Citrulline is an α-amino acid, primarily produced in the urea cycle in the liver and found in some dietary proteins, which functions as a vital intermediator in the nitrogen metabolism and vasodilation, and can be supplemented for potential health benefits in improving blood flow, reducing fatigue, and enhancing exercise performance.
An amino acid produced in the urea cycle by the splitting off of urea from arginine.
An essential amino acid that is physiologically active in the L-form.
A plant genus of the family CUCURBITACEAE known for the edible fruit.
A urea cycle enzyme that catalyzes the formation of orthophosphate and L-citrulline (CITRULLINE) from CARBAMOYL PHOSPHATE and L-ornithine (ORNITHINE). Deficiency of this enzyme may be transmitted as an X-linked trait. EC 2.1.3.3.
Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
The monoanhydride of carbamic acid with PHOSPHORIC ACID. It is an important intermediate metabolite and is synthesized enzymatically by CARBAMYL-PHOSPHATE SYNTHASE (AMMONIA) and CARBAMOYL-PHOSPHATE SYNTHASE (GLUTAMINE-HYDROLYZING).
An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.
A group of diseases related to a deficiency of the enzyme ARGININOSUCCINATE SYNTHASE which causes an elevation of serum levels of CITRULLINE. In neonates, clinical manifestations include lethargy, hypotonia, and SEIZURES. Milder forms also occur. Childhood and adult forms may present with recurrent episodes of intermittent weakness, lethargy, ATAXIA, behavioral changes, and DYSARTHRIA. (From Menkes, Textbook of Child Neurology, 5th ed, p49)
An enzyme of the urea cycle which splits argininosuccinate to fumarate plus arginine. Its absence leads to the metabolic disease ARGININOSUCCINIC ACIDURIA in man. EC 4.3.2.1.
A ureahydrolase that catalyzes the hydrolysis of arginine or canavanine to yield L-ornithine (ORNITHINE) and urea. Deficiency of this enzyme causes HYPERARGININEMIA. EC 3.5.3.1.
A non-essential amino acid that is synthesized from GLUTAMIC ACID. It is an essential component of COLLAGEN and is important for proper functioning of joints and tendons.
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
This amino acid is formed during the urea cycle from citrulline, aspartate and ATP. This reaction is catalyzed by argininosuccinic acid synthetase.
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
A class of enzymes that catalyze oxidation-reduction reactions of amino acids.
A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.
An enzyme that catalyzes the formation of carbamoyl phosphate from ATP, carbon dioxide, and ammonia. This enzyme is specific for arginine biosynthesis or the urea cycle. Absence or lack of this enzyme may cause CARBAMOYL-PHOSPHATE SYNTHASE I DEFICIENCY DISEASE. EC 6.3.4.16.
A group of membrane transport proteins that transport biogenic amine derivatives of catechol across the PLASMA MEMBRANE. Catecholamine plasma membrane transporter proteins regulate neural transmission as well as catecholamine metabolism and recycling.
Congenital absence of or defects in structures of the mouth.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A malabsorption syndrome resulting from extensive operative resection of the SMALL INTESTINE, the absorptive region of the GASTROINTESTINAL TRACT.
Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.
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)
Absorptive cells in the lining of the INTESTINAL MUCOSA. They are differentiated EPITHELIAL CELLS with apical MICROVILLI facing the intestinal lumen. Enterocytes are more abundant in the SMALL INTESTINE than in the LARGE INTESTINE. Their microvilli greatly increase the luminal surface area of the cell by 14- to 40 fold.
Diamino acids are a type of modified amino acids containing two amino groups, which can be found in various biological molecules and play important roles in various cellular processes, such as nitrogen fixation and protein synthesis.
A group of inherited kidney disorders characterized by the abnormally elevated levels of AMINO ACIDS in URINE. Genetic mutations of transport proteins result in the defective reabsorption of free amino acids at the PROXIMAL RENAL TUBULES. Renal aminoaciduria are classified by the specific amino acid or acids involved.
A pyridoxal phosphate enzyme that catalyzes the formation of glutamate gamma-semialdehyde and an L-amino acid from L-ornithine and a 2-keto-acid. EC 2.6.1.13.
Amino acid transporter systems capable of transporting basic amino acids (AMINO ACIDS, BASIC).
An inherited urea cycle disorder associated with deficiency of the enzyme ORNITHINE CARBAMOYLTRANSFERASE, transmitted as an X-linked trait and featuring elevations of amino acids and ammonia in the serum. Clinical features, which are more prominent in males, include seizures, behavioral alterations, episodic vomiting, lethargy, and coma. (Menkes, Textbook of Child Neurology, 5th ed, pp49-50)
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
A natural product that has been considered as a growth factor for some insects.
Salts of nitrous acid or compounds containing the group NO2-. The inorganic nitrites of the type MNO2 (where M=metal) are all insoluble, except the alkali nitrites. The organic nitrites may be isomeric, but not identical with the corresponding nitro compounds. (Grant & Hackh's Chemical Dictionary, 5th ed)
Phenylbutyrates are a class of chemical compounds, specifically sodium phenylbutyrate and glycerol phenylbutyrate, used medically as a nitrogen-binding agent to reduce the concentration of ammonia in the blood, primarily used in the treatment of urea cycle disorders.
Orotic acid, also known as pyrophosphoric acid dihydrate, is a organic compound that plays a role in the biosynthesis of pyrimidines, and elevated levels of orotic acid in urine can indicate certain genetic disorders or liver dysfunction.

L-Ascorbic acid potentiates nitric oxide synthesis in endothelial cells. (1/917)

Ascorbic acid has been shown to enhance impaired endothelium-dependent vasodilation in patients with atherosclerosis by a mechanism that is thought to involve protection of nitric oxide (NO) from inactivation by free oxygen radicals. The present study in human endothelial cells from umbilical veins and coronary arteries investigates whether L-ascorbic acid additionally affects cellular NO synthesis. Endothelial cells were incubated for 24 h with 0.1-100 microM ascorbic acid and were subsequently stimulated for 15 min with ionomycin (2 microM) or thrombin (1 unit/ml) in the absence of extracellular ascorbate. Ascorbate pretreatment led to a 3-fold increase of the cellular production of NO measured as the formation of its co-product citrulline and as the accumulation of its effector molecule cGMP. The effect was saturated at 100 microM and followed a similar kinetics as seen for the uptake of ascorbate into the cells. The investigation of the precursor molecule L-gulonolactone and of different ascorbic acid derivatives suggests that the enediol structure of ascorbate is essential for its effect on NO synthesis. Ascorbic acid did not induce the expression of the NO synthase (NOS) protein nor enhance the uptake of the NOS substrate L-arginine into endothelial cells. The ascorbic acid effect was minimal when the citrulline formation was measured in cell lysates from ascorbate-pretreated cells in the presence of known cofactors for NOS activity. However, when the cofactor tetrahydrobiopterin was omitted from the assay, a similar potentiating effect of ascorbate pretreatment as seen in intact cells was demonstrated, suggesting that ascorbic acid may either enhance the availability of tetrahydrobiopterin or increase its affinity for the endothelial NOS. Our data suggest that intracellular ascorbic acid enhances NO synthesis in endothelial cells and that this may explain, in part, the beneficial vascular effects of ascorbic acid.  (+info)

Effect of ornithine and lactate on urea synthesis in isolated hepatocytes. (2/917)

1. In hepatocytes isolated from 24 h-starved rats, urea production from ammonia was stimulated by addition of lactate, in both the presence and the absence of ornithine. The relationship of lactate concentration to the rate of urea synthesis was hyperbolic. 2. Other glucose precursors also stimulated urea production to varying degrees, but none more than lactate. Added oleate and butyrate did not stimulate urea synthesis. 3. Citrulline accumulation was largely dependent on ornithine concentration. As ornithine was increased from 0 to 40 mM, the rate of citrulline accumulation increased hyperbolically, and was half-maximal when ornithine was 8-12 mM. 4. The rate of citrulline accumulation was independent of the presence of lactate, but with pyruvate the rate increased. 5. The rate of urea production continued to increase as ornithine was varied from 0 to 40 mM. 6. It was concluded that intermediates provided by both ornithine and lactate are limiting for urea production from ammonia in isolated liver cells. It was suggested that the stimulatory effect of lactate lies in increased availability of cytosolic aspartate for condensation with citrulline.  (+info)

Hepatocyte gene therapy in a large animal: a neonatal bovine model of citrullinemia. (3/917)

The development of gene-replacement therapy for inborn errors of metabolism has been hindered by the limited number of suitable large-animal models of these diseases and by inadequate methods of assessing the efficacy of treatment. Such methods should provide sensitive detection of expression in vivo and should be unaffected by concurrent pharmacologic and dietary regimens. We present the results of studies in a neonatal bovine model of citrullinemia, an inborn error of urea-cycle metabolism characterized by deficiency of argininosuccinate synthetase and consequent life-threatening hyperammonemia. Measurements of the flux of nitrogen from orally administered 15NH4 to [15N]urea were used to determine urea-cycle activity in vivo. In control animals, these isotopic measurements proved to be unaffected by pharmacologic treatments. Systemic administration of a first-generation E1-deleted adenoviral vector expressing human argininosuccinate synthetase resulted in transduction of hepatocytes and partial correction of the enzyme defect. The isotopic method showed significant restoration of urea synthesis. Moreover, the calves showed clinical improvement and normalization of plasma glutamine levels after treatment. The results show the clinical efficacy of treating a large-animal model of an inborn error of hepatocyte metabolism in conjunction with a method for sensitively measuring correction in vivo. These studies will be applicable to human trials of the treatment of this disorder and other related urea-cycle disorders.  (+info)

Arginine biosynthesis in Neisseria gonorrhoeae: enzymes catalyzing the formation of ornithine and citrulline. (4/917)

Many of the Neisseria gonorrhoeae strains isolated from patients require arginine for growth in a defined medium. As a basis for genetic studies of these Arg- strains, we examined two biosynthetic enzymes of Arg+ (nonrequiring) gonococci. Cell-free extracts contained (i) glutamate acetyltransferase, which catalyzes the formation of L-ornithine from alpha-N-acetyl-L-ornithine, and (ii) ornithine transcaramylase, which catalyzes the reaction between L-ornithine and carbamyl phosphate, yielding L-citrulline. Arg- strains were unable to utilze alpha-N-acetyl-L-ornithine for growth lacked significant activity of glutamate acetyltransferase, and activity was gained by Arg+ clones derived by DNA-mediated transformation. Some of the Arg- patient isolates were unable to use either alpha-N-acetyl-L-ornithine or L-ornithine in place of arginine, and two separate steps of genetic transformation were required to yield Arg+ cells. Extracts of these doubly auxotrophic cells lacked glutamate acetyltransferase activity, but, unexpectedly, they displayed normal ornithine transcarbamylase activity. This finding illustrates the importance of identifying the products specified by arg loci during genetic studies of arginine auxotrophy.  (+info)

