Abstract
Background: Hydrogen peroxide is a natural source of oxidative DNA damage in cells generate reactive oxygen species (ROS), which are responsible for DNA damage and apoptosis. Aim: We investigated the susceptibility of HepG2 and HaCat cells to DNA damage capacity induced by hydrogen peroxide, as well as to compare the differential sensitivities of both types of cells to DNA damage. Methods: HepG2 and HaCat cells were challenged with 25 µM hydrogen peroxide for 5, 30, 40, 60 min and 24 hr using Comet assay. Results: DNA damage was significantly increased in both HepG2 and HaCat cells at all times of incubation (p<0.001), but not at 24hr. Furthermore, there was a clear decrease in the amount of DNA damage was observed at 24 hr time of incubation, which is accompanied with decrease in DNA migration length in both HepG2 and HaCat cells. Conclusion: Our results confirm that the profile of DNA damage induced by hydrogen peroxide was similar in both HepG2 and HaCat cells. However, the reduction in the amount of DNA damage could be due to of possibility of cellular DNA repair.