title: Phenols of virgin olive oil protects nuclear DNA against oxidative damage in HeLa cells.
abstract: Oxidative DNA damage is an inescapable consequence for cells constantly exposed to oxidative stress derived from normal metabolic processes and from environmental factors. Phenolic compounds, which have strong antioxidant activity, prevent DNA damage by protecting the cells against harmful effects of oxidative stress. In this study, the effect of virgin olive oil phenolic extract (OOPE) was investigated on H2O2-induced mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) damage in HeLa cells. DNA damage was assessed in mitochondria and two nuclear regions by using quantitative PCR (QPCR) assay. The cells were pre-treated with non-cytotoxic doses of OOPE for 4 h, and DNA damage was determined. OOPE alone does not change the steady-state level of DNA damage. The oxidative stress generated with 750 μM H2O2 caused two times greater damages in mtDNA compared to nDNA, which included the nonexpressed β-globin region (1.507±0.110 lesions/10 kb) and the expressed APEX1 gene (1.623±0.243 lesions/10 kb) with respect to the control region. When cells were preincubated with OOPE for 4 h, nDNA damage under stress condition was completely inhibited; however, mtDNA damage was not affected by this procedure. These results suggest that OOPE has a protective effect against nDNA damage in HeLa cells.
authors.affiliation: Department of Biology, Faculty of Arts and Sciences, University of Çanakkale Onsekiz Mart, Terzioglu Campus, 17020 Çanakkale, Turkey. ozlemerol@comu.edu.tr
authors.forename: Özlem
authors.initials: Ö
authors.lastname: Erol
authors.forename: Nazlı
authors.initials: N
authors.lastname: Arda
authors.forename: Günhan
authors.initials: G
authors.lastname: Erdem
mesh_terms: D004249:DNA Damage / Q000187:drug effects*; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007700:Kinetics; D000069463:Olive Oil; D010084:Oxidation-Reduction; D019800:Phenol / Q000737:chemistry / Q000494:pharmacology*; D010938:Plant Oils / Q000737:chemistry*
chemical_list: D000069463:Olive Oil; D010938:Plant Oils; D019800:Phenol; D006861:Hydrogen Peroxide