CCL2 and obesity due to melanocortin 4 receptor deficiency: Moreover, obesity contributes to the enrichment of WAT-educated helper and cytotoxic T cells through the additional aggravation of inflammatory mechanisms by secreting matrix metalloproteinases, vascular endothelial growth factor (VEGF), TNF-α, IL-6, MCP-1, and IL-1β, therefore leading to an obesity-driven inflammatory state [43,76,86,87].