J.C.K. Lai, A.R. Jaiswal, V.K. Idikuda, J. Pfau, A. Bhushan, S.W. Leung
Idaho State University College of Pharmacy, United States
pp. 60 - 63
Keywords: silicon dioxide nanoparticles, nanotoxicology, Schwann cells, dorsal root ganglion neurons, oxidative stress, cell death
Silicon dioxide (SiO2) particles, including nanoparticles, have been increasing employed in diverse industrial and biomedical applications including those in drug formulations, food, and cosmetics as SiO2 has been generally regarded as a non-toxic substance. However, the environmental safety and health impact of SiO2 particles have not been elucidated. This study investigated the hypothesis that SiO2 nanoparticles exert differential cytotoxic effects on DRG neurons and Schwann cells. Treatment with SiO2 nanoparticles induced dose-related decreases in survival of DRG neurons and Schwann cells with Schwann cells being more susceptible. SiO2 nanoparticles induced concentration-related decreases in glutathione (GSH) in Schwann cells and such decreases were related to their decreases in survival. SiO2 nanoparticles also induced modest decreases in GSH in DRG neurons. Expression of manganese superoxide dismutase (Mn-SOD) in Schwann cells also showed concentration-related decreases when treated with SiO2 nanoparticles. However, expression of Mn-SOD in DRG neurons was increased. Thus, our findings may have pathophysiological implications in the biocompatibility and health hazard of SiO2 nanoparticles and may be critically relevant to toxicological studies prior to clinical trials of drugs formulated with and/or delivered employing agents containing such nanoparticles.