Background: Ileal transposition (IT) can effectively resolve obesity and improve type 2 diabetes. IT is associated with increased glucagon-like peptide 1 secretion. The mechanisms mediating the effects of IT on obesity and diabetes remain undefined. Given the role of pro-opiomelanocortin neurons in energy balance, we sought to determine its potential role in these processes.
Methods: Twenty non-obese diabetic Goto-Kakizaki rats underwent either IT or sham operation. Various measures including food intake, body weight, fasting plasma glucose, glucagon-like peptide 1 level, activated pro-opiomelanocortin neuron number, and pro-opiomelanocortin mRNA expression were evaluated.
Results: The IT group demonstrated significantly improved plasma glucose homeostasis with increased glucagon-like peptide 1 secretion. The IT group ate less and demonstrated reduced body weight gain over time. These effects were also associated with increased central neuronal activity with increased pro-opiomelanocortin and derivative gene expression in the hypothalamus and increased protein expression in the pituitary gland.
Conclusions: More pro-opiomelanocortin neurons in the hypothalamus of diabetes rats were activated after ileal transposition. These data suggest a potential important role for pro-opiomelanocortin neurons in the resolution of diabetes after IT.