CCL2 and obesity due to melanocortin 4 receptor deficiency: In obesity, the secretion of multiple cytokines including IL-3, IL-7, IL-8, TNFα and chemokines including monocyte chemotactic protein-1 (MCP-1, also called Chemokine C-C motif ligand 2 (CCL2)), are upregulated [67,96,97].