A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.
Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.
An enzyme that catalyzes reversibly the conversion of palmitoyl-CoA to palmitoylcarnitine in the inner mitochondrial membrane. EC 2.3.1.21.
An enzyme that catalyzes the formation of O-acetylcarnitine from acetyl-CoA plus carnitine. EC 2.3.1.7.
Acyltransferases in the inner mitochondrial membrane that catalyze the reversible transfer of acyl groups from acyl-CoA to L-carnitine and thereby mediate the transport of activated fatty acids through that membrane. EC 2.3.1.
An enzyme that transfers acyl groups from acyl-CoA to glycerol-3-phosphate to form monoglyceride phosphates. It acts only with CoA derivatives of fatty acids of chain length above C-10. Also forms diglyceride phosphates. EC 2.3.1.15.
An enzyme secreted from the liver into the plasma of many mammalian species. It catalyzes the esterification of the hydroxyl group of lipoprotein cholesterol by the transfer of a fatty acid from the C-2 position of lecithin. In familial lecithin:cholesterol acyltransferase deficiency disease, the absence of the enzyme results in an excess of unesterified cholesterol in plasma. EC 2.3.1.43.
An enzyme that catalyses the last step of the TRIACYLGLYCEROL synthesis reaction in which diacylglycerol is covalently joined to LONG-CHAIN ACYL COA to form triglyceride. It was formerly categorized as EC 2.3.1.124.
An enzyme that catalyzes the formation of cholesterol esters by the direct transfer of the fatty acid group from a fatty acyl CoA derivative. This enzyme has been found in the adrenal gland, gonads, liver, intestinal mucosa, and aorta of many mammalian species. EC 2.3.1.26.
An autosomal recessively inherited disorder caused by mutation of LECITHIN CHOLESTEROL ACYLTRANSFERASE that facilitates the esterification of lipoprotein cholesterol and subsequent removal from peripheral tissues to the liver. This defect results in low HDL-cholesterol level in blood and accumulation of free cholesterol in tissue leading to a triad of CORNEAL OPACITY, hemolytic anemia (ANEMIA, HEMOLYTIC), and PROTEINURIA.
An enzyme localized predominantly within the plasma membrane of lymphocytes. It catalyzes the transfer of long-chain fatty acids, preferentially unsaturated fatty acids, to lysophosphatides with the formation of 1,2-diacylglycero-3-phosphocholine and CoA. EC 2.3.1.23.
S-Acyl coenzyme A. Fatty acid coenzyme A derivatives that are involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.
An acetic acid ester of CARNITINE that facilitates movement of ACETYL COA into the matrices of mammalian MITOCHONDRIA during the oxidation of FATTY ACIDS.
A fatty acid coenzyme derivative which plays a key role in fatty acid oxidation and biosynthesis.
A coenzyme A derivative which plays a key role in the fatty acid synthesis in the cytoplasmic and microsomal systems.
An enzyme that catalyzes the HYDROXYLATION of gamma-butyrobetaine to L-CARNITINE. It is the last enzyme in the biosynthetic pathway of L-CARNITINE and is dependent on alpha-ketoglutarate; IRON; ASCORBIC ACID; and OXYGEN.
An enzyme that catalyzes the acyl group transfer of ACYL COA to 1-acyl-sn-glycerol 3-phosphate to generate 1,2-diacyl-sn-glycerol 3-phosphate. This enzyme has alpha, beta, gamma, delta and epsilon subunits.
A family of proteins involved in the transport of organic cations. They play an important role in the elimination of a variety of endogenous substances, xenobiotics, and their metabolites from the body.
The process of converting an acid into an alkyl or aryl derivative. Most frequently the process consists of the reaction of an acid with an alcohol in the presence of a trace of mineral acid as catalyst or the reaction of an acyl chloride with an alcohol. Esterification can also be accomplished by enzymatic processes.
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
A long-chain fatty acid ester of carnitine which facilitates the transfer of long-chain fatty acids from cytoplasm into mitochondria during the oxidation of fatty acids.
The addition of an organic acid radical into a molecule.
Coenzyme A is an essential coenzyme that plays a crucial role in various metabolic processes, particularly in the transfer and activation of acetyl groups in important biochemical reactions such as fatty acid synthesis and oxidation, and the citric acid cycle.
Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Triglycerides are the most common type of fat in the body, stored in fat cells and used as energy; they are measured in blood tests to assess heart disease risk, with high levels often resulting from dietary habits, obesity, physical inactivity, smoking, and alcohol consumption.
Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
Any salt or ester of glycerophosphoric acid.
The most abundant protein component of HIGH DENSITY LIPOPROTEINS or HDL. This protein serves as an acceptor for CHOLESTEROL released from cells thus promoting efflux of cholesterol to HDL then to the LIVER for excretion from the body (reverse cholesterol transport). It also acts as a cofactor for LECITHIN CHOLESTEROL ACYLTRANSFERASE that forms CHOLESTEROL ESTERS on the HDL particles. Mutations of this gene APOA1 cause HDL deficiency, such as in FAMILIAL ALPHA LIPOPROTEIN DEFICIENCY DISEASE and in some patients with TANGIER DISEASE.
A naturally occurring compound that has been of interest for its role in osmoregulation. As a drug, betaine hydrochloride has been used as a source of hydrochloric acid in the treatment of hypochlorhydria. Betaine has also been used in the treatment of liver disorders, for hyperkalemia, for homocystinuria, and for gastrointestinal disturbances. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1341)
The rate dynamics in chemical or physical systems.
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
An enzyme that catalyzes the acyl group transfer of acyl COENZYME A to RETINOL to generate COENZYME A and a retinyl ester.
Pentanoic acid, also known as valeric acid, is a carboxylic acid with a 5-carbon chain (C5H10O2), having a distinctive pungent and rancid odor, found in some animals' sweat, certain foods, and produced through wood fermentation.
"Esters are organic compounds that result from the reaction between an alcohol and a carboxylic acid, playing significant roles in various biological processes and often used in pharmaceutical synthesis."
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
A group of 16-carbon fatty acids that contain no double bonds.
Organic compounds that contain silicon as an integral part of the molecule.
A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.
An important intermediate in lipid biosynthesis and in glycolysis.
A mitosporic fungal species used in the production of penicillin.
Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
Errors in the metabolism of LIPIDS resulting from inborn genetic MUTATIONS that are heritable.
A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Organic compounds that include a cyclic ether with three ring atoms in their structure. They are commonly used as precursors for POLYMERS such as EPOXY RESINS.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Derivatives of PHOSPHATIDYLCHOLINES obtained by their partial hydrolysis which removes one of the fatty acid moieties.
The metabolic substances ACETONE; 3-HYDROXYBUTYRIC ACID; and acetoacetic acid (ACETOACETATES). They are produced in the liver and kidney during FATTY ACIDS oxidation and used as a source of energy by the heart, muscle and brain.
Derivatives of caprylic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated eight carbon aliphatic structure.
Salts and esters of the 16-carbon saturated monocarboxylic acid--palmitic acid.
A condition due to deficiency in any member of the VITAMIN B COMPLEX. These B vitamins are water-soluble and must be obtained from the diet because they are easily lost in the urine. Unlike the lipid-soluble vitamins, they cannot be stored in the body fat.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Lengthy and continuous deprivation of food. (Stedman, 25th ed)
An unsaturated fatty acid that is the most widely distributed and abundant fatty acid in nature. It is used commercially in the preparation of oleates and lotions, and as a pharmaceutical solvent. (Stedman, 26th ed)
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
A standard reagent for the determination of reactive sulfhydryl groups by absorbance measurements. It is used primarily for the determination of sulfhydryl and disulfide groups in proteins. The color produced is due to the formation of a thio anion, 3-carboxyl-4-nitrothiophenolate.
A plastic substance deposited by insects or obtained from plants. Waxes are esters of various fatty acids with higher, usually monohydric alcohols. The wax of pharmacy is principally yellow wax (beeswax), the material of which honeycomb is made. It consists chiefly of cerotic acid and myricin and is used in making ointments, cerates, etc. (Dorland, 27th ed)
Enzymes that catalyze the formation of acyl-CoA derivatives. EC 6.2.1.
Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.
Conditions with abnormally low levels of LIPOPROTEINS in the blood. This may involve any of the lipoprotein subclasses, including ALPHA-LIPOPROTEINS (high-density lipoproteins); BETA-LIPOPROTEINS (low-density lipoproteins); and PREBETA-LIPOPROTEINS (very-low-density lipoproteins).
An enzyme that catalyzes the hydrolysis of a single fatty acid ester bond in lysoglycerophosphatidates with the formation of glyceryl phosphatidates and a fatty acid. EC 3.1.1.5.
Disorder occurring in the central or peripheral area of the cornea. The usual degree of transparency becomes relatively opaque.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
A common saturated fatty acid found in fats and waxes including olive oil, palm oil, and body lipids.
A fibric acid derivative used in the treatment of HYPERLIPOPROTEINEMIA TYPE III and severe HYPERTRIGLYCERIDEMIA. (From Martindale, The Extra Pharmacopoeia, 30th ed, p986)
Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.
GLYCEROL esterified with a single acyl (FATTY ACIDS) chain.
Structural proteins of the alpha-lipoproteins (HIGH DENSITY LIPOPROTEINS), including APOLIPOPROTEIN A-I and APOLIPOPROTEIN A-II. They can modulate the activity of LECITHIN CHOLESTEROL ACYLTRANSFERASE. These apolipoproteins are low in atherosclerotic patients. They are either absent or present in extremely low plasma concentration in TANGIER DISEASE.
Diglycerides are a type of glyceride, specifically a form of lipid, that contains two fatty acid chains linked to a glycerol molecule by ester bonds.
A naturally occurring metabolite of HISTIDINE that has antioxidant properties.
Covalent attachment of LIPIDS and FATTY ACIDS to other compounds and PROTEINS.
Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent.
BUTYRIC ACID substituted in the beta or 3 position. It is one of the ketone bodies produced in the liver.
Enzyme catalyzing reversibly the hydrolysis of palmitoyl-CoA or other long-chain acyl coenzyme A compounds to yield CoA and palmitate or other acyl esters. The enzyme is involved in the esterification of fatty acids to form triglycerides. EC 3.1.2.2.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
Enzymes catalyzing the transfer of an acetyl group, usually from acetyl coenzyme A, to another compound. EC 2.3.1.
Transport proteins that carry specific substances in the blood or across cell membranes.
A form of encephalopathy with fatty infiltration of the LIVER, characterized by brain EDEMA and VOMITING that may rapidly progress to SEIZURES; COMA; and DEATH. It is caused by a generalized loss of mitochondrial function leading to disturbances in fatty acid and CARNITINE metabolism.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis.
Retinol and derivatives of retinol that play an essential role in metabolic functioning of the retina, the growth of and differentiation of epithelial tissue, the growth of bone, reproduction, and the immune response. Dietary vitamin A is derived from a variety of CAROTENOIDS found in plants. It is enriched in the liver, egg yolks, and the fat component of dairy products.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.
Derivatives of PHOSPHATIDIC ACIDS that lack one of its fatty acyl chains due to its hydrolytic removal.
Consists of a polypeptide chain and 4'-phosphopantetheine linked to a serine residue by a phosphodiester bond. Acyl groups are bound as thiol esters to the pantothenyl group. Acyl carrier protein is involved in every step of fatty acid synthesis by the cytoplasmic system.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
Fatty acid derivatives of glycerophosphates. They are composed of glycerol bound in ester linkage with 1 mole of phosphoric acid at the terminal 3-hydroxyl group and with 2 moles of fatty acids at the other two hydroxyl groups.
FATTY ACIDS found in the plasma that are complexed with SERUM ALBUMIN for transport. These fatty acids are not in glycerol ester form.
A sulfhydryl reagent that is widely used in experimental biochemical studies.
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
Proteins prepared by recombinant DNA technology.
Large enzyme complexes composed of a number of component enzymes that are found in STREPTOMYCES which biosynthesize MACROLIDES and other polyketides.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
An abnormal lipoprotein present in large amounts in patients with obstructive liver diseases such as INTRAHEPATIC CHOLESTASIS. LP-X derives from the reflux of BILE lipoproteins into the bloodstream. LP-X is a low-density lipoprotein rich in free CHOLESTEROL and PHOSPHOLIPIDS but poor in TRIGLYCERIDES; CHOLESTEROL ESTERS; and protein.
A phosphomonoesterase involved in the synthesis of triacylglycerols. It catalyzes the hydrolysis of phosphatidates with the formation of diacylglycerols and orthophosphate. EC 3.1.3.4.
Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)
An enzyme that catalyzes the hydrolysis of CHOLESTEROL ESTERS and some other sterol esters, to liberate cholesterol plus a fatty acid anion.
The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.
Enzymes that catalyze the reversible reduction of alpha-carboxyl group of 3-hydroxy-3-methylglutaryl-coenzyme A to yield MEVALONIC ACID.
Elevated level of AMMONIA in the blood. It is a sign of defective CATABOLISM of AMINO ACIDS or ammonia to UREA.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. (From Dorland, 27th ed) EC 3.1.1.3.
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
Lipid A is the biologically active component of lipopolysaccharides. It shows strong endotoxic activity and exhibits immunogenic properties.
A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.
A mitosporic Trichocomaceae fungal genus that develops fruiting organs resembling a broom. When identified, teleomorphs include EUPENICILLIUM and TALAROMYCES. Several species (but especially PENICILLIUM CHRYSOGENUM) are sources of the antibiotic penicillin.
The second most abundant protein component of HIGH DENSITY LIPOPROTEINS or HDL. It has a high lipid affinity and is known to displace APOLIPOPROTEIN A-I from HDL particles and generates a stable HDL complex. ApoA-II can modulate the activation of LECITHIN CHOLESTEROL ACYLTRANSFERASE in the presence of APOLIPOPROTEIN A-I, thus affecting HDL metabolism.
An antilipemic agent that is the biologically active metabolite of CLOFIBRATE.
Hydrazines substituted by one or more methyl groups in any position.
A class of enzymes that catalyze the hydrolysis of phosphoglycerides or glycerophosphatidates. EC 3.1.-.
Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.
A toxic thiol mercury salt formerly used as a diuretic. It inhibits various biochemical functions, especially in mitochondria, and is used to study those functions.
GLYCEROL esterified with FATTY ACIDS.
Acidic phospholipids composed of two molecules of phosphatidic acid covalently linked to a molecule of glycerol. They occur primarily in mitochondrial inner membranes and in bacterial plasma membranes. They are the main antigenic components of the Wassermann-type antigen that is used in nontreponemal SYPHILIS SERODIAGNOSIS.
Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.
Proteins that bind to and transfer CHOLESTEROL ESTERS between LIPOPROTEINS such as LOW-DENSITY LIPOPROTEINS and HIGH-DENSITY LIPOPROTEINS.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
A plant species of the family FABACEAE that yields edible seeds, the familiar peanuts, which contain protein, oil and lectins.
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Six-carbon alicyclic hydrocarbons.
An enzyme that catalyzes the formation of acetoacetyl-CoA from two molecules of ACETYL COA. Some enzymes called thiolase or thiolase-I have referred to this activity or to the activity of ACETYL-COA C-ACYLTRANSFERASE.
Salts and esters of hydroxybutyric acid.
Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.
Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Contractile tissue that produces movement in animals.
Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.
GLYCEROPHOSPHOLIPIDS in which one of the two acyl chains is attached to glycerol with an ether alkenyl linkage instead of an ester as with the other glycerophospholipids.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Tritium is an isotope of hydrogen (specifically, hydrogen-3) that contains one proton and two neutrons in its nucleus, making it radioactive with a half-life of about 12.3 years, and is used in various applications including nuclear research, illumination, and dating techniques due to its low energy beta decay.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Cholesterol present in food, especially in animal products.
A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.
A genus of zygomycetous fungi of the family Mortierellaceae, order MUCORALES. Its species are abundant in soil and can cause rare infections in humans and animals. Mortierella alpinais is used for production of arachidonic acid.
Regular course of eating and drinking adopted by a person or animal.
Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987)
An autosomal recessive form of CHONDRODYSPLASIA PUNCTATA characterized by defective plasmalogen biosynthesis and impaired peroxisomes. Patients have shortened proximal limbs and severely disturbed endochondral bone formation. The metabolic defects associated with the impaired peroxisomes are present only in the rhizomelic form of chondrodysplasia punctata. (From Scriver et al, Metabolic Basis of Inherited Disease, 6th ed, p1497)
A flavoprotein oxidoreductase that has specificity for medium-chain fatty acids. It forms a complex with ELECTRON TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.
A bile acid formed by bacterial action from cholate. It is usually conjugated with glycine or taurine. Deoxycholic acid acts as a detergent to solubilize fats for intestinal absorption, is reabsorbed itself, and is used as a choleretic and detergent.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

Carnitine is a naturally occurring substance in the body that plays a crucial role in energy production. It transports long-chain fatty acids into the mitochondria, where they can be broken down to produce energy. Carnitine is also available as a dietary supplement and is often used to treat or prevent carnitine deficiency.

The medical definition of Carnitine is:

"A quaternary ammonium compound that occurs naturally in animal tissues, especially in muscle, heart, brain, and liver. It is essential for the transport of long-chain fatty acids into the mitochondria, where they can be oxidized to produce energy. Carnitine also functions as an antioxidant and has been studied as a potential treatment for various conditions, including heart disease, diabetes, and kidney disease."

Carnitine is also known as L-carnitine or levocarnitine. It can be found in foods such as red meat, dairy products, fish, poultry, and tempeh. In the body, carnitine is synthesized from the amino acids lysine and methionine with the help of vitamin C and iron. Some people may have a deficiency in carnitine due to genetic factors, malnutrition, or certain medical conditions, such as kidney disease or liver disease. In these cases, supplementation may be necessary to prevent or treat symptoms of carnitine deficiency.

Acyltransferases are a group of enzymes that catalyze the transfer of an acyl group (a functional group consisting of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydrogen atom) from one molecule to another. This transfer involves the formation of an ester bond between the acyl group donor and the acyl group acceptor.

Acyltransferases play important roles in various biological processes, including the biosynthesis of lipids, fatty acids, and other metabolites. They are also involved in the detoxification of xenobiotics (foreign substances) by catalyzing the addition of an acyl group to these compounds, making them more water-soluble and easier to excrete from the body.

Examples of acyltransferases include serine palmitoyltransferase, which is involved in the biosynthesis of sphingolipids, and cholesteryl ester transfer protein (CETP), which facilitates the transfer of cholesteryl esters between lipoproteins.

Acyltransferases are classified based on the type of acyl group they transfer and the nature of the acyl group donor and acceptor molecules. They can be further categorized into subclasses based on their sequence similarities, three-dimensional structures, and evolutionary relationships.

Carnitine O-palmitoyltransferase (CPT) is an enzyme that plays a crucial role in the transport of long-chain fatty acids into the mitochondrial matrix, where they undergo beta-oxidation to produce energy. There are two main forms of this enzyme: CPT1 and CPT2.

