L-Glutamine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ Supplemental L-glutamine's possible immunomodulatory role may be accounted for in a number of ways. L-glutamine appears to play a major role in protecting the integrity of the gastrointestinal tract and, in particular, the large intestine. During catabolic states, the integrity of the intestinal mucosa may be compromised with consequent increased intestinal permeability and translocation of Gram-negative bacteria from the large intestine into the body. The demand for L-glutamine by the intestine, as well as by cells such as lymphocytes, appears to be much greater than that supplied by skeletal muscle, the major storage tissue for L-glutamine. L-glutamine is the preferred respiratory fuel for enterocytes, colonocytes and lymphocytes. Therefore, supplying supplemental L-glutamine under these conditions may do a number of things. For one, it may reverse the catabolic state by sparing skeletal muscle L-glutamine. It also may inhibit translocation of Gram-negative bacteria from the large intestine. L-glutamine helps maintain secretory IgA, which functions primarily by preventing the attachment of bacteria to mucosal cells. L-glutamine appears to be required to support the proliferation of mitogen-stimulated lymphocytes, as well as the production of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). It is also required for the maintenance of lymphokine-activated killer cells (LAK). L-glutamine can enhance phagocytosis by neutrophils and monocytes. It can lead to an increased synthesis of glutathione in the intestine, which may also play a role in maintaining the integrity of the intestinal mucosa by ameliorating oxidative stress. The exact mechanism of the possible immunomodulatory action of supplemental L-glutamine, however, remains unclear. It is conceivable that the major effect of L-glutamine occurs at the level of the intestine. Perhaps enteral L-glutamine acts directly on intestine-associated lymphoid tissue and stimulates overall immune function by that mechanism, without passing beyond the splanchnic bed. L-isoleucine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ (Applies to Valine, Leucine and Isoleucine) This group of essential amino acids are identified as the branched-chain amino acids, BCAAs. Because this arrangement of carbon atoms cannot be made by humans, these amino acids are an essential element in the diet. The catabolism of all three compounds initiates in muscle and yields NADH and FADH2 which can be utilized for ATP generation. The catabolism of all three of these amino acids uses the same enzymes in the first two steps. The first step in each case is a transamination using a single BCAA aminotransferase, with a-ketoglutarate as amine acceptor. As a result, three different a-keto acids are produced and are oxidized using a common branched-chain a-keto acid dehydrogenase, yielding the three different CoA derivatives. Subsequently the metabolic pathways diverge, producing many intermediates. The principal product from valine is propionylCoA, the glucogenic precursor of succinyl-CoA. Isoleucine catabolism terminates with production of acetylCoA and propionylCoA; thus isoleucine is both glucogenic and ketogenic. Leucine gives rise to acetylCoA and acetoacetylCoA, and is thus classified as strictly ketogenic. There are a number of genetic diseases associated with faulty catabolism of the BCAAs. The most common defect is in the branched-chain a-keto acid dehydrogenase. Since there is only one dehydrogenase enzyme for all three amino acids, all three a-keto acids accumulate and are excreted in the urine. The disease is known as Maple syrup urine disease because of the characteristic odor of the urine in afflicted individuals. Mental retardation in these cases is extensive. Unfortunately, since these are essential amino acids, they cannot be heavily restricted in the diet; ultimately, the life of afflicted individuals is short and development is abnormal The main neurological problems are due to poor formation of myelin in the CNS. L-leucine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ This group of essential amino acids are identified as the branched-chain amino acids, BCAAs. Because this arrangement of carbon atoms cannot be made by humans, these amino acids are an essential element in the diet. The catabolism of all three compounds initiates in muscle and yields NADH and FADH2 which can be utilized for ATP generation. The catabolism of all three of these amino acids uses the same enzymes in the first two steps. The first step in each case is a transamination using a single BCAA aminotransferase, with a-ketoglutarate as amine acceptor. As a result, three different a-keto acids are produced and are oxidized using a common branched-chain a-keto acid dehydrogenase, yielding