CAT and hepatocellular carcinoma: Our previous clinical intervention study have observed that the administration of coenzyme Q10 at a dose of 300 mg/day in patients with HCC could significantly increase the antioxidant enzymes activities of SOD by 67.3%, CAT by 42.6%, and GPx by 26.5% and reduce oxidative stress by 17.3% after 12 weeks of supplementation [31].