TNF and obesity due to melanocortin 4 receptor deficiency: In animal models used in experimentation, Hunsche et al. (5) observed that macrophage and lymphocyte chemotaxis, macrophage phagocytosis, NK cell activity, lymphocyte proliferative response, secretion of IL-1β, TNF-α, IL-6, IL-2 and IL- 10 in leukocyte cultures, as well as the antioxidant and oxidative capacity of obese adult rats were significantly impaired when compared to non-obese adult rats and similar to elderly rats, thus concluding that obesity can generate premature immunosenescence that is aggravated as the obese adult rat ages.