LEP and obesity due to melanocortin 4 receptor deficiency: With aging, there is a concomitant increase in the levels of serum leptin, proinflammatory cytokines [3, 7, 16, 17, 18] that are linked to obesity [1, 19], and the prevalence of metabolic diseases [1, 14, 20, 21, 22, 23, 24].