Arginine
Encyclopedia
Arginine is an α-amino acid
. The L-form is one of the 20 most common natural amino acids. At the level of molecular genetics, in the structure of the messenger ribonucleic acid mRNA, CGU, CGC, CGA, CGG, AGA, and AGG, are the triplets of nucleotide bases or codons that codify for arginine during protein synthesis. In mammals, arginine is classified as a semiessential or conditionally essential amino acid, depending on the developmental stage and health status of the individual. Preterm infants are unable to synthesize or create arginine internally, making the amino acid nutritionally essential for them. There are some conditions that put an increased demand on the body for the synthesis of L-arginine, including surgical or other trauma, sepsis and burns. Arginine was first isolated from a lupin
seedling extract in 1886 by the Swiss chemist Ernst Schultze.
In general, most people do not need to take arginine supplements because the body usually produces enough.
side-chain of arginine consists of a 3-carbon aliphatic straight chain, the distal end of which is capped by a complex guanidinium
group.
With a pKa
of 12.48, the guanidinium group is positively charged in neutral, acidic and even most basic environments, and thus imparts basic chemical properties to arginine.
Because of the conjugation
between the double bond and the nitrogen lone pairs, the positive charge is delocalized, enabling the formation of multiple H-bonds
.
by the sequential action of the cytosolic enzymes argininosuccinate synthetase
(ASS) and argininosuccinate lyase (ASL). In terms of energy, this is costly, as the synthesis of each molecule of argininosuccinate requires hydrolysis of adenosine triphosphate
(ATP) to adenosine monophosphate
(AMP), i.e., two ATP equivalents. Taking an excess of arginine essentially gives more energy by saving ATPs that can be used elsewhere.
Citrulline can be derived from multiple sources:
The pathways linking arginine, glutamine
, and proline
are bidirectional. Thus, the net utilization or production of these amino acids is highly dependent on cell type and developmental stage.
On a whole-body basis, synthesis of arginine occurs principally via the intestinal–renal axis, wherein epithelial cells of the small intestine
, which produce citrulline
primarily from glutamine
and glutamate, collaborate with the proximal tubule cells of the kidney
, which extract citrulline from the circulation and convert it to arginine, which is returned to the circulation. As a consequence, impairment of small bowel or renal function can reduce endogenous arginine synthesis, thereby increasing the dietary requirement.
Synthesis of arginine from citrulline also occurs at a low level in many other cells, and cellular capacity for arginine synthesis can be markedly increased under circumstances that also induce iNOS
. Thus, citrulline, a coproduct of the NOS-catalyzed reaction, can be recycled to arginine in a pathway known as the citrulline-NO or arginine-citrulline pathway. This is demonstrated by the fact that in many cell types, citrulline can substitute for arginine to some degree in supporting NO synthesis. However, recycling is not quantitative because citrulline accumulates along with nitrate and nitrite, the stable end-products of NO, in NO-producing cells.
s or yohimbine
, has also been used as a treatment for erectile dysfunction
.
The benefits and functions attributed to oral supplementation of L-arginine include:
Incorporated in proteins, arginine can also be converted to citrulline by PAD enzymes. In addition, arginine can be methylated
by protein methyltransferases.
(Nitric Oxide), urea
, ornithine
, and agmatine
; is necessary for the synthesis of creatine
; and can also be used for the synthesis of polyamine
s (mainly through ornithine and to a lesser degree through agmatine), citrulline
, and glutamate. As a precursor of nitric oxide, arginine may have a role in the treatment of some conditions where vasodilation
is required. The presence of asymmetric dimethylarginine
(ADMA), a close relative, inhibits the nitric oxide reaction; therefore, ADMA is considered a marker for vascular disease
, just as L-arginine is considered a sign of a healthy endothelium
.
) provides effective relief from sensitive teeth by depositing a dentin
-like mineral
, containing calcium
and phosphate
, within the dentin tubules and in a protective layer on the dentin surface.
may be of benefit in the treatment of herpes simplex virus.
For more information, refer to Herpes - Treatment also see journal article.
(the heart's ability to pump). In fact, six more patients who were taking L-arginine died than those taking a placebo resulting in early termination of the study with the recommendation that the supplement not be used by heart attack patients. These findings suggest L-arginine is not beneficial post-heart-attack.
, and is used in growth hormone stimulation tests.. However, more recent research suggests that oral preparations of l-arginine are ineffective at increasing growth hormone levels despite being effective at increasing plasma levels of l-arginine.
.
