SIRT1 regulates metabolic functions centrally through the hypothalamus. This figure indicates major regions in the mouse hypothalamus that are influenced by SIRT1: dorsomedial hypothalamus (DMH), ventromedial hypothalamus (VMH), lateral hypothalamus (LH), arcuate nucleus (ARC), agouti-related peptide producing neurons (AgRP), pro-opiomelanocortin neurons (POMC), and suprachiasmatic nucleus (SCN). High levels of SIRT1 in DMH and LH promote physical activity and increased body temperature [93]. In POMC neurons loss of SIRT1 causes susceptibility to diet-induced obesity [94]. In addition, SIRT1 regulates feeding and ghrelin response through the AgRP neurons and VMH to counter diabetes [95, 96, 97]. In the SCN, SIRT1 assures robust central circadian control by increasing the amplitude of the indicated machinery of the clock [99]. Proteins depicted in the SCN are: brain and muscle ARNT-like 1 (BMAL1), circadian locomotor output cycles kaput (CLOCK), period (PER), cryptochrome (CRY), nicotinamide phosphoribosyltransferase (NAMPT), and RAR-related orphan receptor α (RORα).