IL6 and obesity due to melanocortin 4 receptor deficiency: Obesity is accompanied by low-grade inflammation characterized by increased pro-inflammatory cytokines and adipokines, and release of interleukin-1β (IL-1β), interleukin-6 (IL-6), TNF-α, and leptin by white adipose tissue (WAT) cells or inflammatory cells infiltrating obese adipose tissue [17,18].