Attenuation of cryopreservation-induced oxidative stress by antioxidant: Impact of Coenzyme Q10 on the quality of post-thawed buck spermatozoa

The aim of this study was to determine the quality of post-thawed buck spermatozoa by attenuation of cryopreservation-induced oxidative stress using CoQ10, a lipophilic antioxidant. Ejaculates at every sampling period were collected from four Mahabadi bucks, pooled and diluted in soybean lecithin-based extenders containing 0 (negative control, NC), 0.5 (CQ0.05), 1 (CQ1), and 1.5 (CQ1.5) μM CoQ10 and 0.9% (v/v) DMSO (positive control, PC). The diluted semen was gradually cooled to 4 °C, then frozen and stored in liquid nitrogen. After thawing, total motility although was significantly higher in CQ1 (53.40 ± 1.83) than control groups (43.60 ± 1.83% and 42.20 ± 1.83%; P < 0.05), but this parameter did not differ between CQ1 and CQ1.5. Sperm viability was significantly higher in CQ1 (54.20 ± 2.03%) than that of control and CQ0.5. The CQ1 and CQ1.5 led to significantly higher the plasma membrane functionality compared to control groups. Sperm abnormality was significantly lower in CQ1 than that of NC. The results also showed that MDA level was significantly lower in CQ1 and CQ1.5 compared with control and CQ0.5. The CQ1 (59.43 ± 3.93%) was significantly increased mitochondrial activity compared to control groups. Although a greater value for %DFI was found in NC (10.24 ± 0.48%) and PC (9.77 ± 0.48%) groups compared to others, it was lower in CQ1 group (4.26 ± 0.48%). In conclusion, based on our research results, 1 μM CoQ10 could protect buck spermatozoa from cryoinjury.