Mécanismes d’action potentiels de la glutamine chez le patient agressé

Several controlled studies and recent meta-analysis indicate that glutamine supplementation has beneficial effects on clinical outcome of critically ill and surgical patients. These effects could be explained in part by the role of glutamine as the preferential substrate of rapidly dividing cells but also by its influence on inflammatory and immune response, on oxidative stress, on heat shock protein expression and on glucose metabolism. Indeed, glutamine supports gut barrier function by stimulating gut protein synthesis and epithelial cell proliferation and by limiting apoptosis. In addition, glutamine enhances intestinal and systemic immune response and antioxidant defences such as glutathione pool. Glutamine also induces the expression of heat shock proteins that play a key role in cellular protection. In contrast, glutamine decreases intestinal and systemic inflammatory response by decreasing pro-inflammatory cytokine production but also by increasing anti-inflammatory cytokine production. This effect of glutamine on inflammatory response may be mainly related to its capacity to reduce NF-κB activity. More recently, some data indicate that glutamine may reduce insulin resistance and thus the risk of infectious complications.