Titanium dioxide (TiO2) nanoparticles induced apoptosis of splenocytes in adult male albino rat and the protective role of Milk thistle seeds extract

Titanium dioxide nanoparticles (TiO2 NPs) are used as a common additive in many kinds of foods, personal care, and other consumer products used by people everywhere. However the toxological concern of TiO2 NPs has been linked with its ability to generate free radicals. The protection and clearance of TiO2 NPs by natural products extracts are recent studies and need further investigations. This work was carried out to evaluate the possible protective role of Milk thistle seeds extract against TiO2 NPs toxicological effects in the spleen of male albino rat. Rats were intraperitoneally injected with 100 mg/kg and 150 mg/kg of TiO2 once daily for 2 weeks. Others rats were orally administrated with 300 mg/kg of Milk thistle seeds extract for 1 week before and 1 week after the treatment with TiO2 NPs. Histologically TiO2 NPs caused anarchic splenic architecture, vacuolar degeneration in splenic parenchyma, depletion of splenocytes and decrease in splenic follicle size, and spelencytes apoptosis. Immunohistochemically, rats interaperitonialy injected with TiO2 NPs exhibited increase in the percentage of Caspase-3+ apoptotic cells; the increase of the apoptotic cells was dose dependant. The treatment with Milk thistle extract ameliorates these abnormalities effects and improved the structure and appearance of the treated splenocytes. From the present study it could be concluded that TiO2 NPs is capable of inducing splenocytes apoptosis which would be the potential mechanism underlying the toxicity of TiO2 NPs. Milk thistle extract could help in the protection of spleen against the toxic effects of TiO2 NPs.