INS and obesity due to melanocortin 4 receptor deficiency: Dysfunctional adipocytes in obesity-associated adiposopathy or “sick fat” lose their ability to buffer energy and become resistant to the anti-lipolytic effects of insulin, leading to lipid spillover into the circulation, increased lipid storage in visceral depots, and deposition in ectopic organs such as the liver and arteries [62, 63].