Abstract
Purpose::
It has been reported that intravitreal injection of Cerium oxide nanoparticles protect photoreceptor cells against light-induced degeneration (Chen, J. , Patil, S. , Seal, S. and McGinnis, J. F. Nature Nanotech. 2006). In this study, the protective effects of Cerium nanoparticles against hydrogen peroxide (H2O2)-induced cell death of human retinal pigment epithelium (RPE) cells were examined.
Methods::
A human RPE cell line (ARPE-19) was used. The RPE cells were grown in DMEM with 10% FBS and 10IU/ml of penicillin in sterilized six well plates. Cells were grown to confluence in an incubator with an atmosphere of 5% CO2, 95% air at 37°C. Different concentrations of Cerium oxide nanoparticles were added to the cultures before exposure to various concentrations of H2O2. Cells were collected after trypsin digestion and Cell death was determined by flow cytometry using an Annexin V-FITC kit (Beckman Coulter Inc, Fullerton, CA) according to the manufacturer’s instructions.
Results::
No cytotoxicity was detected at any concentration of Nanoceria particles tested up to 10 nM. There was a clear dose-dependent effect of nanoparticles against 200 µM concentration of H2O2. Treatment with a 10nM suspension of Nanoceria particles demonstrated the best protective effect. Interestingly, the 10 nM nanoparticle treatment also effectively inhibited 400 and 600 µM H2O2-induced RPE cell death.
Conclusions::
Our data demonstrate that Cerium Oxide nanoparticles, in a dose-dependent manner, significantly decrease the death of RPE cells induced by H2O2. This indicates that Cerium oxide nanoparticles may be useful in protecting RPE cells in vivo which might delay or prevent the development of age-related macular degeneration.
Keywords: retinal pigment epithelium • oxidation/oxidative or free radical damage • age-related macular degeneration