Background: We planned to evaluate the effects of thiol/disulfide homeostasis (TDH) on sperm parameters in varicocele patients in this study.
Methods: According to sperm concentration (< 15 x 106/mL) sperm morphology (< 4%) and progressive motility values (< 32%) in the semen analysis, patients were divided into four groups as oligozoospermia (OS, n = 27), oligoasthenozoospermia (OAS, n = 20), oligoteratozoospermia (OTS, n = 26), and oligoasthenoteratozoospermia (OATS, n = 19). Patients with varicocele diagnosis but no pathology in semen analysis were accepted as the control group (n = 25). Groups with impaired semen analysis results were compared to the control group.
Results: No difference was detected between OS, OAS, OTS, and OATS groups and the control group in demographical (age, BMI) and varicocele parameters (vein diameter, grade). A significant difference was observed in disulfide level, disulfide/native thiol, disulfide/total thiol rates among OS, OAS, OTS, OATS groups and the control group in the evaluation of TDH parameters. They were significantly higher in OATS group. In OS, OAS, OTS, and OATS groups, it was found that native thiol and total thiol levels were lower and disulfide level was higher than control group, and thiol/disulfide homeostasis shifted to the disulfide side. It was detected that when disulfide value increases 1 μmol/L, the morphology deteriorated 0.3% and sperm concentration (106/mL) decreased 0.74 and progressive motility decreased 0.68%.
Conclusions: The results of the present study suggest that patients with varicocele who have impaired sperm parameters have oxidative stress characterized by TDH slide towards disulfide side and inadequate antioxidant response identified by a lower level of native thiol compared to controls.