the three different CoA derivatives. Subsequently the metabolic pathways diverge, producing many intermediates. The principal product from valine is propionylCoA, the glucogenic precursor of succinyl-CoA. Isoleucine catabolism terminates with production of acetylCoA and propionylCoA; thus isoleucine is both glucogenic and ketogenic. Leucine gives rise to acetylCoA and acetoacetylCoA, and is thus classified as strictly ketogenic. There are a number of genetic diseases associated with faulty catabolism of the BCAAs. The most common defect is in the branched-chain a-keto acid dehydrogenase. Since there is only one dehydrogenase enzyme for all three amino acids, all three a-keto acids accumulate and are excreted in the urine. The disease is known as Maple syrup urine disease because of the characteristic odor of the urine in afflicted individuals. Mental retardation in these cases is extensive. Unfortunately, since these are essential amino acids, they cannot be heavily restricted in the diet; ultimately, the life of afflicted individuals is short and development is abnormal The main neurological problems are due to poor formation of myelin in the CNS. L-methionine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ The mechanism of the possible anti-hepatotoxic activity of L-methionine is not entirely clear. It is thought that metabolism of high doses of acetaminophen in the liver lead to decreased levels of hepatic glutathione and increased oxidative stress. L-methionine is a precursor to L-cysteine. L-cysteine itself may have antioxidant activity. L-cysteine is also a precursor to the antioxidant glutathione. Antioxidant activity of L-methionine and metabolites of L-methionine appear to account for its possible anti-hepatotoxic activity. Recent research suggests that methionine itself has free-radical scavenging activity by virtue of its sulfur, as well as its chelating ability. L-phenylalanine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ The mechanism of L-phenylalanine's putative antidepressant activity may be accounted for by its precursor role in the synthesis of the neurotransmitters norepinephrine and dopamine. Elevated brain norepinephrine and dopamine levels are thought to be associated with antidepressant effects. The mechanism of L-phenylalanine's possible antivitiligo activity is not well understood. It is thought that L-phenylalanine may stimulate the production of melanin in the affected skin L-threonine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ L-Threonine is a precursor to the amino acids glycine and serine. It acts as a lipotropic in controlling fat build-up in the liver. May help combat mental illness and may be very useful in indigestion and intestinal malfunctions. Also, threonine prevents excessive liver fat. Nutrients are more readily absorbed when threonine is present. L-valine¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ (Applies to Valine, Leucine and Isoleucine) This group of essential amino acids are identified as the branched-chain amino acids, BCAAs. Because this arrangement of carbon atoms cannot be made by humans, these amino acids are an essential element in the diet. The catabolism of all three compounds initiates in muscle and yields NADH and FADH2 which can be utilized for ATP generation. The catabolism of all three of these amino acids uses the same enzymes in the first two steps. The first step in each case is a transamination using a single BCAA aminotransferase, with a-ketoglutarate as amine acceptor. As a result, three different a-keto acids are produced and are oxidized using a common branched-chain a-keto acid dehydrogenase, yielding the three different CoA derivatives. Subsequently the metabolic pathways diverge, producing many intermediates. The principal product from valine is propionylCoA, the glucogenic precursor of succinyl-CoA. Isoleucine catabolism terminates with production of acetylCoA and propionylCoA; thus isoleucine is both glucogenic and ketogenic. Leucine gives rise to acetylCoA and acetoacetylCoA, and is thus classified as strictly ketogenic. There are a number of genetic diseases associated with faulty catabolism of the BCAAs. The most common defect is in the branched-chain a-keto acid dehydrogenase. Since there is only one dehydrogenase enzyme for all three amino acids, all three a-keto acids accumulate and are excreted in the urine. The disease is known as Maple syrup urine disease because of the characteristic odor of the urine in afflicted individuals. Mental retardation in these cases is extensive. Unfortunately, since these are essential amino acids, they cannot be heavily restricted in the diet; ultimately, the life of afflicted individuals is short and development is abnormal The main neurological problems are due to poor formation of myelin in the CNS.
