In different rodent models of obesity and diabetes, it has been demonstrated that hyperinsulinemia stimulates induction of new cholesterol synthesis, through sterol regulatory element-binding protein 2 (SREBP2) activation, low-density lipoprotein receptor (LDLR) up-regulation, and the shutdown of its conversion into bile acids, thus leading to the hepatic accumulation of free cholesterol. This evidence concerns the gene LDLR and obesity due to melanocortin 4 receptor deficiency.