Ameliorative Roles of Exogenous Testosterone on Nitrite Damaged Testes and Sperm Parameters

Abstract

Background: Nitrate (NO3) is a common food additive used as a colour fixation and preservative in meats and fish. Human dietary exposure to NO2 is mostly through the inter-conversion of NO3 from vegetables, cured meat products, fresh meat, fish, dairy products, eggs and water intake. This experiment was designed to investigate to what extent exogenous testosterone (T) ameliorates the destructive effects of nitrite (NO2) on rats’ testes and sperm parameters. Methods: Thirty-five adult male Wistar rats weighed between 100g – 111g was used for the experiment. Rats were divided into 7 groups, for each group n =5. Group A received distilled water, group B1 C1 and D1 received 0.04mg/kgbw, 0.06mg/kgbw and 0.08mg/kgbw of NO2 respectively in total volume of 1ml distilled water for 60 days. Groups B2, C2 and D2 also received 0.04mg/kgbw, 0.06mg/kgbw and 0.08mg/kgbw of NO2 respectively followed by intra-muscular injection of testosterone (Andriol Testocaps) at 5mg/kgbw, 7.5mg/kgbw and 10mg/kgbw respectively every other day for 3 weeks Results: The quality of testicular cells was implicated by oral administration of NO2; distorted or deformed seminiferous tubules with loss of germinal cells were evident. Meanwhile, the NO2/T -treated testes showed normal tubular structures with complete spermatogenesis except at high dose of 0.08mg which showed mild vacuolation and arrested spermatogenesis. Consequently, the sperm counts was reduced significantly (P>0.05) following increased NO2 concentrations. However, the sperm counts of NO2/T-treated testes were statistically increased (P< 0.05) at dose dependent manner. The number of motile sperms of the testes exposed to NO2 was decreased insignificantly, meanwhile, NO2/T-treated-testes were found to be increased insignificantly (P>0.05) . Conclusion: The reactive oxygen species triggered by NO2 generated testicular oxidative stress, spermato-genesis disruption and histological damages within the period of 60 days of ingestion. Meanwhile, these possible toxicological effects caused by NO2 could be effectively reversed using androgen hormone (testosterone) therapy within the period tested according to the present study.