Can Vanillic Acid, a Phenolic Substance, Be a Useful Tool to Prevent Oxidative Stress Induced by Freezing Ram Sperm?

The objective of the study was to investigate the vanillic acid's (VA) protective effects, a phenolic compound, on the ram semen after freeze-thaw. Semen was obtained from Ramlıç rams and was diluted with control (0 μg/mL VA) and VA-supplemented Tris-based extenders at concentrations of 1, 10 and 50 μg/mL. The diluted semen was equilibrated for 2 h at +4°C, filled into 0.25 mL straws and frozen in liquid nitrogen vapour. It was then stored in a liquid nitrogen container at -196°C. For analysis, the samples were thawed at 37°C for 30 s in a water bath. There was no difference detected among total and progressive motility as well as velocity parameters (p > 0.05) except for rapid progressive motility (p < 0.05). The findings support the idea that VA has an outstanding effect on reducing DNA damage (p < 0.001). While there was no positive development with regard to total oxidant status (p > 0.05), VA enhanced the antioxidant defences of total antioxidant status (p < 0.05). VA administered at doses of 10 and 50 μg increased total antioxidant status (p < 0.01). Lipid peroxidation was not directly affected by VA application (p > 0.05); otherwise, 10 and 50 μg VA treatments showed a positive effect on viability (p < 0.001). Based on findings, it was concluded that although VA was put in the semen extender, it did not have an ameliorative potency on sperm motility and velocity properties except for specific sub-parameters such as rapid progressive motility. All applied doses reduced DNA damage, and 10 and 50 μg doses supported cellular viability.