Maintaining gut integrity during parenteral nutrition of tumor-bearing rats: Effects of glucagon-like peptide 2

Maintaining tumor-bearing rats on total parenteral nutrition (TPN)for eight days significantly reduced mass, protein, and DNA in small intestine and c olon. Coinfusion of glucagon-like peptide 2 (GLP-2) significantly increased each of these variables in the duodenum, jejunum, and ileum, but not in th e colon. Histological analysis of tissue revealed normal mucosa thickness a nd villus height in the small intestine of GLP-2-treated rats, whereas nont reated rats maintained on TPN exhibited villus shortening and thinning of t he mucosa. Compared with TPN alone, no significant effects of GLP-2 were no ted on tumor growth, liver weight, or heart weight. Coinfusion of GLP-2 wit h TPN had no significant effect on TPN-associated immunosuppression, as mea sured by mitogen-induced proliferation of cultured splenocytes. Although tr anslocation of bacteria to the mesenteric lymph nodes appeared to be reduce d in GLP-2-treated vats, the difference between groups was not statisticall y significant. These results suggest that hormonal alterations may be more important than an absence of luminal nutrition in TPN-associated mucosa cha nges in tumor-bearing rats. Additionally, maintenance of gut integrity duri ng TPN does not appear to be a sufficient condition for the avoidance of th e negative sequelae associated with this route of supplemental nutrition.