Effects of ethanol on intraovarian nitric oxide production in the prepubertal rat. (5/917)

Nitric oxide (NO) has been shown to contribute to ovarian development and function. In non-ovarian tissues NO can be altered by ethanol (ETOH), a drug considered to be a gonadal toxin in men as well as male and female rats. The present study was undertaken to determine if some of the detrimental effects of chronic ETOH exposure on prepubertal ovarian function could be due to ETOH-induced alterations in the intraovarian NO system. Rats were implanted with intragastric cannulae on day 24 and began receiving control or ETOH diets on day 29. All rats were killed on day 34, determined to be in the late juvenile stage of development, and their ovaries and blood were collected. We analyzed the expression of the two constitutive forms of nitric oxide synthase (NOS), i.e. neuronal (n) NOS and endothelial (e) NOS, as well as the inducible (i) form of NOS protein in the ovaries of control and ETOH-treated rats by Western immunoblotting. Results demonstrate that eNOS protein increased markedly (P<0.02; 140 kDa) in ETOH-treated rats compared with controls. ETOH treatment did not alter the protein expression of nNOS (155 kDa) and only slightly increased that of iNOS (130 kDa). We also assessed NOS activity as determined by nitrite accumulation and by the conversion of L-[14C]arginine to L-[14C]citrulline. In this regard, the ETOH-treated animals showed an increase in ovarian nitrite generation (P<0.05), as well as an increase in ovarian citrulline formation (P<0.0001), when compared with control animals. Along with the above described ETOH-induced increases in ovarian eNOS and NO activity, the serum levels of estradiol were concomitantly suppressed (P<0.001) in the ETOH-treated rats. These results demonstrate for the first time the ETOH-induced changes in the prepubertal ovarian NO/NOS system, and suggest that these alterations contribute to the detrimental actions of the drug on prepubertal ovarian development and function.  (+info)

Cholinergic and GABAergic regulation of nitric oxide synthesis in the guinea pig ileum. (6/917)

Nitric oxide (NO) synthesis was examined in intact longitudinal muscle-myenteric plexus preparations of the guinea pig ileum by determining the formation of [3H]citrulline during incubation with [3H]arginine. Spontaneous [3H]citrulline production after 30 min was 80-90 dpm/mg, which constituted approximately 1% of the tissue radioactivity. Electrical stimulation (10 Hz) led to a threefold increase in [3H]citrulline formation. Removal of calcium from the medium or addition of NG-nitro-L-arginine strongly inhibited both spontaneous and electrically induced production of [3H]citrulline. TTX reduced the electrically induced but not spontaneous [3H]citrulline formation. The electrically induced formation of [3H]citrulline was diminished by (+)-tubocurarine and mecamylamine and enhanced by scopolamine, which suggests that endogenous ACh inhibits, via muscarinic receptors, and stimulates, via nicotinic receptors, the NO synthesis in the myenteric plexus. The GABAA receptor agonist muscimol and GABA also reduced the electrically evoked formation of [3H]citrulline, whereas baclofen was without effect. Bicuculline antagonized the inhibitory effect of GABA. It is concluded that nitrergic myenteric neurons are equipped with GABAA receptors, which mediate inhibition of NO synthesis.  (+info)

Nitric oxide production is reduced in patients with chronic renal failure. (7/917)

In patients with chronic renal failure (CRF), atherosclerosis is a major cause of cardiovascular morbidity and mortality. Generally, atherosclerosis has been associated with a reduced bioavailability of nitric oxide (NO). Experimental studies have indicated the presence of enhanced NO degradation by reactive oxygen species as well as decreased NO production as possible causes for this reduced NO bioavailability. So far, the question whether or not NO production is impaired in patients with CRF has never been investigated. Therefore, we measured whole body NO production in 7 patients with CRF, and in 7 matched healthy subjects. To assess the relative importance of a dysfunction of NO synthase (NOS), we compared the NO production of these patients to that of 2 other groups known to have endothelial dysfunction, ie, 7 patients with familial hypercholesterolemia (FH) who did not yet have signs of clinical cardiovascular disease (all nonsmokers), and 5 cigarette smokers. These groups were also compared with 7 nonsmoking, age-matched healthy subjects. Whole body NO production, determined as in vivo arginine-to-citrulline conversion, was assessed by giving an intravenous infusion of [15N2]-arginine as a substrate for NOS and measuring isotopic plasma enrichment of [15N]-citrulline by LC-MS. NO production in the CRF patients (0.13+/-0.02 micromol. kg-1. h-1) was significantly lower (P<0.05) than in the corresponding control group (0.23+/-0.09 micromol. kg-1. h-1). NO production also tended to be lower in the FH patients (0.16+/-0.04 micromol. kg-1. h-1), but the difference with the corresponding control group did not reach significance (0.22+/-0.06 micromol. kg-1. h-1). In the group of smokers, NO production was similar to that in nonsmokers (0. 22+/-0.09 micromol. kg-1. h-1). In conclusion, it is demonstrated for the first time that basal whole body NO production is reduced in patients with CRF. This finding implies that therapeutic interventions to endothelial dysfunction in these patients should be primarily directed toward improvement of NO production. The finding of only a tendency toward reduction of NO production in patients with FH and the absence of a reduction in cigarette smokers suggests that other mechanisms such as enhanced NO degradation may be involved in the decrease of NO bioavailability in these groups.  (+info)

Lactate inhibits citrulline and arginine synthesis from proline in pig enterocytes. (8/917)

Hypocitrullinemia and hypoargininemia but hyperprolinemia are associated with elevated plasma concentration of lactate in infants. Because the small intestine may be a major organ for initiating proline catabolism via proline oxidase in the body and is the major source of circulating citrulline and arginine in neonates, we hypothesized that lactate is an inhibitor of intestinal synthesis of citrulline and arginine from proline. To test this hypothesis, jejunum was obtained from 14-day-old suckling pigs for preparation of enterocyte mitochondria and metabolic studies. Mitochondria were used for measuring proline oxidase activity in the presence of 0-10 mM L-lactate. For metabolic studies, enterocytes were incubated at 37 degrees C for 30 min in Krebs bicarbonate buffer (pH 7.4) containing 5 mM D-glucose, 2 mM L-glutamine, 2 mM L-[U-14C]proline, and 0, 1, 5, or 10 mM L-lactate. Kinetics analysis revealed noncompetitive inhibition of intestinal proline oxidase by lactate (decreased maximal velocity and unaltered Michaelis constant). Lactate had no effect on either activities of other enzymes for arginine synthesis from proline or proline uptake by enterocytes but decreased the synthesis of ornithine, citrulline, and arginine from proline in a concentration-dependent manner. These results demonstrate that lactate decreased intestinal synthesis of citrulline and arginine from proline via an inhibition of proline oxidase and provide a biochemical basis for explaining hyperprolinemia, hypocitrullinemia, and hypoargininemia in infants with hyperlactacidemia.  (+info)

L-Citrulline is a non-essential amino acid that plays a role in the urea cycle, which is the process by which the body eliminates toxic ammonia from the bloodstream. It is called "non-essential" because it can be synthesized by the body from other compounds, such as L-Ornithine and carbamoyl phosphate.

Citrulline is found in some foods, including watermelon, bitter melon, and certain types of sausage. It is also available as a dietary supplement. In the body, citrulline is converted to another amino acid called L-Arginine, which is involved in the production of nitric oxide, a molecule that helps dilate blood vessels and improve blood flow.

Citrulline has been studied for its potential benefits on various aspects of health, including exercise performance, cardiovascular function, and immune system function. However, more research is needed to confirm these potential benefits and establish safe and effective dosages.

Ornithine is not a medical condition but a naturally occurring alpha-amino acid, which is involved in the urea cycle, a process that eliminates ammonia from the body. Here's a brief medical/biochemical definition of Ornithine:

Ornithine (NH₂-CH₂-CH₂-CH(NH₃)-COOH) is an α-amino acid without a carbon atom attached to the amino group, classified as a non-proteinogenic amino acid because it is not encoded by the standard genetic code and not commonly found in proteins. It plays a crucial role in the urea cycle, where it helps convert harmful ammonia into urea, which can then be excreted by the body through urine. Ornithine is produced from the breakdown of arginine, another amino acid, via the enzyme arginase. In some medical and nutritional contexts, ornithine supplementation may be recommended to support liver function, wound healing, or muscle growth, but its effectiveness for these uses remains a subject of ongoing research and debate.

Arginine is an α-amino acid that is classified as a semi-essential or conditionally essential amino acid, depending on the developmental stage and health status of the individual. The adult human body can normally synthesize sufficient amounts of arginine to meet its needs, but there are certain circumstances, such as periods of rapid growth or injury, where the dietary intake of arginine may become necessary.

The chemical formula for arginine is C6H14N4O2. It has a molecular weight of 174.20 g/mol and a pKa value of 12.48. Arginine is a basic amino acid, which means that it contains a side chain with a positive charge at physiological pH levels. The side chain of arginine is composed of a guanidino group, which is a functional group consisting of a nitrogen atom bonded to three methyl groups.

In the body, arginine plays several important roles. It is a precursor for the synthesis of nitric oxide, a molecule that helps regulate blood flow and immune function. Arginine is also involved in the detoxification of ammonia, a waste product produced by the breakdown of proteins. Additionally, arginine can be converted into other amino acids, such as ornithine and citrulline, which are involved in various metabolic processes.

Foods that are good sources of arginine include meat, poultry, fish, dairy products, nuts, seeds, and legumes. Arginine supplements are available and may be used for a variety of purposes, such as improving exercise performance, enhancing wound healing, and boosting immune function. However, it is important to consult with a healthcare provider before taking arginine supplements, as they can interact with certain medications and have potential side effects.

"Citrullus" is a genus of plants that includes watermelon and several other species of vine-like fruits. The name "Citrullus" comes from the Latin word for watermelon, "citrullus lanatus." Watermelons are the most well-known member of this genus and are popular for their juicy, sweet red or pink flesh, which is high in vitamins A and C and contains a high amount of lycopene. Other species in the Citrullus genus include citron melon (Citrullus lanatus var. citroides) and colocynth (Citrullus colocynthis), also known as bitter apple.

Ornithine carbamoyltransferase (OCT or OAT) is an enzyme that plays a crucial role in the urea cycle, which is the biochemical pathway responsible for the removal of excess nitrogen from the body. Specifically, ornithine carbamoyltransferase catalyzes the transfer of a carbamoyl group from carbamoyl phosphate to ornithine, forming citrulline and releasing phosphate in the process. This reaction is essential for the production of urea, which can then be excreted by the kidneys.

