SIRT1 and atherosclerosis: Autophagy is necessary to remove necrotic and old macrophages, helping slow down atherosclerosis progression [27]. Lui et al. also demonstrated that resveratrol, an activator of SIRT1, protects endothelial cells by activating adenosine 5′-monophosphate-activated protein kinase (AMPK)-SIRT1-autophagy [27].