Glutamine
Glutamine has a unique structure with each molecule containing two atoms of nitrogen instead of one -- an aspect that enables it to clear ammonia from the tisssues, especially the brain. Glutamine is also an important carrier of urinary ammonia, which is broken down in the kidneys by glutaminase.
Glutamine is the most abundant amino acid in the blood and cerebrospinal fluid, and is the only amino acid that easily passes the blood-brain barrier. In the brain, glutamine converts to glutamic acid, which is essential for cerebral function. While glutamic acid is probably the active form in the brain, it is glutamine that is more efficiently transported throughout the rest of the body, ultimately causing a higher glutamic acid concentration needed in the brain.
Glutamine is the dominant amino acid in muscle tissue, comprising some 61% of the total amino acid pool: a factor commonly utilized by body builders to help reduce muscle deterioration during workouts. Because of its unique structure, containing two nitrogen side chains, glutamine becomes the primary transporter of nitrogen into muscle cells where it is synthesized for growth. However, the demand for glutamine by the intestines, as well as by such cells as lymphocytes, appears to be much greater than what can be supplied by skeletal muscles, which are the major storage tissue for L-glutamine. Glutamine is also the preferred respiratory fuel for enterocytes, colonocytes and lymphocytes.
Free Form vs Peptide Bonded
Although glutamine has some great benefits, there are some who think the peptide-bonded form might actually work better. Much of the ingested free form L-glutamine does not make it into the blood stream or muscle tissue. It is estimated that anywhere from 50-85% is immediately used by the intestines, liver, and the immune system. This is what many scientists refer to as the “glutamine paradox": a problem which is apparently solved by using the glutamine peptide bonded chain.
Glutamine peptide is also much more stable in solution, higher temperatures, and low PH than free form L-glutamine since it tends to break down to ammonia and glutamic acid rather quickly in solution. The digestive tract has peptide transport systems that allow peptides to be better absorbed and utilized. Therefore, the peptide bonded form is thought to enhance the availability of the glutamine in the bloodstream, making it more readily available to muscle tissue.
Glutamine peptides are bonded to other amino acids with peptide bonds, making them more stable and better utilized by the body. A product that combines both ensures better uptake, absorption, and stability and allows for better transport into the blood stream and muscle tissue.
It is acknowledged, however, that both forms help protect against the side effects of cancer treatments. Hospital stays have been reduced by those who have undergone major abdominal surgeries and were given glutamine supplements. Since the immune system relies heavily on glutamine, overall immune function appears to be better in hospital patients as evidenced by increased lymphocyte counts and the generation of neutrophils. Therefore, it may be a wise addition for everyone prone to many health problems.
Benefits
There are several benefits attributed to glutamine that science is discovering. Among the most important are its impact on the immune system and its ability to reduce alcohol and sugar craving sseverely. It is also proving to be a valuable supplement in protecting against the side effects of cancer therapies, impotence, fatigue, epilepsy, senility, and mental problems including depression and schizophrenia and mental retardation.
Glutamine is often a recommended treatment to improve mood, focus, concentration, memory, and to increase energy. It is often deficient in those with chronic yeast overgrowth: a depletion which is partially responsible for the “fuzzy thinking” described by these individuals.
Glutamine has been particularly successful in treating those with irritable bowel syndromes -- ulcerative colitis, celiac disease, ulcers, and leaky gut. Glutamine plays a key role in the metabolism, structure, and function of the entire gastrointestinal tract. It is the primary energy source for the cells that line the intestines and is essential in keeping the digestive tract healthy and functioning properly.
In Europe, glutamine is routinely given to hospital patients to increase their healing process and immune systems while reducing their hospital stays. In North America, glutamine peptides in TPN solutions have proven beneficial in patients with varying forms of catabolic stress including cancer, transplantation, intensive-care, surgical and the immune-suppressed. Oral glutamine supplementation has also been successfully used in very low birth-weight infants.
Studies have also been undertaken using Glutamine for sickle cell disease
Glutamine-rich Foods include: beef, fish, poultry, eggs, and dairy. Glutamine deficiency is rare even in vegetarians because glutamine can be found in such foods as legumes, hemp seeds, chia seeds, and raw cabbage and beets. Small amounts are found in freshly made vegetable juices and in such fermented foods as miso and good-quality yogurts.
Note: Taking Glutamine supplements with food inhibits aborption.
Digestion and Absorption
Following ingestion, Glutamine is absorbed from the lumen of the small intestine into the enterocytes. That which is not metabolized in the enterocytes is transported to the liver, where again, a little more is metabolized. Any Glutamine still not metabolized will enter the circulation system, where it is distributed to the various tissues of the body to assist in various metabolic activities. Doses up to 21 grams (in divided doses) daily appear to be well tolerated.
Caution: Those with kidney disease or severe liver failure should not take Glutamine.
Other names include: GLN; amino acid Q; amino acid Z; 2-amino-pentane-1,5- dioic acid-5-amide; 2-aminoglutaramic acid; levoglutamide; (S)-2; 5-diamino-5-oxopentaenoic acid; and glutamic acid 5-amide.
The terms L-glutamine and glutamine are used interchangeably.
Deficiency symptoms include: decreased IQ, convulsions, retardation, decreased coordination, mental fatigue, alcohol and sugar cravings, blood sugar instability, an overall decreased protein uptake leading to muscle wasting, chronic fatigue, poor memory, depression, stress intolerance, and gastrointestinal disorders.
Updated September 22, 2005.
