Genotoxic effect induced by hydrogen peroxide in human hepatoma cells using comet assay

Original article


Ghazalla M. Benhusein 1, Elaine Mutch 2, Suher Aburawi 1, Faith M. Williams 2

1-Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Al-Fateh University for Medical Sciences, Tripoli, Libya; 2-The Toxicology Unit, Institute for Research on Environment & Sustainability and Medical Toxicology Centre, Newcastle University, Newcastle Upon Tyne, UK

Libyan J Med 2010, 5: 4637 – DOI: 10.3402/ljm.v5i0.4


Background: Hydrogen peroxide is a common reactive oxygen intermediate generated by various forms of oxidative stress. Aims: The aim of this study was to investigate the DNA damage capacity of H2O2 in HepG2 cells. Methods: Cells were treated with H2O2 at concentrations of 25 µM or 50 µM for 5 min, 30 min, 40 min, 1 h or 24 h in parallel. The extent of DNA damage was assessed by the comet assay. Results: Compared to the control, DNA damage by 25 µM and 50 µM H2O2 increased significantly with increasing incubation time up to 1 h, but it was not increased at 24 h. Conclusions: Our Findings confirm that H2O2 is a typical DNA damage inducing agent and thus is a good model system to study the effects of oxidative stress. DNA damage in HepG2 cells increased significantly with H2O2 concentration and time of incubation but later decreased likely due to DNA repair mechanisms and antioxidant enzymes.

Keywords: DNA damage, Hydrogen peroxide, HepG2 cells, Comet assay.