Among the SIRTs, SIRT3 is the major mitochondrial form that has relevance in supporting fatty acid oxidation, enhancing the antioxidant defense system, and repairing mitochondrial DNA damage, which implies that SIRT3 can be a new target for protection against lipotoxicity and obesity-induced metabolic complications [19]. This evidence concerns the gene SIRT3 and obesity due to melanocortin 4 receptor deficiency.