TNF and obesity due to melanocortin 4 receptor deficiency: Interestingly, several studies have examined whether inflammation can lead to obesity [45–47] and T2D [48–50] in mice, finding that inflammation drives the development of insulin resistance (potentially through the phosphorylation of insulin receptor 1 by a TNF-α mediated response [51]) and suggesting that particular intestinal microbial configurations can promote immune responses driving metabolic dysfunction [51].