Dose-dependent Cytotoxicity and Oxidative Stress Induced by "Naked" Fe_3O_4 Nanoparticles in Human Hepatocyte

The dose-dependent cytotoxicity effect on human hepatocyte(HL-7702 cells) induced by "naked" Fe3O4 nanoparticles was assessed through cell viabilities and lactate dehydrogenase(LDH) activities. Three important oxi dative indexes of the cells by glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) and malondialde hyde(MDA) were determined. The good correlation of the cell viabilities with their GSH-Px, SOD and MDA levels indicated that the cytotoxicity is related to activation of oxidative stress induced by Fe3O4 nanoparticles. The oxida tive stress also leads to corresponding DNA damage in a similar dose-dependent manner, followed by the changes of cell cycle and cell apoptosis. Such work provides important experimental data for the safety evaluation of superpa ramagnetic Fe3O4 nanoparticles.