Glutamine Enriched Total Parenteral Nutrition Improves Splenocyte Interferon-Gamma Production

Background: Standard total parenteral nutrition (STD-TPN) may diminish host immunity as compared with enteral nutrition. Alanyl-Glutamine enriched TPN (Ala-Gln-TPN) has been suggested to restore immune defects caused by STD-TPN. This study is to investigate the effects of Ala-Gln-TPN on tumor necrosis factor (TNF) and interferon-gamma (IFN-gamma) production by splenocyte in vitro.Method: Rats were randomly divided into two groups as STD-TPN and Ala-Gln-TPN groups. They received isocaloric (199 kcal/kg/day) and isonitrogenous (Nitrogen: 2.2 gN/kg/day) nutrients for seven days, and were then sacrificed. Ala-Gln-TPN contained 30% (w/w) of amino acid as glutamine. Twenty-four-hour culture of splenocytes (SC) with Gin at the concentration of 0, 500, and 1000 mu M were performed in vitro. Supernatants were them collected for the measurement of TNF and IFN-gamma.Results: IFN production by SC in vitro in the medium with 500 mu M and 1000 mu M of Gln were significantly greater in the Ala-Gln-TPN group than those in the STD-TPN group. However, TNF production by SC in vitro did not different significantly between the two groups.Conclusion: Ala-Gln-TPN may improve host immunity by enhancing IFN production from splenocytes. (C) 2000 Elsevier Science Inc.