The role of gut in type 2 diabetes mellitus during whole body gamma irradiation in high-fat diet Wistar rats.

ABSTRACT

PURPOSE: The effects of a low rate (100 mGy/min) fractionated whole body gamma irradiation (FWBGI) at different doses were assessed using a real-time PCR technique on the expression of some target genes implicated in the development of type 2 diabetes mellitus in high-fat diet (HFD) Wistar rats. METHOD: HFD Wistar rats were exposed to different doses (12, 24 and 48 Gy) divided into 24 fractions (three times a week for two months), thus, the daily doses were 0.5, 1, 2 Gy, respectively. Total RNA was extracted and the expression of target genes was measured in the four intestinal segments (duodenum, jejunum, ileum and colon). RESULTS: The pre-diabetic state already induced by HFD was found to be improved by irradiation exposure. This irradiation effect occurs mainly via altered anti-diabetic gene expressions (mRNA and protein levels) of the incretin glucagon-like peptide-1 (GLP-1) overall bowel segments except the colon which has its own specific response to irradiation exposure by the induction of the insulin receptor substrate 4 (IRS-4) and the uncoupling protein 3 (UCP3). CONCLUSIONS: Results could be of great importance suggesting for the first time, a protective role for FWBGI on HFD animal models by increasing GLP-1 and UCP3 levels.