STAT3 and obesity due to melanocortin 4 receptor deficiency: Obesity disrupts the dynamic role of these cells in energy and immune homeostasis altering the adipokine signaling and leading to a chronic inflammatory status characterized by increased plasmatic levels of inflammatory cytokines such as IL-6 and TNFα [11,12] These factors may synergize to further increase their own concentrations by activating multiple signaling pathways such as STAT3 [13].