Although it was initially suggested that the main source of TNFα in obesity were adipocytes, it is now well recognized that M1 macrophages infiltrated in adipose tissue are responsible for increased levels of this cytokine (Arkan et al., 2005; Solinas et al., 2007; Galic et al., 2010; Nakamura et al., 2014). Here, TNF is linked to obesity due to melanocortin 4 receptor deficiency.