G Ly C In E

G LY C IN E

Glycine is one of the non-essential amino acids and is used to help create muscle tissue and convert glucose into energy. It is also essential to maintaining healthy central nervous and digestive systems, and has recently been shown to provide protection via antioxidants from some types of cancer. Glycine is used in the body to help construct normal DNA and RNA strands—the genetic material needed for proper cellular function and formation. It helps prevent the breakdown of muscle by boosting the body’s levels of creatine, a compound that helps build muscle mass. High concentrations of glycine are found not only in the muscles, but in the skin and other connective tissues as well. Almost 1/3 of collagen, which keeps the skin and connective tissue firm and flexible, is composed of glycine. (High amounts of Glycine are also found in gelatin, which is a form of denatured collagen). Without glycine the body would not be able to repair damaged tissues; the skin would become slack as it succumbed to UV rays, oxidation, and free radical damage, and wounds would never heal. Glycine is considered a glucogenic amino acid, which means it helps supply the body with glucose needed for energy. It helps regulate blood sugar levels, and thus glycine supplementation may be useful for treating symptoms characterized by low energy and fatigue, such as hypoglycemia, anemia, and Chronic Fatigue Syndrome (CFS). Glycine is essential for a healthy, normally functioning digestive system. It helps regulate the synthesis of the bile acid used to digest fats, and is included in many commercial gastric antacid agents. Glycine is necessary for central nervous system function. Research has shown that this amino acid can help inhibit the neurotransmitters that cause seizure activity, hyperactivity, and manic (bipolar) depression. Glycine can also be converted to another neurotransmitter, serine, as needed, and may be beneficial in the management of schizophrenia. In one study, twenty-two schizophrenic patients, who did not initially respond to traditional treatments, added glycine to their ongoing antipsychotic medication and found that it significantly reduced their symptoms. Glycine intake among the participants ranged from 40 to 90 grams daily (0.8 grams per kilogram of body weight). More research concerning the effects of glycine on schizophrenia is underway. Studies have shown that glycine also helps improve memory retrieval loss in those that suffer from a wide variety of sleep-

depriving conditions, including schizophrenia, Parkinson’s disease, Huntington’s disease, jet lag, and overwork. Results from preliminary studies of glycine as a potential treatment for cancer have been promising, and suggest that it may help prevent the development of cancerous tumors and melanoma. In laboratory mice, dietary glycine prevented tumor growth by inhibiting angiogenisis, the process by which tumors develop their own blood supply. Glycine also seems to play a role in keeping the prostate healthy. In one study, glycine was shown to help reduce the symptoms of prostatic hyperplasia in men. High-protein foods, such as fish, meat, beans, milk, and cheese, are the best dietary sources of glycine. Glycine is also available in capsule and powder forms, and as part of many combination amino acid supplements. There have been no toxic effects associated with glycine, although some people have reported that taking this supplement causes stomach upset. Individuals with kidney or liver disease should not consume glycine without consulting their doctor. Taking any one amino acid supplement can cause a disruption of the citric acid or Krebs cycle, and cause a build-up of nitrogen or ammonia in the body, which makes the liver and kidneys work harder to remove waste. Anyone taking antispastic drugs should consult a physician before supplementing with glycine, since it theoretically could increase the effects of these medications A LA N I N E

Alanine, or L-alanine, is an amino acid that helps the body convert the simple sugar glucose into energy and eliminate excess toxins from the liver. Amino acids are the building blocks of protein, and are key to building strong, healthy muscles—alanine has been shown to help protect cells from being damaged during intense aerobic activity, when the body cannibalizes muscle protein to help produce energy. Alanine is crucial for preserving balanced levels of nitrogen and glucose in the body, which it does through a series of chemical actions called the alanine cycle. During the alanine cycle, any excess amino acids (proteins) in cells or tissues are transferred to a receptor molecule called pyruvate, which is produced by the breakdown of glucose. The pyruvate is then converted to alanine and transferred to the liver. The liver extracts nitrogen from alanine and converts some of it back into pyruvate, which can then be used to produce more

glucose. Any excess nitrogen is then converted into urea and passed out of the body during urination. This cycle, glucose—pyruvate— alanine—pyruvate—glucose, helps supply the body with the energy it needs to support cellular life. It also ensures that a constant supply of pyruvate is available to allow the synthesis of glucose and amino acids in the body. Alanine plays a key role in maintaining glucose levels and thus energy supplies in the body. Epstein-Barr virus and chronic fatigue syndrome have been linked to excessive alanine levels and low levels of tyrosine and phenylalanine. Alanine may help regulate blood sugar as well. Research has found that for people with insulin-dependent diabetes, taking an oral dose of L-alanine effectively prevents nighttime hypoglycemia.

