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

Background: Standard total parenteral nutrition (STD-TPN) may diminish host defense against infection. Glutamine (Gln) is suggested to enhance host im munity. This study investigated the effects of antecedent alanyl-glutamine enriched TPN (Ala-Gln-TPN) on host responses to intraperitoneal bacterial c hallenge compared with STD-TPN. Methods: 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 ki lled before (0 hour) challenge and at 2 and 6 hours after challenge. Bacter ial numbers in peritoneal lavage fluid (PLF), liver, spleen, and blood were determined. Tumor necrosis factor-alpha (TNF), interleukin (IL)-8, and int erferon-gamma (IFN) in plasma and PLF were measured. Hepatic TNF, splenic T NF, and splenic IFN levels were determined. Results: The numbers of E. coli in systemic blood at 2 hours after intraperitoneal bacterial challenge wer e significantly lower in the Ala-Gln-TPN than in STD-TPN group. E. coli num bers in blood significantly correlated with those in the liver. The Ala-Gln -TPN also resulted in significantly higher PLF and hepatic TNF levels, high er splenic IFN levels, and lower plasma IL-8 levels at 6 hours after challe nge compared with the STD-TPN. Conclusions: Antecedent Ala-Gln enriched TPN enhance local, systemic, and remote organ immune responses to intraperiton eal bacterial challenge. Ala-Gln-TPN may enhance host defense and be more b eneficial than standard TPN in sepsis.