivity.
3. Hormonal adaptation: The body can adjust hormone levels in response to changes in the environment or internal conditions. For instance, during prolonged fasting, the body releases stress hormones like cortisol and adrenaline to help maintain energy levels and prevent muscle wasting.
4. Sensory adaptation: Our senses can adapt to different stimuli over time. For example, when we enter a dark room after being in bright sunlight, it takes some time for our eyes to adjust to the new light level. This process is known as dark adaptation.
5. Aging-related adaptations: As we age, various physiological changes occur that help us adapt to the changing environment and maintain homeostasis. These include changes in body composition, immune function, and cognitive abilities.
Small interfering RNA (siRNA) is a type of short, double-stranded RNA molecule that plays a role in the RNA interference (RNAi) pathway. The RNAi pathway is a natural cellular process that regulates gene expression by targeting and destroying specific messenger RNA (mRNA) molecules, thereby preventing the translation of those mRNAs into proteins.
SiRNAs are typically 20-25 base pairs in length and are generated from longer double-stranded RNA precursors called hairpin RNAs or dsRNAs by an enzyme called Dicer. Once generated, siRNAs associate with a protein complex called the RNA-induced silencing complex (RISC), which uses one strand of the siRNA (the guide strand) to recognize and bind to complementary sequences in the target mRNA. The RISC then cleaves the target mRNA, leading to its degradation and the inhibition of protein synthesis.
SiRNAs have emerged as a powerful tool for studying gene function and have shown promise as therapeutic agents for a variety of diseases, including viral infections, cancer, and genetic disorders. However, their use as therapeutics is still in the early stages of development, and there are challenges associated with delivering siRNAs to specific cells and tissues in the body.
Vasodilation is the widening or increase in diameter of blood vessels, particularly the involuntary relaxation of the smooth muscle in the tunica media (middle layer) of the arteriole walls. This results in an increase in blood flow and a decrease in vascular resistance. Vasodilation can occur due to various physiological and pathophysiological stimuli, such as local metabolic demands, neural signals, or pharmacological agents. It plays a crucial role in regulating blood pressure, tissue perfusion, and thermoregulation.
Xanthine is a purine base, which is a naturally occurring heterocyclic aromatic organic compound. It is formed in the body during the metabolism of purines, and it's a normal intermediate in the breakdown of nucleotides to uric acid. Xanthine is also found in various foods and beverages, such as coffee, tea, and chocolate. In the medical field, xanthine may refer to a class of drugs called xanthine derivatives, which include theophylline and caffeine, that act as bronchodilators and cardiac stimulants.
Atherosclerosis is a medical condition characterized by the buildup of plaques, made up of fat, cholesterol, calcium, and other substances found in the blood, on the inner walls of the arteries. This process gradually narrows and hardens the arteries, reducing the flow of oxygen-rich blood to various parts of the body. Atherosclerosis can affect any artery in the body, including those that supply blood to the heart (coronary arteries), brain, limbs, and other organs. The progressive narrowing and hardening of the arteries can lead to serious complications such as coronary artery disease, carotid artery disease, peripheral artery disease, and aneurysms, which can result in heart attacks, strokes, or even death if left untreated.
The exact cause of atherosclerosis is not fully understood, but it is believed to be associated with several risk factors, including high blood pressure, high cholesterol levels, smoking, diabetes, obesity, physical inactivity, and a family history of the condition. Atherosclerosis can often progress without any symptoms for many years, but as the disease advances, it can lead to various signs and symptoms depending on which arteries are affected. Treatment typically involves lifestyle changes, medications, and, in some cases, surgical procedures to restore blood flow.
p38 Mitogen-Activated Protein Kinases (p38 MAPKs) are a family of conserved serine-threonine protein kinases that play crucial roles in various cellular processes, including inflammation, immune response, differentiation, apoptosis, and stress responses. They are activated by diverse stimuli such as cytokines, ultraviolet radiation, heat shock, osmotic stress, and lipopolysaccharides (LPS).
Once activated, p38 MAPKs phosphorylate and regulate several downstream targets, including transcription factors and other protein kinases. This regulation leads to the expression of genes involved in inflammation, cell cycle arrest, and apoptosis. Dysregulation of p38 MAPK signaling has been implicated in various diseases, such as cancer, neurodegenerative disorders, and autoimmune diseases. Therefore, p38 MAPKs are considered promising targets for developing new therapeutic strategies to treat these conditions.
I'm sorry for any confusion, but Nitrilotriacetic Acid (NTA) is not a medical term. It is a chemical compound with the formula N(CH2CO2H)3. It's a white water-soluble solid used as a chelating agent, which can form stable complexes with various metal ions.
However, in a broader scientific context, it might be relevant to note that NTA has been used in biochemical research and medical fields for purposes such as metal ion removal or immobilization. But it's not a term that would typically be used in a patient-facing medical context.
Metallothioneins (MTs) are a group of small, cysteine-rich, metal-binding proteins found in the cells of many organisms, including humans. They play important roles in various biological processes such as:
1. Metal homeostasis and detoxification: MTs can bind to various heavy metals like zinc, copper, cadmium, and mercury with high affinity. This binding helps regulate the concentration of these metals within cells and protects against metal toxicity.
2. Oxidative stress protection: Due to their high cysteine content, MTs act as antioxidants by scavenging reactive oxygen species (ROS) and free radicals, thus protecting cells from oxidative damage.
3. Immune response regulation: MTs are involved in the modulation of immune cell function and inflammatory responses. They can influence the activation and proliferation of immune cells, as well as the production of cytokines and chemokines.
4. Development and differentiation: MTs have been implicated in cell growth, differentiation, and embryonic development, particularly in tissues with high rates of metal turnover, such as the liver and kidneys.
5. Neuroprotection: In the brain, MTs play a role in protecting neurons from oxidative stress, excitotoxicity, and heavy metal toxicity. They have been implicated in various neurodegenerative disorders, including Alzheimer's and Parkinson's diseases.
There are four main isoforms of metallothioneins (MT-1, MT-2, MT-3, and MT-4) in humans, each with distinct tissue expression patterns and functions.
Glucose oxidase (GOD) is an enzyme that catalyzes the oxidation of D-glucose to D-glucono-1,5-lactone, while reducing oxygen to hydrogen peroxide in the process. This reaction is a part of the metabolic pathway in some organisms that convert glucose into energy. The systematic name for this enzyme is D-glucose:oxygen 1-oxidoreductase.
Glucose oxidase is commonly found in certain fungi, such as Aspergillus niger, and it has various applications in industry, medicine, and research. For instance, it's used in the production of glucose sensors for monitoring blood sugar levels, in the detection and quantification of glucose in food and beverages, and in the development of biosensors for environmental monitoring.
It's worth noting that while glucose oxidase has many applications, it should not be confused with glutathione peroxidase, another enzyme involved in the reduction of hydrogen peroxide to water.
