Effect of resveratrol on sperm motility in subjects affected by idiopathic asthenozoospermia: An in vitro study

Asthenozoospermia (AZS) is responsible for about 80 % of male infertility cases. Oxidative stress (OS) seems to be involved in cases of AZS otherwise termed "idiopathic," so antioxidant molecules have gained increasing interest in the treatment of infertility. In the present study, the in vitro effects of two different concentrations (12 and 30 µM) of resveratrol (RSV), a potent natural antioxidant, on sperm motility and OS counteragent of 154 subjects with AZS were evaluated. After 1 hour at 37 °C, the control group and the group treated with 12 µM of RSV showed a slight increase in progressive motility (PM) and a simultaneous decrease in non-progressive motility (NP). Conversely, the group treated with 30 µM of RSV showed a significant decrease in all motility parameters. Moreover, a significant decrease in Dichlorofluorescein (DCF) fluorescence intensity from controls (248.14 ± 111.16 a.u.) was observed both in group treated with 12 µM (152.47 ± 110.59 a.u., p < 0.0001) and 30 µM of RSV (128.06 ± 94.21 a.u., p < 0.0001). These findings support the hypothesis that excessive ROS reduction may lead to redox unbalance that could paradoxically worsen the seminal parameters of subjects with AZS when treated with excessive doses of antioxidants.