IL6 and obesity due to melanocortin 4 receptor deficiency: To investigate whether a deficient IL-6 signaling was established in skeletal muscle of subjects with obesity or type 2 diabetes, we measured the protein abundance of IL-6Rα in skeletal muscle biopsies from normal glucose tolerant (NGT) subjects and people with type 2 diabetes that were either non-obese or obese (DM) (Table 1).