Effect of parenteral glutamine supplementation combined with enteral nutrition on Hsp90 expression and Peyer's patch apoptosis in severely burned rats

摘要

ObjectivesThe aim of this study was to investigate the effects of parenteral glutamine (GLN) supplementation combined with enteral nutrition (EN) on heat shock protein (Hsp) 90 expression and Peyer's patch (PP) apoptosis in severely burned rats. MethodsMale Sprague-Dawley (SD) rats were randomly assigned to four groups: Sham burn?+?EN?+?GLN-free amino acid (AA; n?=?10), sham burn?+?EN?+?GLN (n?=?10), burn?+?EN?+?AA (n?=?10), and burn?+?EN?+?GLN (n?=?10). Two hours after a 30% total body surface area (TBSA), full-thickness scald burn injury on the back, burned rats in two of the experimental groups (burn?+?EN?+?AA and burn?+?EN?+?GLN groups) were fed with a conventional EN solution by oral gavage for 7?d. Simultaneously, rats in the burn?+?EN?+?GLN group were given 0.35?g GLN/kg body weight/d once via a tail vein injection for 7?d and rats in the burn?+?EN?+?AA group were administered isocaloric/isonitrogenous GLN-free amino acid solution (Tyrosine) for comparison. Rats in two sham burn control groups (sham burn?+?EN?+?AA and sham burn?+?EN?+?GLN groups) were treated in the same manner except for the burn injury. All rats in the four groups were given 175?kcal/kg body wt/d. There was isonitrogenous, isovolumic, and isocaloric intake among the four groups. At the end of the seventh day after completion of the nutritional program, all rats were anesthetized and samples were collected for further analysis. PP apoptosis was measured by terminal deoxyuridine nick-end labeling (TUNEL). The expression of Hsp90 in PPs was analyzed by western blotting. Caspase-3 activity of PPs was also assessed. Levels of proinflammatory cytokines of gut tissues were evaluated by enzyme-linked immunosorbent assay (ELISA). The intestinal immunoglobulin A (IgA) content was also determined by ELISA. ResultsThe results revealed that intestinal IgA content in rats of the burn?+?EN?+?GLN group were significantly increased compared with those in the burn?+?EN?+?AA group (P?