Pharmacology
L-Glutamine¿¡ ´ëÇÑ Pharmacology Á¤º¸ Like other amino acids, glutamine is biochemically important as a constituent of proteins. Glutamine is also crucial in nitrogen metabolism. Ammonia (formed by nitrogen fixation) is assimilated into organic compounds by converting glutamic acid to glutamine. The enzyme which accomplishes this is called glutamine synthetase. Glutamine can then be used as a nitrogen donor in the biosynthesis of many compounds, including other amino acids, purines, and pyrimidines. L-isoleucine¿¡ ´ëÇÑ Pharmacology Á¤º¸ They provide ingredients for the manufacturing of other essential biochemical components in the body, some of which are utilized for the production of energy, stimulants to the upper brain and helping you to be more alert. L-leucine¿¡ ´ëÇÑ Pharmacology Á¤º¸ An essential amino acid. (Claim) Leucine helps with the regulation of blood-sugar levels, the growth and repair of muscle tissue (such as bones, skin and muscles), growth hormone production, wound healing as well as energy regulation. It can assist to prevent the breakdown of muscle proteins that sometimes occur after trauma or severe stress. It may also be beneficial for individuals with phenylketonuria - a condition in which the body cannot metabolize the amino acid phenylalanine L-methionine¿¡ ´ëÇÑ Pharmacology Á¤º¸ L-Methionine is a principle supplier of sulfur which prevents disorders of the hair, skin and nails; helps lower cholesterol levels by increasing the liver's production of lecithin; reduces liver fat and protects the kidneys; a natural chelating agent for heavy metals; regulates the formation of ammonia and creates ammonia-free urine which reduces bladder irritation; influences hair follicles and promotes hair growth. L-methionine may protect against the toxic effects of hepatotoxins, such as acetaminophen. Methionine may have antioxidant activity. L-phenylalanine¿¡ ´ëÇÑ Pharmacology Á¤º¸ Used by the brain to produce Norepinephrine, a chemical that transmits signals between nerve cells and the brain; keeps you awake and alert; reduces hunger pains; functions as an antidepressant and helps improve memory. L-threonine¿¡ ´ëÇÑ Pharmacology Á¤º¸ L-Threonine is an essential amino acid that helps to maintain the proper protein balance in the body. It is important for the formation of collagen, elastin, and tooth enamel, and aids liver and lipotropic function when combined with aspartic acid and methionine. L-valine¿¡ ´ëÇÑ Pharmacology Á¤º¸ L-valine is a branched-chain essential amino acid (BCAA) that has stimulant activity. It promotes muscle growth and tissue repair. It is a precursor in the penicillin biosynthetic pathway. Valine is one of three branched-chain amino acids (the others are leucine and isoleucine) that enhance energy, increase endurance, and aid in muscle tissue recovery and repair. This group also lowers elevated blood sugar levels and increases growth hormone production. Supplemental valine should always be combined with isoleucine and leucine at a respective milligram ratio of 2:1:2. It is an essential amino acid found in proteins; important for optimal growth in infants and for growth in children and nitrogen balance in adults. The lack of L-valine may influence the growth of body, cause neuropathic obstacle, anaemia. It has wide applications in the field of pharmaceutical and food industry.
L-Glutamine¿¡ ´ëÇÑ Absorption Á¤º¸ Absorption is efficient and occurs by an active transport mechanism L-isoleucine¿¡ ´ëÇÑ Absorption Á¤º¸ Absorbed from the small intestine by a sodium-dependent active-transport process L-methionine¿¡ ´ëÇÑ Absorption Á¤º¸ Absorbed from the lumen of the small intestine into the enterocytes by an active transport process. L-phenylalanine¿¡ ´ëÇÑ Absorption Á¤º¸ Absorbed from the small intestine by a sodium dependent active transport process. L-valine¿¡ ´ëÇÑ Absorption Á¤º¸ Absorbed from the small intestine by a sodium-dependent active-transport process.
