ALANINE

Some important facts about Alanine:
The second simplest amino acid, but used the most in proteins. Alanine is a non-essential amino acid that is involved in the metabolism of tryptophan and the vitamin pyridoxine. The alpha-carbon in Alanine is substituted with a levorotatory (l)-methyl group, making it one of the simplest amino acids with respect to molecular structure. This amino acid is one of the most widely used in protein construction, averaging about 9 percent of average protein composition on a per-mole basis when compared with the other amino acids.
Alanine has little therapeutic role in humans, although it has been demonstrated to display a cholesterol-reducing effect in rats. Is an important source of energy for muscle tissue, the brain and central nervous system; strengthens the immune system by producing antibodies; helps in the metabolism of sugars and organic acids. Alanine is present in prostate fluid, and it may play a role in supporting prostate health. Research has shown that alanine taken in combination with glycine and glutamic acid may reduce the symptoms associated with benign prostatic hyperplasia(BPH).
As with the other amino acids, excellent sources of alanine include meat and poultry, fish, eggs, and dairy products. Some protein-rich plant foods also supply alanine. Alanine is a hydrophobic molecule. It is ambivalent, meaning that it can be inside or outside of the protein molecule. The alpha carbon of Alanine is optically active; in proteins, only the L-isomer is found. Alanine is the a-amino acid analog of the a-keto acid pyruvate, an intermediate in sugar metabolism. Alanine and pyruvate are interchangeable by a transamination reaction. .
beta-ALANINE - This is the only naturally occurring beta amino acid, however this biochemical is not used in the biosynthesis of any major proteins or enzymes. Structurally, the IUPAC name for beta-alanine would be 3- (or beta- ) aminopropionic acid. It is a component of the naturally occurring peptides carnosine and anserine and also of pantothenic acid (vitamin B-5) which itself is a component of coenzyme A. Under normal conditions, beta-alanine is metabolized into acetic acid.

Metabolism of alanine and the glucose-alanine cycle:
A side from its role in protein synthesis, alanine is second only to glutamine in prominence as a circulating amino acid. In this capacity it serves a unique role in the transfer of nitrogen from peripheral tissue to the liver. Alanine is transferred to the circulation by many tissues, but mainly by muscle, in which alanine is formed from pyruvate at a rate proportional to intracellular pyruvate levels. Liver accumulates plasma alanine, reverses the transamination that occurs in muscle, and proportionately increases urea production. The pyruvate is either oxidized or converted to glucose via gluconeogenesis. When alanine transfer from muscle to liver is coupled with glucose transport from liver back to muscle, the process is known as the glucose-alanine cycle. The key feature of the cycle is that in 1 molecule, alanine, peripheral tissue exports pyruvate and ammonia (which are potentially rate-limiting for metabolism) to the liver, where the carbon skeleton is recycled and most nitrogen eliminated.
. Additionally, during periods of fasting, skeletal muscle protein is degraded for the energy value of the amino acid carbons and alanine is a major amino acid in protein. The alanine then enters the blood stream and is transported to the liver. Within the liver alanine is converted back to pyruvate which is then a source of carbon atoms for gluconeogenesis. Alanine is also important in intertissue nitrogen transport as part of the glucose-alanine cycle. Alanine's catabolic pathway involves a simple aminotransferase reaction that directly produces pyruvate. Generally pyruvate produced by this pathway will result in the formation of oxaloacetate, although when the energy charge of a cell is low the pyruvate will be oxidized to CO2 and H2O via the PDH complex and the TCA cycle. This makes alanine a glucogenic amino acid.

Benefits of alanine:
It is required for the metabolism of glucose and tryptophan and beta-alanine is a constituent of vitamin B5 (pantothenic acid) as well as coenzyme A. It has also demonstrated a cholesterol-reducing effect in rats. People suffering from Epstein Barr (also sometimes referred to as glandular fever) as well as chronic fatigue syndrome; have been linked to excessively high levels of alanine while having low levels of tyrosine and phenylalanine.
Alanine plays a major role in the transfer of nitrogen from peripheral tissue to the liver. It aids in the metabolism of glucose, a simple carbohydrate that the body uses for energy. It also guards against the buildup of toxic substances that are released in the muscle cells when muscle protein is broken down to quickly meet energy needs, such as happens with aerobic exercise.
Research has found that for people with insulin-dependent diabetes, taking an oral dose of L-alanine can be more effective than a conventional bedtime snack in preventing nighttime hypoglycemia. .

Deficiency symptoms of alanine
As alanine is synthesized in the body so deficiency of alanine is unknown. It may occur in people whose diet is greatly deficient in proteins. Deficiencies of alanine have been found in patients with hypoglycemia, diabetes, and alcohol-induced hepatitis.

Symptoms of high intake:
Alanine does not have any side effects, but people with kidney or liver disease should not consume high intakes of amino acids without consulting a health care professional. High levels of alanine, along with low levels of tyrosine and phenylalanine, have been associated with the Epstein-Barr virus and chronic fatigue syndrome.

Daily requirement:
Most people do not need to supplement with alanine since it is well provided for in the diet, and can be synthesized from pyruvic acid (formed in the breakdown of carbohydrates). People on a very low protein diet, could be at risk of a deficiency. Most people do not need to supplement with alanine; for those who do use this amino acid as a supplement, appropriate amounts should be determined with the consultation of a physician.

When more is needed:
People on low protein diet may require extra supplements of alanine.