As a prototypic inflammatory cytokine, TNF-α plays critical roles in various components of metabolic syndrome and substantial evidence links TNF-α with the impaired glucose tolerance and insulin resistance in individuals with obesity [10] and type 2 diabetes (T2D) [11,12], as well as in animal models of these two metabolic disorders [13]. This evidence concerns the gene TNF and obesity due to melanocortin 4 receptor deficiency.