CPT1 is located on the outer mitochondrial membrane and catalyzes the transfer of a long-chain fatty acyl group from coenzyme A (CoA) to carnitine, forming acylcarnitine. This reaction is reversible and allows for the regulation of fatty acid oxidation in response to changes in energy demand.

CPT2 is located on the inner mitochondrial membrane and catalyzes the reverse reaction, transferring the long-chain fatty acyl group from carnitine back to CoA, allowing for the entry of the fatty acid into the beta-oxidation pathway.

Deficiencies in CPT1 or CPT2 can lead to serious metabolic disorders, such as carnitine deficiency and mitochondrial myopathies, which can cause muscle weakness, cardiomyopathy, and other symptoms. Treatment may involve dietary modifications, supplementation with carnitine or medium-chain fatty acids, and in some cases, enzyme replacement therapy.

Carnitine O-acetyltransferase (COAT) is an enzyme that plays a crucial role in the transport and metabolism of fatty acids within cells. It is also known as carnitine palmitoyltransferase I (CPT I).

The primary function of COAT is to catalyze the transfer of an acetyl group from acetyl-CoA to carnitine, forming acetylcarnitine and free CoA. This reaction is essential for the entry of long-chain fatty acids into the mitochondrial matrix, where they undergo beta-oxidation to produce energy in the form of ATP.

COAT is located on the outer membrane of the mitochondria and functions as a rate-limiting enzyme in fatty acid oxidation. Its activity can be inhibited by malonyl-CoA, which is an intermediate in fatty acid synthesis. This inhibition helps regulate the balance between fatty acid oxidation and synthesis, ensuring that cells have enough energy while preventing excessive accumulation of lipids.

Deficiencies or mutations in COAT can lead to various metabolic disorders, such as carnitine palmitoyltransferase I deficiency (CPT I deficiency), which may cause symptoms like muscle weakness, hypoglycemia, and cardiomyopathy. Proper diagnosis and management of these conditions often involve dietary modifications, supplementation with carnitine, and avoidance of fasting to prevent metabolic crises.

Carnitine acyltransferases are a group of enzymes that play a crucial role in the transport and metabolism of fatty acids within cells. These enzymes are responsible for transferring acyl groups from acyl-CoAs to carnitine, forming acylcarnitines, which can then be transported across the mitochondrial membrane and into the mitochondrial matrix.

Once inside the matrix, the acyl groups can be released from carnitine and oxidized in the beta-oxidation pathway to produce energy in the form of ATP. There are three main types of carnitine acyltransferases: Carnitine palmitoyltransferase I (CPT I), located on the outer mitochondrial membrane, which activates long-chain fatty acids for transport into the mitochondria; Carnitine palmitoyltransferase II (CPT II), located on the inner mitochondrial membrane, which reconverts acylcarnitines back to acyl-CoAs for oxidation; and carnitine octanoyltransferase (CRAT), which is involved in the metabolism of medium-chain fatty acids.

Deficiencies in these enzymes can lead to various metabolic disorders, such as CPT II deficiency, which can cause muscle weakness, hypoglycemia, and cardiomyopathy. Proper regulation of carnitine acyltransferases is essential for maintaining healthy fatty acid metabolism and overall cellular function.

Glycerol-3-Phosphate O-Acyltransferase (GPAT) is an enzyme that plays a crucial role in the biosynthesis of triacylglycerols and phospholipids, which are major components of cellular membranes and energy storage molecules. The GPAT enzyme catalyzes the initial and rate-limiting step in the glycerolipid synthesis pathway, specifically the transfer of an acyl group from an acyl-CoA donor to the sn-1 position of glycerol-3-phosphate, forming lysophosphatidic acid (LPA). This reaction is essential for the production of various glycerolipids, including phosphatidic acid, diacylglycerol, and triacylglycerol. There are four isoforms of GPAT (GPAT1-4) in humans, each with distinct subcellular localizations and functions. Dysregulation of GPAT activity has been implicated in several pathological conditions, such as metabolic disorders, cardiovascular diseases, and cancers.

Phosphatidylcholine-Sterol O-Acyltransferase (PCOAT, also known as Sterol O-Acyltransferase 1 or SOAT1) is an enzyme that plays a crucial role in the regulation of cholesterol metabolism. It is located in the endoplasmic reticulum and is responsible for the transfer of acyl groups from phosphatidylcholine to cholesterol, forming cholesteryl esters. This enzymatic reaction results in the storage of excess cholesterol in lipid droplets, preventing its accumulation in the cell membrane and potentially contributing to the development of atherosclerosis if not properly regulated.

Defects or mutations in PCOAT can lead to disruptions in cholesterol homeostasis, which may contribute to various diseases such as cardiovascular disorders, metabolic syndrome, and neurodegenerative conditions. Therefore, understanding the function and regulation of this enzyme is essential for developing therapeutic strategies aimed at managing cholesterol-related disorders.

Diacylglycerol O-Acyltransferase (DGAT) is an enzyme that catalyzes the final step in triacylglycerol synthesis, which is the formation of diacylglycerol and fatty acyl-CoA into triacylglycerol. This enzyme plays a crucial role in lipid metabolism and energy storage in cells. There are two main types of DGAT enzymes, DGAT1 and DGAT2, which share limited sequence similarity but have similar functions. Inhibition of DGAT has been explored as a potential therapeutic strategy for the treatment of obesity and related metabolic disorders.

Sterol O-Acyltransferase (SOAT, also known as ACAT for Acyl-CoA:cholesterol acyltransferase) is an enzyme that plays a crucial role in cholesterol homeostasis within cells. Specifically, it catalyzes the reaction of esterifying free cholesterol with fatty acyl-coenzyme A (fatty acyl-CoA) to form cholesteryl esters. This enzymatic activity allows for the intracellular storage of excess cholesterol in lipid droplets, reducing the levels of free cholesterol in the cell and thus preventing its potential toxic effects on membranes and proteins. There are two isoforms of SOAT, SOAT1 and SOAT2, which exhibit distinct subcellular localization and functions. Dysregulation of SOAT activity has been implicated in various pathological conditions, including atherosclerosis and neurodegenerative disorders.

Lecithin:cholesterol acyltransferase (LCAT) deficiency is a genetic disorder that affects the metabolism of cholesterol in the body. LCAT is an enzyme that helps to convert cholesterol into a form that can be easily transported in the bloodstream.

In LCAT deficiency, the activity of this enzyme is reduced or absent, leading to an accumulation of cholesterol in various tissues and organs of the body. This can result in a range of symptoms, including corneal opacities (clouding of the clear outer layer of the eye), hemolytic anemia (destruction of red blood cells), proteinuria (excess protein in the urine), and kidney failure.

There are two main types of LCAT deficiency: a complete form, known as fish-eye disease, which is characterized by corneal opacities but few other symptoms; and an incomplete form, known as LCAT deficiency with systemic involvement, which can affect multiple organs and systems of the body.

LCAT deficiency is caused by mutations in the LCAT gene, which provides instructions for making the LCAT enzyme. Inheritance is autosomal recessive, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the disorder.

1-Acylglycerophosphocholine O-Acyltransferase is an enzyme that belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. It is responsible for catalyzing the reaction that transfers an acyl group from an acyl-CoA to the sn-2 position of 1-acylglycerophosphocholine, resulting in the formation of phosphatidylcholine, which is a major component of biological membranes. This enzyme plays a crucial role in lipid metabolism and has been implicated in various diseases, including atherosclerosis, non-alcoholic fatty liver disease, and cancer.

Acyl Coenzyme A (often abbreviated as Acetyl-CoA or Acyl-CoA) is a crucial molecule in metabolism, particularly in the breakdown and oxidation of fats and carbohydrates to produce energy. It is a thioester compound that consists of a fatty acid or an acetate group linked to coenzyme A through a sulfur atom.

Acyl CoA plays a central role in several metabolic pathways, including:

1. The citric acid cycle (Krebs cycle): In the mitochondria, Acyl-CoA is formed from the oxidation of fatty acids or the breakdown of certain amino acids. This Acyl-CoA then enters the citric acid cycle to produce high-energy electrons, which are used in the electron transport chain to generate ATP (adenosine triphosphate), the main energy currency of the cell.
2. Beta-oxidation: The breakdown of fatty acids occurs in the mitochondria through a process called beta-oxidation, where Acyl-CoA is sequentially broken down into smaller units, releasing acetyl-CoA, which then enters the citric acid cycle.
3. Ketogenesis: In times of low carbohydrate availability or during prolonged fasting, the liver can produce ketone bodies from acetyl-CoA to supply energy to other organs, such as the brain and heart.
4. Protein synthesis: Acyl-CoA is also involved in the modification of proteins by attaching fatty acid chains to them (a process called acetylation), which can influence protein function and stability.

In summary, Acyl Coenzyme A is a vital molecule in metabolism that connects various pathways related to energy production, fatty acid breakdown, and protein modification.

Acetyl-L-carnitine, also known as ALCAR, is a form of the amino acid carnitine. It is a naturally occurring substance in the body that plays a crucial role in energy production in cells, particularly within mitochondria, the "powerhouses" of the cell.

Acetyl-L-carnitine is involved in the transport of fatty acids into the mitochondria, where they can be broken down to produce energy. It also functions as an antioxidant, helping to protect cells from damage caused by free radicals.

This compound has been studied for its potential benefits in various medical conditions, including neurological disorders, cardiovascular diseases, and liver diseases. Some research suggests that Acetyl-L-carnitine may help improve cognitive function, reduce fatigue, and alleviate pain. However, more studies are needed to confirm these findings and establish the optimal dosage and safety profiles for different medical conditions.

It is important to note that while Acetyl-L-carnitine is available as a dietary supplement, its use should be discussed with a healthcare provider before starting any new supplement regimen, especially if you have a medical condition or are taking medication.

Palmitoyl Coenzyme A, often abbreviated as Palmitoyl-CoA, is a type of fatty acyl coenzyme A that plays a crucial role in the body's metabolism. It is formed from the esterification of palmitic acid (a saturated fatty acid) with coenzyme A.

Medical Definition: Palmitoyl Coenzyme A is a fatty acyl coenzyme A ester, where palmitic acid is linked to coenzyme A via an ester bond. It serves as an important intermediate in lipid metabolism and energy production, particularly through the process of beta-oxidation in the mitochondria. Palmitoyl CoA also plays a role in protein modification, known as S-palmitoylation, which can affect protein localization, stability, and function.

Malonyl Coenzyme A (CoA) is not a medical term per se, but rather a biochemical concept. Here's the scientific or biochemical definition:

Malonyl Coenzyme A is an important intermediate in various metabolic pathways, particularly in fatty acid synthesis. It is formed through the reaction between malonic acid and coenzyme A, catalyzed by the enzyme acetyl-CoA carboxylase. Malonyl CoA plays a crucial role in the elongation step of fatty acid synthesis, where it provides the two-carbon unit that is added to a growing fatty acid chain.

In a medical context, understanding the function and regulation of Malonyl CoA metabolism can be relevant for several pathological conditions, including metabolic disorders like diabetes and obesity.

Gamma-Butyrobetaine Dioxygenase (GBD, or also known as ETHE1) is an enzyme that catalyzes the conversion of gamma-butyrobetaine to succinate and hydrogen peroxide in the final step of L-carnitine biosynthesis. This mitochondrial matrix enzyme requires iron (Fe2+) as a cofactor for its activity. Deficiency or mutations in this enzyme can lead to a rare genetic disorder called "ethylmalonic aciduria and combined oxidative phosphorylation deficiency type 6" (ETHE1), which is characterized by the accumulation of ethylmalonic acid, gamma-butyrobetaine, and other organic acids in body fluids.

1-Acylglycerol-3-Phosphate O-Acyltransferase is an enzyme that catalyzes the reaction of forming diacylglycerol phosphate (also known as phosphatidic acid) from 1-acylglycerol-3-phosphate and acyl-CoA. This enzyme plays a crucial role in the biosynthesis of glycerophospholipids, which are major components of biological membranes. The systematic name for this enzyme is 1-acylglycerol-3-phosphate O-acyltransferase; alternatively, it may also be referred to as lysophosphatidic acid acyltransferase or LPAAT.

Organic cation transport proteins (OCTs) are a group of membrane transporters that facilitate the movement of organic cations across biological membranes. These transporters play an essential role in the absorption, distribution, and elimination of various endogenous and exogenous substances, including drugs and toxins.

There are four main types of OCTs, namely OCT1, OCT2, OCT3, and OCTN1 (also known as novel organic cation transporter 1 or OCT6). These proteins belong to the solute carrier (SLC) family, specifically SLC22A.

OCTs have a broad substrate specificity and can transport various organic cations, such as neurotransmitters (e.g., serotonin, dopamine, histamine), endogenous compounds (e.g., creatinine, choline), and drugs (e.g., metformin, quinidine, morphine). The transport process is typically sodium-independent and can occur in both directions, depending on the concentration gradient of the substrate.

OCTs are widely expressed in various tissues, including the liver, kidney, intestine, brain, heart, and placenta. Their expression patterns and functions vary among different OCT types, contributing to their diverse roles in physiology and pharmacology. Dysfunction of OCTs has been implicated in several diseases, such as drug toxicity, neurodegenerative disorders, and cancer.

In summary, organic cation transport proteins are membrane transporters that facilitate the movement of organic cations across biological membranes, playing crucial roles in the absorption, distribution, and elimination of various substances, including drugs and toxins.

Esterification is a chemical reaction that involves the conversion of an alcohol and a carboxylic acid into an ester, typically through the removal of a molecule of water. This reaction is often catalyzed by an acid or a base, and it is a key process in organic chemistry. Esters are commonly found in nature and are responsible for the fragrances of many fruits and flowers. They are also important in the production of various industrial and consumer products, including plastics, resins, and perfumes.

Fatty acids are carboxylic acids with a long aliphatic chain, which are important components of lipids and are widely distributed in living organisms. They can be classified based on the length of their carbon chain, saturation level (presence or absence of double bonds), and other structural features.

The two main types of fatty acids are:

1. Saturated fatty acids: These have no double bonds in their carbon chain and are typically solid at room temperature. Examples include palmitic acid (C16:0) and stearic acid (C18:0).
2. Unsaturated fatty acids: These contain one or more double bonds in their carbon chain and can be further classified into monounsaturated (one double bond) and polyunsaturated (two or more double bonds) fatty acids. Examples of unsaturated fatty acids include oleic acid (C18:1, monounsaturated), linoleic acid (C18:2, polyunsaturated), and alpha-linolenic acid (C18:3, polyunsaturated).

Fatty acids play crucial roles in various biological processes, such as energy storage, membrane structure, and cell signaling. Some essential fatty acids cannot be synthesized by the human body and must be obtained through dietary sources.

Palmitoylcarnitine is a type of acylcarnitine, which is an ester formed from carnitine and a fatty acid. Specifically, palmitoylcarnitine consists of the long-chain fatty acid palmitate (a 16-carbon saturated fatty acid) linked to carnitine through an ester bond.

In the human body, palmitoylcarnitine plays a crucial role in the transport and metabolism of long-chain fatty acids within mitochondria, the energy-producing organelles found in cells. The process involves converting palmitate into palmitoylcarnitine by an enzyme called carnitine palmitoyltransferase I (CPT-I) in the outer mitochondrial membrane. Palmitoylcarnitine is then transported across the inner mitochondrial membrane via a specific transporter, where it is converted back to palmitate by another enzyme called carnitine palmitoyltransferase II (CPT-II). The palmitate can then undergo beta-oxidation, a process that generates energy in the form of ATP.

Abnormal levels of palmitoylcarnitine in blood or other bodily fluids may indicate an underlying metabolic disorder, such as defects in fatty acid oxidation or carnitine transport. These conditions can lead to various symptoms, including muscle weakness, cardiomyopathy, and developmental delays.

Acylation is a medical and biological term that refers to the process of introducing an acyl group (-CO-) into a molecule. This process can occur naturally or it can be induced through chemical reactions. In the context of medicine and biology, acylation often occurs during post-translational modifications of proteins, where an acyl group is added to specific amino acid residues, altering the protein's function, stability, or localization.

An example of acylation in medicine is the administration of neuraminidase inhibitors, such as oseltamivir (Tamiflu), for the treatment and prevention of influenza. These drugs work by inhibiting the activity of the viral neuraminidase enzyme, which is essential for the release of newly formed virus particles from infected cells. Oseltamivir is administered orally as an ethyl ester prodrug, which is then hydrolyzed in the body to form the active acylated metabolite that inhibits the viral neuraminidase.

In summary, acylation is a vital process in medicine and biology, with implications for drug design, protein function, and post-translational modifications.

Coenzyme A, often abbreviated as CoA or sometimes holo-CoA, is a coenzyme that plays a crucial role in several important chemical reactions in the body, particularly in the metabolism of carbohydrates, fatty acids, and amino acids. It is composed of a pantothenic acid (vitamin B5) derivative called pantothenate, an adenosine diphosphate (ADP) molecule, and a terminal phosphate group.

Coenzyme A functions as a carrier molecule for acetyl groups, which are formed during the breakdown of carbohydrates, fatty acids, and some amino acids. The acetyl group is attached to the sulfur atom in CoA, forming acetyl-CoA, which can then be used as a building block for various biochemical pathways, such as the citric acid cycle (Krebs cycle) and fatty acid synthesis.

In summary, Coenzyme A is a vital coenzyme that helps facilitate essential metabolic processes by carrying and transferring acetyl groups in the body.

Cholesteryl esters are formed when cholesterol, a type of lipid (fat) that is important for the normal functioning of the body, becomes combined with fatty acids through a process called esterification. This results in a compound that is more hydrophobic (water-repelling) than cholesterol itself, which allows it to be stored more efficiently in the body.

Cholesteryl esters are found naturally in foods such as animal fats and oils, and they are also produced by the liver and other cells in the body. They play an important role in the structure and function of cell membranes, and they are also precursors to the synthesis of steroid hormones, bile acids, and vitamin D.

However, high levels of cholesteryl esters in the blood can contribute to the development of atherosclerosis, a condition characterized by the buildup of plaque in the arteries, which can increase the risk of heart disease and stroke. Cholesteryl esters are typically measured as part of a lipid profile, along with other markers such as total cholesterol, HDL cholesterol, and triglycerides.

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.

Triglycerides are the most common type of fat in the body, and they're found in the food we eat. They're carried in the bloodstream to provide energy to the cells in our body. High levels of triglycerides in the blood can increase the risk of heart disease, especially in combination with other risk factors such as high LDL (bad) cholesterol, low HDL (good) cholesterol, and high blood pressure.

It's important to note that while triglycerides are a type of fat, they should not be confused with cholesterol, which is a waxy substance found in the cells of our body. Both triglycerides and cholesterol are important for maintaining good health, but high levels of either can increase the risk of heart disease.

