FGF21 and obesity due to melanocortin 4 receptor deficiency: Key search words were adipokines or their acronyms (adipocytes-fatty acid-binding protein (A-FABP or FABP4); chemerin (RARRES2 or TIG2); fibroblast growth factor-21 (FGF-21); lipocalin-2; omentin-1; vaspin); insulin resistance; inflammation; obesity; metabolic syndrome, cardiovascular disease; type II diabetes mellitus; non alcoholic fatty liver disease; articles in English and Spanish have been included in the analysis.