P-240: Effect of Oxidative Stress on DNA Fragmentation Index in Sperm of Mature Mice

Background: One of the major factors affecting on male infertility is oxidative stress (OS). Two main sources of ROS production are leukocytes and spermatozoa. The ROS such as tertiary-butyl hydroperoxide (TBHP) may damage and fragmentate to sperm DNA, which can lead to complications in the offspring. In this study, we will investigate the effect of od on DNA fragmentation index (DFI) in sperm of mature Balb/C Mice. Materials and Methods: OS in adult mice testis was induced by injection of the 1:10 concentration of tertiary-butyl hydroperoxide. Adult male Balb/ mice were randomly selected. Case group included treated mice by TBHP for 2 weeks and control group treated only by Injection of DH2O. Induced ROS levels in testes tissue samples of all mice measured by flow-cytometry. Consequently, TUNNEL assay performed to detect sperm DNA damage using fluorescence microscopy. Results: According to flow-cytometry results, an increase in level of oxidative stress in ROS treated mice in comparison to control group was observed. Moreover, the level of DFI measured by fluorescence microscopy increased in TBHP treated mice compared with control mice (p≤0.05). Conclusion: As ROS is produced naturally in the body due to oxidative stress, it is likely that oxidative stress can cause DNA fragmentation in human-spermatozoa. Also, the balance between ROS production and antioxidant levels in the body can protect DNA against damages. This experiment shows that there is significant association between ROS and DNA fragmentation.