Triglyceride levels are measured through a blood test called a lipid panel or lipid profile. A normal triglyceride level is less than 150 mg/dL. Borderline-high levels range from 150 to 199 mg/dL, high levels range from 200 to 499 mg/dL, and very high levels are 500 mg/dL or higher.

Elevated triglycerides can be caused by various factors such as obesity, physical inactivity, excessive alcohol consumption, smoking, and certain medical conditions like diabetes, hypothyroidism, and kidney disease. Medications such as beta-blockers, steroids, and diuretics can also raise triglyceride levels.

Lifestyle changes such as losing weight, exercising regularly, eating a healthy diet low in saturated and trans fats, avoiding excessive alcohol consumption, and quitting smoking can help lower triglyceride levels. In some cases, medication may be necessary to reduce triglycerides to recommended levels.

I'd be happy to help! However, I believe there might be a slight misunderstanding in your question. Mitochondria are organelles found in the cells of all complex living organisms, including humans, while the liver is a large, solid organ located in the upper right portion of the abdomen. They don't have a medical definition together. I can certainly provide you with separate definitions for each:

1. Mitochondria: These are double-membrane-bound cellular organelles that generate most of the chemical energy needed to power the cell's biochemical reactions. Commonly known as the "powerhouse of the cell," mitochondria convert organic substrates, such as glucose, fatty acids, and amino acids, into adenosine triphosphate (ATP) through a process called oxidative phosphorylation. Mitochondria are dynamic structures that can change their shape, size, and number through fission (division) and fusion (merging) processes. They play essential roles in various cellular functions, including calcium signaling, apoptosis (programmed cell death), and the regulation of cellular metabolism.

2. Liver: The liver is a large, lobulated organ that lies mainly in the upper right portion of the abdominal cavity, just below the diaphragm. It plays a crucial role in various physiological functions, such as detoxification, protein synthesis, metabolism, and nutrient storage. The liver is responsible for removing toxins from the bloodstream, producing bile to aid in digestion, regulating glucose levels, synthesizing plasma proteins, and storing glycogen, vitamins, and minerals. It also contributes to the metabolism of carbohydrates, lipids, and amino acids, helping maintain energy homeostasis in the body.

I hope this clarifies any confusion! If you have any further questions or need more information, please don't hesitate to ask.

Cholesterol is a type of lipid (fat) molecule that is an essential component of cell membranes and is also used to make certain hormones and vitamins in the body. It is produced by the liver and is also obtained from animal-derived foods such as meat, dairy products, and eggs.

Cholesterol does not mix with blood, so it is transported through the bloodstream by lipoproteins, which are particles made up of both lipids and proteins. There are two main types of lipoproteins that carry cholesterol: low-density lipoproteins (LDL), also known as "bad" cholesterol, and high-density lipoproteins (HDL), also known as "good" cholesterol.

High levels of LDL cholesterol in the blood can lead to a buildup of cholesterol in the walls of the arteries, increasing the risk of heart disease and stroke. On the other hand, high levels of HDL cholesterol are associated with a lower risk of these conditions because HDL helps remove LDL cholesterol from the bloodstream and transport it back to the liver for disposal.

It is important to maintain healthy levels of cholesterol through a balanced diet, regular exercise, and sometimes medication if necessary. Regular screening is also recommended to monitor cholesterol levels and prevent health complications.

Glycerophosphates are esters of glycerol and phosphoric acid. In the context of biochemistry and medicine, glycerophosphates often refer to glycerol 3-phosphate (also known as glyceraldehyde 3-phosphate or glycerone phosphate) and its derivatives.

Glycerol 3-phosphate plays a crucial role in cellular metabolism, particularly in the process of energy production and storage. It is an important intermediate in both glycolysis (the breakdown of glucose to produce energy) and gluconeogenesis (the synthesis of glucose from non-carbohydrate precursors).

In addition, glycerophosphates are also involved in the formation of phospholipids, a major component of cell membranes. The esterification of glycerol 3-phosphate with fatty acids leads to the synthesis of phosphatidic acid, which is a key intermediate in the biosynthesis of other phospholipids.

Abnormalities in glycerophosphate metabolism have been implicated in various diseases, including metabolic disorders and neurological conditions.

Apolipoprotein A-I (ApoA-I) is a major protein component of high-density lipoproteins (HDL) in human plasma. It plays a crucial role in the metabolism and transport of lipids, particularly cholesterol, within the body. ApoA-I facilitates the formation of HDL particles, which are involved in the reverse transport of cholesterol from peripheral tissues to the liver for excretion. This process is known as reverse cholesterol transport and helps maintain appropriate cholesterol levels in the body. Low levels of ApoA-I or dysfunctional ApoA-I have been associated with an increased risk of developing cardiovascular diseases.

Betaine, also known as trimethylglycine, is a naturally occurring compound that can be found in various foods such as beets, spinach, and whole grains. In the body, betaine functions as an osmolyte, helping to regulate water balance in cells, and as a methyl donor, contributing to various metabolic processes including the conversion of homocysteine to methionine.

In medical terms, betaine is also used as a dietary supplement and medication. Betaine hydrochloride is a form of betaine that is sometimes used as a supplement to help with digestion by providing additional stomach acid. Betaine anhydrous, on the other hand, is often used as a supplement for improving athletic performance and promoting liver health.

Betaine has also been studied for its potential role in protecting against various diseases, including cardiovascular disease, diabetes, and neurological disorders. However, more research is needed to fully understand its mechanisms of action and therapeutic potential.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Microsomes are subcellular membranous vesicles that are obtained as a byproduct during the preparation of cellular homogenates. They are not naturally occurring structures within the cell, but rather formed due to fragmentation of the endoplasmic reticulum (ER) during laboratory procedures. Microsomes are widely used in various research and scientific studies, particularly in the fields of biochemistry and pharmacology.

Microsomes are rich in enzymes, including the cytochrome P450 system, which is involved in the metabolism of drugs, toxins, and other xenobiotics. These enzymes play a crucial role in detoxifying foreign substances and eliminating them from the body. As such, microsomes serve as an essential tool for studying drug metabolism, toxicity, and interactions, allowing researchers to better understand and predict the effects of various compounds on living organisms.

Retinol O-fatty-acyltransferase is not a widely recognized or established term in medical literature. However, I can provide information on the related concepts that might help you understand the term.

The enzyme likely being referred to here is lecithin-retinol acyltransferase (LRAT), which is involved in the visual cycle and is responsible for the esterification of retinol (vitamin A alcohol) into retinyl esters. This reaction occurs in the eye's pigment epithelium, where LRAT adds a fatty acid to retinol, forming retinyl palmitate, which is then stored in the retinal pigment epithelium (RPE).

The term "Retinol O-fatty-acyltransferase" seems to be an attempt to describe LRAT's function more generally. However, it is not a standard or widely accepted term for this enzyme in medical and scientific literature.

I am sorry for any confusion, but "Pentanoic Acids" is not a recognized medical term or concept. Pentanoic acid, also known as valeric acid, is an organic compound with the formula CH3CH2CH2CH2CO2H. It is a fatty acid with five carbon atoms, and it may have some uses in industry, but it does not have specific relevance to medical definition or healthcare.

Esters are organic compounds that are formed by the reaction between an alcohol and a carboxylic acid. They are widely found in nature and are used in various industries, including the production of perfumes, flavors, and pharmaceuticals. In the context of medical definitions, esters may be mentioned in relation to their use as excipients in medications or in discussions of organic chemistry and biochemistry. Esters can also be found in various natural substances such as fats and oils, which are triesters of glycerol and fatty acids.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Phosphatidylcholines (PtdCho) are a type of phospholipids that are essential components of cell membranes in living organisms. They are composed of a hydrophilic head group, which contains a choline moiety, and two hydrophobic fatty acid chains. Phosphatidylcholines are crucial for maintaining the structural integrity and function of cell membranes, and they also serve as important precursors for the synthesis of signaling molecules such as acetylcholine. They can be found in various tissues and biological fluids, including blood, and are abundant in foods such as soybeans, eggs, and meat. Phosphatidylcholines have been studied for their potential health benefits, including their role in maintaining healthy lipid metabolism and reducing the risk of cardiovascular disease.

Phospholipids are a major class of lipids that consist of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails. The head is composed of a phosphate group, which is often bound to an organic molecule such as choline, ethanolamine, serine or inositol. The tails are made up of two fatty acid chains.

Phospholipids are a key component of cell membranes and play a crucial role in maintaining the structural integrity and function of the cell. They form a lipid bilayer, with the hydrophilic heads facing outwards and the hydrophobic tails facing inwards, creating a barrier that separates the interior of the cell from the outside environment.

Phospholipids are also involved in various cellular processes such as signal transduction, intracellular trafficking, and protein function regulation. Additionally, they serve as emulsifiers in the digestive system, helping to break down fats in the diet.

Lipid metabolism is the process by which the body breaks down and utilizes lipids (fats) for various functions, such as energy production, cell membrane formation, and hormone synthesis. This complex process involves several enzymes and pathways that regulate the digestion, absorption, transport, storage, and consumption of fats in the body.

The main types of lipids involved in metabolism include triglycerides, cholesterol, phospholipids, and fatty acids. The breakdown of these lipids begins in the digestive system, where enzymes called lipases break down dietary fats into smaller molecules called fatty acids and glycerol. These molecules are then absorbed into the bloodstream and transported to the liver, which is the main site of lipid metabolism.

In the liver, fatty acids may be further broken down for energy production or used to synthesize new lipids. Excess fatty acids may be stored as triglycerides in specialized cells called adipocytes (fat cells) for later use. Cholesterol is also metabolized in the liver, where it may be used to synthesize bile acids, steroid hormones, and other important molecules.

Disorders of lipid metabolism can lead to a range of health problems, including obesity, diabetes, cardiovascular disease, and non-alcoholic fatty liver disease (NAFLD). These conditions may be caused by genetic factors, lifestyle habits, or a combination of both. Proper diagnosis and management of lipid metabolism disorders typically involves a combination of dietary changes, exercise, and medication.

Palmitic acid is a type of saturated fatty acid, which is a common component in many foods and also produced by the body. Its chemical formula is C16:0, indicating that it contains 16 carbon atoms and no double bonds. Palmitic acid is found in high concentrations in animal fats, such as butter, lard, and beef tallow, as well as in some vegetable oils, like palm kernel oil and coconut oil.

In the human body, palmitic acid can be synthesized from other substances or absorbed through the diet. It plays a crucial role in various biological processes, including energy storage, membrane structure formation, and signaling pathways regulation. However, high intake of palmitic acid has been linked to an increased risk of developing cardiovascular diseases due to its potential to raise low-density lipoprotein (LDL) cholesterol levels in the blood.

It is essential to maintain a balanced diet and consume palmitic acid-rich foods in moderation, along with regular exercise and a healthy lifestyle, to reduce the risk of chronic diseases.

Organosilicon compounds are a class of chemical compounds that contain at least one organic group (a group of atoms composed mainly of carbon and hydrogen) bonded to a silicon atom. The organic group can be an alkyl group, aryl group, or any other group that is derived from a hydrocarbon.

The term "organosilicon" is used to describe the covalent bond between carbon and silicon atoms, which is a type of bond known as a "sigma bond." This bond is formed by the overlap of atomic orbitals between the carbon and silicon atoms. The resulting organosilicon compound can have a wide range of physical and chemical properties, depending on the nature of the organic group and the number of such groups attached to the silicon atom.

Organosilicon compounds are widely used in various industries, including electronics, coatings, adhesives, and pharmaceuticals. They are also used as intermediates in the synthesis of other chemical compounds. Some common examples of organosilicon compounds include silicones, which are polymers that contain repeating units of siloxane (Si-O-Si) bonds, and organofunctional silanes, which are used as coupling agents to improve the adhesion of materials to surfaces.

High-Density Lipoproteins (HDL) are a type of lipoprotein that play a crucial role in the transportation and metabolism of cholesterol in the body. They are often referred to as "good" cholesterol because they help remove excess cholesterol from cells and carry it back to the liver, where it can be broken down and removed from the body. This process is known as reverse cholesterol transport.

HDLs are composed of a lipid core containing cholesteryl esters and triglycerides, surrounded by a shell of phospholipids, free cholesterol, and apolipoproteins, primarily apoA-I. The size and composition of HDL particles can vary, leading to the classification of different subclasses of HDL with varying functions and metabolic fates.

Elevated levels of HDL have been associated with a lower risk of developing cardiovascular diseases, while low HDL levels increase the risk. However, it is essential to consider that HDL function and quality may be more important than just the quantity in determining cardiovascular risk.

Dihydroxyacetone Phosphate (DHAP) is a 3-carbon organic compound that plays a crucial role in the metabolic pathway called glycolysis. It is an intermediate molecule formed during the conversion of glucose into pyruvate, which ultimately produces energy in the form of ATP.

In the glycolytic process, DHAP is produced from glyceraldehyde 3-phosphate (G3P) in a reaction catalyzed by the enzyme triose phosphate isomerase. Then, DHAP is converted back to G3P in a subsequent step, which prepares it for further processing in the glycolytic pathway. This reversible conversion of DHAP and G3P helps maintain the equilibrium of the glycolytic process.

Apart from its role in energy metabolism, DHAP is also involved in other biochemical processes, such as the synthesis of glucose during gluconeogenesis and the formation of lipids in the liver.

"Penicillium chrysogenum" is a species of filamentous fungi that is commonly found in the environment, particularly in soil and decaying vegetation. It is a member of the genus Penicillium, which includes several species that are known for their ability to produce penicillin, a group of antibiotics used to treat various bacterial infections.

"Penicillium chrysogenum" is one of the most important industrial producers of penicillin. It was originally identified as a separate species from "Penicillium notatum," which was the first species discovered to produce penicillin, but it is now considered to be a strain or variety of "Penicillium rubrum" or "Penicillium camemberti."

The fungus produces penicillin as a secondary metabolite, which means that it is not essential for the growth and development of the organism. Instead, penicillin is produced under certain conditions, such as nutrient limitation, to help the fungus compete with other microorganisms in its environment.

In addition to its medical importance, "Penicillium chrysogenum" also has industrial applications in the production of enzymes and other biomolecules. However, it can also cause food spoilage and allergic reactions in some individuals, so it is important to handle this organism with care.

Microbodies are small, membrane-bound organelles found in the cells of eukaryotic organisms. They typically measure between 0.2 to 0.5 micrometers in diameter and play a crucial role in various metabolic processes, particularly in the detoxification of harmful substances and the synthesis of lipids.

There are several types of microbodies, including:

1. Peroxisomes: These are the most common type of microbody. They contain enzymes that help break down fatty acids and amino acids, producing hydrogen peroxide as a byproduct. Another set of enzymes within peroxisomes then converts the harmful hydrogen peroxide into water and oxygen, thus detoxifying the cell.
2. Glyoxysomes: These microbodies are primarily found in plants and some fungi. They contain enzymes involved in the glyoxylate cycle, a metabolic pathway that helps convert stored fats into carbohydrates during germination.
3. Microbody-like particles (MLPs): These are smaller organelles found in certain protists and algae. Their functions are not well understood but are believed to be involved in lipid metabolism.

It is important to note that microbodies do not have a uniform structure or function across all eukaryotic cells, and their specific roles can vary depending on the organism and cell type.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

Inborn errors of lipid metabolism refer to genetic disorders that affect the body's ability to break down and process lipids (fats) properly. These disorders are caused by defects in genes that code for enzymes or proteins involved in lipid metabolism. As a result, toxic levels of lipids or their intermediates may accumulate in the body, leading to various health issues, which can include neurological problems, liver dysfunction, muscle weakness, and cardiovascular disease.

There are several types of inborn errors of lipid metabolism, including:

1. Disorders of fatty acid oxidation: These disorders affect the body's ability to convert long-chain fatty acids into energy, leading to muscle weakness, hypoglycemia, and cardiomyopathy. Examples include medium-chain acyl-CoA dehydrogenase deficiency (MCAD) and very long-chain acyl-CoA dehydrogenase deficiency (VLCAD).
2. Disorders of cholesterol metabolism: These disorders affect the body's ability to process cholesterol, leading to an accumulation of cholesterol or its intermediates in various tissues. Examples include Smith-Lemli-Opitz syndrome and lathosterolosis.
3. Disorders of sphingolipid metabolism: These disorders affect the body's ability to break down sphingolipids, leading to an accumulation of these lipids in various tissues. Examples include Gaucher disease, Niemann-Pick disease, and Fabry disease.
4. Disorders of glycerophospholipid metabolism: These disorders affect the body's ability to break down glycerophospholipids, leading to an accumulation of these lipids in various tissues. Examples include rhizomelic chondrodysplasia punctata and abetalipoproteinemia.

Inborn errors of lipid metabolism are typically diagnosed through genetic testing and biochemical tests that measure the activity of specific enzymes or the levels of specific lipids in the body. Treatment may include dietary modifications, supplements, enzyme replacement therapy, or gene therapy, depending on the specific disorder and its severity.

Oleic acid is a monounsaturated fatty acid that is commonly found in various natural oils such as olive oil, sunflower oil, and grapeseed oil. Its chemical formula is cis-9-octadecenoic acid, and it is a colorless liquid at room temperature. Oleic acid is an important component of human diet and has been shown to have potential health benefits, including reducing the risk of heart disease and improving immune function. It is also used in the manufacture of soaps, cosmetics, and other personal care products.

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.

Epoxy compounds, also known as epoxy resins, are a type of thermosetting polymer characterized by the presence of epoxide groups in their molecular structure. An epoxide group is a chemical functional group consisting of an oxygen atom double-bonded to a carbon atom, which is itself bonded to another carbon atom.

Epoxy compounds are typically produced by reacting a mixture of epichlorohydrin and bisphenol-A or other similar chemicals under specific conditions. The resulting product is a two-part system consisting of a resin and a hardener, which must be mixed together before use.

Once the two parts are combined, a chemical reaction takes place that causes the mixture to cure or harden into a solid material. This curing process can be accelerated by heat, and once fully cured, epoxy compounds form a strong, durable, and chemically resistant material that is widely used in various industrial and commercial applications.

In the medical field, epoxy compounds are sometimes used as dental restorative materials or as adhesives for bonding medical devices or prosthetics. However, it's important to note that some people may have allergic reactions to certain components of epoxy compounds, so their use must be carefully evaluated and monitored in a medical context.

Microsomes, liver refers to a subcellular fraction of liver cells (hepatocytes) that are obtained during tissue homogenization and subsequent centrifugation. These microsomal fractions are rich in membranous structures known as the endoplasmic reticulum (ER), particularly the rough ER. They are involved in various important cellular processes, most notably the metabolism of xenobiotics (foreign substances) including drugs, toxins, and carcinogens.

The liver microsomes contain a variety of enzymes, such as cytochrome P450 monooxygenases, that are crucial for phase I drug metabolism. These enzymes help in the oxidation, reduction, or hydrolysis of xenobiotics, making them more water-soluble and facilitating their excretion from the body. Additionally, liver microsomes also host other enzymes involved in phase II conjugation reactions, where the metabolites from phase I are further modified by adding polar molecules like glucuronic acid, sulfate, or acetyl groups.

