ABSTRACT
Glutamine is the most abundant amino acid in the plasma and is involved in a large variety of metabolic and biochemical processes. In hypercatabolic conditions, low plasma glutamine levels have been reported and associated with a bad prognosis. Experimental data suggest that glutamine has anti-inflammatory properties in various cell types. In clinical studies performed in patients with acute pancreatitis, glutamine-supplemented parenteral nutrition decreased the inflammatory response, as showed by a decrease of Interleukin 8. The glutathione system is one of the major mechanisms protecting against oxidative stress in the cells. Glutamine may improve cellular immune response in critical illness. Several factors are involved in the regulation of gut barrier such as intestinal microbiota, mucus, tight junctions between epithelial cells, and intestinal immune system. In critically ill patients, glycemic control is an important issue and the use of intensive insulin therapy with tight glycemic control has been extensively debated.