Blood pressure is the force exerted by circulating blood on the walls of the blood vessels. It is measured in millimeters of mercury (mmHg) and is given as two figures:
1. Systolic pressure: This is the pressure when the heart pushes blood out into the arteries.
2. Diastolic pressure: This is the pressure when the heart rests between beats, allowing it to fill with blood.
Normal blood pressure for adults is typically around 120/80 mmHg, although this can vary slightly depending on age, sex, and other factors. High blood pressure (hypertension) is generally considered to be a reading of 130/80 mmHg or higher, while low blood pressure (hypotension) is usually defined as a reading below 90/60 mmHg. It's important to note that blood pressure can fluctuate throughout the day and may be affected by factors such as stress, physical activity, and medication use.
Hormesis is a term used in medicine and toxicology to describe a biphasic dose response to a chemical or physical agent, where low doses induce a beneficial effect and high doses cause harm. It was first introduced in 1943 by biologist Antonius Van den Bergh.
In other words, hormesis describes the phenomenon where a substance that is toxic or harmful at high levels can have a stimulatory or protective effect at lower levels. This concept has been observed in various biological systems and across different species, including humans. The exact mechanisms behind hormesis are not fully understood, but it's believed to be related to the activation of stress response pathways that promote cellular protection and repair.
Examples of hormetic substances include some plant-derived compounds like resveratrol, found in grapes and red wine, which has been shown to have beneficial effects on cardiovascular health at low doses but can be toxic at high doses. Similarly, exposure to low levels of radiation has been suggested to stimulate DNA repair mechanisms, while high levels can cause damage and increase the risk of cancer.
It's important to note that hormesis is a complex phenomenon, and its application in medicine and public health remains controversial. Further research is needed to fully understand the underlying mechanisms and potential therapeutic applications of hormetic substances.
Tumor Necrosis Factor-alpha (TNF-α) is a cytokine, a type of small signaling protein involved in immune response and inflammation. It is primarily produced by activated macrophages, although other cell types such as T-cells, natural killer cells, and mast cells can also produce it.
TNF-α plays a crucial role in the body's defense against infection and tissue injury by mediating inflammatory responses, activating immune cells, and inducing apoptosis (programmed cell death) in certain types of cells. It does this by binding to its receptors, TNFR1 and TNFR2, which are found on the surface of many cell types.
In addition to its role in the immune response, TNF-α has been implicated in the pathogenesis of several diseases, including autoimmune disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, as well as cancer, where it can promote tumor growth and metastasis.
Therapeutic agents that target TNF-α, such as infliximab, adalimumab, and etanercept, have been developed to treat these conditions. However, these drugs can also increase the risk of infections and other side effects, so their use must be carefully monitored.
The aorta is the largest artery in the human body, which originates from the left ventricle of the heart and carries oxygenated blood to the rest of the body. It can be divided into several parts, including the ascending aorta, aortic arch, and descending aorta. The ascending aorta gives rise to the coronary arteries that supply blood to the heart muscle. The aortic arch gives rise to the brachiocephalic, left common carotid, and left subclavian arteries, which supply blood to the head, neck, and upper extremities. The descending aorta travels through the thorax and abdomen, giving rise to various intercostal, visceral, and renal arteries that supply blood to the chest wall, organs, and kidneys.
DNA fragmentation is the breaking of DNA strands into smaller pieces. This process can occur naturally during apoptosis, or programmed cell death, where the DNA is broken down and packaged into apoptotic bodies to be safely eliminated from the body. However, excessive or abnormal DNA fragmentation can also occur due to various factors such as oxidative stress, exposure to genotoxic agents, or certain medical conditions. This can lead to genetic instability, cellular dysfunction, and increased risk of diseases such as cancer. In the context of reproductive medicine, high levels of DNA fragmentation in sperm cells have been linked to male infertility and poor assisted reproductive technology outcomes.
The crystalline lens is a biconvex transparent structure in the eye that helps to refract (bend) light rays and focus them onto the retina. It is located behind the iris and pupil and is suspended by small fibers called zonules that connect it to the ciliary body. The lens can change its shape to accommodate and focus on objects at different distances, a process known as accommodation. With age, the lens may become cloudy or opaque, leading to cataracts.
Hypertension is a medical term used to describe abnormally high blood pressure in the arteries, often defined as consistently having systolic blood pressure (the top number in a blood pressure reading) over 130 mmHg and/or diastolic blood pressure (the bottom number) over 80 mmHg. It is also commonly referred to as high blood pressure.
Hypertension can be classified into two types: primary or essential hypertension, which has no identifiable cause and accounts for about 95% of cases, and secondary hypertension, which is caused by underlying medical conditions such as kidney disease, hormonal disorders, or use of certain medications.
If left untreated, hypertension can lead to serious health complications such as heart attack, stroke, heart failure, and chronic kidney disease. Therefore, it is important for individuals with hypertension to manage their condition through lifestyle modifications (such as healthy diet, regular exercise, stress management) and medication if necessary, under the guidance of a healthcare professional.
Body weight is the measure of the force exerted on a scale or balance by an object's mass, most commonly expressed in units such as pounds (lb) or kilograms (kg). In the context of medical definitions, body weight typically refers to an individual's total weight, which includes their skeletal muscle, fat, organs, and bodily fluids.
Healthcare professionals often use body weight as a basic indicator of overall health status, as it can provide insights into various aspects of a person's health, such as nutritional status, metabolic function, and risk factors for certain diseases. For example, being significantly underweight or overweight can increase the risk of developing conditions like malnutrition, diabetes, heart disease, and certain types of cancer.
It is important to note that body weight alone may not provide a complete picture of an individual's health, as it does not account for factors such as muscle mass, bone density, or body composition. Therefore, healthcare professionals often use additional measures, such as body mass index (BMI), waist circumference, and blood tests, to assess overall health status more comprehensively.
Nerve degeneration, also known as neurodegeneration, is the progressive loss of structure and function of neurons, which can lead to cognitive decline, motor impairment, and various other symptoms. This process occurs due to a variety of factors, including genetics, environmental influences, and aging. It is a key feature in several neurological disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. The degeneration can affect any part of the nervous system, leading to different symptoms depending on the location and extent of the damage.
Neurodegenerative diseases are a group of disorders characterized by progressive and persistent loss of neuronal structure and function, often leading to cognitive decline, functional impairment, and ultimately death. These conditions are associated with the accumulation of abnormal protein aggregates, mitochondrial dysfunction, oxidative stress, chronic inflammation, and genetic mutations in the brain. Examples of neurodegenerative diseases include Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic Lateral Sclerosis (ALS), and Spinal Muscular Atrophy (SMA). The underlying causes and mechanisms of these diseases are not fully understood, and there is currently no cure for most neurodegenerative disorders. Treatment typically focuses on managing symptoms and slowing disease progression.
Cell respiration is the process by which cells convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The three main stages of cell respiration are glycolysis, the citric acid cycle (also known as the Krebs cycle), and the electron transport chain.
During glycolysis, which takes place in the cytoplasm, glucose is broken down into two molecules of pyruvate, producing a small amount of ATP and reducing power in the form of NADH.
