Neuro-protective effects of cerium and yttrium oxide nanoparticles on high glucose-induced oxidative stress and apoptosis in undifferentiated PC12 cells

Objective: Oxidative stress has been recognized as the major factor for the development of diabetes and its complications. Cerium oxide and Yttrium oxide nanoparticles are known as free radicals scavengers. The aim of this study was to investigate the protective effect of CeO2 and Y2O3 on oxidative stress induced by high glucose in undifferentiated rat pheochromocytoma (PC12) cells. Methods: In this study, undifferentiated PC12 cells were exposed to high glucose (25 mg/ml, 24 hours) and the protective effects of CeO2 and Y2O3 nanoparticles were evaluated. The viability of undifferentiated PC12 cells was determined by MTT assay. The levels of reactive oxygen species (ROS) were measured using 2,7-dichlorodihydrofluorescein diacetate (DCF). The expression levels of pro-apoptotic Bax, antiapoptotic Bcl-2 and caspase3 proteins were also detected by western blotting. Total antioxidant power (TAP), total thiol molecules (TTM) and lipid peroxidation (LPO) were also evaluated. Results: CeO2 and Y2O3 increased survival of undifferentiated PC12 cells exposed to high glucose-induced oxidative stress. CeO2 and Y2O3 pre-treatment decreased ROS production, LPO, Bax and caspase-3 proteins expression. Both nanoparticles have also increased the TTM and Bcl-2 protein expression. Discussion: These findings suggest that CeO2 and Y2O3 protect the undifferentiated PC12 cells against the oxidative stress and apoptosis induced by high glucose.