CREB is a regulatory target for the protein kinase Akt/PKB in the differentiation of pancreatic ductal cells into islet β-cells mediated by hepatocyte growth factor

We have previously reported that the PI3K/Akt signaling pathway is involved in hepatocyte growth factor (HGF)-induced differentiation of adult rat pancreatic ductal epithelial cells (PDECs) into islet β-cells in vitro. The transcription factor CREB is one of the downstream key effectors of the PI3K/Akt signaling pathway. Recent studies showing that CREB is required for the survival of certain cell types prompted us to examine whether CREB is a nuclear target for activation via the HGF-dependent Ser/Thr kinase Akt/PKB in the differentiation of pancreatic duct cell into islet β-cells. In this study, we first attempted to examine whether HGF modulates the Akt-dependent activation of target gene CREB and then investigated whether CREB activity affects the differentiation of HGF-induced PDECs. Finally, we studied the role of CREB in modulating the expression of transcription factors in PDECs during the differentiation of HGF-induced PDECs. Our results demonstrated that CREB is a regulatory target for the protein kinase Akt/PKB in the differentiation of pancreatic ductal cells into islet β-cells mediated by HGF.

Research highlights
► CREB is a regulatory target for the protein kinase Akt/PKB in pancreatic duct cells.
► Activation of the PI3K/AKT/CREB pathway plays a critical role in the HGF-mediated differentiation of pancreatic duct cells in vivo.
► CREB was causally linked to the expression of transcription factors during PDEC differentiation induced by HGF.