LEP and obesity due to melanocortin 4 receptor deficiency: Further, as leptin resistance is often reported in obesity and T2DM (Maffei et al., 1995), enervate the regeneration of skeletal muscle in the ob/ob and db/db mouse models of obesity, also suggests that leptin deficiency or resistance could contribute to poor muscle regeneration and satellite cell function (Nguyen et al., 2011).