The effects of mitochondria-targeted (MitoQ and Mito-TEMPO) and untargeted (SOD and CoQ10) antioxidants on ram's sperm quality and fertility potential during the cryopreservation process.

Sperm cryopreservation is a widely used procedure for storing donor semen prior to artificial insemination. However, spermatozoa experience biochemical and functional changes during cryopreservation. The current study aimed to compare the effects of mitochondrial-targeted (MitoQ and Mito-TEMPO) and untargeted (SOD and CoQ10) antioxidants on the quality traits of ram sperm and reproductive performance. Semen samples were collected and diluted in extenders as follows: the first group served as the control, while the other groups were supplemented with 100 U/mL superoxide dismutase (SOD), 1 μM CoQ10 (Q10), 50 and 100 nM MitoQ (MQ50 and MQ100), 50 and 100 μM Mito-TEMPO (MT50 and MT100), and 50 nM MitoQ+ 50 μM Mito-TEMPO (MQ/MT). After the freezing, sperm quality characteristics and fertility potential were evaluated. According to the current results, the groups MQ50, MQ100, MT50, MT100, and MQ/MT exhibited higher (P ≤ 0.05) rates of total motility (TM), progressive motility (PM), average path velocity (VAP), membrane integrity (MI), mitochondrial activity potential (MAP), acrosome integrity (AI), viable cells, and fertility potential, as well as lower (P ≤ 0.05) late apoptotic-like changes, DNA fragmentation, H2O2 concentration, and malondialdehyde (MDA) concentrations compared to the SOD and Q10 groups. Moreover, superoxide dismutase (SOD) concentration increased (P ≤ 0.05) in the groups of SOD, MT50, MT100, and MQ/MT than in other groups. Furthermore, the MQ/MT group exhibited the highest (P ≤ 0.05) rates of TM, PM, VAP, MI, MAP, AI, viable cells, and fertility potential, along with the lowest (P ≤ 0.05) late apoptotic-like changes, DNA fragmentation, H2O2 concentration, and MDA concentrations relative to the other groups. In conclusion, incorporating MitoQ+Mito-TEMPO into the extender during the semen freezing could be a valuable strategy to enhance the success of ram frozen semen.