The citric acid cycle occurs in the mitochondria and involves the breakdown of acetyl-CoA (formed from pyruvate) to produce more ATP, NADH, and FADH2.
Finally, the electron transport chain, also located in the mitochondria, uses the energy from NADH and FADH2 to pump protons across the inner mitochondrial membrane, creating a proton gradient. The flow of protons back across the membrane drives the synthesis of ATP, which is used as a source of energy by the cell.
Cell respiration is a crucial process that allows cells to generate the energy they need to perform various functions and maintain homeostasis.
Down-regulation is a process that occurs in response to various stimuli, where the number or sensitivity of cell surface receptors or the expression of specific genes is decreased. This process helps maintain homeostasis within cells and tissues by reducing the ability of cells to respond to certain signals or molecules.
In the context of cell surface receptors, down-regulation can occur through several mechanisms:
1. Receptor internalization: After binding to their ligands, receptors can be internalized into the cell through endocytosis. Once inside the cell, these receptors may be degraded or recycled back to the cell surface in smaller numbers.
2. Reduced receptor synthesis: Down-regulation can also occur at the transcriptional level, where the expression of genes encoding for specific receptors is decreased, leading to fewer receptors being produced.
3. Receptor desensitization: Prolonged exposure to a ligand can lead to a decrease in receptor sensitivity or affinity, making it more difficult for the cell to respond to the signal.
In the context of gene expression, down-regulation refers to the decreased transcription and/or stability of specific mRNAs, leading to reduced protein levels. This process can be induced by various factors, including microRNA (miRNA)-mediated regulation, histone modification, or DNA methylation.
Down-regulation is an essential mechanism in many physiological processes and can also contribute to the development of several diseases, such as cancer and neurodegenerative disorders.
Oxidative stress
Oxidative phosphorylation
Helmut Sies
Cortisol
Aging brain
Advanced glycation end-product
Obligate aerobe
Biological psychiatry
Rajiv Ratan
Hypoxia (environmental)
Telomeres in the cell cycle
Alcohol and cancer
Metabolism
Glutathione synthetase
Periodontal disease
List of epidemics and pandemics
Phosphogluconate dehydrogenase (decarboxylating)
Antioxidant
Hormesis
Asthma
Pro-oxidant
Drug metabolism
Ataxia-telangiectasia
Doris Abele
Premature greying of hair
Oxygen radical absorbance capacity
3-Deoxyglucosone
Frenolicin B
Hemopexin family
Ergothioneine
Oxidative stress - Wikipedia
Role of oxidative stress in female reproduction
Full-genome CRISPR screen reveals surprising ways neurons survive oxidative stress | ScienceDaily
Targeting Early Atherosclerosis: A Focus on Oxidative Stress and Inflammation
Zinc and its effects on oxidative stress in Alzheimer's disease | SpringerLink
Oxidative Stress - Glossary Definition
Oxidative Stress in the Critically Ill Patients: Pathophysiology and Potential Interventions | Hindawi
Excitotoxic inactivation of constitutive oxidative stress detoxification pathway in neurons can be rescued by PKD1 | Nature...
Frontiers | Atrazine: cytotoxicity, oxidative stress, apoptosis, testicular effects and chemopreventive Interventions
Antioxidants | Free Full-Text | Neopterin, Inflammation, and Oxidative Stress: What Could We Be Missing?
4-Hydroxy-2-nonenal: a product and mediator of oxidative stress
Oxidative Stress Tests - Integrative Psychiatry
Relevance of oxidative stress - ECETOC
Identification and validation of oxidative stress and immune-related hub genes in Alzheimer's disease through bioinformatics...
Ethnopharmacological approaches in mood and anxiety disorders. The relevance of the oxidative stress status
Chaparral herb found to prevent oral diseases caused by oxidative stress - NaturalNews.com
UBIRA ETheses - Oxidative stress biomarkers in dementia
Lemon Peel and Oxidative Stress - Limoneira
Oxidative Stress DOJINDO LABORATORIES
Antioxidants | Free Full-Text | NADPH Oxidase Mediates Oxidative Stress and Ventricular Remodeling through SIRT3/FOXO3a Pathway...
Molecular Vision: Neuroprotective and neurite outgrowth effects of maltol on retinal ganglion cells under oxidative stress
JCI - Chop deletion reduces oxidative stress, improves β cell function, and promotes cell survival in multiple mouse models of...
Pharmawire: Medivation, Anavex May Lower Oxidative Stress
Studying oxidative stress and skin aging - PromoCell
Using Fluorescence Derivatization and Analytical Separations to Investigate Biomarkers of Oxidative Stress
What thyroid patients should know about Oxidative Stress - Stop The Thyroid Madness
PRIME PubMed | Dual effects of antioxidants in neurodegeneration: direct neuroprotection against oxidative stress and indirect...
Citations: Relationship Between Oxidative Stress Production and Virulence Capacity of Entamoeba Strains
MicroRNA‑132 promotes oxidative stress‑induced pyroptosis by targeting sirtuin 1 in myocardial ischaemia‑reperfusion injury
Synergistic effect of co-exposure to carbon black and Fe2O3 nanoparticles on oxidative stress in cultured lung epithelial cells...
