RARRES2 and obesity due to melanocortin 4 receptor deficiency: Data obtained in humans have revealed alterations in chemerin levels in different states such as inflammatory diseases (psoriasis, arthritis, inflammatory bowel disease) or in patients with obesity, type 2 diabetes, and/or metabolic syndrome compared with lean and healthy subjects [20,30,40,41], hence, the relevance of gaining further insight on our understanding of the mechanisms regulating adipose tissue levels of both the ligand and the receptor in relation to food intake and adiposity.