PPARA and steatosis: Mice with a homozygous knockout of PPARα (peroxisome proliferator activated receptor alpha), which is a member of the steroid/nuclear receptor superfamily and mediates the biological and toxicological effects of peroxisome proliferators, do not accumulate fat under normal feeding conditions but fail to up-regulate FA oxidation, and thus develop severe steatosis when fatty acid delivery to the liver is increased by fasting [87].