(AS) is induced by the same mediators of septic
response — endotoxin
and cytokine
s — that induce nitric oxide synthase
(NOS), the enzyme
responsible for nitric oxide
synthesis.
salt of arginine can also be used during the treatment of alcoholic hepatitis and advanced cirrhosis.
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
. The L-form is one of the 20 most common natural amino acids. At the level of molecular genetics, in the structure of the messenger ribonucleic acid mRNA, CGU, CGC, CGA, CGG, AGA, and AGG, are the triplets of nucleotide bases or codons that codify for arginine during protein synthesis. In mammals, arginine is classified as a semiessential or conditionally essential amino acid, depending on the developmental stage and health status of the individual. Preterm infants are unable to synthesize or create arginine internally, making the amino acid nutritionally essential for them. There are some conditions that put an increased demand on the body for the synthesis of L-arginine, including surgical or other trauma, sepsis and burns. Arginine was first isolated from a lupin
Lupin
Lupinus, commonly known as Lupins or lupines , is a genus in the legume family . The genus comprises about 280 species , with major centers of diversity in South and western North America , and the Andes and secondary centers in the Mediterranean region and Africa Lupinus, commonly known as Lupins...
seedling extract in 1886 by the Swiss chemist Ernst Schultze.
In general, most people do not need to take arginine supplements because the body usually produces enough.
Structure
The amino acidAmino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
side-chain of arginine consists of a 3-carbon aliphatic straight chain, the distal end of which is capped by a complex guanidinium
Guanidine
Guanidine is a crystalline compound of strong alkalinity formed by the oxidation of guanine. It is used in the manufacture of plastics and explosives. It is found in urine as a normal product of protein metabolism. The molecule was first synthesized in 1861 by the oxidative degradation of an...
group.
Acid dissociation constant
An acid dissociation constant, Ka, is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction known as dissociation in the context of acid-base reactions...
of 12.48, the guanidinium group is positively charged in neutral, acidic and even most basic environments, and thus imparts basic chemical properties to arginine.
Because of the conjugation
Conjugated system
In chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in compounds with alternating single and multiple bonds, which in general may lower the overall energy of the molecule and increase stability. Lone pairs, radicals or carbenium ions may be part of the...
between the double bond and the nitrogen lone pairs, the positive charge is delocalized, enabling the formation of multiple H-bonds
Hydrogen bond
A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen or fluorine, that comes from another molecule or chemical group. The hydrogen must be covalently bonded to another electronegative atom to create the bond...
.
Dietary sources
Arginine is a conditionally nonessential amino acid, meaning most of the time it can be manufactured by the human body, and does not need to be obtained directly through the diet. The biosynthetic pathway however does not produce sufficient arginine, and some must still be consumed through diet. Individuals who have poor nutrition or certain physical conditions may be advised to increase their intake of foods containing arginine. Arginine is found in a wide variety of foods, including:- Animal sources
- dairy products (e.g., cottage cheeseCottage cheeseCottage cheese is a cheese curd product with a mild flavor. It is drained, but not pressed, so some whey remains and the individual curds remain loose. The curd is usually washed to remove acidity, giving sweet curd cheese. It is not aged or colored. Different styles of cottage cheese are made from...
, ricottaRicottaRicotta is an Italian dairy product made from sheep milk whey left over from the production of cheese. Although typically referred to as ricotta cheese, ricotta is not properly a cheese because it is not produced by coagulation of casein...
, milkMilkMilk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...
, yogurt, whey proteinWhey proteinWhey protein is a mixture of globular proteins isolated from whey, the liquid material created as a by-product of cheese production. Some preclinical studies in rodents have suggested that whey protein may possess anti-inflammatory or anti-cancer properties; however, human data is lacking...
drinks), beefBeefBeef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in...
, porkPorkPork is the culinary name for meat from the domestic pig , which is eaten in many countries. It is one of the most commonly consumed meats worldwide, with evidence of pig husbandry dating back to 5000 BC....
(e.g., bacon, ham), gelatinGelatinGelatin is a translucent, colorless, brittle , flavorless solid substance, derived from the collagen inside animals' skin and bones. It is commonly used as a gelling agent in food, pharmaceuticals, photography, and cosmetic manufacturing. Substances containing gelatin or functioning in a similar...
, poultryPoultryPoultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...
(e.g. chicken and turkey light meat), wild game (e.g. pheasant, quail), seafoodSeafoodSeafood is any form of marine life regarded as food by humans. Seafoods include fish, molluscs , crustaceans , echinoderms . Edible sea plants, such as some seaweeds and microalgae, are also seafood, and are widely eaten around the world, especially in Asia...
