SIRT1 and endothelial dysfunction: SIRT1 levels and activity are reduced and SIRT1 protein degradation is accelerated in human lung epithelial cells under oxidative/carbonyl stress (15); these results contribute to the diminished ability of SIRT1 to acetylate p53, p65/RelA, and FOXO3, which causes inflammation, senescence, apoptosis, and endothelial dysfunction (13).