FGF21 and metabolic dysfunction-associated steatotic liver disease: Overexpression of ATF6 in NAFLD livers leads to activation of the ATF6-PPARα axis, promoting an increase in hepatic FAO genes including fibroblast growth factor 21 (Fgf21), a liver-secreted cytokine that regulates hepatic metabolic processes, including fat oxidation, gluconeogenesis, and metabolic gene expression16.