Levels of oxidative stress4
- However, under the severe levels of oxidative stress that cause necrosis, the damage causes ATP depletion, preventing controlled apoptotic death and causing the cell to simply fall apart. (wikipedia.org)
- Among the most interesting of his findings was that switching off the gene for a protein called prosaposin, which normally assists with the cell's recycling of waste products, greatly increased the levels of oxidative stress. (sciencedaily.com)
- The evidence thus far suggests that increased levels of oxidative stress and vascular risk factors are two major contributors, amongst others, to AD development. (bham.ac.uk)
- Paternal obesity is a particularly frequent example and age, too, has been found to be associated with elevated levels of oxidative stress, alterations in methylation status and increased risk of neurological disorders - epigenetics! (my-fertility-blog.com)
Reactive oxygen9
- Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. (wikipedia.org)
- Production of reactive oxygen species is a particularly destructive aspect of oxidative stress. (wikipedia.org)
- Increasing evidence suggests that the etiology of AD may involve disruptions of zinc homeostasis, and oxidative stress facilitating reactive oxygen species production is an early and sustained event in AD disease progression. (springer.com)
- The formation of reactive oxygen species, the damage caused by them in various tissues, the role of inflammatory mediators or enzymatic scavengers in oxidative stress pathogenesis, and the loss of integrity of antioxidant defense systems have been documented in different aspects of the critical illness. (hindawi.com)
- Although oxygen itself is an essential element of life, molecules in cells, such as DNA and proteins, are sometimes damaged by reactive oxygen species (ROS) in what is called oxidative stress. (dojindo.com)
- Oxidative stress, in which production of highly reactive oxygen species (ROS) and reactive nitrogen species (RNS) overwhelms antioxidant defenses, is a feature of many neurological diseases and neurodegeneration. (unboundmedicine.com)
- Glutathione serves as an antioxidant and protects against oxidative damage, but it can also bond covalently with proteins via its sulfhydryl moiety in the presence of reactive oxygen species (ROS). (huntingtree.co.nz)
- When plant cells surpass stress threshold stimuli, chemically reactive oxygen species (ROS) are generated that can cause oxidative damage or act as signals. (lincoln.ac.uk)
- Human alveolar lung A459 epithelial cells were exposed to freshly generated metal NP mixtures at a target concentration of 100?µg/m3 for 6?hr and then harvested for assessment of cytotoxicity, generation of reactive oxygen species (ROS), and alterations in the expression of genes and proteins involved in metal regulation, inflammatory responses, and oxidative stress. (cdc.gov)
Mitochondrial Dysfunction3
- Aβ-mediated oxidative stress results in mitochondrial dysfunction, impairment of glucose metabolism, loss of proteostasis and synaptic plasticity, altered signal transduction, neuroinflammation, and progressive loss of neurons 9 . (nature.com)
- Oxidative stress and mitochondrial dysfunction are important mechanisms of ventricular remodeling, predisposed to the development of diabetic cardiomyopathy (DCM) in type 2 diabetes mellitus. (mdpi.com)
- there is a change in metabolism early on in AD patients - which implicates mitochondrial dysfunction and oxidative stress. (anavex.com)
Reversing oxidative stress induced1
- Based on the results of their experiment, the researchers concluded that the aqueous extract of L. divaricata is capable of reversing oxidative stress induced by the administration of STZ in the submandibular glands of rats. (naturalnews.com)
Marker of oxidative stress2
- G SNP, a marker of oxidative stress (NAD[P]H quinone oxidoreductase mRNA) and homeostasis model assessment of insulin resistance. (diabetesjournals.org)
- Therefore, glutathione adducts can serve as a stable marker of oxidative stress in proteins. (huntingtree.co.nz)
Markers of oxidative stress3
- While many of these products are used as markers of oxidative stress, the products derived from linoleic acid appear far more predominant than arachidonic acid products and therefore easier to identify and quantify in, for example, atheromatous plaques. (wikipedia.org)
- The thesis aimed to investigate markers of oxidative stress in AD plasma. (bham.ac.uk)
- In view of all the aforementioned, the objective of the present work was to make a comparative analysis of the protective effects derivable from riboflavin (B 2 ) and pyridoxine (B 6 ) on 5-HIAA and dopamine levels, as well as on selected markers of oxidative stress in rats' brain regions after an induction of Huntington's disease (HD). (biomedcentral.com)
Apoptosis10
- However, more severe oxidative stress can cause cell death, and even moderate oxidation can trigger apoptosis, while more intense stresses may cause necrosis. (wikipedia.org)
- However, oxidative stress could play salient role in the observed cellular and genetic toxicity and apoptosis-like effects which could be abrogated by antioxidant vitamins and flavonoids, including vitamin E, quercetin, kolaviron, myricetin and bioactive extractives with antioxidant effects. (frontiersin.org)
- Under oxidative stress, the effects of maltol on cell viability, apoptosis, and neurite outgrowth were assessed. (molvis.org)
- Chronic ER stress promotes apoptosis, at least in part through the UPR-induced transcription factor C/EBP homologous protein (CHOP). (jci.org)
- These findings suggest that CHOP is a fundamental factor that links protein misfolding in the ER to oxidative stress and apoptosis in β cells under conditions of increased insulin demand. (jci.org)
- Myocardial I/R injury may induce cell apoptosis and autophagy by activating oxidative stress and upregulating inflammatory mediators, ultimately resulting in irreversible fibrotic damage ( 3 ). (spandidos-publications.com)
- In this study, we examined the cytoprotective effects of cyanidin-3-glucoside (C3G) isolated from mulberry fruit against pancreatic β-cell apoptosis caused by hydrogen peroxide (H2O2)-induced oxidative stress. (spandidos-publications.com)
- The MIN6 pancreatic β-cells were used to investigate the cytoprotective effects of C3G on the oxidative stress-induced apoptosis of cells. (spandidos-publications.com)
- Taken together, our results suggest that C3G isolated from mulberry fruit has potential for use as a phytotherapeutic agent for the prevention of diabetes by preventing oxidative stress-induced β-cell apoptosis. (spandidos-publications.com)
- Taken together, our study demonstrated that GO-AgNPs potentially induce oxidative damage to DNA, which result in toxicity and cell apoptosis in caprine fetal fibroblast cell due to an increased generation of ROS. (researchsquare.com)
Inflammation15
- Therefore, with the aim to summarize the current knowledge on the initiation of the atherosclerotic process, in this paper, we review the early markers of atherosclerosis and we address the main therapeutic targets for preventing atheroma formation at its very initial stages focusing on inflammation, oxidative stress, endothelial dysfunction, and the interaction between platelets and endothelium. (hindawi.com)
- The sugars lactose and galactose that are found in milk can increase oxidative stress and chronic inflammation in the body - both of which are major causes of serious and chronic diseases. (diagnose-me.com)
- Neopterin, Inflammation, and Oxidative Stress: What Could We Be Missing? (mdpi.com)
- Neopterin has been extensively used as a clinical marker of immune activation during inflammation in a wide range of conditions and stresses. (mdpi.com)
- Oxidative stress results from an imbalance of pro- and anti-oxidants and leads to faster skin aging, inflammation and disease. (promocell.com)
