Obesity induces a switch from anti-inflammatory M2 ATM towards pro-inflammatory M1 ATM which secrete pro-inflammatory cytokines, such as TNF-α, IL-6, IL1-β, IL-12, IL-23, and leukocyte-attracting chemokines, such as IL-8, Rantes, MIP-1α and MIP-1β. This evidence concerns the gene IL23A and obesity due to melanocortin 4 receptor deficiency.