MC4R and Wilson disease: The liver weights and triglyceride content in WD-fed MC4R KO mice before and after treatment was similar (liver weight before: 6.52 ± 0.82, after: 6.56 ± 0.84 g; triglyceride content before: 116 ± 11, after: 105 ± 15 mg/g tissue), suggesting that hepatic steatosis had already been established before drug treatment by pre-feeding with WD for 13 weeks.