L-Glutamine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Enterocytes, Hepatic L-isoleucine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic L-methionine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic L-phenylalanine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic. L-phenylalanine that is not metabolized in the liver is distributed via the systemic circulation to the various tissues of the body, where it undergoes metabolic reactions similar to those that take place in the liver. L-threonine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic L-valine¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic
Toxicity
L-Glutamine¿¡ ´ëÇÑ Toxicity Á¤º¸ Doses of L-glutamine up to 21 grams daily appear to be well tolerated. Reported adverse reactions are mainly gastrointestinal and not common. They include constipation and bloating. There is one older report of two hypomanic patients whose manic symptoms were exacerbated following the use of 2 to 4 grams daily of L-glutamine. The symptoms resolved when the L-glutamine was stopped. These patients were not rechallenged, nor are there any other reports of this nature. L-isoleucine¿¡ ´ëÇÑ Toxicity Á¤º¸ Symptoms of hypoglycemia, increased mortality in ALS patients taking large doses of BCAAs L-methionine¿¡ ´ëÇÑ Toxicity Á¤º¸ Doses of L-methionine of up to 250 mg daily are generally well tolerated. Higher doses may cause nausea, vomiting and headache. Healthy adults taking 8 grams of L-methionine daily for four days were found to have reduced serum folate levels and leucocytosis. Healthy adults taking 13.9 grams of L-methionine daily for five days were found to have changes in serum pH and potassium and increased urinary calcium excretion. Schizophrenic patients given 10 to 20 grams of L-methionine daily for two weeks developed functional psychoses. Single doses of 8 grams precipitated encephalopathy in patients with cirrhosis. L-phenylalanine¿¡ ´ëÇÑ Toxicity Á¤º¸ L-phenylalanine will exacerbate symptoms of phenylketonuria if used by phenylketonurics. L-phenylalanine was reported to exacerbate tardive dyskinesia when used by some with schizophrenia. L-valine¿¡ ´ëÇÑ Toxicity Á¤º¸ Symptoms of hypoglycemia, increased mortality in ALS patients taking large doses of BCAAs.
Drug Interactions
L-Glutamine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available L-isoleucine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available L-methionine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available L-phenylalanine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available L-valine¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Not Available
L-Glutamine¿¡ ´ëÇÑ Description Á¤º¸ 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. [PubChem] L-isoleucine¿¡ ´ëÇÑ Description Á¤º¸ An essential branched-chain aliphatic amino acid found in many proteins. It is an isomer of leucine. It is important in hemoglobin synthesis and regulation of blood sugar and energy levels. [PubChem] L-leucine¿¡ ´ëÇÑ Description Á¤º¸ An essential branched-chain amino acid important for hemoglobin formation. [PubChem] L-methionine¿¡ ´ëÇÑ Description Á¤º¸ A sulfur containing essential amino acid that is important in many body functions. It is a chelating agent for heavy metals. [PubChem] L-phenylalanine¿¡ ´ëÇÑ Description Á¤º¸ An essential aromatic amino acid that is a precursor of melanin; dopamine; noradrenalin (norepinephrine), and thyroxine. [PubChem] L-threonine¿¡ ´ëÇÑ Description Á¤º¸ An essential amino acid occurring naturally in the L-form, which is the active form. It is found in eggs, milk, gelatin, and other proteins. [PubChem] L-valine¿¡ ´ëÇÑ Description Á¤º¸ A branched-chain essential amino acid that has stimulant activity. It promotes muscle growth and tissue repair. It is a precursor in the penicillin biosynthetic pathway. [PubChem]