ATG7 and obesity due to melanocortin 4 receptor deficiency: Interestingly, in obesity models, such as high-fat-diet-fed mice and the leptin-deficient ob/ob mice, it has been reported that chronic overnutrition decreases hepatic ATG7 levels and autophagy activity, being liver-specific ATG7 overexpression sufficient to prevent hepatic steatosis (Yang et al., 2010).