Throughout the development of obesity, the release of adipokines with pro-inflammatory activities (leptin, resistin, IL-1, IL-6, IL-8, TNF-a) and the downregulation of anti-inflammatory ones (adiponectin, IL-10) establish a chronic state of inflammation, stimulated by NF-κΒ that predispose to metabolic morbidities (insulin resistance, type 2 diabetes and cardiovascular disorders) and cancer [43,44]. Here, RETN is linked to obesity due to melanocortin 4 receptor deficiency.