LEP and obesity due to melanocortin 4 receptor deficiency: In pathological obesity, adipose tissue undergoes a process called “adipose tissue regeneration,” which is characterized by increased levels of immune cell infiltration including interleukin‐6 (IL‐6), tumor necrosis factor‐alpha (TNF‐α), and leptin and eventually causes chronic low‐grade inflammation (Sun et al., 2011).