FGF21 and fatty liver disease: Based on preclinical data in hepatocytes, FGF21 is thought to affect hepatic steatosis by modulating AMPK phosphorylation to regulate lipid accumulation, reducing sterol regulatory element-binding transcription factor 1 (SREBF1) to inhibit lipid synthesis, increasing PPARα mRNA and PPARα translocation into the nucleus to impact fatty acid oxidation and promoting lipid transport and secretion of VLDL21.