Deficiency in ornithine carbamoyltransferase can lead to a genetic disorder called ornithine transcarbamylase deficiency (OTCD), which is characterized by hyperammonemia (elevated blood ammonia levels) and neurological symptoms. OTCD is one of the most common urea cycle disorders, and it primarily affects females due to its X-linked inheritance pattern.

Hydrolases are a class of enzymes that help facilitate the breakdown of various types of chemical bonds through a process called hydrolysis, which involves the addition of water. These enzymes catalyze the cleavage of bonds in substrates by adding a molecule of water, leading to the formation of two or more smaller molecules.

Hydrolases play a crucial role in many biological processes, including digestion, metabolism, and detoxification. They can act on a wide range of substrates, such as proteins, lipids, carbohydrates, and nucleic acids, breaking them down into smaller units that can be more easily absorbed or utilized by the body.

Examples of hydrolases include:

1. Proteases: enzymes that break down proteins into smaller peptides or amino acids.
2. Lipases: enzymes that hydrolyze lipids, such as triglycerides, into fatty acids and glycerol.
3. Amylases: enzymes that break down complex carbohydrates, like starches, into simpler sugars, such as glucose.
4. Nucleases: enzymes that cleave nucleic acids, such as DNA or RNA, into smaller nucleotides or oligonucleotides.
5. Phosphatases: enzymes that remove phosphate groups from various substrates, including proteins and lipids.
6. Esterases: enzymes that hydrolyze ester bonds in a variety of substrates, such as those found in some drugs or neurotransmitters.

Hydrolases are essential for maintaining proper cellular function and homeostasis, and their dysregulation can contribute to various diseases and disorders.

Nitrogen isotopes are different forms of the nitrogen element (N), which have varying numbers of neutrons in their atomic nuclei. The most common nitrogen isotope is N-14, which contains 7 protons and 7 neutrons in its nucleus. However, there are also heavier stable isotopes such as N-15, which contains one extra neutron.

In medical terms, nitrogen isotopes can be used in research and diagnostic procedures to study various biological processes. For example, N-15 can be used in a technique called "nitrogen-15 nuclear magnetic resonance (NMR) spectroscopy" to investigate the metabolism of nitrogen-containing compounds in the body. Additionally, stable isotope labeling with nitrogen-15 has been used in clinical trials and research studies to track the fate of drugs and nutrients in the body.

In some cases, radioactive nitrogen isotopes such as N-13 or N-16 may also be used in medical imaging techniques like positron emission tomography (PET) scans to visualize and diagnose various diseases and conditions. However, these applications are less common than the use of stable nitrogen isotopes.

Glutamine is defined as a conditionally essential amino acid in humans, which means that it can be produced by the body under normal circumstances, but may become essential during certain conditions such as stress, illness, or injury. It is the most abundant free amino acid found in the blood and in the muscles of the body.

Glutamine plays a crucial role in various biological processes, including protein synthesis, energy production, and acid-base balance. It serves as an important fuel source for cells in the intestines, immune system, and skeletal muscles. Glutamine has also been shown to have potential benefits in wound healing, gut function, and immunity, particularly during times of physiological stress or illness.

In summary, glutamine is a vital amino acid that plays a critical role in maintaining the health and function of various tissues and organs in the body.

Carbamyl Phosphate is a chemical compound that plays a crucial role in the biochemical process of nitrogen metabolism, particularly in the urea cycle. It is synthesized in the liver and serves as an important intermediate in the conversion of ammonia to urea, which is then excreted by the kidneys.

In medical terms, Carbamyl Phosphate Synthetase I (CPS I) deficiency is a rare genetic disorder that affects the production of Carbamyl Phosphate. This deficiency can lead to hyperammonemia, which is an excess of ammonia in the bloodstream, and can cause severe neurological symptoms and brain damage if left untreated.

It's important to note that while Carbamyl Phosphate is a critical component of the urea cycle, it is not typically used as a medication or therapeutic agent in clinical practice.

Nitric Oxide Synthase (NOS) is a group of enzymes that catalyze the production of nitric oxide (NO) from L-arginine. There are three distinct isoforms of NOS, each with different expression patterns and functions:

1. Neuronal Nitric Oxide Synthase (nNOS or NOS1): This isoform is primarily expressed in the nervous system and plays a role in neurotransmission, synaptic plasticity, and learning and memory processes.
2. Inducible Nitric Oxide Synthase (iNOS or NOS2): This isoform is induced by various stimuli such as cytokines, lipopolysaccharides, and hypoxia in a variety of cells including immune cells, endothelial cells, and smooth muscle cells. iNOS produces large amounts of NO, which functions as a potent effector molecule in the immune response, particularly in the defense against microbial pathogens.
3. Endothelial Nitric Oxide Synthase (eNOS or NOS3): This isoform is constitutively expressed in endothelial cells and produces low levels of NO that play a crucial role in maintaining vascular homeostasis by regulating vasodilation, inhibiting platelet aggregation, and preventing smooth muscle cell proliferation.

Overall, NOS plays an essential role in various physiological processes, including neurotransmission, immune response, cardiovascular function, and respiratory regulation. Dysregulation of NOS activity has been implicated in several pathological conditions such as hypertension, atherosclerosis, neurodegenerative diseases, and inflammatory disorders.

Citrullinemia is a rare inherited metabolic disorder characterized by the body's inability to properly process and eliminate certain toxic byproducts that are generated during the breakdown of proteins. This condition results from a deficiency of the enzyme argininosuccinate synthetase, which is required for the normal functioning of the urea cycle. The urea cycle is a series of biochemical reactions that occur in the liver and help to convert ammonia, a toxic substance, into urea, which can then be excreted by the kidneys.

There are two main types of citrullinemia: type I (also known as classic citrullinemia) and type II (also known as citrullinemia type II or adult-onset citrullinemia). Type I is typically more severe and can present in newborns with symptoms such as poor feeding, vomiting, seizures, and developmental delays. If left untreated, it can lead to serious complications, including intellectual disability, coma, and even death.

Type II citrullinemia, on the other hand, tends to present later in life, often in adulthood, and may cause symptoms such as confusion, seizures, and neurological problems. It is important to note that some individuals with type II citrullinemia may never develop any symptoms at all.

Treatment for citrullinemia typically involves a combination of dietary restrictions, supplements, and medications to help manage the buildup of toxic byproducts in the body. In severe cases, liver transplantation may be considered as a last resort.

Argininosuccinate Lyase is an enzyme that plays a crucial role in the urea cycle, which is the metabolic pathway responsible for eliminating excess nitrogen waste from the body. This enzyme is responsible for catalyzing the conversion of argininosuccinate into arginine and fumarate.

The urea cycle occurs primarily in the liver and helps to convert toxic ammonia, a byproduct of protein metabolism, into urea, which can be safely excreted in urine. Argininosuccinate lyase is essential for this process, as it helps to convert argininosuccinate, an intermediate compound in the cycle, into arginine, which can then be recycled back into the urea cycle or used for other physiological processes.

Deficiencies in argininosuccinate lyase can lead to a rare genetic disorder known as citrullinemia, which is characterized by elevated levels of citrulline and ammonia in the blood, as well as neurological symptoms such as seizures, developmental delays, and intellectual disability. Treatment for citrullinemia typically involves a low-protein diet, supplementation with arginine and other essential amino acids, and in some cases, liver transplantation.

Arginase is an enzyme that plays a role in the metabolism of arginine, an amino acid. It works by breaking down arginine into ornithine and urea. This reaction is part of the urea cycle, which helps to rid the body of excess nitrogen waste produced during the metabolism of proteins. Arginase is found in various tissues throughout the body, including the liver, where it plays a key role in the detoxification of ammonia.

Proline is an organic compound that is classified as a non-essential amino acid, meaning it can be produced by the human body and does not need to be obtained through the diet. It is encoded in the genetic code as the codon CCU, CCC, CCA, or CCG. Proline is a cyclic amino acid, containing an unusual secondary amine group, which forms a ring structure with its carboxyl group.

In proteins, proline acts as a structural helix breaker, disrupting the alpha-helix structure and leading to the formation of turns and bends in the protein chain. This property is important for the proper folding and function of many proteins. Proline also plays a role in the stability of collagen, a major structural protein found in connective tissues such as tendons, ligaments, and skin.

In addition to its role in protein structure, proline has been implicated in various cellular processes, including signal transduction, apoptosis, and oxidative stress response. It is also a precursor for the synthesis of other biologically important compounds such as hydroxyproline, which is found in collagen and elastin, and glutamate, an excitatory neurotransmitter in the brain.

Ammonia is a colorless, pungent-smelling gas with the chemical formula NH3. It is a compound of nitrogen and hydrogen and is a basic compound, meaning it has a pH greater than 7. Ammonia is naturally found in the environment and is produced by the breakdown of organic matter, such as animal waste and decomposing plants. In the medical field, ammonia is most commonly discussed in relation to its role in human metabolism and its potential toxicity.

In the body, ammonia is produced as a byproduct of protein metabolism and is typically converted to urea in the liver and excreted in the urine. However, if the liver is not functioning properly or if there is an excess of protein in the diet, ammonia can accumulate in the blood and cause a condition called hyperammonemia. Hyperammonemia can lead to serious neurological symptoms, such as confusion, seizures, and coma, and is treated by lowering the level of ammonia in the blood through medications, dietary changes, and dialysis.

Argininosuccinic acid is a chemical compound that is an intermediate in the metabolic pathway for the synthesis of arginine, an essential amino acid. This process occurs in the urea cycle, which is responsible for removing excess nitrogen from the body in the form of urea.

In the urea cycle, citrulline reacts with aspartate to form argininosuccinic acid, which is then converted into arginine and fumarate by the enzyme argininosuccinate lyase. Arginine is a semi-essential amino acid that plays important roles in various physiological processes, including protein synthesis, nitric oxide production, and hormone secretion.

Argininosuccinic aciduria is a rare inherited metabolic disorder caused by a deficiency of the enzyme argininosuccinate lyase. This results in an accumulation of argininosuccinic acid in the blood and urine, leading to hyperammonemia (elevated levels of ammonia in the blood), neurological symptoms, and developmental delay. Treatment typically involves a low-protein diet, supplementation with arginine and citrulline, and nitrogen scavenging medications to reduce ammonia levels.

Nitric oxide (NO) is a molecule made up of one nitrogen atom and one oxygen atom. In the body, it is a crucial signaling molecule involved in various physiological processes such as vasodilation, immune response, neurotransmission, and inhibition of platelet aggregation. It is produced naturally by the enzyme nitric oxide synthase (NOS) from the amino acid L-arginine. Inhaled nitric oxide is used medically to treat pulmonary hypertension in newborns and adults, as it helps to relax and widen blood vessels, improving oxygenation and blood flow.

Amino acid oxidoreductases are a class of enzymes that catalyze the reversible oxidation and reduction reactions involving amino acids. They play a crucial role in the metabolism of amino acids by catalyzing the interconversion of L-amino acids to their corresponding α-keto acids, while simultaneously reducing a cofactor such as NAD(P)+ or FAD.

