Once activated, PPARα would bind to the DNA-bonding site of the down-stream genes in the form of PPAR-RXR heterodimer, thus regulate key fatty acid oxidation enzymes, such as ACOX1, CPT-I, CPT-II, etc.(30) The synthetic PPARα agonists are widely used in clinical to lower plasma lipid and improve fatty liver.(31) While ablation of PPARα gene could increase susceptibility to NAFLD in high fat-induced rats.(32) As shown in our study, the level of PPARα was lower in NAFLD rat liver, while soy isoflavone increased the protein expression of PPARα. This evidence concerns the gene ACOX1 and metabolic dysfunction-associated steatotic liver disease.