Antioxidative efficacy of parallel and combined supplementation with coenzyme Q10 and d-α-Tocopherol in mildly hypercholesterolemic subjects: a randomized placebo-controlled clinical study
- 1 January 2000
- journal article
- research article
- Published by Taylor & Francis in Free Radical Research
- Vol. 33 (3) , 329-340
- https://doi.org/10.1080/10715760000301501
Abstract
It has been claimed that coenzyme Q10 (Q10) would be an effective plasma antioxidant since it can regenerate plasma vitamin E. To test separate effects and interaction between Q10 and vitamin E in the change of plasma concentrations and in the antioxidative efficiency, we carried out a double-masked, double-blind clinical trial in 40 subjects with mild hypercholesterolemia undergoing statin treatment. Subjects were randomly allocated to parallel groups to receive either Q10 (200 mg daily), d-α-tocopherol (700 mg daily), both antioxidants or placebo for 3 months. In addition we investigated the pharmacokinetics of Q10 in a separate one-week substudy. In the group that received both antioxidants, the increase in plasma Q10 concentration was attenuated. Only vitamin E supplementation increased significantly the oxidation resistance of isolated LDL. Simultaneous Q10 supplementation did not increase this antioxidative effect of vitamin E. Q10 supplementation increased and vitamin E decreased significantly the proportion of ubiquinol of total Q10, an indication of plasma redox status in vivo. The supplementations used did not affect the redox status of plasma ascorbic acid. In conclusion, only vitamin E has antioxidative efficiency at high radical flux ex vivo. Attenuation of the proportion of plasma ubiquinol of total Q10 in the vitamin E group may represent in vivo evidence of the Q10-based regeneration of the tocopheryl radicals. In addition, Q10 might attenuate plasma lipid peroxidation in vivo, since there was an increased proportion of plasma ubiquinol of total Q10.Keywords
This publication has 35 references indexed in Scilit:
- Effect of Oral Coenzyme Q10 Supplementation on the Oxidation Resistance of Human VLDL+LDL Fraction: Absorption and Antioxidative Properties of Oil and Granule-Based PreparationsFree Radical Biology & Medicine, 1997
- Effect of supplementation of smoking men with plain or slow release ascorbic acid on lipoprotein oxidationEuropean Journal of Clinical Nutrition, 1997
- Supplementation With Low Doses of Vitamin E Protects LDL From Lipid Peroxidation in Men and WomenArteriosclerosis, Thrombosis, and Vascular Biology, 1995
- The Effect of α-Tocopherol Supplementation on LDL OxidationArteriosclerosis, Thrombosis, and Vascular Biology, 1995
- Bioavailability of four oral Coenzyme Q10 formulations in healthy volunteersMolecular Aspects of Medicine, 1994
- Radical-mediated oxidation of isolated human very-low-density lipoprotein.Arteriosclerosis and Thrombosis: A Journal of Vascular Biology, 1994
- Low density lipoprotein oxidizability by copper correlates to its initial ubiquinol‐10 and polyunsaturated fatty acid contentFEBS Letters, 1994
- Evidence of Plasma CoQ10‐Lowering Effect by HMG‐CoA Reductase Inhibitors: A Double‐Blind, Placebo‐Controlled StudyThe Journal of Clinical Pharmacology, 1993
- Dietary supplementation with coenzyme Q10 results in increased levels of ubiquinol-10 within circulating lipoproteins and increased resistance of human low-density lipoprotein to the initiation of lipid peroxidationBiochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism, 1992
- Quantitative Estimation of Dehydroascorbic Acid and Ascorbic Acid by High-Performance Liquid Chromatography—Application to Human Milk, Plasma, and LeukocytesJournal of Liquid Chromatography, 1988