Quercetin Mediated Inhibition of Hydrogen Peroxide-induced Genomic DNA Damage and Toxicity

Abstract

Flavonoids are reported to exhibit a wide variety of biological effects including antioxidant activities. The present study aims to explore the protective effect of the flavonol quercetin against hydrogen peroxide-mediated damage. The effects of quercetin on H₂O₂-mediated DNA damage were evaluated using spectrophotometric analyses, DNA damage monitoring by gel electrophoresis, cell viability, CBMN assay, comet assay and chromosomal aberration study inhuman peripheral blood lymphocytes. Quercetin was found to be protective at 30 μM in the cell viability study, while it showed its maximum efficacy in the CBMN assay and comet assay at a concentration level of 40 μM against H₂O₂-induced damage. Spectrophotometric analyses speculated that the intercalation is the possible binding mode of quercetin with DNA and prevented oxidative stress-induced DNA damage. This study successfully establishes quercetin as a protective agent against oxidative DNA damage induced by H₂O₂.

Key words:

• Hydrogen peroxide
• free radicals
• DNA damage
• calf thymus DNA
• CBMN assay