What is Glutamine?
Glutamine is one of the 20 amino acids. These are building blocks for proteins. While it is not recognized as an essential amino acid (it is abundant in the body, and therefore does not need to be consumed), it is sometimes referred to as a conditionally-essential amino acid for certain situations.
Abundant evidence suggests that glutamine may become a “conditionally essential” amino acid during certain circumstances. During stress (e.g. surgery) the body’s requirements for glutamine appear to exceed the individual’s ability to produce sufficient amounts of this amino acid and supplementation is desired.
How Does Glutamine Aid The Surgical Healing Process?
Glutamine has an important role in the immune response (more specific; cell-mediated immunity and in maintaining the integrity of the intestinal mucosa (the gut barrier). Glutamine is also a precursor to the production of the amino acid arginine and helps lower insulin resistance. In general, glutamine supplementation:
- reduces rates of infection,
- reduces inflammation,
- reduces length of hospital stay,
- reduces mortality,
- improves gut barrier function,
- improves immune function,
- improves immunological response in critically ill patients (Kim, Hyeyoung, 2011, November 1).
Glutamine as an Immunonutrient
“The concept of immunonutrition assumes that certain nutrients are able to positively affect a cell’s immune responses in a clinically meaningful way, thereby reducing infection-rates, countering oxidative stress in a healing wound, and improving the gut-barrier function to counter bacterial translocation.” (Calder, Philip C., 2007)
Surgery, trauma, burns and injury can induce excessively damaging inflammatory response (hyperinflamation) in some patients. This hyperinflammation is usually followed by an immunosuppressed state which increases a patient’s susceptibility to infection—resulting in significantly increased morbidity/mortality rates.
However, a range of nutrients exist which are able to modulate inflammation, its associated oxidative stress, and to maintain or improve immune function during the healing process. These so-called “immunonutrients” include several amino acids (including glutamine), antioxidant vitamins and minerals, long-chain n-3 fatty acids, and nucleotides.
Being the most abundant amino acid in human blood, intramuscular and plasma glutamine concentrations decrease post-surgery, and in cases where there is sepsis, cancer, burns, or post-operative fatigue.
Immunonutrient therapy that includes glutamine helps restore this to increase resistance to infectious pathogens and improve gut and intestinal immune tissue weight and cellularity (Calder, Philip C., 2007). Therefore, post-surgery, glutamine needs to be restored in the body, and it becomes a conditionally-essential amino acid; necessitating supplementation in specific amounts above daily requirements during the healing process (Kim, Hyeyoung, 2011, November 1).
Glutamine has many physiological and immunological roles, which make it important during the healing phases, post surgery/injury. It provides fuel for rapidly dividing cells, and helps to maintain the gut-barrier function to prevent bacterial translocation. It is the precursor to the formation of gluthionone, an important antioxidant. Its role in helping to control oxidative stress is important in controlling inflammation during healing.
It also plays an important role in nitrogen transport within the body, and serves as a substrate for the kidneys to process ammonia. Glutamine stimulates nucleotide synthesis. It also induces the expression of heat-shock proteins, which are important for tissue protection after stress or injury.
Glutamine is the most common amino acid in human blood, and serves many functions, including:
● Protein synthesis
● Regulation of kidney-balance by producing ammonium
● Next to glucose in importance as a provider of for cellular energy
● A nitrogen donator for many anabolic processes; especially for synthesis of purines
● A carbon donator for refilling the citric acid cycle
● Transports ammonia in the blood stream
- One study conducted in the late 1990s included 28 patients (12 males, 16 females—age ranges 42-86 years) who were admitted for elective resection of the colon or rectum following cancer treatments. These people were randomly allocated to either a test group or a control group where immunonutrient therapy, including glutamine therapy, was administered intravenously.The study found that the group which received glutamine had their hospital stays shortened by an average of 6.2 days. The study concluded that glutamine-supplemented immunonutrition significantly improved survival, indicating that this supplementation was a beneficial therapeutic measure after trauma or sever illness (Morlion, B. J., et al., 1998).
- Another study reviewed six randomized blind trials where glutamine supplementation was administered intravenously to patients recovering from elective surgery or accidental injury. This study found that in patients undergoing elective surgery, intravenous glutamine supplementation improves nitrogen balance, helps correct the decreased glutamine concentrations in healing wounds, and enhances net protein synthesis; especially in skeletal muscles. There were also net reductions in the length of hospital stays (Wilmore, Douglas W. (2001, September 1).
Though the human body normally makes all of the glutamine it needs, after surgery or other trauma, glutamine production becomes suppressed. It then becomes important to supplement glutamine (along with other immunonutrients).
Glutamine is important to the relief of oxidative stress and helps strengthen immune response during healing. Studies have proven that glutamine supplementation reduces hospital stays and improves survivability in patients. This leads to faster healing and less scar formation. However, no supplementation should be administered without advice from your physician.
Click here for an overview of recommended supplements before and after surgery.
Is glutamine a conditionally essential amino acid? Lacy JM, Wilmore DW. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/2080048
Calder, Philip C. (2007). Immunonutrition in surgical and critically ill patients. British Journal of Nutrition 98, S133-S139. Retrieved from: http://journals.cambridge.org/abstract_S0007114507832909
Glutamine. (n.d.). In Wikipedia. Retrieved November 26, 2012, from:
Kim, Hyeyoung. (2011, November 1). Glutamine as an Immunonutrient. Yonsei Med J 52 (6), 892-7. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3220259/pdf/ymj-52-892.pdf
Morlion, B. J., et al. (1998). Total Parenteral Nutrition With Glutamine Dipeptide After Major Abdominal Surgery. Annals of Surgery 227 (2), 302–308. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1191250/pdf/annsurg00012-0164.pdf
Wilmore, Douglas W. (2001, September 1). The Effect of Glutamine Supplementation in Patients Following Elective Surgery and Accidental Injury. J. Nutr. 131 (9), 2543S-2549S. Retrieved from: http://jn.nutrition.org/content/131/9/2543S.full.pdf+html