A molecular sign of obesity is represented by pro-inflammatory macrophages that infiltrate the adipose tissue, which further leads to a high production of pro-inflammatory cytokines (interleukins IL-6, IL-8, and 1L-1β or tumor necrosis factor α (TNF-α) and chemokines such as C-C motif chemokine ligand 2 (CCL-2) [172]. Here, CCL2 is linked to obesity due to melanocortin 4 receptor deficiency.