The reaction catalyzed by these enzymes can be represented as follows:

L-amino acid + H2O + Coenzyme (Oxidized) → α-keto acid + NH3 + Coenzyme (Reduced)

Amino acid oxidoreductases are classified into two main types based on their cofactor requirements and reaction mechanisms. The first type uses FAD as a cofactor and is called amino acid flavoprotein oxidoreductases. These enzymes typically catalyze the oxidative deamination of L-amino acids to form α-keto acids, ammonia, and reduced FAD. The second type uses pyridine nucleotides (NAD(P)+) as cofactors and is called amino acid pyridine nucleotide-dependent oxidoreductases. These enzymes catalyze the reversible interconversion of L-amino acids to their corresponding α-keto acids, while simultaneously reducing or oxidizing NAD(P)H/NAD(P)+.

Amino acid oxidoreductases are widely distributed in nature and play important roles in various biological processes, including amino acid catabolism, nitrogen metabolism, and the biosynthesis of various secondary metabolites. Dysregulation of these enzymes has been implicated in several diseases, including neurodegenerative disorders and cancer. Therefore, understanding the structure, function, and regulation of amino acid oxidoreductases is crucial for developing novel therapeutic strategies to treat these diseases.

Urea is not a medical condition but it is a medically relevant substance. Here's the definition:

Urea is a colorless, odorless solid that is the primary nitrogen-containing compound in the urine of mammals. It is a normal metabolic end product that is excreted by the kidneys and is also used as a fertilizer and in various industrial applications. Chemically, urea is a carbamide, consisting of two amino groups (NH2) joined by a carbon atom and having a hydrogen atom and a hydroxyl group (OH) attached to the carbon atom. Urea is produced in the liver as an end product of protein metabolism and is then eliminated from the body by the kidneys through urination. Abnormal levels of urea in the blood, known as uremia, can indicate impaired kidney function or other medical conditions.

Catecholamine plasma membrane transport proteins, also known as neurotransmitter transporters or simply transporters, are a type of membrane protein responsible for the reuptake of catecholamines (such as dopamine, norepinephrine, and epinephrine) from the synaptic cleft back into the presynaptic neuron. These proteins play a crucial role in regulating neurotransmitter concentrations in the synapse and terminating neurotransmission. They are targets for various psychoactive drugs, including antidepressants, psychostimulants, and cocaine.

Mouth abnormalities, also known as oral or orofacial anomalies, refer to structural or functional differences or defects in the mouth and surrounding structures, including the lips, teeth, gums, palate, tongue, and salivary glands. These abnormalities can be present at birth (congenital) or acquired later in life due to injury, disease, or surgery. They can range from minor variations in size, shape, or position of oral structures to more significant anomalies that may affect speech, swallowing, chewing, breathing, and overall quality of life.

Examples of mouth abnormalities include cleft lip and palate, macroglossia (enlarged tongue), microglossia (small tongue), ankyloglossia (tongue-tie), high or narrow palate, bifid uvula (split uvula), dental malocclusion (misaligned teeth), supernumerary teeth (extra teeth), missing teeth, and various oral tumors or cysts. Some mouth abnormalities may require medical intervention, such as surgery, orthodontic treatment, or speech therapy, while others may not necessitate any treatment.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

Short Bowel Syndrome (SBS) is a malabsorption disorder that occurs when a significant portion of the small intestine has been removed or is functionally lost due to surgical resection, congenital abnormalities, or other diseases. The condition is characterized by an inability to absorb sufficient nutrients, water, and electrolytes from food, leading to diarrhea, malnutrition, dehydration, and weight loss.

The small intestine plays a crucial role in digestion and absorption of nutrients, and when more than 50% of its length is affected, the body's ability to absorb essential nutrients becomes compromised. The severity of SBS depends on the extent of the remaining small intestine, the presence or absence of the ileocecal valve (a sphincter that separates the small and large intestines), and the functionality of the residual intestinal segments.

Symptoms of Short Bowel Syndrome include:

1. Chronic diarrhea
2. Steatorrhea (fatty stools)
3. Dehydration
4. Weight loss
5. Fat-soluble vitamin deficiencies (A, D, E, and K)
6. Electrolyte imbalances
7. Malnutrition
8. Anemia
9. Bacterial overgrowth in the small intestine
10. Osteoporosis due to calcium and vitamin D deficiencies

Treatment for Short Bowel Syndrome typically involves a combination of nutritional support, medication, and sometimes surgical interventions. Nutritional management includes oral or enteral feeding with specially formulated elemental or semi-elemental diets, as well as parenteral nutrition (intravenous feeding) to provide essential nutrients that cannot be absorbed through the gastrointestinal tract. Medications such as antidiarrheals, H2 blockers, proton pump inhibitors, and antibiotics may also be used to manage symptoms and prevent complications. In some cases, intestinal transplantation might be considered for severe SBS patients who do not respond to other treatments.

Glutamates are the salt or ester forms of glutamic acid, which is a naturally occurring amino acid and the most abundant excitatory neurotransmitter in the central nervous system. Glutamate plays a crucial role in various brain functions, such as learning, memory, and cognition. However, excessive levels of glutamate can lead to neuronal damage or death, contributing to several neurological disorders, including stroke, epilepsy, and neurodegenerative diseases like Alzheimer's and Parkinson's.

Glutamates are also commonly found in food as a natural flavor enhancer, often listed under the name monosodium glutamate (MSG). While MSG has been extensively studied, its safety remains a topic of debate, with some individuals reporting adverse reactions after consuming foods containing this additive.

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.

Enterocytes are the absorptive cells that line the villi of the small intestine. They are a type of epithelial cell and play a crucial role in the absorption of nutrients from food into the bloodstream. Enterocytes have finger-like projections called microvilli on their apical surface, which increases their surface area and enhances their ability to absorb nutrients. They also contain enzymes that help digest and break down carbohydrates, proteins, and fats into smaller molecules that can be absorbed. Additionally, enterocytes play a role in the absorption of ions, water, and vitamins.

Diamino acids are a type of modified amino acids that contain two amino groups (-NH2) in their side chain. In regular amino acids, the side chain is composed of a specific arrangement of carbon, hydrogen, oxygen, and sometimes sulfur atoms. However, in diamino acids, one or both of the hydrogen atoms attached to the central carbon atom (alpha carbon) are replaced by amino groups.

There are two types of diamino acids: symmetric and asymmetric. Symmetric diamino acids have identical side chains on both sides of the alpha carbon atom, while asymmetric diamino acids have different side chains on each side.

Diamino acids play a crucial role in various biological processes, such as protein synthesis, cell signaling, and neurotransmission. They can be found naturally in some proteins or can be synthesized artificially for use in research and medical applications.

It is important to note that diamino acids are not one of the twenty standard amino acids that make up proteins. Instead, they are considered non-proteinogenic amino acids, which means they are not typically encoded by DNA and are not directly involved in protein synthesis. However, some modified forms of diamino acids can be found in certain proteins as a result of post-translational modifications.

Renal aminoacidurias are a group of inherited kidney disorders characterized by the abnormal excretion of amino acids in the urine (aminoaciduria). This condition results from defects in the renal tubular transport systems that are responsible for the reabsorption of amino acids from the filtrate in the kidneys.

There are several types of renal aminoacidurias, each associated with a specific genetic mutation affecting different transporter proteins in the proximal renal tubules. The most common type is cystinuria, which is caused by a defect in the transport system for four amino acids: cystine, ornithine, lysine, and arginine. Other types of renal aminoacidurias include Hartnup disorder, Lowe syndrome, and Dent disease, among others.

The clinical manifestations of renal aminoacidurias vary depending on the specific type and severity of the disorder. Some individuals may be asymptomatic or have only mild symptoms, while others may experience severe complications such as kidney stones, urinary tract infections, neurological symptoms, or growth retardation.

Treatment for renal aminoacidurias typically involves dietary modifications, increased fluid intake, and medications to reduce the risk of kidney stone formation and other complications. In some cases, surgery may be necessary to remove large kidney stones.

Ornithine-oxo-acid transaminase (OAT), also known as ornithine aminotransferase, is a urea cycle enzyme that catalyzes the reversible transfer of an amino group from ornithine to α-ketoglutarate, producing glutamate semialdehyde and glutamate. This reaction is an essential part of the urea cycle, which is responsible for the detoxification of ammonia in the body. Deficiencies in OAT can lead to a genetic disorder called ornithine transcarbamylase deficiency (OTCD), which can cause hyperammonemia and neurological symptoms.

Amino acid transport systems are specialized cellular mechanisms responsible for the active transport of amino acids across cell membranes. These systems are essential for maintaining proper amino acid homeostasis within cells and organisms. They consist of several types of transporters that can be categorized based on their energy source, electrochemical gradient, substrate specificity, and functional characteristics.

The term 'basic' in this context typically refers to the fundamental understanding of these transport systems, including their structure, function, regulation, and physiological roles. Amino acid transport systems play a crucial role in various biological processes, such as protein synthesis, neurotransmission, cell signaling, and energy metabolism.

There are two primary types of amino acid transport systems:

1. **Na+-dependent transporters:** These transporters utilize the sodium gradient across the cell membrane to drive the uptake of amino acids. They can be further divided into subtypes based on their substrate specificity and functional properties, such as system A, system ASC, system B0, system B, system L, and system y+.
2. **Na+-independent transporters:** These transporters do not rely on the sodium gradient for amino acid transport. Instead, they use other energy sources like proton gradients or direct coupling to membrane potential. Examples of Na+-independent transporters include system L, system y+, and system x-AG.

Understanding the basic aspects of amino acid transport systems is essential for elucidating their roles in health and disease. Dysregulation of these systems has been implicated in various pathological conditions, such as neurological disorders, cancer, and metabolic diseases.

Ornithine Carbamoyltransferase (OCT) Deficiency Disease, also known as Ornithine Transcarbamylase Deficiency, is a rare inherited urea cycle disorder. It is caused by a deficiency of the enzyme ornithine carbamoyltransferase, which is responsible for one of the steps in the urea cycle that helps to rid the body of excess nitrogen (in the form of ammonia).

When OCT function is impaired, nitrogen accumulates and forms ammonia, leading to hyperammonemia (elevated blood ammonia levels), which can cause neurological symptoms such as lethargy, vomiting, irritability, and in severe cases, coma or death.

Symptoms of OCT deficiency can range from mild to severe and may include developmental delay, seizures, behavioral changes, and movement disorders. The diagnosis is typically made through newborn screening tests, enzyme assays, and genetic testing. Treatment usually involves a combination of dietary restrictions, medications that help remove nitrogen from the body, and in some cases, liver transplantation.