Alanine is a nonessential amino acid, which means that a healthy body is able to manufacture its own supply of this substance. However, all amino acids may become essential (requiring dietary supplementation) if the body is for some reason unable to produce them. People with low-protein diets or eating disorders, liver disease, diabetes, or genetic conditions that cause Urea Cycle Disorders (UCDs), may need to take alanine supplements to avoid a deficiency. Low levels of alanine have been found in patients with hypoglycemia, diabetes, and hepatitis—it is not known at this time if alanine deficiency is the cause or result of these diseases. The body must have alanine to process the B vitamins so necessary for good health, especially vitamin B5 (pantothenic acid) and vitamin B6 (pyridoxine). Because fluid in the prostate gland contains alanine, it has been theorized that this amino acid may help treat benign prostatic hyperplasia (BPH), a condition in which the prostate becomes enlarged and causes urination discomfort. In one study, participants with BPH took 780 milligrams of alanine, glycine, and glutamic acid per day for two weeks, then 390 milligrams of these three amino acids for the next two and a half months, and saw a significant reduction in symptoms. Good sources of alanine are meat, poultry, eggs, dairy products, and fish. Some protein-rich plant foods like avocado also supply alanine. There are also a number of supplements containing alanine available on the market. However, keep in mind that taking any one amino acid could upset the balance of nitrogen in the body, and make it harder for

the liver and kidneys eliminate waste. People with liver or kidney disease should consult a physician before taking any amino acid supplement. A LA N I N E

From Wikipedia, the free encyclopedia

Jump to: navigation, search Alanine

IUPAC name

[show]

Identifiers CAS number

[56-41-7]

PubChem

5950

SMILES

[show]

Properties Molecular formula C3H7NO2

Molar mass

89.09 g mol−1

Supplementary data page Structure and properties

n, εr, etc.

Thermodynamic data

Phase behaviour Solid, liquid, gas

Spectral data

UV, IR, NMR, MS

Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references

Alanine (abbreviated as Ala or A)[1] is an α-amino acid with the chemical formula CH3CH(NH2)COOH. The L-isomer is one of the 20 proteinogenic amino acids, i.e. the building blocks of proteins. Its codons are GCU, GCC, GCA, and GCG. It is classified as a nonpolar amino acid. L-alanine is second only to leucine, accounting for 7.8% of the primary structure in a sample of 1,150 proteins.[2] D-alanine occurs in bacterial cell walls and in some peptide antibiotics.

Contents [hide]

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1 Structure 2 Sources o 2.1 Dietary Sources o 2.2 Biosynthesis o 2.3 Chemical Synthesis 3 Physiological function o 3.1 As a carrier of ammonia and of the carbon skeleton of pyruvate in alanine cycle o 3.2 Link to hypertension 4 Chemical properties o 4.1 Free radical stability 5 References

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6 See also

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[edit] Structure The α-carbon atom of alanine is bound with a methyl group (-CH3), making it one of the simplest α-amino acids with respect to molecular structure and also resulting in alanine being classified as an aliphatic amino acid. The methyl group of alanine is non-reactive and is thus almost never directly involved in protein function.

(S)-Alanine (left) and (R)-alanine (right) in zwitterionic form at neutral pH A high potency artificial sweetener, called suosan, is derived from beta-alanine[3].

[edit] Sources [edit] Dietary Sources Alanine is a nonessential amino acid, meaning it can be manufactured by the human body, and does not need to be obtained directly through the diet. Alanine is found in a wide variety of foods, but is particularly concentrated in meats. Good sources of alanine include: • •

Animal sources: meat, seafood, caseinate, dairy products, eggs, fish, gelatin, lactalbumin Vegetarian sources: beans, nuts, seeds, soy, whey, brewer's yeast, brown rice bran, corn, legumes, whole grains.

[edit] Biosynthesis Alanine can be manufactured in the body from pyruvate and branched chain amino acids such as valine, leucine, and isoleucine. Alanine is most commonly produced by reductive amination of pyruvate. Because transamination reactions are readily reversible and pyruvate pervasive, alanine can be easily formed and thus has close links to metabolic pathways such as glycolysis, gluconeogenesis, and the citric acid cycle. It also arises together with lactate and generates glucose from protein via the alanine cycle.

[edit] Chemical Synthesis Racemic alanine can be prepared via the condensation of acetaldehyde with ammonium chloride in the presence of potassium cyanide by the Strecker reaction.[4]

[edit] Physiological function [edit] As a carrier of ammonia and of the carbon skeleton of pyruvate in alanine cycle Alanine plays a key role in glucose-alanine cycle between tissues and liver. In muscle and other tissues that degrade amino acids for fuel, amino groups are collected in the form of glutamate by transamination. Glutamate can then transfer its amino group through the action of alanine aminotransferase to pyruvate, a product of muscle glycolysis, forming alanine and alpha-ketoglutarate. The alanine formed is passed into the blood and transported to the liver. A reverse of the alanine aminotransferase reaction takes place in liver. Pyruvate regenerated forms glucose through gluconeogenesis, which returns to muscle through the circulation system. Glutamate in the liver enters mitochondria and degrades into ammonium ion through the action of glutamate dehydrogenase, which in turn participate in the urea cycle to form urea.[5]

The glucose-alanine cycle enables pyruvate and glutamate to be removed from the muscle and find their way to the liver. Glucose is regenerated from pyruvate and then returned to muscle: the energetic burden of gluconeogenesis is thus imposed on the liver instead of the muscle. All available ATP in muscle is devoted to muscle contraction.[5]

[edit] Link to hypertension An international study led by Imperial College London found a correlation between high levels of alanine and higher blood pressure, energy intake, cholesterol levels, and body mass index.[6]

[edit] Chemical properties [edit] Free radical stability The deamination of an alanine molecule produces a stable alkyl free radical, CH3C•HCOO–. Deamination can be induced in solid or aqueous alanine by radiation.[7] This property of alanine is used in dosimetric measurements in radiotherapy. When normal alanine is irradiated, the radiation causes certain alanine molecules to become free radicals, and, as these radicals are stable, the free radical content[citation needed] can later be measured in order to find out how much radiation the alanine was exposed to. In this way, one can be assured that complex radiotherapy treatment plans will deliver the intended pattern of radiation dose.