SIRT1 and diabetes mellitus: In diabetes mellitus, autophagy instead of being induced by cellular stress and organelles dysfunction, is impaired due to alteration of nutrient sensing pathways like mammalian target of rapamycin (mTOR), Adenosin monophosphate-activated protein kinase (AMPK) and NAD− dependent histone deacetylase (Sirt1) (Tanaka et al. 2012).