Carbon isotopes are variants of the chemical element carbon that have different numbers of neutrons in their atomic nuclei. The most common and stable isotope of carbon is carbon-12 (^{12}C), which contains six protons and six neutrons. However, carbon can also come in other forms, known as isotopes, which contain different numbers of neutrons.

Carbon-13 (^{13}C) is a stable isotope of carbon that contains seven neutrons in its nucleus. It makes up about 1.1% of all carbon found on Earth and is used in various scientific applications, such as in tracing the metabolic pathways of organisms or in studying the age of fossilized materials.

Carbon-14 (^{14}C), also known as radiocarbon, is a radioactive isotope of carbon that contains eight neutrons in its nucleus. It is produced naturally in the atmosphere through the interaction of cosmic rays with nitrogen gas. Carbon-14 has a half-life of about 5,730 years, which makes it useful for dating organic materials, such as archaeological artifacts or fossils, up to around 60,000 years old.

Carbon isotopes are important in many scientific fields, including geology, biology, and medicine, and are used in a variety of applications, from studying the Earth's climate history to diagnosing medical conditions.

Biopterin is a type of pteridine compound that acts as a cofactor in various biological reactions, particularly in the metabolism of amino acids such as phenylalanine and tyrosine. It plays a crucial role in the production of neurotransmitters like dopamine, serotonin, and noradrenaline. Biopterin exists in two major forms: tetrahydrobiopterin (BH4) and dihydrobiopterin (BH2). BH4 is the active form that participates in enzymatic reactions, while BH2 is an oxidized form that can be reduced back to BH4 by the action of dihydrobiopterin reductase.

Deficiencies in biopterin metabolism have been linked to several neurological disorders, including phenylketonuria (PKU), dopamine-responsive dystonia, and certain forms of autism. In these conditions, the impaired synthesis or recycling of biopterin can lead to reduced levels of neurotransmitters, causing various neurological symptoms.

In a medical context, nitrites are typically referred to as organic compounds that contain a functional group with the formula R-N=O, where R represents an alkyl or aryl group. They are commonly used in medicine as vasodilators, which means they widen and relax blood vessels, improving blood flow and lowering blood pressure.

One example of a nitrite used medically is amyl nitrite, which was previously used to treat angina pectoris, a type of chest pain caused by reduced blood flow to the heart muscle. However, its use has largely been replaced by other medications due to safety concerns and the availability of more effective treatments.

It's worth noting that inorganic nitrites, such as sodium nitrite, are also used in medicine for various purposes, including as a preservative in food and as a medication to treat cyanide poisoning. However, these compounds have different chemical properties and uses than organic nitrites.

Phenylbutyrates are a class of medications that are used primarily for the treatment of urea cycle disorders, which are rare genetic conditions that can lead to high levels of ammonia in the blood. The most common medication in this class is sodium phenylbutyrate, which is a salt of phenylbutyric acid.

Phenylbutyrates work by providing an alternative pathway for the elimination of excess nitrogen from the body. In urea cycle disorders, the body is unable to properly convert nitrogen into urea, leading to a buildup of ammonia in the blood. Phenylbutyrates can be converted into phenylacetate in the body, which can then bind with nitrogen and be excreted in the urine, helping to reduce the levels of ammonia in the blood.

In addition to their use in urea cycle disorders, phenylbutyrates have also been studied for their potential therapeutic benefits in other conditions, such as cancer, neurodegenerative diseases, and inherited metabolic disorders. However, more research is needed to fully understand their mechanisms of action and potential therapeutic uses.

Orotic acid, also known as pyrmidine carboxylic acid, is a organic compound that plays a role in the metabolic pathway for the biosynthesis of pyrimidines, which are nitrogenous bases found in nucleotides and nucleic acids such as DNA and RNA. Orotic acid is not considered to be a vitamin, but it is sometimes referred to as vitamin B13 or B15, although these designations are not widely recognized by the scientific community.

In the body, orotic acid is converted into orotidine monophosphate (OMP) by the enzyme orotate phosphoribosyltransferase. OMP is then further metabolized to form uridine monophosphate (UMP), a pyrimidine nucleotide that is an important precursor for the synthesis of RNA and other molecules.

Elevated levels of orotic acid in the urine, known as orotic aciduria, can be a sign of certain genetic disorders that affect the metabolism of pyrimidines. These conditions can lead to an accumulation of orotic acid and other pyrimidine precursors in the body, which can cause a range of symptoms including developmental delays, neurological problems, and kidney stones. Treatment for these disorders typically involves dietary restrictions and supplementation with nucleotides or nucleosides to help support normal pyrimidine metabolism.

