Oxidative Stress Effect on the Spermatogenesis Genes Expression in the Mouse Model - Abstract
We aimed to evaluate the effects of oxidative stress induced by tertiary-butyl hydroperoxide on the DNA Fragmentation Index (DFI) and expression of spermatogenesis genes. Totally, 15 mice of BALB/c strain were categorized into 3 equal groups. To induce oxidative stress (OS), the case group was intraperitoneally injected with 1:10 (Lethal Dose) LD50 (100 ?l) of tert-butyl hydroperoxide (t-BHP) for 14 days. Sterile water (200?l) was
given intraperitoneally as a placebo in the control group. Whether OS is responsible for gene expression alteration, a third group of mice was treated simultaneously with t-BHP and Taurine for 14 days. In each group, the OS level was determined by the isolation of testicular cells and measurement of H2O2 and O2•- levels by flow cytometry. In order to evaluate the incidence of the DFI and apoptosis, tunnel assay was performed on prepared testis tissue samples. By the completion of the treatment phase, the mice were sacrificed and the expression of Dazl, Ddx3y, Smcy and Usp9y genes was measured by RT-PCR in each group. Flow cytometry indicated an increase in reactive oxygen species (ROS) in testicular cells following t-BHP treatment (p < 0.009) and a reduction after Taurine co-administration (p < 0.008). Also, the TUNEL assay showed an increase in DFI in sperm DNA following t-BHP treatment and a reduction after Taurine co-administration (p < 0.008). Our results showed that the ROS decrease (p<0.001) the expression of the mentioned genes and Taurine treatment adjacent to t-BHP significantly reduced the ROS level and protected against downregulation of the Dazl, Ddx3y, Smcy and Usp9y genes (p<0.001, p = 0.030, p = 0.002, p = 0.011 respectively). The oxidative stress may reduce the expression of these Y chromosome genes significantly that are involved in spermatogenesis, and the use of the antioxidant may be a protection against downregulation.