LEP and fatty liver disease: In the non-pregnant state, metformin reverses fatty liver disease in obese leptin-deficient mice [21], blocks hepatic steatosis, liver inflammation, and fibrosis in a non-diabetic nonalcoholic steatohepatitis (NASH) mouse model [54], and counter-regulates diet-induced SREBP-1 and fatty acid synthase (FASN) protein expression in a mouse model [55].