TNF and obesity due to melanocortin 4 receptor deficiency: Since the observation that obese adipose tissue shows increased expression of the proinflammatory cytokine TNF-α [9], extensive research efforts have been made regarding inflammation in metabolic tissues, trying to determine what primes the insulin resistance phenomenon, the consequences of obesity, how to improve the molecular knowledge of insulin activity attenuation mediated by obesity, and how it can be managed in order to improve patient quality of life.