Mechanisms of Multi-walled Carbon Nanotubes-Induced Oxidative Stress and Genotoxicity in Mouse Fibroblast Cells

The extensive production and wide application of carbon nanotubes have made investigations of its toxic potentials necessary. In the present study, we explored the underlying mechanism through which multi-walled carbon nanotubes (MWCNTs) induce toxicity in mouse fibroblast cells (L929). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and neutral red uptake viability assays were used to examine mechanisms of cytotoxicity. Dose and time-dependent cytotoxicity was observed in L929 cells. The MWCNTs significantly increased the generation of reactive oxygen species, lipid peroxidation, superoxide dismutase, and decreased glutathione. It was observed that the MWCNTs induced caspase 3 activity. The highest DNA strand breakage was detected by comet assay at 300 mu g/mL of MWCNTs. Thus, the data indicate that MWCNTs induced cytotoxicity and apoptosis in L929 cells via oxidative stress.