In obesity, white AT overgrowth leads to increased production of pro-inflammatory cytokines including TNF-α, interleukin-6 (IL-6), MCP-1 and inducible nitric oxide synthase (iNOS), activation of inflammatory pathways of IкB kinase (IKK-β) and nuclear factor-кB (NF-кB), mitochondrial dysfunction, reactive oxygen species (ROS) overproduction and depletion of the antioxidant defense(28). The gene discussed is NOS2; the disease is obesity due to melanocortin 4 receptor deficiency.