In summary, liver microsomes are a subcellular fraction of liver cells that play a significant role in the metabolism and detoxification of xenobiotics, contributing to the overall protection and maintenance of cellular homeostasis within the body.

Lysophosphatidylcholines (LPCs) are a type of glycerophospholipids, which are major components of cell membranes. They are formed by the hydrolysis of phosphatidylcholines, another type of glycerophospholipids, catalyzed by the enzyme phospholipase A2. LPCs contain a single fatty acid chain attached to a glycerol backbone and a choline headgroup.

In medical terms, LPCs have been implicated in various physiological and pathological processes, such as cell signaling, membrane remodeling, and inflammation. Elevated levels of LPCs have been found in several diseases, including cardiovascular disease, neurodegenerative disorders, and cancer. They can also serve as biomarkers for the diagnosis and prognosis of these conditions.

Ketone bodies, also known as ketones or ketoacids, are organic compounds that are produced by the liver during the metabolism of fats when carbohydrate intake is low. They include acetoacetate (AcAc), beta-hydroxybutyrate (BHB), and acetone. These molecules serve as an alternative energy source for the body, particularly for the brain and heart, when glucose levels are insufficient to meet energy demands.

In a healthy individual, ketone bodies are present in low concentrations; however, during periods of fasting, starvation, or intense physical exertion, ketone production increases significantly. In some pathological conditions like uncontrolled diabetes mellitus, the body may produce excessive amounts of ketones, leading to a dangerous metabolic state called diabetic ketoacidosis (DKA).

Elevated levels of ketone bodies can be detected in blood or urine and are often used as an indicator of metabolic status. Monitoring ketone levels is essential for managing certain medical conditions, such as diabetes, where maintaining optimal ketone concentrations is crucial to prevent complications.

Caprylates are the salts or esters of capric acid, a saturated fatty acid with a chain length of 8 carbon atoms. In medical and biological contexts, caprylate refers to the anion (negatively charged ion) form of capric acid, which has the chemical formula C8H17O2-. Caprylates are used in various applications, including as food additives, pharmaceuticals, and personal care products.

Some examples of caprylate compounds include:

* Sodium caprylate (sodium octanoate): a sodium salt commonly used as a preservative and flavor enhancer in foods.
* Calcium caprylate (calcium octanoate): a calcium salt used as an emulsifier in food products and as a stabilizer in cosmetics.
* Caprylic acid/caprylate triglycerides: esters of glycerin with caprylic acid, used as emollients and solvents in skin care products and pharmaceuticals.

Caprylates have antimicrobial properties against certain bacteria, fungi, and viruses, making them useful in various medical applications. For instance, sodium caprylate is sometimes used as an antifungal agent to treat conditions like candidiasis (yeast infections). However, more research is needed to fully understand the potential benefits and risks of using caprylates for medicinal purposes.

"Palmitates" are salts or esters of palmitic acid, a saturated fatty acid that is commonly found in animals and plants. Palmitates can be found in various substances, including cosmetics, food additives, and medications. For example, sodium palmitate is a common ingredient in soaps and detergents, while retinyl palmitate is a form of vitamin A used in skin care products and dietary supplements.

In a medical context, "palmitates" may be mentioned in the results of laboratory tests that measure lipid metabolism or in discussions of nutrition and dietary fats. However, it is important to note that "palmitates" themselves are not typically a focus of medical diagnosis or treatment, but rather serve as components of various substances that may have medical relevance.

Vitamin B deficiency refers to a condition where an individual's body lacks adequate amounts of one or more essential Vitamin B compounds, including Vitamin B1 (thiamin), Vitamin B2 (riboflavin), Vitamin B3 (niacin), Vitamin B5 (pantothenic acid), Vitamin B6 (pyridoxine), Vitamin B7 (biotin), Vitamin B9 (folate), and Vitamin B12 (cobalamin). These water-soluble vitamins play crucial roles in various bodily functions, such as energy production, nerve function, DNA repair, and the formation of red blood cells.

Deficiency in any of these Vitamin B compounds can lead to specific health issues. For instance:

1. Vitamin B1 (thiamin) deficiency can cause beriberi, a condition characterized by muscle weakness, peripheral neuropathy, and heart failure.
2. Vitamin B2 (riboflavin) deficiency may result in ariboflavinosis, which presents with inflammation of the mouth and tongue, anemia, and skin disorders.
3. Vitamin B3 (niacin) deficiency can lead to pellagra, marked by diarrhea, dermatitis, dementia, and, if left untreated, death.
4. Vitamin B5 (pantothenic acid) deficiency is rare but can cause acne-like skin lesions and neurological symptoms.
5. Vitamin B6 (pyridoxine) deficiency may result in anemia, peripheral neuropathy, seizures, and skin disorders.
6. Vitamin B7 (biotin) deficiency can cause hair loss, skin rashes, and neurological symptoms.
7. Vitamin B9 (folate) deficiency can lead to megaloblastic anemia, neural tube defects in fetuses during pregnancy, and increased homocysteine levels, which may contribute to cardiovascular disease.
8. Vitamin B12 (cobalamin) deficiency can cause pernicious anemia, characterized by fatigue, weakness, neurological symptoms, and, if left untreated, irreversible nerve damage.

Deficiencies in these vitamins can arise from inadequate dietary intake, malabsorption syndromes, or certain medications that interfere with absorption or metabolism. It is essential to maintain a balanced diet and consider supplementation if necessary under the guidance of a healthcare professional.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Starvation is a severe form of malnutrition, characterized by insufficient intake of calories and nutrients to meet the body's energy requirements. This leads to a catabolic state where the body begins to break down its own tissues for energy, resulting in significant weight loss, muscle wasting, and weakness. Prolonged starvation can also lead to serious medical complications such as organ failure, electrolyte imbalances, and even death. It is typically caused by a lack of access to food due to poverty, famine, or other social or economic factors, but can also be a result of severe eating disorders such as anorexia nervosa.

Oleic acid is a monounsaturated fatty acid that is commonly found in various natural oils such as olive oil, sunflower oil, and peanut oil. Its chemical formula is cis-9-octadecenoic acid, and it is a colorless liquid at room temperature with a slight odor. Oleic acid is an important component of human diet and has been shown to have various health benefits, including reducing the risk of heart disease and improving immune function. It is also used in the manufacture of soaps, cosmetics, and other industrial products.

Lipids are a broad group of organic compounds that are insoluble in water but soluble in nonpolar organic solvents. They include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids. Lipids serve many important functions in the body, including energy storage, acting as structural components of cell membranes, and serving as signaling molecules. High levels of certain lipids, particularly cholesterol and triglycerides, in the blood are associated with an increased risk of cardiovascular disease.

Dithionitrobenzoic acid is not a medical term, as it is related to chemistry rather than medicine. It is an organic compound with the formula C6H4N2O4S2. This compound is a type of benzenediol that contains two sulfur atoms and two nitro groups. It is a white crystalline powder that is soluble in water and alcohol.

Dithionitrobenzoic acid is not used directly in medical applications, but it can be used as a reagent in chemical reactions that are relevant to medical research or analysis. For example, it can be used to determine the concentration of iron in biological samples through a reaction that produces a colored complex. However, if you have any specific questions related to its use or application in a medical context, I would recommend consulting with a medical professional or a researcher in the relevant field.

I believe you may be asking for a medical explanation or examples of substances that are referred to as "waxes." Waxes are not a specific medical term, but they can refer to various natural or synthetic esters that are insoluble in water and have a soft, waxy consistency. In a medical context, the term "waxes" might refer to:

1. Cerumen (Earwax): A yellowish waxy substance produced by glands in the ear canal. Cerumen helps protect the ear by trapping dirt, dust, and other particles and preventing them from entering the inner ear.
2. Sebaceous Waxes: These are esters found in sebum, an oily substance produced by sebaceous glands in the skin. Sebum helps keep the skin and hair moisturized and protected.
3. Cutaneous Waxes: These are lipid-rich substances secreted by specialized sweat glands called eccrine glands. They help to waterproof and protect the skin.
4. Histological Waxes: Paraffin or other waxes used in histology for tissue processing, embedding, and microtomy to prepare thin sections of tissues for examination under a microscope.

These are some examples of substances that can be referred to as "waxes" in a medical context.

Coenzyme A (CoA) ligases, also known as CoA synthetases, are a class of enzymes that activate acyl groups, such as fatty acids and amino acids, by forming a thioester bond with coenzyme A. This activation is an essential step in various metabolic pathways, including fatty acid oxidation, amino acid catabolism, and the synthesis of several important compounds like steroids and acetylcholine.

CoA ligases catalyze the following reaction:

acyl group + ATP + CoA ↔ acyl-CoA + AMP + PP~i~

In this reaction, an acyl group (R-) from a carboxylic acid is linked to the thiol (-SH) group of coenzyme A through a high-energy thioester bond. The energy required for this activation is provided by the hydrolysis of ATP to AMP and inorganic pyrophosphate (PP~i~).

CoA ligases are classified into three main types based on the nature of the acyl group they activate:

1. Acyl-CoA synthetases (or long-chain fatty acid CoA ligases) activate long-chain fatty acids, typically containing 12 or more carbon atoms.
2. Aminoacyl-CoA synthetases activate amino acids to form aminoacyl-CoAs, which are essential intermediates in the catabolism of certain amino acids.
3. Short-chain specific CoA ligases activate short-chain fatty acids (up to 6 carbon atoms) and other acyl groups like acetate or propionate.

These enzymes play a crucial role in maintaining cellular energy homeostasis, metabolism, and the synthesis of various essential biomolecules.

Lipoproteins are complex particles composed of multiple proteins and lipids (fats) that play a crucial role in the transport and metabolism of fat molecules in the body. They consist of an outer shell of phospholipids, free cholesterols, and apolipoproteins, enclosing a core of triglycerides and cholesteryl esters.

There are several types of lipoproteins, including:

1. Chylomicrons: These are the largest lipoproteins and are responsible for transporting dietary lipids from the intestines to other parts of the body.
2. Very-low-density lipoproteins (VLDL): Produced by the liver, VLDL particles carry triglycerides to peripheral tissues for energy storage or use.
3. Low-density lipoproteins (LDL): Often referred to as "bad cholesterol," LDL particles transport cholesterol from the liver to cells throughout the body. High levels of LDL in the blood can lead to plaque buildup in artery walls and increase the risk of heart disease.
4. High-density lipoproteins (HDL): Known as "good cholesterol," HDL particles help remove excess cholesterol from cells and transport it back to the liver for excretion or recycling. Higher levels of HDL are associated with a lower risk of heart disease.

Understanding lipoproteins and their roles in the body is essential for assessing cardiovascular health and managing risks related to heart disease and stroke.

Hypolipoproteinemias are a group of genetic disorders characterized by low levels of lipoproteins in the blood. Lipoproteins are complex particles composed of proteins and lipids that play a crucial role in the transport and metabolism of fat molecules, such as cholesterol and triglycerides, in the body.

There are several types of hypolipoproteinemias, each associated with deficiencies in specific lipoproteins:

1. Hypobetalipoproteinemia: This disorder is characterized by low levels of beta-lipoproteins, also known as low-density lipoproteins (LDL), or "bad" cholesterol. It can lead to decreased absorption of fat-soluble vitamins and an increased risk of fatty liver disease.
2. Abetalipoproteinemia: This is a rare autosomal recessive disorder characterized by the absence of beta-lipoproteins and apolipoprotein B, which results in very low levels of LDL cholesterol and high-density lipoproteins (HDL), or "good" cholesterol. It can lead to fat malabsorption, neurological symptoms, and retinal degeneration.
3. Tangier disease: This disorder is caused by a deficiency in apolipoprotein A-I and results in low levels of HDL cholesterol. It can cause enlarged orange-colored tonsils, neuropathy, and an increased risk of coronary artery disease.
4. Familial hypoalphalipoproteinemia: This disorder is characterized by low levels of HDL cholesterol due to a deficiency in apolipoprotein A-I or A-II. It can increase the risk of premature coronary artery disease.

It's important to note that while some hypolipoproteinemias are associated with an increased risk of cardiovascular disease, others may actually protect against it due to reduced levels of atherogenic lipoproteins. Treatment for these disorders typically involves dietary modifications and supplementation of fat-soluble vitamins and essential fatty acids. In some cases, medication may be necessary to manage symptoms or prevent complications.

Lysophospholipase is an enzyme that catalyzes the hydrolysis of a single fatty acid from lysophospholipids, producing a glycerophosphocholine and free fatty acid. This enzyme plays a role in the metabolism of lipids and membrane homeostasis. There are several types of lysophospholipases that differ based on their specificity for the head group of the lysophospholipid substrate, such as lysophosphatidylcholine-specific phospholipase or lysophospholipase 1 (LPLA1), and lysophosphatidic acid-specific phospholipase D or autotaxin (ATX).

Deficiency or mutations in lysophospholipases can lead to various diseases, such as LPI (lysophosphatidylinositol lipidosis) caused by a deficiency of the lysophospholipase superfamily member called Ptdlns-specific phospholipase C (PLC).

Note: This definition is for general information purposes only and may not include all the latest findings or medical terminologies. For accurate and comprehensive understanding, it's recommended to consult authoritative medical textbooks or resources.

Corneal opacity refers to a condition in which the cornea, the clear front part of the eye, becomes cloudy or opaque. This can occur due to various reasons such as injury, infection, degenerative changes, or inherited disorders. As a result, light is not properly refracted and vision becomes blurred or distorted. In some cases, corneal opacity can lead to complete loss of vision in the affected eye. Treatment options depend on the underlying cause and may include medication, corneal transplantation, or other surgical procedures.

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.

Palmitic acid is a type of saturated fatty acid, which is a common component in many foods and also produced naturally by the human body. Its chemical formula is C16H32O2. It's named after palm trees because it was first isolated from palm oil, although it can also be found in other vegetable oils, animal fats, and dairy products.

In the human body, palmitic acid plays a role in energy production and storage. However, consuming large amounts of this fatty acid has been linked to an increased risk of heart disease due to its association with elevated levels of bad cholesterol (LDL). The World Health Organization recommends limiting the consumption of saturated fats, including palmitic acid, to less than 10% of total energy intake.

Clofibrate is a medication that belongs to the class of drugs known as fibrates. It is primarily used to lower elevated levels of cholesterol and other fats (lipids) in the blood, specifically low-density lipoprotein (LDL), or "bad" cholesterol, and triglycerides, while increasing high-density lipoprotein (HDL), or "good" cholesterol. Clofibrate works by reducing the production of very-low-density lipoproteins (VLDL) in the liver, which in turn lowers triglyceride levels and indirectly reduces LDL cholesterol levels.

Clofibrate is available in oral tablet form and is typically prescribed for patients with high cholesterol or triglycerides who are at risk of cardiovascular disease, such as those with a history of heart attacks, strokes, or peripheral artery disease. It is important to note that clofibrate should be used in conjunction with lifestyle modifications, including a healthy diet, regular exercise, and smoking cessation.

Like all medications, clofibrate can have side effects, some of which may be serious. Common side effects include stomach upset, diarrhea, gas, and changes in taste. Less commonly, clofibrate can cause more severe side effects such as liver or muscle damage, gallstones, and an increased risk of developing certain types of cancer. Patients taking clofibrate should be monitored regularly by their healthcare provider to ensure that the medication is working effectively and to monitor for any potential side effects.

Apolipoproteins are a group of proteins that are associated with lipids (fats) in the body and play a crucial role in the metabolism, transportation, and regulation of lipids. They are structural components of lipoprotein particles, which are complexes of lipids and proteins that transport lipids in the bloodstream.

There are several types of apolipoproteins, including ApoA, ApoB, ApoC, ApoD, ApoE, and others. Each type has a specific function in lipid metabolism. For example, ApoA is a major component of high-density lipoprotein (HDL), often referred to as "good cholesterol," and helps remove excess cholesterol from cells and tissues and transport it to the liver for excretion. ApoB, on the other hand, is a major component of low-density lipoprotein (LDL), or "bad cholesterol," and plays a role in the delivery of cholesterol to cells and tissues.

Abnormal levels of apolipoproteins or dysfunctional forms of these proteins have been linked to various diseases, including cardiovascular disease, Alzheimer's disease, and metabolic disorders such as diabetes. Therefore, measuring apolipoprotein levels in the blood can provide valuable information for diagnosing and monitoring these conditions.

Medical Definition of Monoglycerides:

Monoglycerides are types of glycerides that contain one molecule of fatty acid combined with a glycerol molecule through an ester linkage. They are often used as food additives, serving as emulsifiers to help blend together water and oil-based ingredients in foods such as baked goods, ice cream, and chocolate. Monoglycerides can also be found naturally in some foods, including certain vegetable oils.

In the context of human physiology, monoglycerides can serve as a source of energy and can also play a role in the absorption and transport of fatty acids in the body. However, they are not typically considered to be a major nutrient or component of the human diet.

Apolipoprotein A (apoA) is a type of apolipoprotein that is primarily associated with high-density lipoproteins (HDL), often referred to as "good cholesterol." There are several subtypes of apoA, including apoA-I, apoA-II, and apoA-IV.

ApoA-I is the major protein component of HDL particles and plays a crucial role in reverse cholesterol transport, which is the process by which excess cholesterol is removed from tissues and delivered to the liver for excretion. Low levels of apoA-I have been linked to an increased risk of cardiovascular disease.

ApoA-II is another protein component of HDL particles, although its function is less well understood than that of apoA-I. Some studies suggest that apoA-II may play a role in regulating the metabolism of HDL particles.

ApoA-IV is found in both HDL and chylomicrons, which are lipoprotein particles that transport dietary lipids from the intestine to the liver. The function of apoA-IV is not well understood, but it may play a role in regulating appetite and energy metabolism.

Overall, apolipoproteins A are important components of HDL particles and play a critical role in maintaining healthy lipid metabolism and reducing the risk of cardiovascular disease.

Diacylglycerols (also known as diglycerides) are a type of glyceride, which is a compound that consists of glycerol and one or more fatty acids. Diacylglycerols contain two fatty acid chains bonded to a glycerol molecule through ester linkages. They are important intermediates in the metabolism of lipids and can be found in many types of food, including vegetable oils and dairy products. In the body, diacylglycerols can serve as a source of energy and can also play roles in cell signaling processes.

Ergothioneine is a naturally occurring antioxidant compound that is found in various foods such as mushrooms, some types of beans, and certain grains. It is also produced by some bacteria that live in the human body. Ergothioneine has been shown to have potential health benefits due to its antioxidant properties, which help protect cells from damage caused by free radicals. Some studies suggest that ergothioneine may have neuroprotective effects and could play a role in preventing neurodegenerative diseases such as Parkinson's and Alzheimer's. However, more research is needed to fully understand the potential health benefits of this compound.