... is also made by enterocytes of the small intestine. Several proteins contain citrulline as a result of a post- ... "Was citrulline first a laxative substance? The truth about modern citrulline and its isolation" (PDF). Nihon Ishigaku Zasshi. [ ... Citrulline can be derived from: from arginine via nitric oxide synthase, as a byproduct of the production of nitric oxide for ... The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon. Although ...
Ornithine and citrulline occur in the urea cycle, part of amino acid catabolism (see below). In addition to primary metabolism ... Curis, E.; Nicolis, I.; Moinard, C.; Osowska, S.; Zerrouk, N.; Bénazeth, S.; Cynober, L. (2005). "Almost all about citrulline ...
The amino acid citrulline is produced in watermelon rind. A number of cultivar groups have been identified: (syn. C. lanatus ... Rimando AM; Perkins-Veazie PM (2005). "Determination of citrulline in watermelon rind". J Chromatogr A. 1078 (1-2): 196-200. ...
Curis E, Nicolis I, Moinard C, Osowska S, Zerrouk N, Bénazeth S, Cynober L (November 2005). "Almost all about citrulline in ... ornithine and citrulline occur in the urea cycle, part of amino acid catabolism (see below). A rare exception to the dominance ...
Citrulline level in blood is decreased. Mitochondrial studies or NARP mtDNA evaluation plays a role in genetic diagnosis which ...
The reactions of the urea cycle 1 L-ornithine 2 carbamoyl phosphate 3 L-citrulline 4 argininosuccinate 5 fumarate 6 L-arginine ... A condensation reaction occurs between the amino group of aspartate and the carbonyl group of citrulline to form ... Carbamoyl phosphate is converted to citrulline. With catalysis by ornithine transcarbamylase, the carbamoyl phosphate group is ...
Ornithine transcarbamylase Citrulline Urea Cycle Bhagavan, N. V.; Ha, Chung-Eun (2015-01-01), Bhagavan, N. V.; Ha, Chung-Eun ( ... to form citrulline. It is produced from bicarbonate, ammonia (derived from amino acids), and phosphate (from ATP). The ...
L-citrulline + NH3 Thus, the two substrates of this enzyme are L-arginine and H2O, whereas its two products are L-citrulline ... RATNER S (1954). "Urea Synthesis and Metabolism of Arginine and Citrulline". Advances in Enzymology and Related Areas of ... Other names in common use include arginine dihydrolase, citrulline iminase, and L-arginine deiminase. This enzyme participates ...
Grisolia, S; Cohen, P P (1952). "The catalytic role of carbamyl glutamate in citrulline biosynthesis". J. Biol. Chem. 198 (2): ... Much of his first work concerned the biochemistry of citrulline, and he later worked on phosphoglycerate mutase, carbamoyl- ...
Jones, M. E.; Spector, L.; Lipmann, F. (February 1955). "Carbamyl Phosphate, the Carbamyl Donor in Enzymatic Citrulline ...
Jones ME, Spector L, Lipmann F (1955). "Carbamyl phosphate, the carbamyl donor in enzymatic citrulline synthesis". J. Am. Chem ...
It uses a valine-citrulline enzyme-cleavable linker. The linkage is stable in the bloodstream. The antibody binds to GPNMB on ...
Then, the enzymes citrulline and argininosuccinate convert ornithine to arginine. There are two distinct lysine biosynthetic ...
Stalon V, Vander Wauven C, Momin P, Legrain C (1987). "Catabolism of arginine, citrulline and ornithine by Pseudomonas and ...
Arginine and citrulline support the growth and reproduction of C. curtum. Parte, A.C. "Cryptobacterium". LPSN. Nakazawa F, Poco ... This bacterium is able to degrade arginine and produce substantial amounts of citrulline, ornithine and ammonia. ...
In the first step of the catalyzed reaction, citrulline attacks the α-phosphate of ATP to form citrulline adenylate, a reactive ... Additionally, attack by citrulline at the α-phosphate of ATP produces an equivalent of pyrophosphate, which can be hydrolyzed ... As a result, nitrogen (in the form of ammonia) and other byproducts of the urea cycle (such as citrulline) build up in the ... The transformation of citrulline into argininosuccinate is the rate-limiting step in arginine synthesis. The activity of ...
Diagnosis of citrullinemia type I is elevated citrulline in the blood.[citation needed] Type I citrullinemia is the most common ... Diagnosis of type II includes measuring decreased citrulline level and an increase in ammonium ions. These symptoms can be life ...
Deimination converts the amino acid arginine to the amino acid citrulline. This conversion is done by calcium-dependent enzymes ...
Citrulline is made from ornithine and carbamoyl phosphate by ornithine carbamoyltransferase. Arginine is then synthesized from ... citrulline in the urea cycle by the sequential action of the cytosolic enzymes argininosuccinate synthetase (ASS) and ...
... is one methylene group longer than citrulline, but similar in structure. The metabolite is generated from a ... Koshiishi I, Kobori Y, Imanari T: Determination of citrulline and homocitrulline by high-performance liquid chromatography with ... Different amounts of protein-bound citrulline and homocitrulline in foot joint tissues of a patient with anti-citrullinated ... low creatine excretion and effect of citrulline, arginine, or ornithine supplement. Pediatr Res. 1987 Sep;22(3):364-7. Evered ...
It has also been used to attach chemical payload (probes) to the amino acid citrulline and to peptides/proteins. Like some ... Bicker KL, Subramanian V, Chumanevich AA, Hofseth LJ, Thompson PR (2012). "Seeing citrulline: development of a phenylglyoxal- ...
Other names in common use include citrulline ureidase, citrulline hydrolase, and L-citrulline 5-N-carbamoyldihydrolase. Hill DL ... In enzymology, a citrullinase (EC 3.5.1.20) is an enzyme that catalyzes the chemical reaction L-citrulline + H2O ⇌ {\ ... The systematic name of this enzyme class is L-citrulline N5-carbamoyldihydrolase. ... displaystyle \rightleftharpoons } L-ornithine + CO2 + NH3 Thus, the two substrates of this enzyme are L-citrulline and H2O, ...
Citrulline (sometimes as "watermelon extract") is used as an alternative or supplement to arginine, and is claimed to reduce ... Rhim HC, Kim SJ, Park J, Jang KM (December 2020). "Effect of citrulline on post-exercise rating of perceived exertion, muscle ... and Citrulline. In 2005, chemist Patrick Arnold formulated a pre-workout which contained a new ingredient called DMAA ( ...
... enhances the function of citrulline as part of the nitric oxide cycle. It is a cofactor and acts on glutathione ...
The urea cycle makes use of L-ornithine, carbamoyl phosphate, and L-citrulline. The electron transport chain oxidizes coenzymes ... The second step facilitated by ornithine transcarbamylase converts carbamoyl phosphate and ornithine into citrulline. After ...
Lysine, ornithine and citrulline all have an affinity for cyanophycin synthase (L-aspartate-adding) enzyme CphA. Wiefel, Bröker ... Wiefel L, Bröker A, Steinbüchel A (June 2011). "Synthesis of a citrulline-rich cyanophycin by use of Pseudomonas putida ATCC ... It was also determined that insoluble CGP only exhibited minuscule concentrations of citrulline while soluble CGP was able to ... conducted an experiment demonstrating that citrulline-rich cyanophycin can be produced through the introduction of a citrulline ...
However, trypsin is unable to cleave after a citrulline residue which is neutral. A missed cleavage after a citrulline residue ... Citrulline is not one of the 20 standard amino acids encoded by DNA in the genetic code. Instead, it is the result of a post- ... Citrullination is distinct from the formation of the free amino acid citrulline as part of the urea cycle or as a byproduct of ... Citrulline residues can be chemically modified with butanedione or by biotinylation prior to analysis, leading to a different ...
Some members of the family probably catalyze arginine/ornithine or citrulline/ornithine antiport. Ion transporter superfamily ... "A putative transport protein is involved in citrulline excretion and re-uptake during arginine deiminase pathway activity by ...
Raptopoulou A, Sidiropoulos P, Katsouraki M, Boumpas DT (2007). "Anti-citrulline antibodies in the diagnosis and prognosis of ... arginine amino acid residues can be enzymatically converted into citrulline residues in proteins such as vimentin, by a process ...
Some cells synthesize argininosuccinic acid from citrulline and aspartic acid and use it as a precursor for arginine in the ... Nakata, M.; Yada, T.; Nakagawa, S.; Kobayashi, K.; Maruyama, I. (1997-06-27). "Citrulline-argininosuccinate-arginine cycle ... urea cycle or citrulline-NO cycle. The enzyme that catalyzes the reaction is argininosuccinate synthetase. Argininosuccinic ...
Citrulline is also made by enterocytes of the small intestine. Several proteins contain citrulline as a result of a post- ... "Was citrulline first a laxative substance? The truth about modern citrulline and its isolation" (PDF). Nihon Ishigaku Zasshi. [ ... Citrulline can be derived from: from arginine via nitric oxide synthase, as a byproduct of the production of nitric oxide for ... The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon. Although ...
RNA (5-R(P*AP*CP*GP*GP*UP*UP*AP*GP*GP*UP*CP*GP*CP*U)-3)RNA (5-R(P*AP*GP*AP*AP*GP*GP*AP*GP*UP*GP*U)-3)CITRULLINE
Oral L-citrulline supplementation raises plasma L-arginine concentration and augments NO-dependent signalling. Our aim was to ... Citrulline-malate ingestion significantly increased the plasma concentration of citrulline, arginine, ornithine, urea, ... L-citrulline-malate influence over branched chain amino acid utilization during exercise Eur J Appl Physiol. 2010 Sep;110(2): ... Oral L-citrulline supplementation raises plasma L-arginine concentration and augments NO-dependent signalling. Our aim was to ...
Our results suggest that L-citrulline supplementation may reduce systolic BP. A significant reduction in diastolic BP was ... Effects of L-citrulline supplementation on blood pressure: A systematic review and meta-analysis Avicenna J Phytomed. 2019 Jan- ... Dosage of L-citrulline supplementation varied from 3 to 9 g/day. Duration of the intervention ranged between 1 and 17 weeks. ... Conclusion: Our results suggest that L-citrulline supplementation may reduce systolic BP. A significant reduction in diastolic ...
produkt b v hled n i pod t mito slovy: pure l-citrulline, pumpa, napumpovat, no, oxid dusnat , nitric oxide, nitric oxid, oxyd ... Produkt Pure L-Citrulline nab z 100% ist L-citrulin, aminokyselinu, kter se mezi sportovci vyu v hlavn pro tvorbu oxidu dusnat ... Produkt Pure L-Citrulline nab z 100% ist L-citrulin, aminokyselinu, kter se mezi sportovci vyu v hlavn pro tvorbu oxidu dusnat ... Produkt Pure L-Citrulline obsahuje p rodn fermentovan , farmaceuticky ist 100% L-citrulin, kter je vhodn hlavn pro zv en NO. Zv ...
The striking alteration was obtained in the citrulline accumulation. The tolerant melons accumulated 2 times more citrulline ... However, the citrulline contents of the sensitive CU-52 were 11.68 ,i,μ,/i,mol gDW,sup,−1,/sup, and ... After 12 days under salt and drought conditions, the citrulline contents were increased in the tolerant CU 196 to 25.10  ... the amount of citrulline accumulation in response to the given treatments might be considered as a novel biochemical indicator ...
Citrulline. Citrulline. Other name(s):. a-amino-d-ureido-n-valeric acid ... Citrulline is a nonessential amino acid. It removes ammonia from your body. It may also stimulate the immune system and boost ... There are no conditions that increase how much citrulline you need.. Side effects, toxicity, and interaction. Using a single ... Early studies show that citrulline doesnt help exercise performance. It may reduce neutrophilia. It may also improve symptoms ...
Nutrakeys pure Citrulline provides a 1500mg dose which su... ... NutraKey L-Citrulline. NutraKey L-Citrulline 15% OFF W/ CODE ... NutraKey L-Citrulline - Supports Body Detoxification Pathways, Decrease Recovery Time And Boost Nitric Oxide Production! ... Decrease quantity for NutraKey L-Citrulline Increase quantity for NutraKey L-Citrulline ... Citrulline works with Aminos Arginine & Ornithine to help rid the body of ammonia. Citrulline also provides a readily available ...
L-Citrulline - HPLC certified - 100% pure - no additives. Pure amino acid - Maximum bioavailability. ... L-Citrulline also relieves muscle fatigue through ammonia elimination. L-Citrulline helps to rid the body of ammonia, a toxic ... L-Citrulline is involved in the formation of urea in the liver which plays an important part in the removal of waste created by ... L-Citrulline is converted to L-Arginine in the body to support L-Arginine and nitric oxide levels. Increased production of ...
Save today on L-Citrulline 500mg 3.53 oz. from SOURCE NATURALS, VitaNet carries a large selection of SOURCE NATURALS products ... L-Citrulline Promotes Cardiovascular Health L-Citrulline is a natural amino acid that supports sports performance and good ... L-Citrulline helps the body rid itself of ammonia, a by-product of intense exercise. This clearing enables the body to recover ... L-Citrulline 2 g † Other Ingredients: gelatin (capsule), microcrystalline cellulose, colloidal silicon dioxide, and magnesium ...
