CCL2 and obesity due to melanocortin 4 receptor deficiency: IL-6, IL-8, IL-15, TNF-α, MCP-1 (CCL2) and other molecules, such as fibroblast growth factor 21, irisin, myonectin, and myostatin, are involved in obesity with insulin resistance or type 2 DM [10,11,12,13,14].