Lipoylation is the post-translational modification of proteins by attaching lipoic acid (also known as α-lipoic acid or octanoic acid) to specific lysine residues in the protein. This process plays a crucial role in mitochondrial energy metabolism, particularly in the functioning of multi-enzyme complexes involved in the citric acid cycle and oxidative phosphorylation.

The lipoic acid cofactor is covalently attached to the target proteins by enzymes called lipoyltransferases. Once attached, lipoic acid can undergo reversible oxidation-reduction reactions, which facilitate the transfer of electrons and acetyl groups during metabolic processes. These redox reactions are essential for the proper functioning of critical mitochondrial enzymes such as pyruvate dehydrogenase complex (PDH), α-ketoglutarate dehydrogenase complex (KGDHC), and branched-chain ketoacid dehydrogenase complex (BCKDC).

Dysregulation of lipoylation has been implicated in various diseases, including neurodegenerative disorders, metabolic conditions, and cancer. Therefore, understanding the molecular mechanisms underlying lipoylation is important for developing potential therapeutic strategies to target these diseases.

Acetyl Coenzyme A, often abbreviated as Acetyl-CoA, is a key molecule in metabolism, particularly in the breakdown and oxidation of carbohydrates, fats, and proteins to produce energy. It is a coenzyme that plays a central role in the cellular process of transforming the energy stored in the chemical bonds of nutrients into a form that the cell can use.

Acetyl-CoA consists of an acetyl group (two carbon atoms) linked to coenzyme A, a complex organic molecule. This linkage is facilitated by an enzyme called acetyltransferase. Once formed, Acetyl-CoA can enter various metabolic pathways. In the citric acid cycle (also known as the Krebs cycle), Acetyl-CoA is further oxidized to release energy in the form of ATP, NADH, and FADH2, which are used in other cellular processes. Additionally, Acetyl-CoA is involved in the biosynthesis of fatty acids, cholesterol, and certain amino acids.

In summary, Acetyl Coenzyme A is a vital molecule in metabolism that connects various biochemical pathways for energy production and biosynthesis.

3-Hydroxybutyric acid, also known as β-hydroxybutyric acid, is a type of ketone body that is produced in the liver during the metabolism of fatty acids. It is a colorless, slightly water-soluble compound with a bitter taste and an unpleasant odor.

In the body, 3-hydroxybutyric acid is produced when there is not enough glucose available to meet the body's energy needs, such as during fasting, starvation, or prolonged intense exercise. It can also be produced in large amounts in people with uncontrolled diabetes, particularly during a condition called diabetic ketoacidosis.

3-Hydroxybutyric acid is an important source of energy for the brain and other organs during periods of low glucose availability. However, high levels of 3-hydroxybutyric acid in the blood can lead to a condition called ketosis, which can cause symptoms such as nausea, vomiting, abdominal pain, and confusion. If left untreated, ketosis can progress to diabetic ketoacidosis, a potentially life-threatening complication of diabetes.

Palmitoyl-CoA hydrolase is an enzyme that catalyzes the hydrolysis of palmitoyl-coenzyme A (palmitoyl-CoA) to produce free coenzyme A (CoA) and palmitic acid. Palmitoyl-CoA is a fatty acyl-CoA ester that plays a central role in lipid metabolism, particularly in the synthesis of complex lipids such as triacylglycerols and phospholipids.

The reaction catalyzed by palmitoyl-CoA hydrolase is:

palmitoyl-CoA + H2O → CoA + palmitic acid

This enzyme is important for regulating the levels of palmitoyl-CoA in cells and may play a role in the development of metabolic disorders such as obesity and non-alcoholic fatty liver disease. Palmitoyl-CoA hydrolase has also been studied as a potential target for the development of therapies to treat these conditions.

Biological transport refers to the movement of molecules, ions, or solutes across biological membranes or through cells in living organisms. This process is essential for maintaining homeostasis, regulating cellular functions, and enabling communication between cells. There are two main types of biological transport: passive transport and active transport.

Passive transport does not require the input of energy and includes:

1. Diffusion: The random movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.
2. Osmosis: The diffusion of solvent molecules (usually water) across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
3. Facilitated diffusion: The assisted passage of polar or charged substances through protein channels or carriers in the cell membrane, which increases the rate of diffusion without consuming energy.

Active transport requires the input of energy (in the form of ATP) and includes:

1. Primary active transport: The direct use of ATP to move molecules against their concentration gradient, often driven by specific transport proteins called pumps.
2. Secondary active transport: The coupling of the movement of one substance down its electrochemical gradient with the uphill transport of another substance, mediated by a shared transport protein. This process is also known as co-transport or counter-transport.

Acetyltransferases are a type of enzyme that facilitates the transfer of an acetyl group (a chemical group consisting of an acetyl molecule, which is made up of carbon, hydrogen, and oxygen atoms) from a donor molecule to a recipient molecule. This transfer of an acetyl group can modify the function or activity of the recipient molecule.

In the context of biology and medicine, acetyltransferases are important for various cellular processes, including gene expression, DNA replication, and protein function. For example, histone acetyltransferases (HATs) are a type of acetyltransferase that add an acetyl group to the histone proteins around which DNA is wound. This modification can alter the structure of the chromatin, making certain genes more or less accessible for transcription, and thereby influencing gene expression.

Abnormal regulation of acetyltransferases has been implicated in various diseases, including cancer, neurodegenerative disorders, and infectious diseases. Therefore, understanding the function and regulation of these enzymes is an important area of research in biomedicine.

Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).

Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.

Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.

Reye Syndrome is a rare but serious condition that primarily affects children and teenagers, particularly those who have recently recovered from viral infections such as chickenpox or flu. It is characterized by rapidly progressive encephalopathy (brain dysfunction) and fatty degeneration of the liver.

The exact cause of Reye Syndrome remains unknown, but it has been linked to the use of aspirin and other salicylate-containing medications during viral illnesses. The American Academy of Pediatrics recommends avoiding the use of aspirin in children and teenagers with chickenpox or flu-like symptoms due to this association.

Early symptoms of Reye Syndrome include persistent vomiting, diarrhea, and listlessness. As the condition progresses, symptoms can worsen and may include disorientation, seizures, coma, and even death in severe cases. Diagnosis is typically based on clinical presentation, laboratory tests, and sometimes a liver biopsy.

Treatment for Reye Syndrome involves supportive care, such as fluid and electrolyte management, addressing metabolic abnormalities, controlling intracranial pressure, and providing ventilatory support if necessary. Early recognition and intervention are crucial to improving outcomes in affected individuals.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

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.

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.

Medical Definition of Vitamin A:

Vitamin A is a fat-soluble vitamin that is essential for normal vision, immune function, and cell growth. It is also an antioxidant that helps protect the body's cells from damage caused by free radicals. Vitamin A can be found in two main forms: preformed vitamin A, which is found in animal products such as dairy, fish, and meat, particularly liver; and provitamin A carotenoids, which are found in plant-based foods such as fruits, vegetables, and vegetable oils.

The most active form of vitamin A is retinoic acid, which plays a critical role in the development and maintenance of the heart, lungs, kidneys, and other organs. Vitamin A deficiency can lead to night blindness, dry skin, and increased susceptibility to infections. Chronic vitamin A toxicity can cause nausea, dizziness, headaches, coma, and even death.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

Octoxynol is a type of surfactant, which is a compound that lowers the surface tension between two substances, such as oil and water. It is a synthetic chemical that is composed of repeating units of octylphenoxy polyethoxy ethanol.

Octoxynol is commonly used in medical applications as a spermicide, as it is able to disrupt the membrane of sperm cells and prevent them from fertilizing an egg. It is found in some contraceptive creams, gels, and films, and is also used as an ingredient in some personal care products such as shampoos and toothpastes.

In addition to its use as a spermicide, octoxynol has been studied for its potential antimicrobial properties, and has been shown to have activity against certain viruses, bacteria, and fungi. However, its use as an antimicrobial agent is not widely established.

It's important to note that octoxynol can cause irritation and allergic reactions in some people, and should be used with caution. Additionally, there is some concern about the potential for octoxynol to have harmful effects on the environment, as it has been shown to be toxic to aquatic organisms at high concentrations.

Lysophospholipids are a type of glycerophospholipid, which is a major component of cell membranes. They are characterized by having only one fatty acid chain attached to the glycerol backbone, as opposed to two in regular phospholipids. This results in a more polar and charged molecule, which can play important roles in cell signaling and regulation.

Lysophospholipids can be derived from the breakdown of regular phospholipids through the action of enzymes such as phospholipase A1 or A2. They can also be synthesized de novo in the cell. Some lysophospholipids, such as lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P), have been found to act as signaling molecules that bind to specific G protein-coupled receptors and regulate various cellular processes, including proliferation, survival, and migration.

Abnormal levels of lysophospholipids have been implicated in several diseases, such as cancer, inflammation, and neurological disorders. Therefore, understanding the biology of lysophospholipids has important implications for developing new therapeutic strategies.

Acyl Carrier Protein (ACP) is a small, acidic protein that plays a crucial role in the fatty acid synthesis process. It functions as a cofactor by carrying acyl groups during the elongation cycles of fatty acid chains. The ACP molecule has a characteristic prosthetic group known as 4'-phosphopantetheine, to which the acyl groups get attached covalently. This protein is highly conserved across different species and is essential for the production of fatty acids in both prokaryotic and eukaryotic organisms.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Thin-layer chromatography (TLC) is a type of chromatography used to separate, identify, and quantify the components of a mixture. In TLC, the sample is applied as a small spot onto a thin layer of adsorbent material, such as silica gel or alumina, which is coated on a flat, rigid support like a glass plate. The plate is then placed in a developing chamber containing a mobile phase, typically a mixture of solvents.

As the mobile phase moves up the plate by capillary action, it interacts with the stationary phase and the components of the sample. Different components of the mixture travel at different rates due to their varying interactions with the stationary and mobile phases, resulting in distinct spots on the plate. The distance each component travels can be measured and compared to known standards to identify and quantify the components of the mixture.

TLC is a simple, rapid, and cost-effective technique that is widely used in various fields, including forensics, pharmaceuticals, and research laboratories. It allows for the separation and analysis of complex mixtures with high resolution and sensitivity, making it an essential tool in many analytical applications.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

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.

Complementary DNA (cDNA) is a type of DNA that is synthesized from a single-stranded RNA molecule through the process of reverse transcription. In this process, the enzyme reverse transcriptase uses an RNA molecule as a template to synthesize a complementary DNA strand. The resulting cDNA is therefore complementary to the original RNA molecule and is a copy of its coding sequence, but it does not contain non-coding regions such as introns that are present in genomic DNA.

Complementary DNA is often used in molecular biology research to study gene expression, protein function, and other genetic phenomena. For example, cDNA can be used to create cDNA libraries, which are collections of cloned cDNA fragments that represent the expressed genes in a particular cell type or tissue. These libraries can then be screened for specific genes or gene products of interest. Additionally, cDNA can be used to produce recombinant proteins in heterologous expression systems, allowing researchers to study the structure and function of proteins that may be difficult to express or purify from their native sources.

Tissue distribution, in the context of pharmacology and toxicology, refers to the way that a drug or xenobiotic (a chemical substance found within an organism that is not naturally produced by or expected to be present within that organism) is distributed throughout the body's tissues after administration. It describes how much of the drug or xenobiotic can be found in various tissues and organs, and is influenced by factors such as blood flow, lipid solubility, protein binding, and the permeability of cell membranes. Understanding tissue distribution is important for predicting the potential effects of a drug or toxin on different parts of the body, and for designing drugs with improved safety and efficacy profiles.

Phosphatidic acids (PAs) are a type of phospholipid that are essential components of cell membranes. They are composed of a glycerol backbone linked to two fatty acid chains and a phosphate group. The phosphate group is esterified to another molecule, usually either serine, inositol, or choline, forming different types of phosphatidic acids.

PAs are particularly important as they serve as key regulators of many cellular processes, including signal transduction, membrane trafficking, and autophagy. They can act as signaling molecules by binding to and activating specific proteins, such as the enzyme phospholipase D, which generates second messengers involved in various signaling pathways.

PAs are also important intermediates in the synthesis of other phospholipids, such as phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol. They are produced by the enzyme diacylglycerol kinase (DGK), which adds a phosphate group to diacylglycerol (DAG) to form PA.

Abnormal levels of PAs have been implicated in various diseases, including cancer, diabetes, and neurological disorders. Therefore, understanding the regulation and function of PAs is an active area of research with potential therapeutic implications.

Nonesterified fatty acids (NEFA), also known as free fatty acids (FFA), refer to fatty acid molecules that are not bound to glycerol in the form of triglycerides or other esters. In the bloodstream, NEFAs are transported while bound to albumin and can serve as a source of energy for peripheral tissues. Under normal physiological conditions, NEFA levels are tightly regulated by the body; however, elevated NEFA levels have been associated with various metabolic disorders such as insulin resistance, obesity, and type 2 diabetes.

Ethylmaleimide is a chemical compound that is commonly used in research and scientific studies. Its chemical formula is C7H10N2S. It is known to modify proteins by forming covalent bonds with them, which can alter their function or structure. This property makes it a useful tool in the study of protein function and interactions.

In a medical context, Ethylmaleimide is not used as a therapeutic agent due to its reactivity and potential toxicity. However, it has been used in research to investigate various physiological processes, including the regulation of ion channels and the modulation of enzyme activity. It is important to note that the use of Ethylmaleimide in medical research should be carried out with appropriate precautions and safety measures due to its potential hazards.

Carbon radioisotopes are radioactive isotopes of carbon, which is an naturally occurring chemical element with the atomic number 6. The most common and stable isotope of carbon is carbon-12 (^12C), but there are also several radioactive isotopes, including carbon-11 (^11C), carbon-14 (^14C), and carbon-13 (^13C). These radioisotopes have different numbers of neutrons in their nuclei, which makes them unstable and causes them to emit radiation.

Carbon-11 has a half-life of about 20 minutes and is used in medical imaging techniques such as positron emission tomography (PET) scans. It is produced by bombarding nitrogen-14 with protons in a cyclotron.

Carbon-14, also known as radiocarbon, has a half-life of about 5730 years and is used in archaeology and geology to date organic materials. It is produced naturally in the atmosphere by cosmic rays.

Carbon-13 is stable and has a natural abundance of about 1.1% in carbon. It is not radioactive, but it can be used as a tracer in medical research and in the study of metabolic processes.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Polyketide synthases (PKSs) are a type of large, multifunctional enzymes found in bacteria, fungi, and other organisms. They play a crucial role in the biosynthesis of polyketides, which are a diverse group of natural products with various biological activities, including antibiotic, antifungal, anticancer, and immunosuppressant properties.

PKSs are responsible for the assembly of polyketide chains by repetitively adding two-carbon units derived from acetyl-CoA or other extender units to a growing chain. The PKS enzymes can be classified into three types based on their domain organization and mechanism of action: type I, type II, and type III PKSs.

Type I PKSs are large, modular enzymes that contain multiple domains responsible for different steps in the polyketide biosynthesis process. These include acyltransferase (AT) domains that load extender units onto the PKS, acyl carrier proteins (ACPs) that tether the growing chain to the PKS, and ketosynthase (KS) domains that catalyze the condensation of the extender unit with the growing chain.

Type II PKSs are simpler enzymes that consist of several separate proteins that work together in a complex to synthesize polyketides. These include ketosynthase, acyltransferase, and acyl carrier protein domains, as well as other domains responsible for reducing or modifying the polyketide chain.

Type III PKSs are the simplest of the three types and consist of a single catalytic domain that is responsible for both loading extender units and catalyzing their condensation with the growing chain. These enzymes typically synthesize shorter polyketide chains, such as those found in certain plant hormones and pigments.

Overall, PKSs are important enzymes involved in the biosynthesis of a wide range of natural products with significant medical and industrial applications.

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.

Membrane lipids are the main component of biological membranes, forming a lipid bilayer in which various cellular processes take place. These lipids include phospholipids, glycolipids, and cholesterol. Phospholipids are the most abundant type, consisting of a hydrophilic head (containing a phosphate group) and two hydrophobic tails (composed of fatty acid chains). Glycolipids contain a sugar group attached to the lipid molecule. Cholesterol helps regulate membrane fluidity and permeability. Together, these lipids create a selectively permeable barrier that separates cells from their environment and organelles within cells.

Lipoprotein-X (Lp-X) is a type of lipoprotein that is typically found in the blood under certain pathological conditions. Unlike other lipoproteins such as low-density lipoprotein (LDL) or high-density lipoprotein (HDL), Lp-X does not contain apolipoproteins and is not associated with cholesterol transport. Instead, Lp-X is rich in free cholesterol and phospholipids, and it can be formed when there is an increase in the concentration of these lipids in the blood due to the breakdown of cell membranes or other lipoproteins.

Lp-X is often found in the blood of patients with liver diseases such as cirrhosis or hepatitis, as well as in those with severe malnutrition or who have experienced massive trauma. It can also be present in the blood of pregnant women, particularly those with preeclampsia or HELLP syndrome.

Because Lp-X lacks apolipoproteins, it is not recognized by the liver and cannot be cleared from the blood efficiently. As a result, high levels of Lp-X can contribute to the development of fatty liver disease, inflammation, and other complications associated with liver dysfunction.

Phosphatidate phosphatase is an enzyme that plays a crucial role in the metabolism of lipids, particularly in the synthesis of glycerophospholipids, which are key components of cell membranes.

The term "phosphatidate" refers to a type of lipid molecule known as a diacylglycerol phosphate. This molecule contains two fatty acid chains attached to a glycerol backbone, with a phosphate group also attached to the glycerol.

Phosphatidate phosphatase functions to remove the phosphate group from phosphatidate, converting it into diacylglycerol (DAG). This reaction is an important step in the biosynthesis of glycerophospholipids, as DAG can be further metabolized to produce various types of these lipids, including phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol.

There are two main types of phosphatidate phosphatase enzymes: type 1 and type 2. Type 1 phosphatidate phosphatase is primarily located in the cytosol and is involved in the synthesis of triacylglycerols, which are stored as energy reserves in cells. Type 2 phosphatidate phosphatase, on the other hand, is found on the endoplasmic reticulum membrane and plays a key role in the biosynthesis of glycerophospholipids.

Deficiencies or mutations in phosphatidate phosphatase enzymes can lead to various metabolic disorders, including some forms of lipodystrophy, which are characterized by abnormalities in fat metabolism and distribution.

Subcellular fractions refer to the separation and collection of specific parts or components of a cell, including organelles, membranes, and other structures, through various laboratory techniques such as centrifugation and ultracentrifugation. These fractions can be used in further biochemical and molecular analyses to study the structure, function, and interactions of individual cellular components. Examples of subcellular fractions include nuclear extracts, mitochondrial fractions, microsomal fractions (membrane vesicles), and cytosolic fractions (cytoplasmic extracts).

A sterol esterase is an enzyme that catalyzes the hydrolysis of sterol esters, which are fatty acid esters of sterols (such as cholesterol) that are commonly found in lipoproteins and cell membranes. Sterol esterases play a crucial role in the metabolism of lipids by breaking down sterol esters into free sterols and free fatty acids, which can then be used in various biochemical processes.

