MAPK3 and diabetes mellitus: Zhang et al. have shown that FGF21 alleviates DM-related cardiac apoptosis via activating the extracellular signal-regulated kinase 1/2 (ERK1/2)/mitogen-activated protein kinase 14 (p38 MAPK)/AMPK pathway in a mice model of type 1 DM (T1DM) (20).