Effects of growth hormone (rhGH) and glutamine supplemented parenteral nutrition on intestinal adaptation in short bowel rats.Clin Nutr. 2001 Apr; 20(2):159-66.CN
This study was performed to compare the effects of recombinant human growth hormone (rhGH), glutamine (Gln) and simultaneous treatment with rhGH and Gln in rats subjected to 75% intestinal resection and maintained with parenteral nutrition (PN) for 6 days. Morphological changes including mucosal thickness, villus height, crypt depths and villus surface area of the residue jejunum were measured under a light microscope; expression of PCNA as an index of cell proliferation and apoptotic cells were observed using immunohistochemical staining; Ileal IGF-1 mRNA was determined by Northern blot analysis. The morphological parameters of the jejunal mucosa in rats treated with PN alone were only about 52-62% of those in reference group (P<0.01), this atrophy of the jejunal mucosa was accompanied by a 2.5-fold decrease in absolute counts of PCNA and a 10-fold increase in apoptotic index (P<0.01), IGF-1 mRNA transcript in residue ileum was decreased significantly (P<0.01). However, with rhGH or Gln, the mucosal architecture was improved significantly and was further improved when rhGH and Gln were given together, the morphological values in rats treated with Gln+rhGH was 79% higher than those with PN alone, and was associated with a 2-fold increase in PCNA counts and a 4-fold decrease in apoptotic index (P<0.01), IGF-1 mRNA expression was 78% higher than those with PN alone (P<0.01). We conclude that rhGH and Gln have synergistic effects on adaptation of the intestinal remnant in parenterally fed, short-bowel rats. The underlying mechanisms are associated with increased proliferation and decreased apoptosis in the intestinal epithelial cells. Local intestinal production of IGF-1 plays an important role in adaptation of the small intestine. Our findings support the concept that specific gut-trophic nutrients and growth factors may be combined to enhance the intestinal adaptation.