CITRULLINE (UNII: 29VT07BGDA) (CITRULLINE - UNII:29VT07BGDA) CITRULLINE. 6 [hp_X] in 1 mL. ... Melatonin 6X, 12X, 30X, 100X, 6C, 30C, 200C, L-Arginine 6X, 12X, 30X, 100X, 6C, 30C, 200C, L-Citrulline 6X, 12X, 30X, 100X, 6C ... Label: VASCUFLOW (melatonin, l-arginine, l-citrulline, ubidecarenonum, lanosterol, mevalonolactone, squalene, calcarea ... melatonin, l-arginine, l-citrulline, ubidecarenonum, lanosterol, mevalonolactone, squalene, calcarea carbonica, cholesterinum, ...
In this work, we investigated the effect of l-citrulline on vascular smooth muscle cell proliferation. l-Citrulline (10−8 M) ... 0.1 for l-citrulline (10−8 M) (P , .001,n = 3). These findings suggest thatl-citrulline decreases vascular smooth muscle cell ... l-Citrulline, the By-Product of Nitric Oxide Synthesis, Decreases Vascular Smooth Muscle Cell Proliferation. Emilio Ruiz, ... l-Citrulline, the By-Product of Nitric Oxide Synthesis, Decreases Vascular Smooth Muscle Cell Proliferation. Emilio Ruiz, ...
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... , P. P. Shivgunde ... Tsuboi T, Maeda M, Hayashi T. Administration of L-arginine plus L-citrulline or L-citrulline alone successfully retarded ... Our results conclude that L-citrulline is a promising treatment option for treating hypertension, and L-citrulline can be ... L-citrulline protects from kidney damage in type 1 diabetic mice. Front Immunol 2013;4:480. [Crossref] [Google Scholar] [PubMed ...
Literature References: An amino acid, first isolated from the juice of watermelon, Citrullus vulgaris Schrad., Cucurbitaceae: Wada, Biochem. Z. 224, 420 (1930); isoln from casein: Wada, ibid. 257, 1 (1933). Synthesis from ornithine through copper complexes: Kurtz, J. Biol. Chem. 122, 477 (1938); by alkaline hydrolysis of arginine: Fox, ibid. 123, 687 (1938); from cyclopentanone oxime: Fox et al., J. Org. Chem. 6, 410 (1941). Crystallization: Matsuda et al., JP 71 174 (1971 to Ajinomoto), C.A. 74, 126056u (1971). Crystal and molecular structure: Naganathan, Venkatesan, Acta Crystallogr. 27B, 1079 (1971); Ashida et al., ibid. 28B, 1367 (1972). Use in asthenia and hepatic insufficiency: FR 2198739 (1974 to Hublot & Vallet), C.A. 82, 144952c (1975). Clinical trial in treatment of lysinuric protein intolerance: J. Rajantie et al., J. Pediatr. 97, 927 (1980); T. O. Carpenter et al., N. Engl. J. Med. 312, 290 (1985). ...
Directions Mix One Serving Of Citrulline Malate In 8-12 Ounces Of Your Favorite Beverages, Pre-Workout Or Post-Workout. For ... Mix One Serving Of Citrulline Malate In 8-12 Ounces Of Your Favorite Beverages, Pre-Workout Or Post-Workout. For Optimal ... Results, Consume Citrulline Malate Daily Before Exercise And Combined With Condense, Stimpact And/Or Noxygen. Do Not Exceed ...
The median number of citrulline samples per patient was 7 [3-16]. Median citrulline concentrations before conditioning and at D ... In the uper citrulline trajectorie, pts were significantly older (p=0.005). However, citrulline trajectories were not ... Citrulline, a non-essential amino acid produced exclusively by enterocytes in the small intestine and involved in the synthesis ... Serum citrulline was quantified by liquid chromatography in blood samples collected from consecutive patients who received an ...
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L-Citrulline helps the body rid itself of ammonia, a by-product of intense exercise. This clearing enables the body ... L-Citrulline Supports Exercise Recovery Energy and Detoxification L-Citrulline is a natural amino acid that supports sports ... L-Citrulline helps the body rid itself of ammonia, a by-product of intense exercise. This clearing enables the body to recover ... L-Citrulline is a natural amino acid that supports sports performance and good health, while at the same time helping the liver ...
To understand how citrulline might evoke an autoimmune reaction, we have studied T cell responses to citrulline-containing ... In this study, we demonstrate that the conversion of arginine to citrulline at the peptide side-chain position interacting with ... but recent work has identified posttranslationally modified proteins containing citrulline (deiminated arginine) as specific ... To understand how citrulline might evoke an autoimmune reaction, we have studied T cell responses to citrulline-containing ...
Arginine and Citrulline are two amino acids that are integral to protein metabolism and utilization, as well as to the ... Now Foods Citrulline 750 Mg 180 Capsules Now Foods Citrulline is a supplement that will help support a healthy immune system ... Now Foods L-Citrulline 1200mg 120 Tablets Now Foods L-Citrulline is a supplement that will support your overall healing process ... Now Foods Arginine 500 Mg Citrulline 250 Mg 120 Capsules. Arginine and citrulline are both amino acids that are important for ...
L-Citrulline is an amino acid that helps to increase nitric oxide levels in the body, leading to better blood flow and oxygen ... L-Citrulline is an amino acid that helps to increase nitric oxide levels in the body, leading to better blood flow and oxygen ...
Citrulline is a nonessential amino acid. It removes ammonia from your body. It may also stimulate the immune system and boost ... Early studies show that citrulline doesnt help exercise performance. It may reduce neutrophilia. It may also improve symptoms ... Further research is needed to determine if citrulline is helpful in these conditions. ...
Citrulline. Citrulline is a non-essential amino acid found in various dietary sources and synthesized within the human body. ... Circulatory Health: Citrulline is known to promote circulatory health by supporting blood vessel function and reducing blood ... In Beverage: L-Citrulline plays a crucial role in the beverage industry, serving as both a nutritional supplement and a flavor ... In Agriculture/Animal FeedL-Citrulline in Agriculture/Animal Feed: Recognized as a valuable nutritional supplement in the ...
Citrulline is an amino acid used to enhance nitric oxide (NO) production and for the detoxification of ammonia levels. Ammonia ... Citrulline works Arginine & Ornithine to help rid the body of ammonia. Citrulline also provides a readily available substrate ... Citrulline is an amino acid used to enhance nitric oxide (NO) production and for the detoxification of ammonia levels. Ammonia ... To maximize results, drink at least 64 oz of water daily while using L-Citrulline. For maximum benefit, take up to (6000mg) per ...
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L-Citrulline is an amino acid that helps to increase nitric oxide levels in the body, leading to better blood flow and oxygen ... L-Citrulline is an amino acid that helps to increase nitric oxide levels in the body, leading to better blood flow and oxygen ... Big 3 Essential Stack: Creatine, Glutamine, & Citrulline Essentials, MUSCLE BUILDING & RECOVERY The Big 3 contains Creatine ... Monohydrate, Glutamine, & Citrulline. All single-ingredient products contain zero fillers, excipients, artificial colors, or ...
Citrulline function Several proteins are known to contain citrulline as a result of a posttranslational modification. These ... Citrulline in thyroid disorders. Infertility: new potential pathways involved. Author: federica collino. Date: 30/05/2012 ... The organic compound citrulline is an α-amino acid. It is a key intermediate in the urea cycle, the pathway by which mammals ... The level of citrulline, the catabolic product of NOS activity, has been demonstrated to be a good parameter in studying NOS ...
  • Our aim was to evaluate the effects of diet supplementation with L-citrulline-malate prior to intense exercise on the metabolic handle of plasma amino acids and on the products of metabolism of arginine as creatinine, urea and nitrite and the possible effects on the hormonal levels. (nih.gov)
  • Seventeen voluntary male pre-professional cyclists were randomly assigned to one of two groups: control or supplemented (6 g L-citrulline-malate 2 h prior exercise) and participated in a 137-km cycling stage. (nih.gov)
  • L-citrulline-malate supplementation can enhance the use of amino acids, especially the branched chain amino acids during exercise and also enhance the production of arginine-derived metabolites such as nitrite, creatinine, ornithine and urea. (nih.gov)
  • Mix One Serving Of Citrulline Malate In 8-12 Ounces Of Your Favorite Beverages, Pre-Workout Or Post-Workout. (nutritionwholesalers.com)
  • For Optimal Results, Consume Citrulline Malate Daily Before Exercise And Combined With Condense, Stimpact And/Or Noxygen. (nutritionwholesalers.com)
  • Citrulline malate supplementation has been shown to reduce post-workout muscle soreness for up to 48 hours in trained athletes, while also reducing the sensation and onset of muscle fatigue. (pharmafreak.com)
  • Product in powder form supplementing the diet with citrulline malate, recommended for adults, during the period of high intensity exercise. (levrosupplements.com)
  • Evolite Citrulline Malate on tippkvaliteediga toidulisand, mis on tauriiniga rikastatud tsitrulliini allikas. (infoviking.ee)
  • The synergistic combination of L-citrulline amino acid and malic acid is L-citrulline malate. (ironbody.de)
  • Like all BioTech USA products, Citrulline Malate powder consists of safe and carefully selected ingredients. (ironbody.de)
  • Citrulline malate reduces the excess of lactate in order to better regenerate muscles after exercise, it also ensures maximum muscle oxygenation, increases the level of nitric oxide and reduces physical and mental fatigue. (fitlove.nl)
  • ALLMAX Citrulline Malate (150 portion. (topnutritionandfitness.com)
  • CITRULLINE MALATE améliore l'intensité de l'entraînement, l'endurance et la vitesse de récupération. (topnutritionandfitness.com)
  • En plus d'aider à l'administration et à l'absorption, le Malate joue un rôle essentiel dans le cycle du TCA (ou Krebs) qui produit de l'énergie dans les mitochondries. (topnutritionandfitness.com)
  • CITRULLINE MALATE improves training intensity, endurance and speed of recovery. (kineticnutrition.com.au)
  • Take 1 scoop (2 g) of ALLMAX Citrulline Malate [2:1] up to 3 times daily, upon waking and approx. (kineticnutrition.com.au)
  • Citrulline Malate is highly synergistic with Arginine, Beta-Alanine and Creatine supplementation. (kineticnutrition.com.au)
  • Citrulline is also produced as a byproduct of the enzymatic production of nitric oxide from the amino acid arginine, catalyzed by nitric oxide synthase. (wikipedia.org)
  • Citrulline can be derived from: from arginine via nitric oxide synthase, as a byproduct of the production of nitric oxide for signaling purposes from ornithine through the breakdown of proline or glutamine/glutamate from asymmetric dimethylarginine via DDAH Citrulline is made from ornithine and carbamoyl phosphate in one of the central reactions in the urea cycle. (wikipedia.org)
  • Arginine is first oxidized into N-hydroxyl-arginine, which is then further oxidized to citrulline concomitant with release of nitric oxide. (wikipedia.org)
  • These citrulline residues are generated by a family of enzymes called peptidylarginine deiminases (PADs), which convert arginine into citrulline in a process called citrullination or deimination with the help of calcium ions. (wikipedia.org)
  • Oral L-citrulline supplementation raises plasma L-arginine concentration and augments NO-dependent signalling. (nih.gov)
  • Citrulline works with Aminos Arginine & Ornithine to help rid the body of ammonia. (a1supplements.com)
  • Citrulline also provides a readily available substrate for arginine production, which is used for the production of nitric oxide. (a1supplements.com)
  • L-Citrulline is converted to L-Arginine in the body to support L-Arginine and nitric oxide levels. (nutrabio.com)
  • L-Citrulline helps to rid the body of ammonia, a toxic byproduct of protein metabolism and provides a readily available substrate for arginine production. (nutrabio.com)
  • L-citrulline (CIT), a natural precursor to L-arginine, is receiving attention due to many pieces of data from preclinical and clinical trials. (ijpsonline.com)
  • Citrulline, a non-essential amino acid produced exclusively by enterocytes in the small intestine and involved in the synthesis of L-arginine, is not metabolized by the liver. (confex.com)
  • Cutting edge: The conversion of arginine to citrulline allows for a hi" by Jonathan A. Hill, Scott Southwood et al. (uwo.ca)
  • The nature of the arthritogenic Ag is not known, but recent work has identified posttranslationally modified proteins containing citrulline (deiminated arginine) as specific targets of the IgG Ab response in RA patients. (uwo.ca)
  • In this study, we demonstrate that the conversion of arginine to citrulline at the peptide side-chain position interacting with the shared epitope significantly increases peptide-MHC affinity and leads to the activation CD4+ T cells in DR4-IE tg mice. (uwo.ca)
  • Arginine and citrulline are both amino acids that are important for protein metabolism, utilization and maintenance of muscle tissue. (mysupplementstore.com)
  • The citrullination process involves enzymatic conversion of arginine to citrulline. (diff.org)
  • Citrulline is an amino acid that is converted to L-arginine in the body during the urea cycle, alongside the other amino acid L-ornithine. (pharmafreak.com)
