TNF and obesity due to melanocortin 4 receptor deficiency: Obesity results in (i) hyperinsulinemia with an increase in IGF-1, (ii) an increase in leptin and a decrease in adiponectin, (iii) chronic inflammation via IL-6, TNF-α, PAI-1, and NF-κB, (iv) an increase in free fatty acids, and (v) oxidative stress including DNA damage10.