Effect of Coenzyme Q10 supplementation on antioxidant enzymes activity and oxidative stress of seminal plasma: a double-blind randomised clinical trial

Low seminal plasma concentrations of coenzyme Q10 (CoQ10) have been correlated with impaired sperm parameters, but the exact mechanism remains of dominating interest. This randomised, placebo-controlled study examined the effect of CoQ10 on catalase, superoxide dismutase (SOD) and F-2-isoprostanes in seminal plasma in infertile men and their relation with CoQ10 concentration. Sixty infertile men with idiopathic oligoasthenoteratozoospermia (OAT) were randomised to receive 200mg d(-1) of CoQ10 or placebo for 3months. 47 persons of them completed the study. Semen analysis, anthropometric measurements, diet and physical activity assessment were performed for subjects before and after treatment. Independent and paired t-test, chi-square test and ancova were compared outcomes of supplementation between two groups. CoQ10 levels increased from 44.74 +/- 36.47 to 68.17 +/- 42.41ng ml(-1) following supplementation in CoQ10 (P<0.001). CoQ10 group had higher catalase and SOD activity than the placebo group. There was a significant positive correlation between CoQ10 concentration and normal sperm morphology (P=0.037), catalase (P=0.041) and SOD (P<0.001). Significant difference was shown between the mean of changes in seminal plasma 8-isoprostane in two groups (P=0.003) after supplementation. Three-month supplementation with CoQ10 in OAT infertile men can attenuate oxidative stress in seminal plasma and improve semen parameters and antioxidant enzymes activity.