(e.g., halibut, lobster, salmon, shrimp, snails, tuna)- Plant sources
- wheat germ and flour, buckwheat, granolaGranolaGranola is a breakfast food and snack food, popular in North America, consisting of rolled oats, nuts, honey, and sometimes rice, that is usually baked until crisp. During the baking process the mixture is stirred to maintain a loose, breakfast cereal-type consistency...
, oatmealOatmealOatmeal is ground oat groats , or a porridge made from oats . Oatmeal can also be ground oat, steel-cut oats, crushed oats, or rolled oats....
, peanutPeanutThe peanut, or groundnut , is a species in the legume or "bean" family , so it is not a nut. The peanut was probably first cultivated in the valleys of Peru. It is an annual herbaceous plant growing tall...
s, nutsNut (fruit)A nut is a hard-shelled fruit of some plants having an indehiscent seed. While a wide variety of dried seeds and fruits are called nuts in English, only a certain number of them are considered by biologists to be true nuts...
(coconut, pecans, cashews, walnuts, almonds, Brazil nuts, hazelnuts, pinenuts), seedsSEEDSSEEDS is a voluntary organisation registered under the Societies Act of India....
(pumpkin, sesame, sunflower), chick peas, cooked soybeans, Phalaris canariensis (canaryseed or ALPISTE)
Biosynthesis
Arginine is synthesized from citrullineCitrulline
The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon, from which it was first isolated in 1930.It has the idealized formula H2NCNH3CHCO2H...
by the sequential action of the cytosolic enzymes argininosuccinate synthetase
Argininosuccinate synthetase
Argininosuccinate synthase is an enzyme that catalyzes the synthesis of argininosuccinate from citrulline and aspartateASS is responsible for the third step of the urea cycle and one of the reactions of the Citrulline-NO cycle.-Gene:...
(ASS) and argininosuccinate lyase (ASL). In terms of energy, this is costly, as the synthesis of each molecule of argininosuccinate requires hydrolysis of adenosine triphosphate
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...
(ATP) to adenosine monophosphate
Adenosine monophosphate
Adenosine monophosphate , also known as 5'-adenylic acid, is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid and the nucleoside adenosine. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine...
(AMP), i.e., two ATP equivalents. Taking an excess of arginine essentially gives more energy by saving ATPs that can be used elsewhere.
Citrulline can be derived from multiple sources:
- from arginine via nitric oxide synthaseNitric oxide synthaseNitric oxide synthases are a family of enzymes that catalyze the production of nitric oxide from L-arginine. NO is an important cellular signaling molecule, having a vital role in many biological processes...
(NOS) - from ornithineOrnithineOrnithine is an amino acid that plays a role in the urea cycle.-Role in urea cycle:L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen....
via catabolism of prolineProlineProline is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the α-amino group is secondary...
or glutamineGlutamineGlutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...
/glutamate - from asymmetric dimethylarginineAsymmetric dimethylarginineAsymmetric dimethylarginine is a naturally occurring chemical found in blood plasma. It is a metabolic by-product of continual protein modification processes in the cytoplasm of all human cells. It is closely related to L-arginine, a conditionally-essential amino acid...
(ADMA) via DDAH
The pathways linking arginine, glutamine
Glutamine
Glutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...
, and proline
Proline
Proline is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the α-amino group is secondary...
are bidirectional. Thus, the net utilization or production of these amino acids is highly dependent on cell type and developmental stage.
On a whole-body basis, synthesis of arginine occurs principally via the intestinal–renal axis, wherein epithelial cells of the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
, which produce citrulline
Citrulline
The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon, from which it was first isolated in 1930.It has the idealized formula H2NCNH3CHCO2H...
primarily from glutamine
Glutamine
Glutamine is one of the 20 amino acids encoded by the standard genetic code. It is not recognized as an essential amino acid but may become conditionally essential in certain situations, including intensive athletic training or certain gastrointestinal disorders...
and glutamate, collaborate with the proximal tubule cells of the kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
, which extract citrulline from the circulation and convert it to arginine, which is returned to the circulation. As a consequence, impairment of small bowel or renal function can reduce endogenous arginine synthesis, thereby increasing the dietary requirement.
Synthesis of arginine from citrulline also occurs at a low level in many other cells, and cellular capacity for arginine synthesis can be markedly increased under circumstances that also induce iNOS
Nitric oxide synthase
Nitric oxide synthases are a family of enzymes that catalyze the production of nitric oxide from L-arginine. NO is an important cellular signaling molecule, having a vital role in many biological processes...
