IL6 and obesity due to melanocortin 4 receptor deficiency: In the vicious circle of obesity, the continuous expansion of white adipose tissue leads to an increase in the secretion of tumor necrosis factor α (TNF-α), C-reactive protein (CRP), interleukin-6 (IL-6), monocyte chemoattractant protein -1(MCP-1), and other pro-inflammatory cytokines, which eventually leads to a chronic inflammatory state [26,27,28,29].