IL6 and obesity due to melanocortin 4 receptor deficiency: Again resembling the case of IL6 but also IL15, former studies by Netea [252] and Zorrilla et al. [253,254] showed that IL8 null mice developed mature onset obesity, irrespective of the diet fed and gender, not only due to hyperphagia and hypoactivity but also disturbances in peripheral nutrient metabolism.