In diet-induced obesity (DIO) mouse mode, FGF21 treatment inhibited the expression of hepatic sterol regulatory element-binding protein-1 (SREBP-1) gene and a wide array of genes involved in fatty acid and triglyceride synthesis, which was associated with the significant reduction in hepatic triglyceride levels [17]. This evidence concerns the gene FGF21 and obesity due to melanocortin 4 receptor deficiency.