High dose of standardised extract of Costus afer leaves potentiates cadmium reproductive toxicity in Wistar rats.

Protective effects of standardised extract of Costus afer leaves (CAME), an extract with good antioxidants on cadmium-induced reproductive toxicity in male rats, were investigated in this study. Forty-two adult male Wistar rats were randomly divided into six groups and were treated every day regularly for 4 weeks. G1 (control) rats received 1 ml of vehicle treatment. G2 rats were intoxicated with 2.5 mg kg^-1 day^-1 s.c cadmium chloride for 1 week. G3 and G4 rats were intoxicated with cadmium as in G2 rats and were treated orally with 100 and 200 mg/kg bwt/day of CAME, respectively, for 4 weeks. Group G5 and G6 rats were orally treated with 100 and 200 mg kg^-1 day^-1 bwt of CAME, respectively, for 4 weeks. Significant changes (p < 0.05) in andrological parameters (sperm count, sperm morphology, serum testosterone and nitric oxide concentration) and testicular antioxidant parameters (reduced glutathione, lipid peroxidation and activities of catalase, glutathione S-transferase and glutathione peroxidase) caused by Cd toxicity were improved in cadmium-intoxicated rats treated with 100 mg/kg body weight of CAME. Administration of 200 mg/kg body weight of CAME to cadmium-intoxicated rats potentiated reproductive toxic effects of cadmium. In conclusion, lower dose of CAME is preferred over high dose in treatment of cadmium-induced reproductive toxicity in rats.