. Thus, citrulline, a coproduct of the NOS-catalyzed reaction, can be recycled to arginine in a pathway known as the citrulline-NO or arginine-citrulline pathway. This is demonstrated by the fact that in many cell types, citrulline can substitute for arginine to some degree in supporting NO synthesis. However, recycling is not quantitative because citrulline accumulates along with nitrate and nitrite, the stable end-products of NO, in NO-producing cells.
Function
Arginine plays an important role in cell division, the healing of wounds, removing ammonia from the body, immune function, and the release of hormones. Arginine taken in combination with proanthocyanidinProanthocyanidin
Proanthocyanidins, also known as OPCs or condensed tannins, are a subgroup of the flavonoid class of polyphenols...
s or yohimbine
Yohimbine
Yohimbine is an alkaloid with stimulant and aphrodisiac effects found naturally in Pausinystalia yohimbe . It is also found naturally in Rauwolfia serpentina , Alchornea floribunda , along with several other active alkaloids...
, has also been used as a treatment for erectile dysfunction
Erectile dysfunction
Erectile dysfunction is sexual dysfunction characterized by the inability to develop or maintain an erection of the penis during sexual performance....
.
The benefits and functions attributed to oral supplementation of L-arginine include:
- Precursor for the synthesis of nitric oxideNitric oxideNitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...
(NO) - Reduces healing time of injuries (particularly bone)
- Quickens repair time of damaged tissue
- Helps decrease blood pressureBlood pressureBlood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
Proteins
The distributing basics of the moderate structure found in geometry, charge distribution and ability to form multiple H-bonds make arginine ideal for binding negatively charged groups. For this reason, arginine prefers to be on the outside of the proteins where it can interact with the polar environment.Incorporated in proteins, arginine can also be converted to citrulline by PAD enzymes. In addition, arginine can be methylated
Methylation
In the chemical sciences, methylation denotes the addition of a methyl group to a substrate or the substitution of an atom or group by a methyl group. Methylation is a form of alkylation with, to be specific, a methyl group, rather than a larger carbon chain, replacing a hydrogen atom...
by protein methyltransferases.
Precursor
Arginine is the immediate precursor of NONitric oxide
Nitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...
(Nitric Oxide), urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
, ornithine
Ornithine
Ornithine is an amino acid that plays a role in the urea cycle.-Role in urea cycle:L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen....
, and agmatine
Agmatine
Agmatine is the decarboxylation product of the amino acid arginine and is an intermediate in polyamine biosynthesis. It is discussed as a putative neurotransmitter. It is synthesized in the brain, stored in synaptic vesicles, accumulated by uptake, released by membrane depolarization, and...
; is necessary for the synthesis of creatine
Creatine
Creatine is a nitrogenous organic acid that occurs naturally in vertebrates and helps to supply energy to all cells in the body, primarily muscle. This is achieved by increasing the formation of Adenosine triphosphate...
; and can also be used for the synthesis of polyamine
Polyamine
A polyamine is an organic compound having two or more primary amino groups .This class of compounds includes several synthetic substances that are important feedstocks for the chemical industry, such as ethylene diamine , 1,3-diaminopropane , and hexamethylenediamine...
s (mainly through ornithine and to a lesser degree through agmatine), citrulline
Citrulline
The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon, from which it was first isolated in 1930.It has the idealized formula H2NCNH3CHCO2H...
, and glutamate. As a precursor of nitric oxide, arginine may have a role in the treatment of some conditions where vasodilation
Vasodilation
Vasodilation refers to the widening of blood vessels resulting from relaxation of smooth muscle cells within the vessel walls, particularly in the large arteries, smaller arterioles and large veins. The process is essentially the opposite of vasoconstriction, or the narrowing of blood vessels. When...
is required. The presence of asymmetric dimethylarginine
Asymmetric dimethylarginine
Asymmetric dimethylarginine is a naturally occurring chemical found in blood plasma. It is a metabolic by-product of continual protein modification processes in the cytoplasm of all human cells. It is closely related to L-arginine, a conditionally-essential amino acid...
(ADMA), a close relative, inhibits the nitric oxide reaction; therefore, ADMA is considered a marker for vascular disease
Vascular disease
Vascular disease is a form of cardiovascular disease primarily affecting the blood vessels.Some conditions, such as angina and myocardial ischemia, can be considered both vascular diseases and heart diseases .Cigarette smoking is the major risk factor....
, just as L-arginine is considered a sign of a healthy endothelium
Endothelium
The endothelium is the thin layer of cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. These cells are called endothelial cells. Endothelial cells line the entire circulatory system, from the heart...
.
