Morin inhibits cell proliferation and fibronectin accumulation in rat glomerular mesangial cells cultured under high glucose condition

Morin, is a natural bioflavonoid isolated from Chinese herbs of the Moraceae family, has been reported to possess antidiabetic activity. However, the role of morin on glomerular mesangial cells (MCs) proliferation and extracellular matrix (ECM) accumulation in diabetic condition is still unclear. Therefore, in this study, we investigated the role of morin on cell proliferation and ECM accumulation in rat glomerular MCs cultured under high glucose (HG) condition. Our results showed that morin inhibited HG-induced MC proliferation, arrested HG-induced cell-cycle progression, reversed HG-inhibited expression of p21Waf1/Cip1 and p27Kip1. It also inhibited HG-induced ECM expression, ROS generation and NOX4 expression in MCs. Furthermore, morin suppressed HG-induced phosphorylation of p38 MAPK and JNK1/2 in MCs. These data suggest that morin inhibits HG-induced MC proliferation and ECM expression through suppressing the activation of p38 MAPK and JNK signaling pathways. Thus, morin may be useful for the prevention or treatment of diabetic nephropathy.