Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 51 1 2013 01 15 12 18 EN Hassan Ahmadvand Department of Biochemistry, Lorestan University of Medical Sciences, Khoramabad, Iran. Hiroshi Mabuchi Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Japan. Atsushi Nohara Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Japan. Junji Kobayahi Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Japan. Masa-aki Kawashiri Department of Lipidology, Graduate School of Medical Science, Kanazawa University, Japan. 2015 09 28  Coenzyme Q10, a lipid soluble benzoquinone, has excellent antioxidant and membrane stabilizing properties in the cardiac tissue. The present study investigated the effects of coenzyme Q10 on in vitro LDL oxidation quantitavely. The formation of conjugated dienes, malondialdehyde (MDA) and electrophoretic mobility were monitored as markers of the oxidation of LDL, respectively. Coenzyme Q₁₀ showed a decrease the formation of conjugated dienes and MDA, respectively, against oxidation in vitro. Coenzyme Q₁₀ also reduced electrophoretic mobility of the oxidized human LDL. Thus, results showed that the coenzyme Q10 exhibits strong antioxidant activity in CuSO₄-mediated oxidation of LDL (P<0.05) in vitro. The inhibitory effects of the coenzyme Q10 on LDL oxidation were dose-dependent at concentrations ranging from 20 nM to 300 nM. Moreover, the effects of coenzyme Q10 on LDL oxidation were compared with vitamin E and vitamin C. This study showed that coenzyme Q10 is a potent antioxidant to protect LDL against oxidation in vitro and may be a good alternative to reduce the risk of atherosclerosis and coronary heart disease and other free radical associated health problems. https://acta.tums.ac.ir/index.php/acta/article/view/4010 https://acta.tums.ac.ir/index.php/acta/article/download/4010/3985