Effects of CeO2 Nanoparticles on the Viabilities of Neural PC12 and SH-SY5 Y Cells

OBJECTIVE:To investigate the effects of cerium oxide (CeO2) nanoparticles on the viabilities of nerve cells PC12 and SH-SY5Y.METHODS:CeO2 nanoparticles were synthesized, structures were characterized and properties were evaluated. PC12 cells and SH-SY5Y cells were treated with CeO2 nanoparticles at different concentrations (1, 2.5, 5, 10, 25, 50, 75, 100, 150 μg/ml) for 24 h and the cell viability was measured by MTT assay. Then PC12 cells and SH-SY5Y cells were co-treated with CeO2 and active oxygen scavenger NAC and the cells were stained with DCFH-DA probe for ROS. The number of cells and the fluorescence intensity were observed under a fluorescent inverted microscope. Differences were assessed by one-way ANOVA.RESULTS:After treatment with CeO2 nanoparticles, the viabilities of both PC12 cells (P＜0.01) and SH-SY5Y cells (P＜0.01) were decreased comparing with the control group. After staining with DCFH-DA probe, the fluorescence intensity of the nerve cells was enhanced depending on the concentration of CeO2 nanoparticles suggesting that CeO2 induced the generation of reactive oxygen species (ROS). The fluorescence intensity of PC12 cells was decreased after CeO2 nanoparticles (100 μg/ml) co-treatment with active oxygen scavenger NAC. Compared with CeO2 nanoparticles alone at 25 μg/ml (P＜0.01), 50 μg/ml (P＜0.01), 75 μg/ml (P＜0.01), 100 μg/ml (P＜0.01), the cell viability was significantly increased after co-treatment with NAC.CONCLUSION:CeO2 nanoparticles has a negative effect on the viabilities of nerve cells PC12 and SH-SY5Y, and the effect might be depend on ROS.