Influence of idebenone on ram semen quality stored at 4°C.

Abstract

The current study was designed to investigate the effect of idebenone (Id), an antioxidant on ram semen quality. Semen samples were collected, pooled and diluted in a Tris-based extender supplemented with 0, 1, 2, 4 and 8µM idebenone. Computer-assisted sperm analysis was used to evaluate spermatozoa kinematics. Sperm viability and membrane functionality were assessed respectively, by eosin-nigrosin staining and HOS test. Biochemical assays were carried out to measure different metabolites in spermatozoa and medium at 0, 24, 48 and 72hr. Total and forward progressive motility were greater in 1, 2 and 4µM idebenone treated groups compared to control at 24, 48 and 72hr time points (p<0.05). Semen supplementation with Id significantly increased viability and functionality of spermatozoa membrane during storage (p<0.05). Lower amounts of lipid hydroperoxides in medium and spermatozoa were observed in Id-treated groups compared to control one at 24 and 48hr of storage (p<0.05). Medium and spermatozoa amounts of malondialdehyde and nitric oxide were less in Id 4µM group compared to the control at 72hr (p<0.05). Total antioxidant capacity values and superoxide dismutase activity of spermatozoa and medium were greater in 2 and 4µM idebenone treated groups in comparison with the control at 72hr (p<0.05). Results of the current study indicated that ram semen supplementation with Id at 4µM level improved quality by ameliorating nitrosative and peroxidative stress, hence could be considered as an antioxidant additive during storage at 4°C.