Effects of preduodenal ileal surgical transposition on enteroendocrine intestinal cells in wistar rats: Histomorphological and serum changes

Abstract

In our study, we focused on the role of the distal ileum as a main endocrine actor in relation to the pancreas. We investigated the effects of intestinally released hormones on the pancreas in terms of type 2 diabetes mellitus (T2DM) improvement, as a main effect of bariatric surgeries. To specifically study the importance of the ileum, we used an experimental surgical model performed in healthy Wistar rats. After preduodenal transposition of the ileum, we analyzed the histology and enterohormonal cells of the intestine. We measured the plasma level of several hormones and effectors in this enteropancreatic axis. We used a surgical control (Sham) group and a surgical group, where ileum preduodenal transposition (PDIT) was performed. We measured basal glycemia and serum levels of several incretins, including GLP-1, PYY, and GIP, and we performed a glucose overdose test. After two test periods, the basal glycemia and glucose overdose results were not different between groups, however, the PDIT group had significantly increased expression of GLP-1, with increased cellular release in the ileum and duodenum compared with the Sham group. Both plasma GIP levels and GIP tissue expression were decreased in the PDIT group compared with the sham group. There were no differences in PPY hormone levels. The ileum crypts and villi of the PDIT group showed improvement in histological parameters. We concluded that model animals had an altered transposed ileum related to the enterohormonal adaptation of the ileum. Our results indicated that the ileum is important in the hormonal control of the enteropancreatic axis.