Background & Objective: Dexamethasone is a common medicine used for treatment of severe allergies and induces disturbance in the male reproductive system through inducing oxidative stress. Selenium as an antioxidant drug can suppress oxidative stress. The aim of this study was to evaluate the protective effects of selenium on the testis histological changes, spermatogenesis and daily sperm production in mice after treatment with dexamethasone. Material and Method: 24 Adult male NMRI mice (35±5gr) were divided randomly into 4 groups (n=6): control, Dexamethasone (i.p injection of 7mg/kg/day), Dexamethasone+ Selenium (i.p injection of 0.4mg /kg/day) and selenium), selenium. One day after the last injection, Body and testes weight were recorded and the left testis was fixed and used to estimate the daily production of sperm (DSP). In addition, Serum and tissue malondialdehyde (MDA) and serum testosterone levels were also analyzed. . Data were analyzed using one way ANOVA and the means were considered significantly different at P<0.05. Result: A significant decrease in the mean total volume of testis and mean volume of interstitial tissue, mean volume of seminiferous tubules (P<0.001), mean number of spermatocytes (p<0.002), round and long spermatids (p<0.001) and Leydig cells (P<0.017) were found in the dexamethasone group compared to the control group. The above parameters were increased in the Dexamethasone + Selenium group to the control level. Conclusion: These findings suggest that Selenium can have a protective role in the testes of mice against oxidative stress induced by dexamethasone.
