Glutamine
Glutamine is the most prevalent amino acid in the human body, found in most proteins and classified as a nonessential amino acid because the body typically produces sufficient amounts. However, under stress conditions such as injury, burns, or intense exercise, the body may require additional glutamine, making it conditionally essential. It plays a critical role in various bodily functions, particularly as a primary energy source for the gastrointestinal tract, which is vital for maintaining the integrity of the intestinal lining and supporting immune function.
Glutamine is often utilized in clinical settings, available in forms such as oral capsules, powders, and intravenous solutions. It has been studied for its potential benefits in cancer therapy, where it may alleviate side effects from chemotherapy and radiation, such as gastrointestinal ulcers and nerve damage. Despite concerns that supplementation could fuel tumor growth, research suggests it may actually enhance immune function and improve recovery during cancer treatments.
While glutamine is generally well-tolerated, potential side effects may include gastrointestinal discomfort like constipation and bloating. As research continues, the role of glutamine in cancer treatment and overall health remains an area of active investigation, with ongoing studies aimed at understanding its complex relationship with both healthy and cancerous cells.
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Glutamine
DEFINITION: Glutamine is the most abundant amino acid in the body and is found in most proteins. Glutamine is considered a nonessential amino acid, since the body can normally synthesize an adequate amount for its needs.
Cancers treated or prevented: All cancers currently treated with chemotherapy or radiation
Delivery routes: Glutamine can be taken orally in capsules, powder, or tablets. In the clinical setting, it can be part of an enteral liquid formula given through a feeding tube through the nose, stomach, or small intestine. Glutamine can also be given intravenously.
How this compound works: Although glutamine is found largely as a component of proteins (skeletal muscle in particular), it serves various functions in the body. Stress conditions such as injury, burns, critical illness, or high-intensity exercise cause a greatly increased need for glutamine. Glutamine is considered a conditionally essential amino acid under these stress conditions, since dietary supplementation of glutamine is necessary. The gastrointestinal tract is the largest user of glutamine, particularly as a source of energy. Glutamine is important in wound healing and helps to mobilize components of the immune system. It also helps maintain the integrity of the intestinal lining to prevent bacteria and fungi entry.
Cancer cells have a great demand for glutamine as an energy source; this can deplete glutamine stores in muscle and other body tissues. Laboratory studies indicate that glutamine is necessary for the functioning of T lymphocytes and natural killer cells, which are components of the immune system. The depletion of body glutamine, therefore, could compromise the immune system's role in protecting against cancer. Some researchers were concerned about supplementing cancer patients with glutamine, thinking that supplementation could increase tumor growth. Such supplementation has been found, however, to increase glutamine stores in the body and improve intestinal and immune function.
In addition, studies have indicated that glutamine may alleviate the side effects of chemotherapy and radiation therapy. Glutamine supplementation has resulted in decreased intestinal mucosa ulceration and mouth inflammation. Peripheral neuropathy (numbness in extremities, motor weakness) often limits chemotherapeutic dosages. Glutamine may reduce neurological disorders' severity, permitting more effective dosages. Researchers believe that glutamine may work by restoring cellular levels of glutathione, a molecule that contains a sulfur group that binds to drugs and carcinogens. Glutamine supplementation increases the glutathione level in the body, helping to reduce toxic drug levels. Glutamine supplementation has been shown to increase the accumulation of the chemotherapeutic drug methotrexate inside tumor cells, increasing its killing effect.
In the mid-2020s, studies on glutamine and cancer remained conflicting and complex. Both healthy cells and cancerous cells relied on glutamine to grow and spread. Research continued to show that cancer cells use glutamine to proliferate. However, this happens even in environments with low glutamine levels. Scientists believe some cancer cells have adapted to steal glutamine from surrounding cells or have obtained the ability to make glutamine from glucose. Cancer cells use their excess glutamine to inhibit cellular repair. Due to these findings, medical researchers have concentrated their research on understanding cancer cells' dependence on glutamine. Although one would assume glutamine supplementation should, therefore, be avoided, it can be an integral adjunct therapy to conventional cancer treatments like chemotherapy and radiation. No research can say glutamine supplementation increases or prevents cancer.
Side effects: Since glutamine is so abundant in the body, even doses of up to 21 grams daily are well-tolerated. Side effects are mainly gastrointestinal and include constipation and bloating.
Bibliography
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