TNF and obesity due to melanocortin 4 receptor deficiency: Especially, obesity increases the level of senescence-associated markers, such as senescence-associated β-galactosidase (SA-β-Gal) activity and the production of senescence-associated secretory phenotype (SASP), such as proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α); the level of these inflammatory cytokines accelerate the senescence of neighboring cells (Burton and Faragher, 2018).