- Oxidative stress can become a self-fuelling cycle, where the initial stress leads to dysregulation of physiological processes, inflammation and a deregulated immune system which in turn lead to various diseases that may cause further inflammation and oxidative stress. (promocell.com)
- This thesis details analytical methods that use fluorescence derivatization in order to detect small molecule biomarkers of oxidative stress as they relate to epilepsy, inflammation, and traumatic brain injury. (ku.edu)
- A microchip electrophoresis-fluorescence method was then developed for the detection of carnosine, an endogenous dipeptide that is involved in oxidative stress-induced inflammation following prolonged activation of macrophage cells. (ku.edu)
- Moreover, oxidative stress also activates mechanisms that result in a glia-mediated inflammation that also causes secondary neuronal damage. (unboundmedicine.com)
- We provide biomedical researchers with the best tools available for the analysis of Oxidative Stress and Chronic Inflammation - two of the most important risk factors that play key roles in the development of a wide range of human illness, including cancer, cardiovascular disease, diabetes and neurodegeneration. (oxfordbiomed.com)
- After two weeks of intermittent oxygen deprivation, all animals were tested for learning, oxidative stress, and inflammation. (green-tea-health-news.com)
- Those receiving water only showed a loss of learning in a maze test, as well as markedly increased oxidative stress and inflammation. (green-tea-health-news.com)
- it reduced both oxidative stress and inflammation, up to 40% in some cases (Burckhardt JC, Green tea catechin polyphenols attenuate behavioral and oxidative responses to intermittent hyposia, American Journal of Respiratory and Critical Care Medicine, May 2008). (green-tea-health-news.com)
- Two prominent welding fume particulate metal components are nanosized iron (Fe) and manganese (Mn) which might induce oxidative stress and inflammation resulting in pulmonary injury. (cdc.gov)
- Assessment of gene expression demonstrated variable up-regulation in cellular mechanisms related to metal transport and storage, inflammation, and oxidative stress based upon aerosol composition. (cdc.gov)
Associated with increased oxidative stress2
- Cosmic radiation is known to induce DNA and lipid damage associated with increased oxidative stress and remains a major concern in space travel. (drsircus.com)
- Oxidative stress during pregnancy alters fetal epigenetic patterns and leads to cardiovascular disease and maternal diabetes (associated with increased oxidative stress) increases the risk of autism disorders in children - epigenetics! (my-fertility-blog.com)
Free radicals4
- It is well known that an excessive production of free radicals contributes to an increased burden of oxidative stress that may be implicated in the pathophysiology of tissue injury of various organs and in systemic dysfunction in critically ill patients. (hindawi.com)
- Research suggests aging is caused by cumulative oxidative stress due to free radicals generated in biological systems both via metabolism and as a result of exposure to UV light (Stojiljkovic, 2014). (promocell.com)
- Oxidative stress is essentially an imbalance between the production of free radicals and the ability of the body to counteract or detoxify their harmful effects through neutralization by antioxidants. (my-fertility-blog.com)
- The aim of this work was to determine if riboflavin (B 2 ) and pyridoxine (B 6 ) provide protection to the brain against free radicals generated by 3-nitropropionic acid (3-NPA) by measuring the levels of dopamine (DA) and selected oxidative stress markers. (biomedcentral.com)
Imbalance3
- STZ has been shown to generate an imbalance between oxidative and antioxidant systems by decreasing the secretion of peroxidase in submandibular glands. (naturalnews.com)
- Oxidative modifications are a hallmark of oxidative imbalance in the brains of individuals with AD, according to one paper by Smith. (anavex.com)
- Oxidative stress is commonly defined as an imbalance between pro- and antioxidants (Tan, 2018). (promocell.com)
Lipids2
- Lipids, proteins, carbohydrates and DNA are all susceptible to oxidative damage and this damage can change gene transcription along with cell proliferation and differentiation and is involved in several diseases including diabetes and obesity, cancer and neurological disorders (Kregel, 2007). (promocell.com)
- Saleh R, Betancor M, Roo J, Benitez-Santana T, Zamorano MJ & Izquierdo MS (2015) Biomarkers of bone development and oxidative stress in gilthead seabream larvae fed microdiets with several levels of polar lipids and α-tocopherol. (stir.ac.uk)
Proteins6
- Moreover, the oxidative status of specific proteins was investigated using both hypothesis driven and proteomic approaches. (bham.ac.uk)
- Results presented in this thesis suggest that global plasma protein oxidation levels are not different when AD and control subjects are compared, but that individual plasma proteins are specific targets for oxidative modification in AD. (bham.ac.uk)
- UV radiation that causes oxidative stress and hence aging induces the expression of matrix metalloproteinases (MMPs) that degrade dermal collagen and other proteins from the extracellular matrix (Caravalhaes Lago, 2019). (promocell.com)
- ROS and RNS can also indirectly contribute to tissue damage by activating a number of cellular pathways resulting in the expression of stress-sensitive genes and proteins to cause oxidative injury. (unboundmedicine.com)
- The levels of peroxisome proliferator‑activated receptor gamma coactivator (PGC)‑1α/nuclear factor erythroid‑2‑related factor 2 (Nrf2) signalling, oxidative stress and pyroptosis‑related proteins were detected by western blotting. (spandidos-publications.com)
- Inhibition of miR‑132 activated PGC‑1α/Nrf2 signalling and inhibited oxidative stress and the expression of the pyroptosis‑related proteins NLRP3, caspase‑1 and IL‑1β, which were all reversed by inhibiting SIRT1 with EX527. (spandidos-publications.com)
Dysfunction4
- Atherosclerosis is a chronic vascular inflammatory disease associated to oxidative stress and endothelial dysfunction. (hindawi.com)
- Here we investigate the effect of EUK-134, a synthetic superoxide dismutase and catalase mimetic, (i) on renal dysfunction and injury caused by I/R in vivo and (ii) on proximal tubular cell (PTC) injury and death caused by oxidative and nitrosative stress. (scienceopen.com)
- The findings emphasize the role of concomitant oxidative and nitrosative stress and the role of peroxynitrite in the ensuing renal dysfunction. (scienceopen.com)
- Project 2 examines the hypothesis that A13-mediated oxidative modifications of and subsequent dysfunction of Pini are fundamental to the genesis of specific pathological features in AD. (uky.edu)
Role of oxidative stress1
- The review comprehensively explores the literature for evidence of the role of oxidative stress in conditions such as abortions, preeclampsia, hydatidiform mole, fetal embryopathies, preterm labour and preeclampsia and gestational diabetes. (nih.gov)
Assays for oxidative stress1
- Our major goal is to provide you with straightforward, reliable assays for oxidative stress biomarkers and for antioxidant capacity of biological fluids. (oxfordbiomed.com)
Effects of oxidative stress2
- The effects of oxidative stress depend upon the size of these changes, with a cell being able to overcome small perturbations and regain its original state. (wikipedia.org)
- there is no definitive study which has shown that maltol effectively protects them from the devastating effects of oxidative stress. (molvis.org)
Biomarkers of oxidative stress1
- Using isoprostanes as biomarkers of oxidative stress: some rarely considered issues. (degruyter.com)
Regulation of oxidative stress2
- Furthermore, the impact of several drugs and treatments on the regulation of oxidative stress in critically ill patients has been evaluated in several investigations aiming to improve outcomes in critical illness. (hindawi.com)
