IL6 and obesity due to melanocortin 4 receptor deficiency: The inflammatory microenvironment of adipose tissue during obesity is generated by an imbalance between anti-inflammatory and pro-inflammatory cytokines, decreasing the secretion of anti-inflammatory cytokines and increasing pro-inflammatory cytokines such as tumour necrosis factor α (TNF-α), IL-1β, interferon γ (IFN-γ) and IL-6, which leads the development of a chronic inflammatory disease [15].