SIRT1 and endothelial dysfunction: We hypothesized that cilostazol prevents endothelial dysfunction in vascular ECs and enhances angiogenesis by upregulating adiponectin secretion from SMCs, and to test this we investigated the effects of cilostazol on angiogenesis in vitro and in vivo through adiponectin/adipoRs and the SIRT1/AMPK signaling pathway.