- The regulation of oxidative stress in the different cells is associated with the enzymatic activity of antioxidant systems related to zinc (Zn) and selenium (Se) elements. (ualg.pt)
Mechanisms14
- Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling. (wikipedia.org)
- An intense study of the underlying mechanisms and interventions related to oxidative stress could provide further insight into the understanding of critical illness and could form the basis for novel strategic hypothesis or improved interventions in the management of critically ill patients. (hindawi.com)
- We therefore invite authors to contribute original research articles as well as review articles that will stimulate the effort to understand thoroughly the underlying mechanisms of oxidative stress, to reveal its impact on major organs and systems, and to illustrate diagnostic and treatment interventions in the critically ill patient. (hindawi.com)
- Excitotoxicity, a critical process in neurodegeneration, induces oxidative stress and neuronal death through mechanisms largely unknown. (nature.com)
- In response, aerobic organisms created defense mechanisms to avoid oxidative stress. (dojindo.com)
- Oxidative stress has recently become the focus of many studies seeking to understand these defense mechanisms and the relationships between oxidative damage and disease or aging processes. (dojindo.com)
- Measurement of these modifications is important for understanding the mechanisms of oxidative DNA damage and its biological repercussions. (dojindo.com)
- It is designed to protect against outside damage including UV light exposure and has several defense mechanisms to protect against oxidative damage including antioxidants such as superoxide dismutases, CGT, catalases, GSH and ascorbic acid. (promocell.com)
- A clearer appreciation of the potential therapeutic utility of antioxidants would emerge only when the complexity of their effects on mechanisms that interact to determine the extent of oxidative damage in vivo are more fully defined and understood. (unboundmedicine.com)
- Assays for some of these oxidative stress biomarkers, as well as assays for several of the body's antioxidant defense mechanisms, have been widely used. (oxfordbiomed.com)
- Scholars@Duke publication: Mechanisms of resistance to oxidative and nitrosative stress: implications for fungal survival in mammalian hosts. (duke.edu)
- The major hypothesis of this application is that betaamyloid peptide (Af3) is one of the pivotal mechanisms in oxidative stress/damage to neurons in AD. (uky.edu)
- This well integrated program project will move the field of A13 and oxidative stress in AD forward and gain insights into mechanisms of neuron degeneration so that successful interventions can be developed to treat or prevent the most dehumanizing disorder to affect humans. (uky.edu)
- Mechanisms of oxidative stress in the potentiation of noise -induced hearing loss by acrylonitrile. (cdc.gov)
Attenuates oxidative stress2
- With this in mind, the present study investigates whether maltol attenuates oxidative stress injury in primary RGCs in vitro. (molvis.org)
- Alamandine attenuates oxidative stress in the right carotid following transverse aortic constriction in mice. (bvsalud.org)
Damage26
- Oxidative stress from oxidative metabolism causes base damage, as well as strand breaks in DNA. (wikipedia.org)
- DNA damage induced by ionizing radiation is similar to oxidative stress, and these lesions have been implicated in aging and cancer. (wikipedia.org)
- Ovulation-induced oxidative base damage and damage to DNA of the ovarian epithelium can be prevented by antioxidants. (nih.gov)
- The patho-physiological characteristic of AD is abnormal deposition of fibrillar amyloid β protein, intracellular neurofibrillary tangles, oxidative damage and neuronal death in the brain. (springer.com)
- Increased free radical activity ( oxidative stress ) appears to fuel Alzheimer's pathology - acting simultaneously as a mediator, product, and trigger for this "clogging" process and its related neural damage. (diagnose-me.com)
- Activation of this receptor leads to increased oxidative stress that may result in cellular damage. (diagnose-me.com)
- The influx and subsequent activation of such inflammatory cells into the lung therefore may lead to an oxidative burst which overwhelms the pulmonary antioxidative defences, resulting in oxidative DNA damage. (ecetoc.org)
- That's where it's most important - where the cascade effect of oxidative damage begins. (limoneira.com)
- The in vitro test exposed the lemon peel extract to a specific type of rat heart cell with oxidative damage. (limoneira.com)
- LPE has the potential to be developed into natural medicine or health food for the inhibition of cell oxidative damage. (limoneira.com)
- Oxidative damage to DNA results from the interaction of DNA with ROS, in particular, hydroxy radicals. (dojindo.com)
- However, clinical data clearly indicate that oxidative DNA damage is related to a number of disease processes such as carcinogenesis and neurodegenerative diseases. (dojindo.com)
- Since glutathione also has superoxidescavenging activity, it contributes to a reductive atmosphere in cells and tissues to avoid oxidative damage. (dojindo.com)
- In addition, we found that isolated islets from Chop -/- mice displayed increased expression of UPR and oxidative stress response genes and reduced levels of oxidative damage. (jci.org)
- The most significant extrinsic factor causing accelerated skin aging is exposure to UV light leading to the production of ROS (Stojiljkovic, 2014) which cause oxidative damage. (promocell.com)
- However, the excessive generation of ROS, such as super oxide anions (O 2 − ) and hydrogen peroxide (H 2 O 2 ) due to environmental stress results in significant oxidative damage to cell structures, such as DNA, the mitochondria and cell membranes ( 3 , 4 ). (spandidos-publications.com)
- The activation of the antioxidant system is insufficient to combat oxidative stress damage. (ajol.info)
- In the presence of hydrogen peroxide, myeloperoxidase can exhibit two activities: chlorination and peroxidation, both of which can result in oxidative damage. (huntingtree.co.nz)
- Our OxiSelect™ Oxidized HDL ELISA Kits provide a fast, convenient way to measure the oxidative damage to HDL in plasma or serum samples. (huntingtree.co.nz)
- Oxidative damage and tyrosine nitration from peroxynitrite. (scienceopen.com)
- If these DNA-parts have been affected by oxidative damage, however, they cannot be properly detected for epigenetic highlights any more. (my-fertility-blog.com)
- In the 12-week study , the researchers concluded that Zeropollution reduced oxidative stress-induced skin damage and that the oral intake of this supplement may be considered a complementary nutrition strategy to avoid the negative effects of environmental pollution exposure. (nutritioninsight.com)
- Oxidative damage on the skin (lipoperoxides content). (nutritioninsight.com)
- Abundant evidence indicates that free radical mediated oxidative damage in the brain is prominent in AD, especially in the earliest detectable clinical phase of AD - mild cognitive impairment (MCI). (uky.edu)
- Project 4 examines the hypothesis that sustained activation of NADPH oxidase by toxic forms of Aj3 triggers a cascade linking increased ROS to altered redox-based signaling and neurotoxic oxidative damage. (uky.edu)
- The mechanism by which ACN renders the cochlea more vulnerable to noise damage is still unknown, but we hypothesize that the decrease of GSH and/or the inhibition of SOD reduce the cochlear intrinsic anti-oxidant defenses and ultimately create oxidative stress. (cdc.gov)
Metabolism4
- SOD is a potential therapeutic agent in diseases related to oxidative stress and as a material for moderating the aging process, because of its high antioxidant efficiency (much higher than that of glutathione or other reducing agents) and early action in the initial stages of ROS metabolism. (dojindo.com)
