Effect of Nigella sativa on dexamethasone-induced testicular toxicity in mice.

Objective: The aim of the current study was to assess the effects of Nigella sativa essential oil on testicular toxicity in mice induced by dexamethasone.

Materials and methods: Forty NMRI mice were randomly divided into four groups. The first group (Sham) received 1 ml per day of normal saline by intraperitoneal (i.p.) injection for 7 days. The second group (Control) received (i.p) injection of 5 mg/kg dexamethasone for 7 days. The third group (Dexa+ N.S 5 mg/kg) received dexamethasone (5 mg/kg) and gavaged 5 mg/kg N. sativa essential oil for 7 days. The fourth group (N.S 5 mg/kg) for 7 days was gavaged 5 mg/kg N. sativa. Histopathology of testis, spermatogenesis, and sperm fertility rate were assessed.

Results: The results of histopathology assessments showed that in the third group, all histopathology criteria were decreased compared to the second group. The number of seminiferous tubules that had abnormal spermatogenesis in Johnsen's score was slightly decreased in the third group compared to the second group. Furthermore, in the third group, embryo formation criteria were increased.

Conclusion: The data of this research demonstrate that N. sativa improves spermatogenesis defects and sperm fertility in mice treated with dexamethasone.