CCL2 and obesity due to melanocortin 4 receptor deficiency: Considering this chronic, localized, and low-grade inflammation, several pro-inflammatory cytokines are increased in individuals with obesity, including Tumor Necrosis Factor-alpha (TNF-α), Interleukin-6 (IL-6), Interleukin-7 (IL-7), Interleukin-8 (IL-8), Interleukin-1 (IL-1), monocyte chemoattractant protein-1 (MCP-1), and plasminogen activator inhibitor-1 (PAI-1).