There are several types of sterol esterases that have been identified, including:

1. Cholesteryl esterase (CE): This enzyme is responsible for hydrolyzing cholesteryl esters in the intestine and liver. It plays a critical role in the absorption and metabolism of dietary cholesterol.
2. Hormone-sensitive lipase (HSL): This enzyme is involved in the hydrolysis of sterol esters in adipose tissue, as well as other lipids such as triacylglycerols. It is regulated by hormones such as insulin and catecholamines.
3. Carboxylesterase (CES): This enzyme is a broad-specificity esterase that can hydrolyze various types of esters, including sterol esters. It is found in many tissues throughout the body.

Sterol esterases are important targets for drug development, as inhibiting these enzymes can have therapeutic effects in a variety of diseases, such as obesity, diabetes, and cardiovascular disease.

In medical terms, "seeds" are often referred to as a small amount of a substance, such as a radioactive material or drug, that is inserted into a tissue or placed inside a capsule for the purpose of treating a medical condition. This can include procedures like brachytherapy, where seeds containing radioactive materials are used in the treatment of cancer to kill cancer cells and shrink tumors. Similarly, in some forms of drug delivery, seeds containing medication can be used to gradually release the drug into the body over an extended period of time.

It's important to note that "seeds" have different meanings and applications depending on the medical context. In other cases, "seeds" may simply refer to small particles or structures found in the body, such as those present in the eye's retina.

Hydroxymethylglutaryl CoA (HMG-CoA) reductase is an enzyme that plays a crucial role in the synthesis of cholesterol in the body. It is found in the endoplasmic reticulum of cells and catalyzes the conversion of HMG-CoA to mevalonic acid, which is a key rate-limiting step in the cholesterol biosynthetic pathway.

The reaction catalyzed by HMG-CoA reductase is as follows:

HMG-CoA + 2 NADPH + 2 H+ → mevalonic acid + CoA + 2 NADP+

This enzyme is the target of statin drugs, which are commonly prescribed to lower cholesterol levels in the treatment of cardiovascular diseases. Statins work by inhibiting HMG-CoA reductase, thereby reducing the production of cholesterol in the body.

Hyperammonemia is a medical condition characterized by an excessively high level of ammonia (a toxic byproduct of protein metabolism) in the blood. This can lead to serious neurological symptoms and complications, as ammonia is highly toxic to the brain. Hyperammonemia can be caused by various underlying conditions, including liver disease, genetic disorders that affect ammonia metabolism, certain medications, and infections. It is important to diagnose and treat hyperammonemia promptly to prevent long-term neurological damage or even death. Treatment typically involves addressing the underlying cause of the condition, as well as providing supportive care such as administering medications that help remove ammonia from the blood.

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.

Lipase is an enzyme that is produced by the pancreas and found in the digestive system of most organisms. Its primary function is to catalyze the hydrolysis of fats (triglycerides) into smaller molecules, such as fatty acids and glycerol, which can then be absorbed by the intestines and utilized for energy or stored for later use.

In medical terms, lipase levels in the blood are often measured to diagnose or monitor conditions that affect the pancreas, such as pancreatitis (inflammation of the pancreas), pancreatic cancer, or cystic fibrosis. Elevated lipase levels may indicate damage to the pancreas and its ability to produce digestive enzymes.

Isoenzymes, also known as isoforms, are multiple forms of an enzyme that catalyze the same chemical reaction but differ in their amino acid sequence, structure, and/or kinetic properties. They are encoded by different genes or alternative splicing of the same gene. Isoenzymes can be found in various tissues and organs, and they play a crucial role in biological processes such as metabolism, detoxification, and cell signaling. Measurement of isoenzyme levels in body fluids (such as blood) can provide valuable diagnostic information for certain medical conditions, including tissue damage, inflammation, and various diseases.

Lipid A is the biologically active component of lipopolysaccharides (LPS), which are found in the outer membrane of Gram-negative bacteria. It is responsible for the endotoxic activity of LPS and plays a crucial role in the pathogenesis of gram-negative bacterial infections. Lipid A is a glycophosphatidylinositol (GPI) anchor, consisting of a glucosamine disaccharide backbone with multiple fatty acid chains and phosphate groups attached to it. It can induce the release of proinflammatory cytokines, fever, and other symptoms associated with sepsis when introduced into the bloodstream.

Low-density lipoproteins (LDL), also known as "bad cholesterol," are a type of lipoprotein that carry cholesterol and other fats from the liver to cells throughout the body. High levels of LDL in the blood can lead to the buildup of cholesterol in the walls of the arteries, which can increase the risk of heart disease and stroke.

Lipoproteins are complex particles composed of proteins (apolipoproteins) and lipids (cholesterol, triglycerides, and phospholipids) that are responsible for transporting fat molecules around the body in the bloodstream. LDL is one type of lipoprotein, along with high-density lipoproteins (HDL), very low-density lipoproteins (VLDL), and chylomicrons.

LDL particles are smaller than HDL particles and can easily penetrate the artery walls, leading to the formation of plaques that can narrow or block the arteries. Therefore, maintaining healthy levels of LDL in the blood is essential for preventing cardiovascular disease.

"Penicillium" is not a medical term per se, but it is a genus of mold that is widely used in the field of medicine, specifically in the production of antibiotics. Here's a scientific definition:

Penicillium is a genus of ascomycete fungi that are commonly found in the environment, particularly in soil, decaying vegetation, and food. Many species of Penicillium produce penicillin, a group of antibiotics with activity against gram-positive bacteria. The discovery and isolation of penicillin from Penicillium notatum by Alexander Fleming in 1928 revolutionized the field of medicine and led to the development of modern antibiotic therapy. Since then, various species of Penicillium have been used in the industrial production of penicillin and other antibiotics, as well as in the production of enzymes, organic acids, and other industrial products.

Apolipoprotein A-II (ApoA-II) is a protein component of high-density lipoproteins (HDL), often referred to as "good cholesterol." It is one of the major apolipoproteins in HDL and plays a role in the structure, metabolism, and function of HDL particles. ApoA-II is produced primarily in the liver and intestine and helps facilitate the transport of cholesterol from tissues to the liver for excretion. Additionally, ApoA-II has been shown to have anti-inflammatory properties and may play a role in the regulation of the immune response.

Clofibric acid is the main metabolic product of clofibrate, a medication that belongs to the class of drugs called fibrates. It works by lowering levels of total and LDL (low-density lipoprotein) cholesterol and triglycerides in the blood, while increasing HDL (high-density lipoprotein) cholesterol levels. Clofibric acid is an antihyperlipidemic agent that is used primarily for the treatment of hypertriglyceridemia and mixed dyslipidemia. It may also be used to prevent pancreatitis caused by high triglyceride levels.

Clofibric acid is detectable in the urine and can be used as a biomarker for clofibrate exposure or use. However, it's important to note that clofibrate has largely been replaced by newer fibrates and statins due to its adverse effects profile and lower efficacy compared to these newer agents.

Methylhydrazines are a class of organic compounds that contain a hydrazine functional group with one or more methyl substituents. Hydrazine is a simple inorganic compound with the formula N2H4, and it consists of a nitrogen atom bonded to four hydrogen atoms through nitrogen-hydrogen covalent bonds. When one or more of these hydrogens are replaced by a methyl group (CH3), we get methylhydrazines.

The most common methylhydrazine is monomethylhydrazine (MMH), which has the molecular formula CH6N2. It is an colorless, oily liquid with an ammonia-like odor and is highly toxic and reactive. MMH is used as a rocket propellant due to its high specific impulse and density.

Another example of methylhydrazine is unsymmetrical dimethylhydrazine (UDMH), which has the molecular formula C2H8N2. UDMH is also a colorless, oily liquid with an ammonia-like odor and is used as a rocket propellant.

It's important to note that methylhydrazines are highly toxic and reactive compounds, and they require careful handling and storage. They can cause harm to the skin, eyes, respiratory system, and nervous system, and prolonged exposure can lead to serious health effects or death.

Phospholipases are a group of enzymes that catalyze the hydrolysis of phospholipids, which are major components of cell membranes. Phospholipases cleave specific ester bonds in phospholipids, releasing free fatty acids and other lipophilic molecules. Based on the site of action, phospholipases are classified into four types:

1. Phospholipase A1 (PLA1): This enzyme hydrolyzes the ester bond at the sn-1 position of a glycerophospholipid, releasing a free fatty acid and a lysophospholipid.
2. Phospholipase A2 (PLA2): PLA2 cleaves the ester bond at the sn-2 position of a glycerophospholipid, releasing a free fatty acid (often arachidonic acid) and a lysophospholipid. Arachidonic acid is a precursor for eicosanoids, which are signaling molecules involved in inflammation and other physiological processes.
3. Phospholipase C (PLC): PLC hydrolyzes the phosphodiester bond in the headgroup of a glycerophospholipid, releasing diacylglycerol (DAG) and a soluble head group, such as inositol trisphosphate (IP3). DAG acts as a secondary messenger in intracellular signaling pathways, while IP3 mediates the release of calcium ions from intracellular stores.
4. Phospholipase D (PLD): PLD cleaves the phosphoester bond between the headgroup and the glycerol moiety of a glycerophospholipid, releasing phosphatidic acid (PA) and a free head group. PA is an important signaling molecule involved in various cellular processes, including membrane trafficking, cytoskeletal reorganization, and cell survival.

Phospholipases have diverse roles in normal physiology and pathophysiological conditions, such as inflammation, immunity, and neurotransmission. Dysregulation of phospholipase activity can contribute to the development of various diseases, including cancer, cardiovascular disease, and neurological disorders.

Dietary fats, also known as fatty acids, are a major nutrient that the body needs for energy and various functions. They are an essential component of cell membranes and hormones, and they help the body absorb certain vitamins. There are several types of dietary fats:

1. Saturated fats: These are typically solid at room temperature and are found in animal products such as meat, butter, and cheese, as well as tropical oils like coconut and palm oil. Consuming a high amount of saturated fats can raise levels of unhealthy LDL cholesterol and increase the risk of heart disease.
2. Unsaturated fats: These are typically liquid at room temperature and can be further divided into monounsaturated and polyunsaturated fats. Monounsaturated fats, found in foods such as olive oil, avocados, and nuts, can help lower levels of unhealthy LDL cholesterol while maintaining levels of healthy HDL cholesterol. Polyunsaturated fats, found in foods such as fatty fish, flaxseeds, and walnuts, have similar effects on cholesterol levels and also provide essential omega-3 and omega-6 fatty acids that the body cannot produce on its own.
3. Trans fats: These are unsaturated fats that have been chemically modified to be solid at room temperature. They are often found in processed foods such as baked goods, fried foods, and snack foods. Consuming trans fats can raise levels of unhealthy LDL cholesterol and lower levels of healthy HDL cholesterol, increasing the risk of heart disease.

It is recommended to limit intake of saturated and trans fats and to consume more unsaturated fats as part of a healthy diet.

Mersalyl is not a medical condition or diagnosis, but rather a pharmaceutical compound. It is a type of organic mercurial salt that was historically used in medicine as a diuretic and an antimicrobial agent. However, its use has been largely discontinued due to the toxic effects of mercury on the human body. Therefore, there isn't a medical definition for 'Mersalyl'.

Glycerides are esters formed from glycerol and one, two, or three fatty acids. They include monoglycerides (one fatty acid), diglycerides (two fatty acids), and triglycerides (three fatty acids). Triglycerides are the main constituents of natural fats and oils, and they are a major form of energy storage in animals and plants. High levels of triglycerides in the blood, also known as hypertriglyceridemia, can increase the risk of heart disease and stroke.

Cardiolipins are a type of phospholipid that are primarily found in the inner mitochondrial membrane of cells. They play a crucial role in several important cellular processes, including energy production, apoptosis (programmed cell death), and maintenance of the structural integrity of the mitochondria.

Cardiolipins are unique because they contain four fatty acid chains, whereas most other phospholipids contain only two. This gives cardiolipins a distinctive conical shape that is important for their function in maintaining the curvature and stability of the inner mitochondrial membrane.

Cardiolipins have also been implicated in various diseases, including neurodegenerative disorders, cancer, and bacterial infections. For example, changes in cardiolipin composition or distribution have been linked to mitochondrial dysfunction in Parkinson's disease and other neurological conditions. Additionally, certain bacteria, such as Neisseria gonorrhoeae and Chlamydia trachomatis, can manipulate host cell cardiolipins to facilitate their own survival and replication.

In summary, cardiolipins are essential phospholipids found in the inner mitochondrial membrane that play a critical role in several cellular processes, and have been implicated in various diseases.

Mitochondria in muscle, also known as the "powerhouses" of the cell, are organelles that play a crucial role in generating energy for muscle cells through a process called cellular respiration. They convert the chemical energy found in glucose and oxygen into ATP (adenosine triphosphate), which is the main source of energy used by cells.

Muscle cells contain a high number of mitochondria due to their high energy demands for muscle contraction and relaxation. The number and size of mitochondria in muscle fibers can vary depending on the type of muscle fiber, with slow-twitch, aerobic fibers having more numerous and larger mitochondria than fast-twitch, anaerobic fibers.

Mitochondrial dysfunction has been linked to various muscle disorders, including mitochondrial myopathies, which are characterized by muscle weakness, exercise intolerance, and other symptoms related to impaired energy production in the muscle cells.

Cholesteryl ester transfer proteins (CETP) are a group of plasma proteins that play a role in the transport and metabolism of lipids, particularly cholesteryl esters and triglycerides, between different lipoprotein particles in the bloodstream. These proteins facilitate the transfer of cholesteryl esters from high-density lipoproteins (HDL) to low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL), while simultaneously promoting the transfer of triglycerides in the opposite direction, from VLDL and LDL to HDL.

The net effect of CETP activity is a decrease in HDL cholesterol levels and an increase in LDL and VLDL cholesterol levels. This shift in lipoprotein composition can contribute to the development of atherosclerosis and cardiovascular disease, as lower HDL cholesterol levels and higher LDL cholesterol levels are associated with increased risk for these conditions.

Inhibition of CETP has been investigated as a potential strategy for increasing HDL cholesterol levels and reducing the risk of cardiovascular disease. However, clinical trials with CETP inhibitors have shown mixed results, and further research is needed to determine their safety and efficacy in preventing cardiovascular events.

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.

'Arachis hypogaea' is the scientific name for the peanut plant. It is a legume crop that grows underground, which is why it is also known as a groundnut. The peanut plant produces flowers above ground, and when the flowers are pollinated, the ovary of the flower elongates and grows downwards into the soil where the peanut eventually forms and matures.

The peanut is not only an important food crop worldwide but also has various industrial uses, including the production of biodiesel, plastics, and animal feed. The plant is native to South America and was domesticated by indigenous peoples in what is now Brazil and Peru thousands of years ago. Today, peanuts are grown in many countries around the world, with China, India, and the United States being the largest producers.

Intracellular membranes refer to the membrane structures that exist within a eukaryotic cell (excluding bacteria and archaea, which are prokaryotic and do not have intracellular membranes). These membranes compartmentalize the cell, creating distinct organelles or functional regions with specific roles in various cellular processes.

Major types of intracellular membranes include:

1. Nuclear membrane (nuclear envelope): A double-membraned structure that surrounds and protects the genetic material within the nucleus. It consists of an outer and inner membrane, perforated by nuclear pores that regulate the transport of molecules between the nucleus and cytoplasm.
2. Endoplasmic reticulum (ER): An extensive network of interconnected tubules and sacs that serve as a major site for protein folding, modification, and lipid synthesis. The ER has two types: rough ER (with ribosomes on its surface) and smooth ER (without ribosomes).
3. Golgi apparatus/Golgi complex: A series of stacked membrane-bound compartments that process, sort, and modify proteins and lipids before they are transported to their final destinations within the cell or secreted out of the cell.
4. Lysosomes: Membrane-bound organelles containing hydrolytic enzymes for breaking down various biomolecules (proteins, carbohydrates, lipids, and nucleic acids) in the process called autophagy or from outside the cell via endocytosis.
5. Peroxisomes: Single-membrane organelles involved in various metabolic processes, such as fatty acid oxidation and detoxification of harmful substances like hydrogen peroxide.
6. Vacuoles: Membrane-bound compartments that store and transport various molecules, including nutrients, waste products, and enzymes. Plant cells have a large central vacuole for maintaining turgor pressure and storing metabolites.
7. Mitochondria: Double-membraned organelles responsible for generating energy (ATP) through oxidative phosphorylation and other metabolic processes, such as the citric acid cycle and fatty acid synthesis.
8. Chloroplasts: Double-membraned organelles found in plant cells that convert light energy into chemical energy during photosynthesis, producing oxygen and organic compounds (glucose) from carbon dioxide and water.
9. Endoplasmic reticulum (ER): A network of interconnected membrane-bound tubules involved in protein folding, modification, and transport; it is divided into two types: rough ER (with ribosomes on the surface) and smooth ER (without ribosomes).
10. Nucleus: Double-membraned organelle containing genetic material (DNA) and associated proteins involved in replication, transcription, RNA processing, and DNA repair. The nuclear membrane separates the nucleoplasm from the cytoplasm and contains nuclear pores for transporting molecules between the two compartments.

Cyclohexanes are organic compounds that consist of a six-carbon ring arranged in a cyclic structure, with each carbon atom joined to two other carbon atoms by single bonds. This gives the molecule a shape that resembles a hexagonal ring. The carbons in the ring can be saturated, meaning that they are bonded to hydrogen atoms, or they can contain double bonds between some of the carbon atoms.

Cyclohexanes are important intermediates in the production of many industrial and consumer products, including plastics, fibers, dyes, and pharmaceuticals. They are also used as solvents and starting materials for the synthesis of other organic compounds.

One of the most well-known properties of cyclohexane is its ability to exist in two different conformations: a "chair" conformation and a "boat" conformation. In the chair conformation, the carbon atoms are arranged in such a way that they form a puckered ring, with each carbon atom bonded to two other carbons and two hydrogens. This conformation is more stable than the boat conformation, in which the carbon atoms form a flattened, saddle-shaped ring.

Cyclohexanes are relatively nonpolar and have low water solubility, making them useful as solvents for nonpolar substances. They also have a relatively high boiling point compared to other hydrocarbons of similar molecular weight, due to the fact that they can form weak intermolecular forces called London dispersion forces.

Cyclohexane is a flammable liquid with a mild, sweet odor. It is classified as a hazardous substance and should be handled with care. Exposure to cyclohexane can cause irritation of the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects, including neurological damage.

Acetyl-CoA C-acetyltransferase (also known as acetoacetyl-CoA thiolase or just thiolase) is an enzyme involved in the metabolism of fatty acids and ketone bodies. Specifically, it catalyzes the reaction that converts two molecules of acetyl-CoA into acetoacetyl-CoA, which is a key step in the breakdown of fatty acids through beta-oxidation.

