Nanoalumina induces apoptosis by impairing antioxidant enzyme systems in human hepatocarcinoma cells

Alumina nanoparticles (Al(2)O(3)NPs) are gradually used in various areas, including nanomedicine, biosensors, and electronics. The current study aimed to explore the DNA damage and cytotoxicity due to Al(2)O(3)NPs on human hepatocarcinoma cells (HepG2). The MTT and neutral red uptake assays showed that Al(2)O(3)NPs induce significant cell death in a dose- and time-dependent manner. However, Al(2)O(3)NPs induced significant intracellular reactive oxygen species production and elevated lipid peroxidation and superoxide dismutase levels in the HepG2 cells. Al(2)O(3)NPs also induced significant decrease in reduced glutathione levels and increase caspase-3 activity in HepG2 cells. DNA fragmentation analysis using the alkaline single-cell gel electrophoresis showed that Al(2)O(3)NPs cause genotoxicity in dose- and time-dependent manner. However, they induce reactive oxygen species production and oxidative stress, leading to oxidative DNA damage, a probable mechanism of genotoxicity. This study warrants more careful assessment of Al(2)O(3)NPs before their industrial application.