Role of microRNAs in compensatory b-cell mass expansion associated with pregnancy and obesity

We found that in rodents, b-cell mass expansion during pregnancy and obesity is associated with changes in the expression of a group of islet microRNAs. We were able to reproduce in isolated pancreatic islets the decrease of miR-338-3p level observed in gestation and obesity by activating the G-protein coupled estrogen receptor GPR30 and the GLP1 receptor. Blockade of miR-338-3p in b-cells using specific anti-miR molecules mimicked gene expression changes occurring during b-cell mass expansion and resulted in increased proliferation and improved survival both in vitro and in vivo. These findings point to a major role for miR-338-3p in compensatory b-cell mass expansion occurring under different insulin resistance states. GSM880669 - GSM880674 3 biological replicate of INS832/13 cells treated with either a control or an antimiR338 were submitted to RaGene V1,0 affymetrix chip to decipher the role of miR338 GSM896009 - GSM896016 Islets from control (n=4) or 14 days pregnant female rat (n=4) were taken. Total RNA was extracted and microRNA profiling was performed with miRNA Agilent arrays.