- The objective of this study was to determine the combined effect of graded levels of -tocopherol with different levels and sources of krill phospholipids (KPL) and soybean lecithin (SBL) on growth, survival, resistance to stress, oxidative status, bone metabolism-related genes expression and biochemical composition of sea bream larvae. (stir.ac.uk)
- Amino acids also contribute to cellular energy metabolism by providing a carbon source for entry into the citric acid cycle (tricarboxylic acid cycle), especially when a primary source of energy, such as glucose, is scarce, or when cells undergo metabolic stress. (wikipedia.org)
- For this purpose, two different drugs were used: (1) Sodium thiosulfate (STS), a CN antidote commonly used in humans in case of CN poisoning and (2) 4-methylpyrazole (4MP) which blocks ACN metabolism through the oxidative pathway, preventing CN formation. (cdc.gov)
Neurons1
- Neurons are most susceptible to direct oxidative injury by ROS and RNS. (unboundmedicine.com)
Important roles in the pathogenesis2
- Oxidative stress and neuroinflammation play important roles in the pathogenesis of AD. (nature.com)
- Oxidative and nitrosative stress plays important roles in the pathogenesis of renal ischemia/reperfusion (I/R) injury. (scienceopen.com)
Pathogenesis4
- Our study identified 9 key genes associated with oxidative stress and immune reaction in AD pathogenesis. (nature.com)
- There is data that indicates that the brain in AD is under increased oxidative stress, which may have a role in the pathogenesis of neuron degeneration and death in this disorder. (anavex.com)
- Nerve terminals may play a role in early pathogenesis and presymptomatic disease - but oxidative changes also occur as a result of the normal aging process, and are not specific to AD, he cautioned. (anavex.com)
- Oxidative stress takes part in the pathogenesis of inflammatory bowel disease (IBD). (ecco-ibd.eu)
Indicate that oxidative1
- These data indicate that oxidative potential via oxidative stress can potentially increase tenderization early postmortem, which may provide more tender meat with no detriment to other meat quality factors. (unl.edu)
Produce oxidative1
- They were looking specifically for downstream changes in gene expression that would produce oxidative stress in the cell, a circumstance in which highly reactive forms of oxygen can create a toxic environment. (sciencedaily.com)
Alzheimer's1
- Medivation's (NASDAQ:MDVN) Dimebon for the treatment of Alzheimer's disease (AD) may have some effect on the oxidative stress pathway, an investigator and physicians said. (anavex.com)
Pathway2
- In contrast, expression of an active dephosphorylation-resistant PKD1 mutant potentiates the IKK/NF-κB/SOD2 oxidative stress detoxification pathway and confers neuroprotection from in vitro and in vivo excitotoxicity. (nature.com)
- Obviously targeting mitochondria makes sense therapeutically, if you want to target the oxidative stress pathway. (anavex.com)
Toxicity2
- The question as to what causes the destruction of the dopamine-producing cells has puzzled researchers for years but a consensus is now emerging that Parkinson's disease is caused by oxidative stress and metal toxicity. (diagnose-me.com)
- In this study, we report that both nano- and micro-CoCrMo induced a time and dose-dependent toxicity in various cell types (i.e. lung epithelial cells, osteoblasts, and macrophages), and the effects of particle size on cell viability and oxidative responses were interesting and cell specific. (whiterose.ac.uk)
Antioxidants3
- Since this mutagenic response was inhibited in the presence of catalase as antioxidant, the authors concluded that oxidative stress in form of the generation and release of ROS and/or depletion of antioxidants may significantly contribute to this response. (ecetoc.org)
- Recent studies have demonstrated that antioxidants present in natural products protect cells by reducing H 2 O 2 -induced oxidative stress in vitro and in vivo ( 5 - 7 ). (spandidos-publications.com)
- In addition to sticking to healthy choices well before conception , it is vital to protect vulnerable sperms and oocytes from increased oxidative stress and supply the body with ample antioxidants . (my-fertility-blog.com)
Vivo4
- Oxidative stress is an important activator of PKD1 in cellular models, but its capacity to activate this kinase in vivo is largely unknown. (nature.com)
- 4-Hydroxy-2-nonenal (HNE), among them, is believed to be largely responsible for cytopathological effects observed during oxidative stree in vivo and has achieved the status of one of the best recognized and most studied of the cytotoxic products of lipid peroxidation. (nih.gov)
- Previous in vitro and in vivo studies revealed that oxidative stress caused by the accumulation of Aβ contributed to the initiation of AD 8 . (nature.com)
- However, EUK-134 also reduced nitrosative stress caused by I/R in vivo (reduction of iNOS expression and nitrotyrosine formation), which was reflected by a significant reduction in serum NO levels in rats subjected to renal I/R. Specifically, serum NO levels were reduced from 57 ± 12 (n = 12, I/R only) to 23 ± 3 m M (n = 12, I/R +3 mg/kg EUK-134). (scienceopen.com)
Neuroprotection1
- Dr Samantha Budd, director of neurology strategy at AstraZeneca (NYSE:AZN), said AstraZeneca has a broad effort in AD, but does not have approaches on oxidative stress or neuroprotection. (anavex.com)
Hypothesis3
- Dr Mark Smith, an investigator on Dimebon's trials who has studied the oxidative stress hypothesis for more than 15 years at Case Western Reserve University, said the clinical data on Dimebon looks very promising, especially if it is hitting mitochondria. (anavex.com)
- Our hypothesis is that those spermatogonia experiencing high oxidative stress by any stressor, differentiate into spermatozoa of low quality affecting male fertility. (ualg.pt)
- GERMROS project will explore the first part of this hypothesis, testing the resilience of spermatogonia to oxidative stress in a marine flatfish species, the Senegalese sole (Solea senegalensis), which is a promising candidate for aquaculture production in Europe but presents reproductive disorders, making this species ideal for the study proposed. (ualg.pt)
Oxidation1
- This study was conducted to evaluate the relationship between animal oxidative status, using lipopolysaccharide (LPS) as a promoter for oxidation. (unl.edu)
Cellular4
- Further, some reactive oxidative species act as cellular messengers in redox signaling. (wikipedia.org)
- Of note, DAPK can activate PKD in HeLa cells under oxidative stress conditions 11 , thus suggesting that PKD activation may contribute to cellular death. (nature.com)
- Results show lambs administered lipopolysaccharide treatments exhibited greater oxidative potential, as indicated by increased rectal temperatures, and upregulated expression of mRNA protein pathways essential for cellular differentiation, proliferation, and apoptotic events. (unl.edu)
- G promoter SNP and potentially cellular oxidative stress. (diabetesjournals.org)
Neurodegenerative Diseases1
- The purpose of this review is to summarize the current evidence in support of this critical role played by oxidative stress of neuronal and glial origin in neurodegenerative diseases. (unboundmedicine.com)
Diseases5
- As such, they concluded that the aqueous extract could be used as a local or systemic preventive agent against oral diseases caused by oxidative stress in diabetic subjects. (naturalnews.com)
- Maltol has potential as a new neuroprotective therapeutic agent for oxidative stress-related ocular diseases, including glaucoma. (molvis.org)
- The age-related alteration of collagen-rich extracellular matrix - promoted by oxidative stress - impairs the skin's structural integrity and creates a tissue microenvironment that promotes age-related skin diseases such as poor wound healing and skin cancer. (promocell.com)
