IL6 and obesity due to melanocortin 4 receptor deficiency: We now show that as previously reported [38], and similar to models of high-fat diet-induced obesity in mice, feeding a high-fat diet to APOE*3-Leiden.CETP mice induced inflammation in the gonadal white adipose tissue suggested by the increased expression of inflammatory cytokines interleukin-6 (Il6) and monocyte chemotactic protein-1 (MCP-1 or Ccl2) in animals fed a high-fat diet for 16 weeks compared to those fed a standard chow diet (Figure 2).