The enzyme works by bringing together two acetyl-CoA molecules and removing a coenzyme A (CoA) group from one of them, forming a carbon-carbon bond between the two molecules to create acetoacetyl-CoA. This reaction is reversible, meaning that the enzyme can also catalyze the breakdown of acetoacetyl-CoA into two molecules of acetyl-CoA.

There are several different isoforms of Acetyl-CoA C-acetyltransferase found in various tissues throughout the body, with differing roles and regulation. For example, one isoform is highly expressed in the liver and plays a key role in ketone body metabolism, while another isoform is found in mitochondria and is involved in fatty acid synthesis.

Hydroxybutyrates are compounds that contain a hydroxyl group (-OH) and a butyric acid group. More specifically, in the context of clinical medicine and biochemistry, β-hydroxybutyrate (BHB) is often referred to as a "ketone body."

Ketone bodies are produced by the liver during periods of low carbohydrate availability, such as during fasting, starvation, or a high-fat, low-carbohydrate diet. BHB is one of three major ketone bodies, along with acetoacetate and acetone. These molecules serve as alternative energy sources for the brain and other tissues when glucose levels are low.

In some pathological states, such as diabetic ketoacidosis, the body produces excessive amounts of ketone bodies, leading to a life-threatening metabolic acidosis. Elevated levels of BHB can also be found in other conditions like alcoholism, severe illnesses, and high-fat diets.

It is important to note that while BHB is a hydroxybutyrate, not all hydroxybutyrates are ketone bodies. The term "hydroxybutyrates" can refer to any compound containing both a hydroxyl group (-OH) and a butyric acid group.

Multienzyme complexes are specialized protein structures that consist of multiple enzymes closely associated or bound together, often with other cofactors and regulatory subunits. These complexes facilitate the sequential transfer of substrates along a series of enzymatic reactions, also known as a metabolic pathway. By keeping the enzymes in close proximity, multienzyme complexes enhance reaction efficiency, improve substrate specificity, and maintain proper stoichiometry between different enzymes involved in the pathway. Examples of multienzyme complexes include the pyruvate dehydrogenase complex, the citrate synthase complex, and the fatty acid synthetase complex.

Detergents are cleaning agents that are often used to remove dirt, grease, and stains from various surfaces. They contain one or more surfactants, which are compounds that lower the surface tension between two substances, such as water and oil, allowing them to mix more easily. This makes it possible for detergents to lift and suspend dirt particles in water so they can be rinsed away.

Detergents may also contain other ingredients, such as builders, which help to enhance the cleaning power of the surfactants by softening hard water or removing mineral deposits. Some detergents may also include fragrances, colorants, and other additives to improve their appearance or performance.

In a medical context, detergents are sometimes used as disinfectants or antiseptics, as they can help to kill bacteria, viruses, and other microorganisms on surfaces. However, it is important to note that not all detergents are effective against all types of microorganisms, and some may even be toxic or harmful if used improperly.

It is always important to follow the manufacturer's instructions when using any cleaning product, including detergents, to ensure that they are used safely and effectively.

Cricetinae is a subfamily of rodents that includes hamsters, gerbils, and relatives. These small mammals are characterized by having short limbs, compact bodies, and cheek pouches for storing food. They are native to various parts of the world, particularly in Europe, Asia, and Africa. Some species are popular pets due to their small size, easy care, and friendly nature. In a medical context, understanding the biology and behavior of Cricetinae species can be important for individuals who keep them as pets or for researchers studying their physiology.

A muscle is a soft tissue in our body that contracts to produce force and motion. It is composed mainly of specialized cells called muscle fibers, which are bound together by connective tissue. There are three types of muscles: skeletal (voluntary), smooth (involuntary), and cardiac. Skeletal muscles attach to bones and help in movement, while smooth muscles are found within the walls of organs and blood vessels, helping with functions like digestion and circulation. Cardiac muscle is the specific type that makes up the heart, allowing it to pump blood throughout the body.

Polyethylene glycols (PEGs) are a family of synthetic, water-soluble polymers with a wide range of molecular weights. They are commonly used in the medical field as excipients in pharmaceutical formulations due to their ability to improve drug solubility, stability, and bioavailability. PEGs can also be used as laxatives to treat constipation or as bowel cleansing agents prior to colonoscopy examinations. Additionally, some PEG-conjugated drugs have been developed for use in targeted cancer therapies.

In a medical context, PEGs are often referred to by their average molecular weight, such as PEG 300, PEG 400, PEG 1500, and so on. Higher molecular weight PEGs tend to be more viscous and have longer-lasting effects in the body.

It's worth noting that while PEGs are generally considered safe for use in medical applications, some people may experience allergic reactions or hypersensitivity to these compounds. Prolonged exposure to high molecular weight PEGs has also been linked to potential adverse effects, such as decreased fertility and developmental toxicity in animal studies. However, more research is needed to fully understand the long-term safety of PEGs in humans.

Plasmalogens are a type of complex lipid called glycerophospholipids, which are essential components of cell membranes. They are characterized by having a unique chemical structure that includes a vinyl ether bond at the sn-1 position of the glycerol backbone and an ester bond at the sn-2 position, with the majority of them containing polyunsaturated fatty acids. The headgroup attached to the sn-3 position is typically choline or ethanolamine.

Plasmalogens are abundant in certain tissues, such as the brain, heart, and skeletal muscle. They have been suggested to play important roles in cellular functions, including membrane fluidity, signal transduction, and protection against oxidative stress. Reduced levels of plasmalogens have been associated with various diseases, including neurological disorders, cardiovascular diseases, and aging-related conditions.

"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.

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.

Tritium is not a medical term, but it is a term used in the field of nuclear physics and chemistry. Tritium (symbol: T or 3H) is a radioactive isotope of hydrogen with two neutrons and one proton in its nucleus. It is also known as heavy hydrogen or superheavy hydrogen.

Tritium has a half-life of about 12.3 years, which means that it decays by emitting a low-energy beta particle (an electron) to become helium-3. Due to its radioactive nature and relatively short half-life, tritium is used in various applications, including nuclear weapons, fusion reactors, luminous paints, and medical research.

In the context of medicine, tritium may be used as a radioactive tracer in some scientific studies or medical research, but it is not a term commonly used to describe a medical condition or treatment.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Dietary cholesterol is a type of cholesterol that comes from the foods we eat. It is present in animal-derived products such as meat, poultry, dairy products, and eggs. While dietary cholesterol can contribute to an increase in blood cholesterol levels for some people, it's important to note that saturated and trans fats have a more significant impact on blood cholesterol levels than dietary cholesterol itself.

The American Heart Association recommends limiting dietary cholesterol intake to less than 300 milligrams per day for most people, and less than 200 milligrams per day for those with a history of heart disease or high cholesterol levels. However, individual responses to dietary cholesterol can vary, so it's essential to monitor blood cholesterol levels and adjust dietary habits accordingly.

VLDL (Very Low-Density Lipoproteins) are a type of lipoprotein that play a crucial role in the transport and metabolism of fat molecules, known as triglycerides, in the body. They are produced by the liver and consist of a core of triglycerides surrounded by a shell of proteins called apolipoproteins, phospholipids, and cholesterol.

VLDL particles are responsible for delivering fat molecules from the liver to peripheral tissues throughout the body, where they can be used as an energy source or stored for later use. During this process, VLDL particles lose triglycerides and acquire more cholesterol, transforming into intermediate-density lipoproteins (IDL) and eventually low-density lipoproteins (LDL), which are also known as "bad" cholesterol.

Elevated levels of VLDL in the blood can contribute to the development of cardiovascular disease due to their association with increased levels of triglycerides and LDL cholesterol, as well as decreased levels of high-density lipoproteins (HDL), which are considered "good" cholesterol.

"Mortierella" is a genus of fungi that belongs to the family Mortierellaceae. These fungi are widely distributed in various environments, including soil, decaying plant material, and animal manure. Some species of Mortierella are known to produce enzymes that can break down complex organic compounds, making them useful in industrial applications such as bioremediation and the production of biofuels.

In a medical context, some species of Mortierella have been reported to cause rare but serious infections in humans, particularly in immunocompromised individuals. These infections typically involve the skin, soft tissues, or lungs and can be difficult to diagnose and treat due to their rarity and non-specific symptoms.

It's worth noting that Mortierella infections are not common, and most people come into contact with these fungi without experiencing any negative health effects. However, if you suspect that you may have a Mortierella infection or any other type of fungal infection, it's important to seek medical attention promptly.

A diet, in medical terms, refers to the planned and regular consumption of food and drinks. It is a balanced selection of nutrient-rich foods that an individual eats on a daily or periodic basis to meet their energy needs and maintain good health. A well-balanced diet typically includes a variety of fruits, vegetables, whole grains, lean proteins, and low-fat dairy products.

A diet may also be prescribed for therapeutic purposes, such as in the management of certain medical conditions like diabetes, hypertension, or obesity. In these cases, a healthcare professional may recommend specific restrictions or modifications to an individual's regular diet to help manage their condition and improve their overall health.

It is important to note that a healthy and balanced diet should be tailored to an individual's age, gender, body size, activity level, and any underlying medical conditions. Consulting with a healthcare professional, such as a registered dietitian or nutritionist, can help ensure that an individual's dietary needs are being met in a safe and effective way.

Sterols are a type of organic compound that is derived from steroids and found in the cell membranes of organisms. In animals, including humans, cholesterol is the most well-known sterol. Sterols help to maintain the structural integrity and fluidity of cell membranes, and they also play important roles as precursors for the synthesis of various hormones and other signaling molecules. Phytosterols are plant sterols that have been shown to have cholesterol-lowering effects in humans when consumed in sufficient amounts.

Chondrodysplasia punctata, rhizomelic is a rare genetic disorder that affects the development of bones and cartilage. The condition is characterized by shortened limbs (rhizomelia), particularly the upper arms and thighs, and multiple small punctate calcifications in the cartilage of the body, including the ears, nose, and other areas.

The disorder is caused by mutations in the gene PEX7, which is involved in the transport of enzymes to peroxisomes, cellular organelles that break down fatty acids and other substances. Without functional PEX7, these enzymes cannot reach the peroxisomes, leading to abnormal accumulation of lipids and other substances in various tissues, including bone and cartilage.

Chondrodysplasia punctata, rhizomelic is typically diagnosed in infancy or early childhood based on clinical features and imaging studies. The condition can be associated with a range of complications, including developmental delays, respiratory problems, hearing loss, and visual impairment. There is no cure for the disorder, and treatment is focused on managing symptoms and addressing specific complications as they arise.

Acyl-CoA dehydrogenase is a group of enzymes that play a crucial role in the body's energy production process. Specifically, they are involved in the breakdown of fatty acids within the cells.

More technically, acyl-CoA dehydrogenases catalyze the removal of electrons from the thiol group of acyl-CoAs, forming a trans-double bond and generating FADH2. This reaction is the first step in each cycle of fatty acid beta-oxidation, which occurs in the mitochondria of cells.

There are several different types of acyl-CoA dehydrogenases, each specific to breaking down different lengths of fatty acids. For example, very long-chain acyl-CoA dehydrogenase (VLCAD) is responsible for breaking down longer chain fatty acids, while medium-chain acyl-CoA dehydrogenase (MCAD) breaks down medium-length chains.

Deficiencies in these enzymes can lead to various metabolic disorders, such as MCAD deficiency or LC-FAOD (long-chain fatty acid oxidation disorders), which can cause symptoms like vomiting, lethargy, and muscle weakness, especially during periods of fasting or illness.

Deoxycholic acid is a bile acid, which is a natural molecule produced in the liver and released into the intestine to aid in the digestion of fats. It is also a secondary bile acid, meaning that it is formed from the metabolism of primary bile acids by bacteria in the gut.

Deoxycholic acid has a chemical formula of C~24~H~39~NO~4~ and a molecular weight of 391.57 g/mol. It is a white crystalline powder that is soluble in water and alcohol. In the body, deoxycholic acid acts as a detergent to help break down dietary fats into smaller droplets, which can then be absorbed by the intestines.

In addition to its role in digestion, deoxycholic acid has been investigated for its potential therapeutic uses. For example, it is approved by the US Food and Drug Administration (FDA) as an injectable treatment for reducing fat in the submental area (the region below the chin), under the brand name Kybella. When injected into this area, deoxycholic acid causes the destruction of fat cells, which are then naturally eliminated from the body over time.

It's important to note that while deoxycholic acid is a natural component of the human body, its therapeutic use can have potential side effects and risks, so it should only be used under the supervision of a qualified healthcare professional.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

