Angiotensin II-induced overexpression of sirtuin 1 contributes to enhanced expression of Giα proteins and hyperproliferation of vascular smooth muscle cells

ANG II regulates various physiological functions including proliferation of VSMCs through the overexpression of Giα proteins. Sirt1, a class III histone deacetylase regulator, is implicated in several cellular functions, including VSMC growth and ANG II-induced hypertension. We showed for the first time that ANG II increased the expression of Sirt1, which through oxidative stress, growth factor receptor-mediated MAP kinase/Akt signaling pathway enhances the levels of Giα and cell cycle proteins resulting in the hyperproliferation of VSMCs.