Cytotoxic and genotoxic effects of titanium dioxide nanoparticles in testicular cells of male wistar rat.

Serious concerns have been expressed about potential risks of engineered nanoparticles. Regulatory health risk assessment of such particles has become mandatory for the safe use in consumer products and medicines; also, the potential effects on reproduction and fertility are relevant for this risk evaluation. In the present study, we examined the effects of intravenously injected titanium dioxide nanoparticles (TiO2-NPs; 21 nm), with special emphasis on reproductive system. Antioxidant enzymes such as catalase, glutathione peroxidase, and superoxide dismutase showed a significant decrease, while significant increase in lipid peroxidase was observed. Our results confirmed the bioaccumulation of TiO2-NPs in testicular cells. In TiO2-NPs-treated animals, various functional and pathological disorders, such as reduced sperm count, increase in caspase-3 (a biomarker of apoptosis), creatine kinase activity, DNA damage, and cell apoptosis were observed. Moreover, the testosterone activity was decreased significantly in a dose-dependent manner in the animals treated with TiO2-NPs as compared with control group animals. It is concluded that TiO2-NPs induce oxidative stress, which produce cytotoxic and genotoxic changes in sperms which may affect the fertilizing potential of spermatozoa.