| As a non-metal oxide, yttrium oxide (Y2O3) nanoparticles have numerous applications in chemical synthesis, mechanical polishing and as additives to drugs, cosmetics, varnishes and food. Recent data has suggested that these particles are capable of inducing oxidative stress and cytotoxicity in human endothelial cell lines. To examine the potential mechanisms of yttrium oxide toxicity, human embryonic kidney (HEK293) cells were exposed to 1, 5, 10, 50 and 100 muM of Y2O3 nanoparticles for 12, 24, 36 or 48 hr. We hypothesized that exposure of HEK293 kidney cells to Y 2O3 nanoparticles would be associated with increased evidence of intracellular oxidative stress and cell death. Our data suggested that exposure to Y2O3 nanoparticles was associated with a time and dose dependent decreases in cell viability and evidence of increased cellular superoxide levels. Immunoblotting of protein isolates demonstrated that changes in cell viability were associated with alterations in protein kinase B (Akt), Bax / Bcl-2 and caspase-3 expression. Taken together, these data suggest that Y2O3 nanoparticle exposure of similar size with different concentrations may be associated with diminished cell viability and that these alterations are associated with increased oxidative stress and alterations in cellular signaling. |
