Combination of GLP-1 and sodium butyrate promote differentiation of pancreatic progenitor cells into insulin-producing cells.

We identified that nestin-EGFP-positive cells isolated by fluorescent-activated cell sorting (FACS) were downstream progenitor cells from colony-initiating pancreatic precursor cells. Under differentiation condition, these nestin-EGFP-positive cells could generate islet and neural cells. To investigate the conditions that allowed nestin-EGFP-positive progenitor cells (NPPCs) to efficaciously differentiate into insulin-producing cells in vitro, protocols were designed with glucagon-like peptide-1 (GLP-1) and the histone deacetylase inhibitor, sodium butyrate. We demonstrated that the combination of GLP-1 and sodium butyrate resulted in the increasing of levels of transcripts encoding pancreatic developmental factors and insulin. As a consequence, the amount of insulin-producing cells and insulin secretion were enhanced. These results indicated that NPPCs which were cultured in the presence of GLP-1 and sodium butyrate could specially differentiate into insulin-producing cells.