DNA methylation regulates pancreatic gene expression and links maternal high-fat diet to the offspring glucose metabolism.

Maternal high-fat diet (HFD) is related to an increased risk of glucose metabolism disorders throughout the whole life of offspring. The pancreas is a glucose homeostasis regulator. Accumulating evidence has revealed that maternal HFD affects offspring pancreas structure and function. However, the potential mechanism remains unclear. In this study, the mouse dam was fed with HFD or control diet (CD) during prepregnancy, pregnancy and lactation. The pancreatic insulin secretion function and islet genome methylome of offspring were analyzed. Pancreatic islet specific gene methylation was detected by using MeDIP qPCR. The results showed that body weight, blood glucose after oral glucose loads, fasting serum insulin, and HOMA-IR index values were significantly higher in male 12-week-old offspring from HFD dams than in the offspring from CD dams. Maternal HFD induced insulin secretion defects in male offspring. Compared with that in maternal CD group, methylation of the Abcc8 and Kcnj11 genes was increased in maternal HFD group in male offspring pancreatic islets. Furthermore, the expression levels of Abcc8 and Kcnj11 were downregulated by intrauterine exposure to a maternal HFD. In summary, maternal HFD results in a long-term functional disorder of the pancreas that is involved in insulin secretion-related gene DNA hypermethylation.