- Ken Takeda (Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Tokyo University of Science / Department of Hygiene Chemistry, Faculty of Pharmaceutical Science, Tokyo University of Science / email@example.com)
1) Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Tokyo University of Science , 2) Department of Hygiene Chemistry, Faculty of Pharmaceutical Science, Tokyo University of Science , 3) Biological Laboratory, University of the Air , 4) Department of Hygiene Chemistry, Ohu University School of Pharmaceutical Sciences
The in vivo nanotoxicity of nanoparticles is drawing increased attention as concerns grow over the biosafety of nanotechnology. TiO2 nanoparticles are coated to decrease the potential of harmful effects due to their photoactivity. Rutile-type alumina-coated titanium dioxide nanoparticles (Al2O3-TiO2-NPs) are frequently used in cosmetics to improve their dispersion stability. We herein discuss the effects of Al2O3-TiO2-NPs exposure during pregnancy on mouse spermatogenesis. Pregnant mice were injected five times, once each with 0.1 mL of sequentially diluted concentrations of a Al2O3-TiO2-NPs suspension (1, 10, 100 or 1,000 μg/mL) and received doses of 0.5, 5, 50 and 500 μg, respectively. Prior to injection, the size distribution of the Al2O3-TiO2-NPs was analyzed by dynamic light scattering (DLS) measurement. The average diameter was increased in dose-dependent manner from an average of 153.8 nm to 654.6 nm. The offspring testes were examined at 12 weeks postpartum. The agglomerates in the testicular sections were small (< 200 nm). They were confirmed by the characteristic peaks of the Ti and Al elements on field emission-scanning electron microscope/energy dispersive X-ray spectroscopy (FE-SEM/EDS). Low cellular adhesion and degenerated Sertoli cells were observed in the seminiferous epithelium of all of the Al2O3-TiO2-NP recipient groups by a histological analysis. The detrimental function of the Sertoli cells resulted in the formation of abnormal spermatozoa. The results suggested that Al2O3-TiO2-NPs that transferred from the mother’s body affected spermatogenesis in the offspring.