Cytotoxic Effects of Four Metallic Oxide Nanoparticles on Dorsal Root Ganglion (DRG) Neurons

S. Lu, A. Bhushan, S.W. Leung, C.K. Daniels, J.C.K. Lai
Idaho State University, US

Keywords: metallic oxide nanoparticles, dorsal root ganglion neurons, neurotoxicity of metallic oxide nanoparticles, cytoxicity of nanoparticles


Metallic oxide nanoparticles have diverse industrial applications because of their exploitable physico-chemical and other properties. Consequently, the occupational environmental exposure of humans to these nanparticles is increasing; however, the health impact of their exposure has not been fully assessed. We have systematically investigated the cytotoxicity of metallic and non-metallic oxide nanoparticles in mammalian neural and non-neural cell types. Because the putative cytotoxicity of nanoparticles of metallic and non-metallic oxides in peripheral nervous system neural cells is unknown, we have investigated the putative cytotoxic effects of nanoparticles of anatase TiO2, rutile TiO2, Fe2O3 and ZnO in dorsal root ganglion (DRG) neurons. Results of our studies revealed that the nanoparitcles investigated induced concentration- and time-related decreases in survival of DRG neurons. The rank order of the potency of the four types of metallic oxide nanoparticles in inducing decreases in survival of DRG neurons was: ZnO nanoparticles > anatase TiO2 nanoparticles > rutile TiO2 nanoparticles ≈ Fe2O3 nanoparticles. Our results also revealed that treatment with the four types of nanoparticles investigated exerted differential effects on the expression of p-AKT and p-ERK proteins – important cell survival/proliferation signals – in DRG neurons. Our findings may have pathophysiological implications in neurotoxicity of nanoparticles.