Treatment of dentin hypersensitivity
Arginine (8%) in dental products (e.g., toothpasteToothpaste
Toothpaste is a paste or gel dentifrice used with a toothbrush as an accessory to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it serves as an abrasive that aids in removing the dental plaque and food from the teeth, assists in suppressing...
) provides effective relief from sensitive teeth by depositing a dentin
Dentin
Dentine is a calcified tissue of the body, and along with enamel, cementum, and pulp is one of the four major components of teeth. Usually, it is covered by enamel on the crown and cementum on the root and surrounds the entire pulp...
-like mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
, containing calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
and phosphate
Phosphate
A phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...
, within the dentin tubules and in a protective layer on the dentin surface.
Treatment of herpes simplex virus
An unproven claim is that a low ratio of arginine to lysineLysine
Lysine is an α-amino acid with the chemical formula HO2CCH4NH2. It is an essential amino acid, which means that the human body cannot synthesize it. Its codons are AAA and AAG....
may be of benefit in the treatment of herpes simplex virus.
For more information, refer to Herpes - Treatment also see journal article.
Possible increased risk of death after supplementation following heart attack
A clinical trial found that patients taking an L-arginine supplement following a heart attack found no change in the heart's vascular tone or decrease in the symptoms of congestive heart failureCongestive heart failure
Heart failure often called congestive heart failure is generally defined as the inability of the heart to supply sufficient blood flow to meet the needs of the body. Heart failure can cause a number of symptoms including shortness of breath, leg swelling, and exercise intolerance. The condition...
(the heart's ability to pump). In fact, six more patients who were taking L-arginine died than those taking a placebo resulting in early termination of the study with the recommendation that the supplement not be used by heart attack patients. These findings suggest L-arginine is not beneficial post-heart-attack.
Lung inflammation and asthma
The Mayo Clinic web page on L-arginine reports that inhalation of L-arginine can increase lung inflammation and worsen asthma.Growth hormone
Arginine may stimulate the secretion of growth hormoneGrowth hormone
Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...
, and is used in growth hormone stimulation tests.. However, more recent research suggests that oral preparations of l-arginine are ineffective at increasing growth hormone levels despite being effective at increasing plasma levels of l-arginine.
MELAS syndrome
Several trials delved into effects of L-arginine in MELAS syndrome, a mitochondrial diseaseMitochondrial disease
Mitochondrial diseases are a group of disorders caused by dysfunctional mitochondria, the organelles that are the "powerhouses" of the cell. Mitochondria are found in every cell of the human body except red blood cells...
.
Sepsis
Cellular arginine biosynthetic capacity determined by activity of argininosuccinate synthetaseArgininosuccinate synthetase
Argininosuccinate synthase is an enzyme that catalyzes the synthesis of argininosuccinate from citrulline and aspartateASS is responsible for the third step of the urea cycle and one of the reactions of the Citrulline-NO cycle.-Gene:...
(AS) is induced by the same mediators of septic
Septic
Septic may refer to:* Septic tank, a component of a small scale sewage disposal system* Septic equation, a polynomial equation of degree seven* Septic shock...
response — endotoxin
Endotoxin
Endotoxins are toxins associated with some Gram-negative bacteria. An "endotoxin" is a toxin that is a structural molecule of the bacteria that is recognized by the immune system.-Gram negative:...
and cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
s — that induce nitric oxide synthase
Nitric oxide synthase
Nitric oxide synthases are a family of enzymes that catalyze the production of nitric oxide from L-arginine. NO is an important cellular signaling molecule, having a vital role in many biological processes...
(NOS), the enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
responsible for nitric oxide
Nitric oxide
Nitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...
synthesis.
Malate salt
The malateMalate
Malate is the ionized form of malic acid. It is an important chemical compound in biochemistry. In the C4 carbon fixation process, malate is a source of CO2 in the Calvin cycle....
salt of arginine can also be used during the treatment of alcoholic hepatitis and advanced cirrhosis.
Pre-eclampsia
A preliminary study of supplementation with L-arginine and antioxidant vitamins showed that this combination may help to combat abnormally high blood pressure during high risk pregnancies.See also
- AAKG
- canavanineCanavanineL---Canavanine is a non-proteinogenic α-amino acid found in certain leguminous plants. It is structurally related to the proteinogenic α-amino acid L-arginine, the sole difference being the replacement of a methylene group in arginine with an oxa group in canavanine...
and canalineCanalineL-Canaline ) is a non-protein amino acid. The compound is found in legumes that contain [canavanine], from which it is produced by the action of arginase. The most common-used source for this amino acid is the jack bean, Canavalia ensiformis...
are toxic analogues of arginine and ornithine