  • Supplementing with citrulline is a more effective way to raise arginine levels and enhance nitric oxide (NO) production in the body, rather than supplementing with arginine. (pharmafreak.com)
  • L-Citrulline is an amino acid that is converted to L-Arginine & Nitric Oxide. (blackmarketlabs.com)
  • L-Citrulline is one of the three dietary amino acids in the urea cycle, alongside L-arginine and L-Ornithine. (corebolics.com)
  • Taking L-Citrulline increases plasma levels of ornithine and arginine and improves the ammonia recycling process and nitric oxide metabolism. (corebolics.com)
  • Nitric oxide is produced when L-arginine, an amino acid found in the body, is converted from L-citrulline. (soulperformancenutrition.com)
  • When L-citrulline is converted to L-arginine in the body, it can help increase the production of nitric oxide, which leads to dilated blood vessels and improved blood flow. (soulperformancenutrition.com)
  • Your kidneys change L-Citrulline into another amino acid called L-arginine and a chemical called nitric oxide. (affirmscience.com)
  • You might be wondering why AFFIRM® has L-citrulline rather than L-arginine. (affirmscience.com)
  • Instead, L-Citrulline goes into the kidneys where it is rapidly converted into L-Arginine. (affirmscience.com)
  • Scientific studies have proven L-Citrulline supplementation increases blood levels of L-Arginine more effectively than supplementation of L-arginine alone. (affirmscience.com)
  • L-citrulline amino acid is what L-arginine and L-ornithine amino acids are made of. (ironbody.de)
  • Since the kidneys can store large amounts of citrulline but not arginine, citrulline is ostensibly the most vital endogenous regulator of nitric oxide production. (transparentlabs.com)
  • Untargeted metabolomics analysis of larvae revealed that arginine and proline metabolism was the primary pathway affected by PCP exposure, reflected by increased proline and decreased citrulline (CIT) contents, which were confirmed by quantitative data. (bvsalud.org)
  • NO synthase (NOS) activity in the soluble and particulate fractions was determined by measuring the conversion of L-[14C] arginine to L-[14C] citrulline. (cdc.gov)
  • However, non-protein α-AA (e.g., ornithine, citrulline, and homocysteine) and non-α AA (e.g., taurine and β-alanine) also play important roles in cell metabolism ( Amino acids: metabolism, functions, and nutrition, 2009 ). (diff.org)
  • Citrulline is generated from ornithine and carbamoyl phosphate in one of the central reactions in the urea cycle. (diff.org)
  • A mutant enzyme protein impairs the reaction that leads to condensation of carbamyl phosphate and ornithine to form citrulline. (medscape.com)
  • In its presence, ornithine combines with carbamoyl phosphate to form citrulline, which is then transported out of the mitochondria. (medscape.com)
  • For example, elevated ornithine indicates CPS deficiency or OTC deficiency, whereas elevated citrulline indicates citrullinemia. (msdmanuals.com)
  • In the present work, citrulline accumulation under salinity and drought conditions was compared, separately in tolerant and sensitive melons, with the alterations of proline, total amino acids, and osmotic potentials. (hindawi.com)
  • Nutrakey's pure Citrulline provides a 1500mg dose which supports muscular detoxification, enhances nitric oxide levels, boosts endurance, and leads to decreased recovery times. (a1supplements.com)
  • We aimed to conduct a systematic review and meta-analysis of clinical trials that examined the effects of L-citrulline supplementation on blood pressure (BP). (nih.gov)
  • Citrulline is an important intermediate in the urea cycle. (a1supplements.com)
  • L-Citrulline is involved in the formation of urea in the liver which plays an important part in the removal of waste created by the digestion, absorption, and metabolism of proteins. (nutrabio.com)
  • Citrulline is an amino acid used to enhance nitric oxide (NO) production and for the detoxification of ammonia levels. (a1supplements.com)
  • During the past decade research on L-Citrulline has shown it plays an important role in nitric oxide production, vascular health, muscle protein synthesis, ammonia elimination, and immune function. (nutrabio.com)
  • L-Citrulline also relieves muscle fatigue through ammonia elimination. (nutrabio.com)
  • L-Citrulline helps the body rid itself of ammonia, a by-product of intense exercise. (vitanetonline.com)
  • Citrulline plays a role in ATP production, increasing energy demands when required while also buffering buildup of ammonia in the muscle, reducing exercise fatigue and increasing workout endurance. (pharmafreak.com)
  • In addition, L-citrulline may help to reduce muscle soreness after exercise by removing waste products such as ammonia from the muscles. (soulperformancenutrition.com)
  • By removing ammonia from the muscles, L-citrulline may help to reduce muscle soreness and improve recovery time. (soulperformancenutrition.com)
  • Citrulline may support muscle recovery and reduce muscle soreness after exercise. (hhoya.com)
  • One way in which L-citrulline may enhance performance is by increasing the production of nitric oxide in the body. (soulperformancenutrition.com)
  • Several proteins contain citrulline as a result of a post-translational modification. (wikipedia.org)
  • Proteins that normally contain citrulline residues include myelin basic protein (MBP), filaggrin, and several histone proteins, whereas other proteins, such as fibrin and vimentin are susceptible to citrullination during cell death and tissue inflammation. (wikipedia.org)
  • Several proteins are known to contain citrulline as a result of a posttranslational modification. (diff.org)
  • Detectable antibodies against proteins containing citrulline were found in patients with rheumatoid arthritis. (diff.org)
  • Although the origin of this immune response is not known, detection of antibodies against citrulline (anti-citrullinated protein antibodies) containing proteins is becoming an important aspect in the diagnosis of rheumatoid arthritis. (diff.org)
  • With Transparent Labs Citrulline powder, you get 2,000 mg of fermented L-citrulline in each scoop to amplify blood flow, muscle pumps, and. (transparentlabs.com)
  • L-Citrulline 2 g † Other Ingredients: gelatin (capsule), microcrystalline cellulose, colloidal silicon dioxide, and magnesium stearate. (vitanetonline.com)
  • L-citrulline (46%), malic acid, anticakingagent (silicon dioxide). (ironbody.de)
  • Iga Antibody Laboratories manufactures the cyclic citrulline peptide ab igg/iga reagents distributed by Genprice. (rnaready.com)
  • The Cyclic Citrulline Peptide Ab Igg/Iga reagent is RUO (Research Use Only) to test human serum or cell culture lab samples. (rnaready.com)
  • and levels of liver enzymes, creatinine, and anti-nuclear and anti-citrulline peptide antibodies. (cdc.gov)
  • NutraKey L-Citrulline - Supports Body Detoxification Pathways, Decrease Recovery Time And Boost Nitric Oxide Production! (a1supplements.com)
  • Citrulline is a nonessential amino acid that is reported to be an efficient hydroxyl radical scavenger and is a strong antioxidant [ 11 ]. (hindawi.com)
  • L-citrulline, a natural antioxidant and nitric oxide donor, has beneficial cardiovascular properties. (ijpsonline.com)
  • In addition to these potential benefits, L-citrulline is also thought to have antioxidant properties, which may help to protect cells from damage caused by free radicals. (soulperformancenutrition.com)
  • It has been scientifically demonstrated that L-Citrulline improves erectile hardness in men with mild erectile dysfunction, and improved penile blood pressures and Nitric Oxide levels in rat experimental models. (affirmscience.com)
  • However, it is important to talk to a healthcare provider before taking L-citrulline or any other dietary supplement, as it can interact with certain medications and may not be appropriate for everyone. (soulperformancenutrition.com)
  • Citrulline (L-citrulline) - is a dietary supplement that benefits mainly in endurance sports by improving athletic performance and protecting muscle tissue, and is used to treat ailments such as: dementia, muscle weakness, fatigue, and it is also used for treatment of heart disease, high blood pressure and diabetes. (fitlove.nl)
  • L-Citrulline plays a crucial role in the beverage industry, serving as both a nutritional supplement and a flavor enhancer. (hhoya.com)
  • Our results conclude that L-citrulline is a promising treatment option for treating hypertension, and L-citrulline can be combined with spironolactone to get a synergistic effect in treating hypertension. (ijpsonline.com)
  • Adding L-Citrulline to your workout can help with an improved pump and increased vascularity. (blackmarketlabs.com)
  • Used as a sports performance and cardiovascular health supplement, L-Citrulline helps reduce fatigue and improve endurance. (blackmarketlabs.com)
  • Some studies suggest that citrulline may enhance athletic performance by reducing fatigue and increasing exercise capacity. (hhoya.com)
  • L-citrulline is thought to improve exercise performance by reducing fatigue and improving muscle function. (soulperformancenutrition.com)
  • 14 ] reported that the accumulated citrulline could contribute to the protection of green tissues from the secondary oxidative stress induced under drought conditions because it behaves in vitro as a more potent hydroxyl radical scavenger than compatible solutes like mannitol, proline, and glycine betaine. (hindawi.com)
  • In conclusion, L-citrulline is a promising supplement with potential benefits for cardiovascular health, exercise performance, and sexual function. (soulperformancenutrition.com)
  • Circulating citrulline concentration is a biomarker of intestinal functionality. (wikipedia.org)
  • Women who are pregnant or breastfeeding should not take citrulline supplements. (barnesjewish.org)
  • The Big 3 contains Creatine Monohydrate, Glutamine, & Citrulline. (vmisports.com)
  • Our results suggest that L-citrulline supplementation may reduce systolic BP. (nih.gov)
  • It could be interesting to know whether citrulline kinetics could also represent a biomarker for conditioning toxicity, non-relapse mortality (NRM), and GvHD. (confex.com)
  • 12 ] reported that citrulline effectively protects DNA and metabolic enzymes from oxidative injuries. (hindawi.com)
  • Compared to the deoxycorticosterone acetate group, the L-citrulline and spironolactone combination therapy dose-dependently ameliorated the elevated levels of different blood pressure parameters, improved cardiac hypertrophy, vascular reactivity, aorta relaxant responses and attenuated oxidative stress. (ijpsonline.com)
  • Citrulline is also made by enterocytes of the small intestine. (wikipedia.org)
  • Citrulline is known to promote circulatory health by supporting blood vessel function and reducing blood pressure. (hhoya.com)
  • L-Citrulline can actually reverse blood vessel lining dysfunctions by activating another very important compound for growing blood vessels called vascular endothelial growth factor (VEGF). (affirmscience.com)
  • Health L-Citrulline is a natural amino acid that supports sports performance and good health, while at the same time helping the liver detoxify. (vitanetonline.com)
  • The accumulation of citrulline in response to drought stress in wild watermelon is a unique phenomenon in C3 plants [ 13 ]. (hindawi.com)
  • When it comes to fruit, citrulline is found in large quantities in watermelon, for example. (ironbody.de)
  • L-citrulline is an amino acid that was first isolated from the rind of watermelon ( Citrullus lanatus ), hence the name "citrulline. (transparentlabs.com)
  • The main objective of this study was to find out whether citrulline can be used as a biochemical marker of salt and drought stresses in a melon screening studies. (hindawi.com)
  • Using the cutoff for the marker citrulline, the screening case was deemed uninformative. (medscape.com)
  • L-Citrulline is a non-proteinogenic amino acid that the body readily absorbs and stores in the kidneys to assist with hemodynamics, vascular tone, and nitrogen balance. (transparentlabs.com)
  • To understand how citrulline might evoke an autoimmune reaction, we have studied T cell responses to citrulline-containing peptides in HLA-DRB1*0401 transgenic (DR4-IE tg) mice. (uwo.ca)
  • In a previous study, we demonstrated that l -citrulline, the by-product of nitric oxide synthesis, could relax rabbit aortic rings by stimulating the guanylate cyclase-linked ANP receptor. (aspetjournals.org)
  • In addition, l -citrulline also inhibited serum-induced DNA synthesis, measured as 5-bromo-2′-deoxyuridine incorporation. (aspetjournals.org)
  • Moreover, l -citrulline inhibition of serum-stimulated DNA synthesis was abolished by HS-142-1 (10 −5 M), an ANP receptor antagonist. (aspetjournals.org)
  • These findings suggest that l -citrulline decreases vascular smooth muscle cell proliferation in the A10 cell line by acting on DNA synthesis by mechanisms that involve the ANP receptor. (aspetjournals.org)
  • Otherwise citrulline may also generated as intermediate of NO synthesis mediated by NO syntheses (NOS) (Figure 2). (diff.org)