Addition of procyanidine to semen preserves progressive sperm motility up to three hours of incubation

Abstract

Several studies on semen physiology and sperm fertilizing capacity have shown a beneficial effect of antioxidants. Procyanidine is a natural antioxidant, more efficient compared with vitamin C and E, with many applications in the food, agriculture, pharmaceutical and cosmetic industry. Thus, we tested whether the addition of procyanidine to the semen of infertile men has a beneficial effect on spermatozoa during their in vitro incubation and during the cryopreservation process. Semen samples of 25 infertile men were divided in to two aliquots, in which procyanidine was added or not. Semen analysis, measurement of sperm DNA fragmentation index (DFI) and measurement of reactive oxygen species (ROS) were performed 3 h after incubation at 37 °C and after sperm cryopreservation and thawing. In-vitro addition of procyanidine to semen of infertile men resulted in a lesser decrease in progressive motility [-4 (-31:+6) vs. -6 (-31:+5), p < 0.001] and total motility [-5 (-29:+3) vs. -9 (-32:+2), p < 0.001] after 3 h of incubation compared with no addition of procyanidine. Sperm morphology was decreased only in the control group after 3 h of incubation [2 (0:+6) vs. 1 (0:+4), p = 0.009]. Furthermore, a larger increase in sperm DFI was observed in the control compared with the procyanidine group [9 (-7:+27) vs. 3 (-3:+18), p = 0.005] after thawing of cryopreserved semen samples. In conclusion, in-vitro addition of procyanidine to the semen of infertile men exerts a protective effect on progressive motility during handling and after 3 h of incubation as well as on sperm DFI during the process of cryopreservation.

Keywords: Antioxidants; Cryopreservation; DNA fragmentation index; Procyanidine; Semen analysis.