- Our findings highlight the potential roles that nano- and micro-CoCrMo, whether exposure is due to inhalation or implant wear, and the associated oxidative stress may play in the increasingly reported implant loosening, osteolysis, and systemic complications in orthopaedic patients, and may explain the risk of lung diseases in dental workers. (whiterose.ac.uk)
- Department of Oxidative Stress and Human Diseases, MIGAL - Galilee Research Institute and Tel Hai College, Kiryat Shmona. (who.int)
Glutathione1
- Chemically, oxidative stress is associated with increased production of oxidizing species or a significant decrease in the effectiveness of antioxidant defenses, such as glutathione. (wikipedia.org)
H2O21
- The high H2O2 tolerance of aerobic S. aureus cells was associated with priming by endogenous H2O2 levels, which was supported by an oxidative shift of the bacillithiol redox potential to −291 mV compared to −310 mV in microaerophilic cells. (fu-berlin.de)
Nitrosative2
- The expression of poly(ADP-ribose) (PAR) and inducible nitric oxide (NO) synthase (iNOS) and nitrotyrosine formation were determined immunohistochemically and used as indicators of oxidative and nitrosative stress. (scienceopen.com)
- We propose that EUK-134 reduces renal I/R injury not only via reduction of oxidative stress, but also by reducing nitrosative stress caused by renal I/R. (scienceopen.com)
Lipid3
- There is increasing evidence that aldehydic molecules generated endogenously during the process of lipid peroidation are causally involved in most of the pathophysiological effects associated with oxidative stress in cells and tissues. (nih.gov)
- It is accompanied by dyslipidemia and oxidative stress leading to increase in lipid peroxidation . (bvsalud.org)
- This study demonstrated an increased occurrence of atherogenic lipid profile and oxidative stress among hypertensive patients . (bvsalud.org)
Stressor2
- But researchers from Argentina's Universidad de Buenos Aires and the Instituto de Investigaciones Biomédicas UCA-CONICET noted that the effect of the L. divaricata aqueous extract on the homeostasis in submandibular glands subjected to the effects of an oxidative stressor has not yet been studied. (naturalnews.com)
- One of these was a control group and the other was injected with 60 milligrams per kilogram of streptozoticin (STZ), a known oxidative stressor. (naturalnews.com)
Isoprostanes1
- Isoprostanes are excellent molecular biomarkers for oxidant stress. (oxfordbiomed.com)
Skin's1
- A new ingredient in some skin care products, beta-glucan, increases the skin's resistance to oxidative stress induced by UVA rays. (diagnose-me.com)
Cytokines1
- Complex interplay between cytokines and oxidative stress in the etiology of female reproductive disorders is discussed. (nih.gov)
Redox2
- Oxidative stress is involved in the modulation of gene expression patterns and metabolic activities, characterized by the disruption of redox homeostasis 7 . (nature.com)
- The intracellular redox reaction between carbon black and Fe3+ is likely responsible for the synergistic oxidative effect. (rti.org)
Activates1
- Since oxidative stress activates protein kinase D1 (PKD1) in tumor cells, we investigated the effect of excitotoxicity on neuronal PKD1 activity. (nature.com)
Clinical5
- There is a lot of literature on oxidative pathways, but very little clinical data, Budd said. (anavex.com)
- But it would be interesting to see if there is clinical success that could be coupled to oxidative stress in AD," she noted. (anavex.com)
- Oxidative biomarkers were correlated with clinical parameters. (ecco-ibd.eu)
- It is therefore important to estimate and prevent the risks encountered by astronauts due to oxidative stress prior to developing clinical symptoms of disease. (drsircus.com)
- 10 May 2021 --- Monteloeder's proprietary, polyphenol-rich dietary ingredient, Zeropollution, may improve the signs of skin aging, strengthen skin barrier function and counteract oxidative stress, according to a new clinical study. (nutritioninsight.com)
Study8
- With that in mind, a group of researchers conducted a study on whether an aqueous extract can be used to treat oxidative stress in the submandibular glands of diabetic rats. (naturalnews.com)
- A 2021 study by Chinese researchers added to the weight of evidence that lemon peel, rich in many bioactive compounds, can inhibit oxidative stress at the level of the cell. (limoneira.com)
- Cell assays and primary cells provide the tools researchers need to study the oxidative process and its association with skin aging. (promocell.com)
- The findings of the present study indicated that inhibition of miR‑132 may ameliorate myocardial I/R injury by inhibiting oxidative stress and pyroptosis through activation of PGC‑1α/Nrf2 signalling by targeting SIRT1. (spandidos-publications.com)
- The aim of this study was to explore the oxidative stress mechanism of cotton smoke inhalation-induced pulmonary injury in a rat model. (ajol.info)
- Besides, the study suggests that B 2 or B 6 vitamins restored the levels of DA and reduced oxidative stress in brain of rats. (biomedcentral.com)
- The study was designed to assess the efficacy of oral supplementation with Zeropollution in reducing pollution-induced oxidative stress and in improving a variety of skin parameters related to skin aging. (nutritioninsight.com)
- Thus, in this study, we aimed to assess the effects of alamandine treatment on right carotid remodeling and the expression of oxidative stress -related substances induced by TAC. (bvsalud.org)
Expression2
- Other effects of increased oxidative stress and ROS production are a decrease in CTGF, TGF-beta, and type I procollagen expression as well as an age-associated chronic progressive increase in the proinflammatory status - this is termed 'inflammaging' (Zuo, 2019). (promocell.com)
- Indeed, dietary -tocopherol decreased the oxidative stress in the larvae as denoted by the reduction in larval TBARs contents and gene expression of SOD and CAT, but not GPX. (stir.ac.uk)
Exposure2
- During particle exposure, ROS and RNS are mainly generated from the oxidative burst of pulmonary inflammatory cells, i.e. neutrophils and AMs. (ecetoc.org)
- Co-exposure to carbon black and Fe2O3 particles causes a synergistic oxidative effect that is significantly greater than the additive effects of exposures to either particle type alone. (rti.org)
Cells6
- Atherosclerosis starts with dysfunctional changes in the endothelium induced by disturbed shear stress which can lead to endothelial and platelet activation, adhesion of monocytes on the activated endothelium, and differentiation into proinflammatory macrophages, which increase the uptake of oxidized LDL (oxLDL) and turn into foam cells, exacerbating the inflammatory signalling. (hindawi.com)
- To evaluate the neuroprotective and neurite outgrowth effects of maltol, a natural aroma compound, on retinal ganglion cells (RGCs) under oxidative stress in vitro. (molvis.org)
- This oxidative stress significantly increased the number of TUNEL-positive RGCs, but the maltol drastically reduced the proportion of those apoptotic cells. (molvis.org)
- However, after it was discovered that oxidative stress injury to retinal ganglion cells (RGCs) is a leading pathophysiology of glaucoma [ 2 ], researchers' attention has turned to how to directly rescue the damaged RGCs from fatal oxidative stress. (molvis.org)
- The method was used to measure the native presence of carnosine in these cells, as well as investigate its uptake under normal and pro-oxidative conditions. (ku.edu)
- It has been observed that the effect of oxidative stress is tissue and cell-dependant, where some specific cells are more tolerant to ROS than others. (ualg.pt)
Largely2
- Repair of oxidative damages to DNA is frequent and ongoing, largely keeping up with newly induced damages. (wikipedia.org)
- So far a putative role for sucrose and SOS during oxidative stress has largely been neglected, as has the contribution of the vacuolar compartment. (lincoln.ac.uk)