p13 overexpression in pancreatic β-cells ameliorates type 2 diabetes in high-fat-fed mice

•Expression of p13 was decreased in the pancreatic islets of high-fat-fed mice.•p13-transgenic mice showed increased glucose-stimulated insulin secretion.•p13-transgenic mice showed increased islet area and mitotic insulin-positive cells.•Lipid peroxidation levels were attenuated in high-fat diet-fed p13-transgenic mice.•p13 is a novel pancreatic factor with multiple beneficial effects against diabetes.

We examined the pancreatic function of p13 encoded by 1110001J03Rik, whose expression is decreased in pancreatic islets in high-fat-fed diabetic mice, by generating transgenic mice overexpressing p13 (p13-Tg) in pancreatic β-cells. p13-Tg mice showed normal basal glucose metabolism; however, under high-fat feeding, these animals showed augmented glucose-induced first-phase and total insulin secretion, improved glucose disposal, greater islet area and increased mitotic insulin-positive cells. In addition, high-fat diet-induced 4-hydroxynonenal immunoreactivity, a reliable marker and causative agent of lipid peroxidative stress, was significantly decreased in p13-Tg mouse islets. These results indicate that p13 is a novel pancreatic factor exerting multiple beneficial effects against type 2 diabetes.