GLUTAMINE DIPEPTIDE-SUPPLEMENTED PARENTERAL-NUTRITION REVERSES GUT ATROPHY, DISACCHARIDASE ENZYME-ACTIVITY, AND ABSORPTION IN RATS

Background: Total parenteral nutrition (TPN) is associated with intest inal atrophy and dysfunction possibly attributed to the absence of the nonessential amino acid glutamine from commercially available TPN sol utions because of the instability of the monoamino acid during heat st erilization and storage. The use of stable dipeptides may overcome thi s problem. In this study we tested the hypothesis that glutamine dipep tide supplementation with alanyl-L-glutamine during TPN for 10 days wo uld reverse small bowel atrophy and TPN-induced dysfunction in rats. M ethods: A conventional TPN solution (250 kcal/kg bw) was compared with an isocaloric and isonitrogenous TPN supplemented with alanyl-L-gluta mine dipeptide. A food-fed control group was included (n = 6 each grou p). Jejunum mucosal architecture, absorption of water and glucose, and disaccharidase activity of maltase and alkaline phosphatase were eval uated. Results: TPN-induced villous atrophy, significantly reduced abs orption rate, and decreased activity of villous enzymes, compared with the TPN group, could be reversed by supplementation of glutamine dipe ptide alanyl-L-glutamine to parenteral nutrition solutions with no dif ference to the control group. Conclusions: Glutamine dipeptide-enriche d parenteral nutrition preserves mucosal structure and reversed atroph y-associated dysfunction.