Evaluation of the anti-oxidant effect of ascorbic acid on apoptosis and proliferation of germinal epithelium cells of rat testis following malathion-induced toxicity

OBJECTIVE(S): The aim of this study was to determine the protective role of ascorbic acid on apoptosis and proliferation of spermatogonia and primary spermatocyte cells after malathion administration as an organophosphate pesticide in rat testis. MATERIALS AND METHODS: Thirty male Wistar rats were randomly divided into five groups of 6 rats each, including control (no intervention), sham (normal saline 0.09%), malathion (50 mg/kg), malathion plus ascorbic acid (50 mg/kg and 200 mg/kg, respectively), and ascorbic acid (200 mg/kg) groups. Malathion and ascorbic acid were administrated via intraperitoneal injection once per day and seven times per week. After 6 weeks, animals were sacrificed, and testis tissue was used for evaluation of apoptosis and proliferation of germinal epithelium cells using the TUNEL and PCNA staining techniques. RESULTS: The results of TUNEL staining showed that the numbers of apoptotic cells in spermatogonia and primary spermatocyte cells were significantly increased in the malathion 50 mg/kg group vs control group (P<0.001). Co-administration of malathion 50 mg/kg and ascorbic acid 200 mg/kg significantly decreased the apoptotic cells in both cell types in comparison with malathion 50 mg/kg group (P<0.001). The results of PCNA staining revealed that the proliferation of these cells was significantly decreased in malathion 50 mg/kg group vs control group (P<0.001), and malathion 50 mg/kg plus ascorbic acid 200 mg/kg administration increased the proliferation of cells compared with malathion 50 mg/kg group (P<0.001). CONCLUSION: The results provide evidence that ascorbic acid showed preventive effects on malathion-induced toxicity in male rat testis.