The effects of Selenium on changes in sperm antioxidant capacity in old and adult rats

Selenium as an antioxidant is essential for normal function of testis and spermatogenesis. It can reduce formation of free oxygen radicals and as a result it is expected to improve male fertility. The aim of this study was to evaluate alterations in antioxidant capacity of old rats sperms after prescription of 0.2 mg/kg of Selenium.

In this study, 15 old male rats of 10-12 months of age and 15 adult male rats of 2-3 months of age were randomly divided into three groups: control, sham and experimental groups. Control group did not receive any treatment; sham group rats received intra peritoneal injections of equal volume of Selenium solvents (normal saline) as Selenium in experimental group. Experimental groups of male rats received daily intraperitoneal injection of Selenium (0.2 mg/kg) for 5 weeks. After 42 days from initiation of injection, the rats were killed by cervical dislocation and after obtaining sperm, total antioxidant capacity of the sperms was measured by FRAP assay. The absorbance of TPTZ-Fe+2 was read at 593 nm by spectrophotometery. For the statistical analysis, SPSS software was used and data analysis was performed by means of Kruskal-Wallis and Mann-Withney U tests. P<0.05 was considered significant.

Results of this study showed significant differences in mean values of total antioxidant capacity in both old and adult rats in experimental and control groups (P<0.05). Also comparison of mean values of antioxidant capacity of sperm solution in adult and old control groups showed a significant difference (742.26±1.06 vs. 672.061±0.78 respectively) (P<0.05).

The results of this study showed that Selenium treatment in old rats (0.2 mg/kg after 35 days) can improve total antioxidant capacity of the sperms of old rats. Regarding low levels of antioxidants in old rats, it can be suggested oxidative stress can result in diminution of antioxidant levels. Therefore antioxidant therapy could be considered as a method for improvement of the quality of sperms of old men.