Alanyl-glutamine enriched total parenteral nutrition improves local, systemic, and remote organ responses to intraperitoneal bacterial challenge.

Abstract

Standard total parenteral nutrition (STD-TPN) may diminish host defense against infection. Glutamine (Gln) is suggested to enhance host immunity. This study investigated the effects of antecedent alanyl-glutamine enriched TPN (Ala-Gln-TPN) on host responses to intraperitoneal bacterial challenge compared with STD-TPN. Rats were divided into STD-TPN and Ala-Gln-TPN groups. They received isocaloric and isonitrogenous nutrition for 7 days and were challenged intraperitoneally with E. coli. Rats were killed before (0 hour) challenge and at 2 and 6 hours after challenge. Bacterial numbers in peritoneal lavage fluid (PLF), liver, spleen, and blood were determined. Tumor necrosis factor-alpha (TNF), interleukin (IL)-8, and interferon-gamma (IFN) in plasma and PLF were measured. Hepatic TNF, splenic TNF, and splenic IFN levels were determined. The numbers of E. coli in systemic blood at 2 hours after intraperitoneal bacterial challenge were significantly lower in the Ala-Gln-TPN than in STD-TPN group. E. coli numbers in blood significantly correlated with those in the liver. The Ala-Gln-TPN also resulted in significantly higher PLF and hepatic TNF levels, higher splenic IFN levels, and lower plasma IL-8 levels at 6 hours after challenge compared with the STD-TPN. Antecedent Ala-Gln enriched TPN enhance local, systemic, and remote organ immune responses to intraperitoneal bacterial challenge. Ala-Gln-TPN may enhance host defense and be more beneficial than standard TPN in sepsis.