SIRT1 and obesity due to melanocortin 4 receptor deficiency: Known to be increasingly expressed in exercise, PGC-1α is deeply implicated in mitochondria synthesis, and PGC-1α transgenic mice are reported to be not only less susceptible to obesity or diabetes but also associated with prolonged life expectancy.76 It has now been clarified that once activated by adiponectin/AdipoR1 signaling, AMPK phospholyrates PGC-1α at Thr177 and Ser538 and regulates PGC-1α by deacetylating PGC-1α via SIRT1.69