Compared with P+A- mice, P-/A- mice exhibited higher serum free fatty acids, suggesting a stronger adipose lipolysis, which may cause less obese and more severe fatty liver. Therefore, this observation is still in agreement with the notion that “fat flow” from adipose to liver contributes to hepatic steatosis. On the other hand, both P-/A- mice and P-/A+ mice exhibited identical less obesity and higher serum free fatty acids, but only P-/A- mice developed severe fatty liver, suggesting that CYP2A5 deficiency is essential for the severe fatty liver development. Thus, the interaction between CYP2A and PPARα has opposing effects: protecting against fatty liver but promoting obesity.
