title: The protective role of ubiquinol-10 against formation of lipid hydroperoxides in human seminal fluid.
abstract: Defective sperm function in infertile men has been associated with increased lipid peroxidation and impaired function of antioxidant defenses in spermatozoa. Evidence strongly suggests that CoQ10, a lipid-soluble component of the respiratory chain acts, in its reduced form (ubiquinol), as a potent antioxidant in various biological systems, such as lipoproteins and membranes. In this study we assayed CoQ10 content in both the reduced and oxidized form (ubiquinol/ubiquinone), and hydroperoxide levels in seminal plasma and seminal fluid from 32 subjects with a history of infertility. Our results showed a significant correlation between ubiquinol content and sperm count (r = 0.62; P < 0.05) in seminal plasma. An inverse correlation between ubiquinol content and hydroperoxide levels both in seminal plasma and in seminal fluid (r = -0.56; P = 0.01) was found. Using multiple regression analysis we also found a strong correlation among sperm count, motility and ubiquinol-10 content (P < 0.01) in seminal fluid. An inverse correlation between ubiquinol/ubiquinone ratio and percentage of abnormal morphology was also observed in total fluid. These results suggest that ubiquinol-10 inhibits hydroperoxide formation in seminal fluid and in seminal plasma. Since peroxidation in sperm cells is an important factor affecting male infertility, ubiquinol could assume a diagnostic and/or a therapeutic role in these patients.
authors.affiliation: Institute of Biochemistry, University of Ancona Medical School, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Alleva
authors.forename: A
authors.initials: A
authors.lastname: Scararmucci
authors.forename: F
authors.initials: F
authors.lastname: Mantero
authors.forename: S
authors.initials: S
authors.lastname: Bompadre
authors.forename: L
authors.initials: L
authors.lastname: Leoni
authors.forename: G P
authors.initials: GP
authors.lastname: Littarru
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D003067:Coenzymes; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis / Q000378:metabolism*; D007248:Infertility, Male / Q000188:drug therapy / Q000378:metabolism*; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D012661:Semen / Q000187:drug effects* / Q000378:metabolism; D013094:Spermatozoa / Q000473:pathology; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000032:analysis / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D003067:Coenzymes; D017382:Reactive Oxygen Species; D014451:Ubiquinone; C026663:ubiquinol-10; D006861:Hydrogen Peroxide; C024989:coenzyme Q10