PDOC00402 - Acyltransferases ChoActase / COT / CPT family in PROSITE Choline/Carnitine o-acyltransferase family[permanent dead ... A related transferase is carnitine acyltransferase. Palmitoylcarnitine Palmitoyl CoA There are four different forms of CPT in ... Carnitine O-palmitoyltransferase (also called carnitine palmitoyltransferase) is a mitochondrial transferase enzyme (EC 2.3. ... humans: CPT1A - associated with Carnitine palmitoyltransferase I deficiency CPT1B CPT1C CPT2 - associated with carnitine ...
van der Leij FR, Huijkman NC, Boomsma C, Kuipers JR, Bartelds B (2000). "Genomics of the human carnitine acyltransferase genes ... Carnitine O-palmitoyltransferase 2, mitochondrial is an enzyme that in humans is encoded by the CPT2 gene. Carnitine ... CPT2 together with carnitine palmitoyltransferase I oxidizes long-chain fatty acids in the mitochondria. Defects in this gene ... Verderio E, Cavadini P, Montermini L, Wang H, Lamantea E, Finocchiaro G, DiDonato S, Gellera C, Taroni F (1995). "Carnitine ...
... (CPT1) also known as carnitine acyltransferase I, CPTI, CAT1, CoA:carnitine acyl transferase ( ... It is part of a family of enzymes called carnitine acyltransferases. This "preparation" allows for subsequent movement of the ... van der Leij FR, Huijkman NC, Boomsma C, Kuipers JR, Bartelds B (2000). "Genomics of the human carnitine acyltransferase genes ... Carnitine palmitoyltransferase I is the first component and rate-limiting step of the carnitine palmitoyltransferase system, ...
Other names in common use include medium-chain/long-chain carnitine acyltransferase, carnitine medium-chain acyltransferase, ... Farrell, S. O.; Fiol, C. J.; Reddy, J. K.; Bieber, L. L. (1984-11-10). "Properties of purified carnitine acyltransferases of ... In the absence of carnitine acetyltransferase (CRAT), acyltransferases such as CROT can catalyze the acetyl group transfer from ... The significant catalytic residue within all carnitine acyltransferases, including CROT, has been found to be a histidine ...
Cronin CN (Sep 1997). "The conserved serine-threonine-serine motif of the carnitine acyltransferases is involved in carnitine ... carnitine acetyl coenzyme A transferase, carnitine acetylase, carnitine acetyltransferase, carnitine-acetyl-CoA transferase, ... "Carnitine acyltransferase enzymic catalysis requires a positive charge on the carnitine cofactor". Archives of Biochemistry and ... Jogl G, Hsiao YS, Tong L (Nov 2004). "Structure and function of carnitine acyltransferases". Annals of the New York Academy of ...
CPT II shares structural elements with other members of the carnitine acyltransferase protein family. The crystal structure of ... Carnitine O-palmitoyltransferase Carnitine palmitoyltransferase I deficiency Fasciculation Myokymia Primary carnitine ... 1993). "Comparison of the active sites of the purified carnitine acyltransferases from peroxisomes and mitochondria by using a ... The "carnitine shuttle" is composed of three enzymes that utilize carnitine to facilitate the import of hydrophobic long-chain ...
Carnitine octanoyltransferase (EC 2.3.1.137) is a carnitine acyltransferase that catalyzes the reversible transfer of fatty ... 2000). "Genomics of the human carnitine acyltransferase genes". Mol. Genet. Metab. 71 (1-2): 139-53. doi:10.1006/mgme.2000.3055 ... 2000) reviewed the function, structural features, and phylogenetics of human carnitine acyltransferase genes, including CROT.[ ... 2002). "Structural model of a malonyl-CoA-binding site of carnitine octanoyltransferase and carnitine palmitoyltransferase I: ...
This reaction takes place in the mitochondrial matrix and is catalyzed by carnitine acyltransferase 2 (also called carnitine ... L-Carnitine, acetyl-l-carnitine, and propionyl-l-carnitine are available in dietary supplement pills or powders, with a daily ... Carnitine exists as one of two stereoisomers (the two enantiomers d-carnitine (S-(+)-) and l-carnitine (R-(−)-)). Both are ... Two types of carnitine deficiency states exist. Primary carnitine deficiency is a genetic disorder of the cellular carnitine- ...
There carnitine acyltransferase II reverses the process, producing fatty acyl-CoA and carnitine. This shuttle mechanism is ... They are converted to fatty acyl carnitine by carnitine acyltransferase I, an enzyme of the inner leaflet of the outer ... Fatty acyl carnitine is then transported by an antiport in exchange for free carnitine to the inner surface of the inner ...
... carnitine palmitoyltransferase and glycerophosphate acyltransferase compared to peroxisomal β-oxidation and palmitoyl-CoA ...
... carnitine acyltransferase, AMP-activated protein kinase, and others. These enzymes are important targets for drug discovery ...
... but not as a protease or a carnitine acyltransferase". Archives of Biochemistry and Biophysics. 323 (2): 397-403. doi:10.1006/ ...
... inhibits fatty acids from associating with carnitine by regulating the enzyme carnitine acyltransferase, thereby ...
The liberated carnitine returns to the cytosol. It is important to note that carnitine acyltransferase I undergoes allosteric ... This occurs via a series of similar steps: Acyl CoA is conjugated to carnitine by carnitine acyltransferase I ( ... is converted to acyl CoA by carnitine acyltransferase (palmitoyltransferase) II located on the inner mitochondrial membrane. ... I located on the outer mitochondrial membrane Acyl carnitine is shuttled inside by a translocase Acyl carnitine (such as ...
... carnitine and carnitine acyltransferase I and II, reducing their bioavailability and consequently inhibiting beta oxidation of ...
... new fatty acids and can inhibit the transfer of the fatty acyl group from acyl CoA to carnitine with carnitine acyltransferase ...
Family 4.C.2 The Carnitine O-Acyl Transferase (CrAT) Family 4.C.3 The Acyl-CoA Thioesterase (AcoT) Family 4.D.1 The Putative ... Family 2.A.14 Lactate Permease Family 2.A.15 The Betaine/Carnitine/Choline Transporter (BCCT) Family 2.A.16 Tellurite- ...
... diacylglycerol O-acyltransferase EC 2.3.1.21: carnitine O-palmitoyltransferase EC 2.3.1.22: 2-acylglycerol O-acyltransferase EC ... phosphatidylcholine-retinol O-acyltransferase EC 2.3.1.136: polysialic-acid O-acetyltransferase EC 2.3.1.137: carnitine O- ... dolichol O-acyltransferase EC 2.3.1.124: Already listed as EC 2.3.1.20 EC 2.3.1.125: 1-alkyl-2-acetylglycerol O-acyltransferase ... sphingosine N-acyltransferase EC 2.3.1.25: plasmalogen synthase EC 2.3.1.26: sterol O-acyltransferase EC 2.3.1.27: cortisol O- ...
... carnitine acyltransferases MeSH D08.811.913.050.350.170 - carnitine O-acetyltransferase MeSH D08.811.913.050.350.200 - ... diacylglycerol o-acyltransferase MeSH D08.811.913.050.425 - glycerol-3-phosphate O-acyltransferase MeSH D08.811.913.050.600 - ... phosphatidylcholine-sterol O-acyltransferase MeSH D08.811.913.050.646 - retinol O-fatty-acyltransferase MeSH D08.811.913.050. ... 1-acylglycerol-3-phosphate O-acyltransferase MeSH D08.811.913.050.175 - 1-acylglycerophosphocholine O-acyltransferase MeSH ...
Glycine-N-acyltransferase GLYATL2 encoding protein Glycine-N-acyltransferase like 2 GPHA2: Glycoprotein hormone alpha-2 GYLTL1B ... carnitine palmitoyltransferase 1A (liver) CREBZF encoding protein CREB/ATF bZIP transcription factor DAK: Triokinase/FMN ... monoacylglycerol O-acyltransferase 2 MTRNR2L8: encoding protein MT-RNR2-like 8 NADSYN1: NAD synthetase 1 NAP1L4: nucleosome ... DGAT2 encoding protein Diacylglycerol O-acyltransferase 2 DHCR7: 7-dehydrocholesterol reductase DKK3: Dickkopf-related protein ...
"Downregulation of carnitine acyltransferases and organic cation transporter OCTN2 in mononuclear cells in healthy elderly and ... an organic cation/carnitine transporter, lead to deficient cellular carnitine uptake in primary carnitine deficiency". Human ... characterized by impaired carnitine transport, urinary carnitine wasting, low serum carnitine levels, reduced intracellular ... "Primary systemic carnitine deficiency is caused by mutations in a gene encoding sodium ion-dependent carnitine transporter". ...
β-oxidation in the peroxisome requires the use of a peroxisomal carnitine acyltransferase (instead of carnitine acyltransferase ... Acyl-carnitine is shuttled inside by a carnitine-acylcarnitine translocase, as a carnitine is shuttled outside. Acyl-carnitine ... The liberated carnitine is shuttled back to the cytosol, as an acyl-carnitine is shuttled into the matrix. If the fatty acyl- ... Acyl-CoA is transferred to the hydroxyl group of carnitine by carnitine palmitoyltransferase I, located on the cytosolic faces ...
However, no formal assessment of the utility of carnitine and arginine supplementation has been published, and its uses have ... Neuwald AF (August 1997). "Barth syndrome may be due to an acyltransferase deficiency". Current Biology. 7 (8): R465-6. doi: ... Metabolic deficiencies have been treated by oral arginine and carnitine supplementation, which has been shown to ameliorate ... CL remodeling in mammals requires additional enzymes, such as monolysocardiolipin acyltransferase (MLCLAT), acyl-CoA: ...
SLC22A3 is an extraneuronal monoamine transporter that is present in astrocytes, and SLC22A5 is a high-affinity carnitine ... CYP2D6, dopamine β-hydroxylase, flavin-containing monooxygenase 3, butyrate-CoA ligase, and glycine N-acyltransferase are the ... cite encyclopedia}}: ,work= ignored (help) "Substrate/Product". glycine N-acyltransferase. Archived from the original on 23 ...
... : diacylglycerol acyltransferase (DGAT) plays an important role in energy metabolism on account of key enzyme in ... Transport of acyl-CoA into the mitochondria requires carnitine palmitoyltransferase 1 (CPT1), which converts acyl-CoA into ... Yu, Yi‐Hao; Ginsberg, Henry (8 July 2009). "The role of acyl‐CoA:diacylglycerol acyltransferase (DGAT) in energy metabolism". ...
Lysophosphatidylcholine acyltransferase 1 LYRM7: encoding protein LYR motif containing 7 LYSMD3: LysM and putative ... carboxylase deficiency Myelodysplastic syndrome Netherton syndrome Nicotine dependency Parkinson's disease Primary carnitine ...
Chen S, Ogawa A, Ohneda M, Unger RH, Foster DW, McGarry JD (July 1994). "More direct evidence for a malonyl-CoA-carnitine ... It works by inhibiting the enzyme Carnityl Acyl Transferase I (CAT-I) indirectly which is present in the mitochondria. This ... Lehtihet M, Welsh N, Berggren PO, Cook GA, Sjoholm A (August 2003). "Glibenclamide inhibits islet carnitine ...
... carnitine dehydratase - carrier - carveol dehydrogenase - CAT assay - CAT RNA-binding domain - catalase-related immune- ... palmitoyl acyltransferase - Parkinson's disease - pBR322 - PCR - pedigree - peptide - peptide-transporting ATPase - peptide ... phospholipid acyltransferase - phosphonate-transporting ATPase - phosphorylation - physical map - plant calmodulin-binding ...
Acyl-carnitine is shuttled inside by a carnitine-acylcarnitine translocase, as a carnitine is shuttled outside. Acyl-carnitine ... Enzymes, acyltransferases and transacylases, incorporate fatty acids in phospholipids, triacylglycerols, etc. by transferring ... Acyl-CoA is transferred to the hydroxyl group of carnitine by carnitine palmitoyltransferase I, located on the cytosolic faces ... The liberated carnitine is shuttled back to the cytosol, as an acyl-CoA is shuttled into the mitochondrial matrix. Beta ...
Rytting E, Audus KL (January 2005). "Novel organic cation transporter 2-mediated carnitine uptake in placental choriocarcinoma ... and glycine N-acyltransferase (GLYAT) are the enzymes known to metabolize amphetamine or its metabolites in humans. Amphetamine ... and SLC22A5 is a high-affinity carnitine transporter. Amphetamine is known to strongly induce cocaine- and amphetamine- ... the role of glycine N-acyltransferase, and factors that influence interindividual variation". Expert Opinion on Drug Metabolism ...
  • Hepatic steatosis, inflammatory cell infiltration, and hepatocyte ballooning in the liver and increased hepatic mRNA expression of fatty acid synthase and glycerol-3-phosphate acyltransferase were observed in the MSG-treated mice. (biomedcentral.com)
  • Gerbling, H., Gerhardt, B. (1988) Carnitine acyltransferase activity of mitochondria from mung bean hypocotyls. (springer.com)
  • Carnitine acyltransferase (CAT) transports free fatty acids into the mitochondria and therefore regulates their entry into the oxidative pathway. (medscape.com)
  • Acylcarnitines are formed in the mitochondria by esterification between carnitine and acyl-CoAs. (bvsalud.org)
  • Carnitine palmitoyltransferase 1 (CPT1) is the enzyme in the outer mitochondrial membrane that converts long-chain acyl-CoA species to their corresponding long-chain acyl-carnitines for transport into the mitochondria (see Fig. Long‐Term Follow‐Up of Bezafibrate Treatment in Patients With the Myopathic Form of Carnitine Palmitoyltransferase 2 Deficiency. (siderac.com)
  • Palmitoylcarnitine Palmitoyl CoA There are four different forms of CPT in humans: CPT1A - associated with Carnitine palmitoyltransferase I deficiency CPT1B CPT1C CPT2 - associated with carnitine palmitoyltransferase II deficiency Fatty acid degradation § Transport into the mitochondrial matrix Jogl G, Tong L (January 2003). (wikipedia.org)
  • Dysfunction of this process leads to the genetic disorders primary carnitine deficiency , carnitine palmitoyltransferase I deficiency , carnitine palmitoyltransferase II deficiency and carnitine-acylcarnitine translocase deficiency . (wikidoc.org)
  • Carnitine palmitoyltransferase II deficiency is an inherited disorder of mitochondrial long-chain fatty acid oxidation. (siderac.com)
  • Carnitine O-palmitoyltransferase (also called carnitine palmitoyltransferase) is a mitochondrial transferase enzyme (EC 2.3.1.21) involved in the metabolism of palmitoylcarnitine into palmitoyl-CoA. (wikipedia.org)
  • miR-370 targets the 3' untranslated region (UTR) of Cpt1alpha, and it downregulated the expression of the carnitine palmitoyl transferase 1alpha (Cpt1alpha) gene as well as the rate of beta oxidation. (nih.gov)
  • A related transferase is carnitine acyltransferase. (wikipedia.org)
  • CPT-2 deficiency occurs when an enzyme, called carnitine palmitoyl transferase - type 2 (CPT-2… Carnitine palmitoyltransferase 2 (CPT-2 or CPT-II) is one of a family of carnitine acyltransferases in humans that catalyze the reversible transfer of acyl groups between coenzyme A (CoASH) and L-carnitine, converting fatty acyl-CoA esters into fatty acyl-carnitine esters. (siderac.com)
  • Carnitine palmitoyl transferase II deficiency, myopathic form Disease definition The myopathic form of carnitine palmitoyltransferase II (CPT II) deficiency, an inherited metabolic disorder that affects mitochondrial oxidation of long chain fatty acids (LCFA), is the most common and the least severe form of CPT II deficiency (see this term). (siderac.com)
  • The highest concentrations of carnitine are found in red meat and dairy products. (wikidoc.org)
  • High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and next-generation sequencing (NGS) were used to detect the concentrations of carnitine in the blood spots and for diagnosis. (bvsalud.org)
  • acyltransferase transferring other than amino-acyl group) inhibitor that interferes with the action of mitochondrial carnitine O -palmitoyltransferase (EC 2.3.1.21). (ebi.ac.uk)
  • Muscle weakness during prolonged exercise is an important characteristic of a deficiency of carnitine acyl transferases because muscle relies on fatty acids as a long-term source of energy. (desenzanoloft.it)
  • Carnitine palmitoyltransferase 2 (CPT2) deficiency: This rare genetic condition prevents the body from using certain fats for energy. (siderac.com)
  • A novel mutation leading to the lethal form of carnitine palmitoyltransferase type-2 deficiency. (siderac.com)
  • Carnitine palmitoyltransferase (CPT) deficiency is a group of disorders caused by defects in the enzymes CPT I or II. (siderac.com)
  • Carnitine palmitoyltransferase 2 (CPT2) deficiency is a condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). (siderac.com)
  • Carnitine palmitoyltransferase 1A (CPT1A) deficiency is a disorder of fatty acid oxidation, the process by which the body breaks down fatty acids from food for energy. (siderac.com)
  • Carnitine transports long-chain acyl groups from fatty acids into the mitochondrial matrix , so that they can be broken down through beta-oxidation to acetate to obtain usable energy via the citric acid cycle . (wikidoc.org)
  • Carnitine acyltransferase I undergoes allosteric inhibition as a result of malonyl-CoA , an intermediate in fatty acid biosynthesis, in order to prevent futile cycling between beta-oxidation and fatty acid synthesis. (wikidoc.org)
  • Cell Rep. … Once in the matrix, carnitine palmitoyltransferase II (CPT-II) hydrolyses the acyl-carnitine to free carnitine and LC-CoA, for beta-oxidation. (siderac.com)
  • The role of carnitine acyltransferase (CAT) in control of hepatic lipid metabolism in developing small-for-estational-age piglets. (ncsu.edu)
  • L-carnitine has indispensable functions in intermediary metabolism and is received by endogenous synthesis and from exogenous sources. (poultryworld.net)
  • It plays an obligate role in fatty acid metabolism by directing fatty acids into the mitochondrial oxidative pathway through the action of specialised acyltransferases. (poultryworld.net)
  • The importance of this compound and of the carnitine shuttle in eukaryotic energy metabolism has been highlighted by many studies linking diverse metabolic diseases to a dysfunction of carnitine related metabolism. (sasm.org.za)
  • Transfection of HepG2 cells with sense or antisense miR-370 or miR-122 upregulated and downregulated, respectively, the transcription factor sterol-regulatory element binding protein 1c (SREBP-1c) and the enzymes diacylglycerol acyltransferase-2 (DGAT2), fatty acid synthase (FAS), and acyl-CoA carboxylase 1 (ACC1) that regulate fatty acid and triglyceride biosynthesis. (nih.gov)
  • In Fischer 344 rats, feeding trans fat for 15 mo increased only moderately various enzymes of β-oxidation except for carnitine acyltransferase. (elsevierpure.com)
  • This study describes the cloning and expression of the four genes encoding the enzymes from the N. crassa carnitine biosynthesis pathway in S. cerevisiae . (sasm.org.za)
  • This function is supported by the activities of various carnitine acyl-transferases and transporters, whose activity is collectively referred to as the carnitine shuttle. (sasm.org.za)
  • The carnitine shuttle. (siderac.com)
  • Quantification of carnitine esters by high-performance liquid chromatography. (ncsu.edu)
  • The MCT feeding was associated with transient increases in plasma carnitine and carnitine esters, and feeding odd-chain MCT (tri-C5 or tri-C7) led to elevated levels of propionylcarnitine in plasma. (ncsu.edu)
  • To assess the effects of acylcarnitine accumulation on muscle insulin sensitivity, a model of muscle acylcarnitine accumulation was generated by deleting carnitine palmitoyltransferase 2 (CPT2) specifically from skeletal muscle (Cpt2 Sk−/− mice).CPT2 is an irreplaceable enzyme for mitochondrial long-chain fatty acid oxidation, converting matrix acylcarnitines to acyl-CoAs. (siderac.com)
  • Carnitine O-palmitoyltransferase 1, muscle isoform (EC: 2.3.1.21 Search proteins in UniProtKB for this EC number. (siderac.com)
  • These disorders are in many cases effectively treated through dietary carnitine supplementation. (sasm.org.za)
  • Supplementation studies have revealed that carnitine has a broad range of beneficial and potentially therapeutic effects. (sasm.org.za)
  • [2] Vitamin C ( ascorbic acid ) is essential to the synthesis of carnitine. (wikidoc.org)
  • The engineered yeast strains are able to catalyze the synthesis of L-carnitine from the pathway's precursor, trimethyllysine, as well as from intermediates. (sasm.org.za)
  • Yeast with the capacity to synthesise carnitine can provide an alternative to the existing industrial synthesis processes and also open additional doors to fermented or single cell protein products enriched with L-carnitine. (sasm.org.za)
  • Longer-term (24 and 48 h) treatment reduced the expression of lipogenic markers (FA synthase and sterol regulatory element-binding protein-1) and increased the expression of lipolytic [hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL)] and mitochondrial (peroxisome proliferator-activated receptor γ coactivator-1α and carnitine palmitoyltransferase 1) markers. (academic-accelerator.com)
  • It has been suggested that the L-carnitine requirement may be increased under certain circumstances such as via higher performance, various stress conditions and where the diet is deficient in animal protein sources. (poultryworld.net)
  • Decanoyl coenzyme A (Decanoyl CoA) is coupled with S-adenosylmethionine (SAM) by Vibrio cholera CqsA enzyme to produce a potent quorum-sensing molecule, 3-aminotridec-2-en-4-one (Ea-CAI-1. (sigmaaldrich.com)
  • Fatty acids must be activated before binding to the carnitine molecule to form acyl-carnitine . (wikidoc.org)
  • L-carnitine, a medically relevant, amino acid-derived molecule is a valuable target for biotechnological production. (sasm.org.za)
  • L-Carnitine is a vitamin-like molecule with GRASS (generally recognized as safe) status that plays an essential and conserved shuttling function in eukaryotes by transferring activated acyl residues across intracellular membranes. (sasm.org.za)
  • This occurs enzymatically via carnitine acyltransferases. (bvsalud.org)
  • The inhibition by malonyl-CoA is characteristic of carnitine palmitoyltransferase type 1, but not of type 2. (siderac.com)
  • The rate of mitochondrial ketogenesis and the activity of carnitine acyltransferase measured with trans-9-octadecenoic acid as a substrate were about half those with the cis-counterpart. (elsevierpure.com)
  • This was achieved by cloning and reconstructing the Neurospora crassa L-carnitine biosynthesis pathway in the baker's yeast to create an L-carnitine producing strain. (sasm.org.za)
  • The initial characterisation of the eukaryotic carnitine biosynthesis pathway was carried out in the fungus, Neurospora crassa , but the conserved enzymatic activities and most of the corresponding genes have now been characterised in various higher eukaryotes. (sasm.org.za)
  • The eukaryotic carnitine biosynthesis pathway catalyses the conversion of the pathway's precursor, trimthyllysine, through four hydroxylation and dehydrogenation reactions to form L-carnitine (Fig. 1). (sasm.org.za)
  • The data indicates that the entire pathway is functional in yeast and provides the first description of S. cerevisia e strains capable of synthesising L-carnitine from TML. (sasm.org.za)
  • The method proved to be sufficiently sensitive to determine changes in the carnitine ester profile in plasma resulting from metabolic disorders or metabolic insults. (ncsu.edu)
  • Carnitine is biosynthesized within the body from the amino acids lysine or methionine primarily in the liver and kidneys . (wikidoc.org)
  • It has been speculated that during growth or pregnancy the requirement of carnitine could exceed its natural production. (wikidoc.org)
  • Carnitine , also known as L -carnitine or levocarnitine , is a quaternary ammonium compound biosynthesized from the amino acids lysine and methionine . (wikidoc.org)
  • The concentration of L-carnitine in animals varies widely across species, tissue type, and nutritional status of the animal. (poultryworld.net)
  • Especially encouraging, was the modified strains ability to convert 58% of the intermediate gamma-butyrobetaїne to L-carnitine in laboratory conditions. (sasm.org.za)
  • The acyl group on CoA can now be transferred to carnitine and the resulting acyl-carnitine transported into the mitochondrial matrix . (wikidoc.org)
  • The wide range of genetic tools available for the introduction and heterologous expression of genes in this model organism provides an opportunity of genetically engineering a carnitine producing yeast with a variety of possible industrial applications. (sasm.org.za)
  • Products containing L-carnitine cannot be marketed as "natural health products" in Canada . (wikidoc.org)
  • L -Carnitine products and supplements are not allowed to be imported into Canada( Health Canada ). (wikidoc.org)
  • To cater for the growing L-carnitine market, current industrial processes are producing the compound from chemical industry waste products, such as D-carnitine, γ-butyrobetaїne and cronobetaїne, using whole cell biotransformations by Escherichia coli and Proteus spp. (sasm.org.za)
  • In poultry production, L-carnitine has a multi functional purpose, which includes: growth promotion, strengthening the immune system, antioxidant effects and improving semen quality. (poultryworld.net)
  • The mitochondrial membrane‐associated carnitine palmitoyltransferase system is a validated target for the treatment of type 2 diabetes mellitus. (siderac.com)
  • Carnitine was originally found as a growth factor for mealworms and labeled vitamin Bt . (wikidoc.org)