Data from Effects of Black Raspberry Extract and Protocatechuic Acid on Carcinogen-DNA Adducts and Mutagenesis, and Oxidative Stress in Rat and Human Oral Cells

Abstract

<div>Abstract<p>Effects of black raspberry (BRB) extract and protocatechuic acid (PCA) on DNA adduct formation and mutagenesis induced by metabolites of dibenzo[a,l]pyrene (DBP) were investigated in rat oral fibroblasts. The DBP metabolites, (±)-anti-11,12-dihydroxy-11,12,-dihydrodibenzo[a,l]pyrene (DBP-diol) and 11,12-dihydroxy-13,14-epoxy-11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DBPDE) induced dose-dependent DNA adducts and mutations. DBPDE was considerably more potent, whereas the parent compound had no significant effect. Treatment with BRB extract (BRBE) and PCA resulted in reduced DBP-derived DNA adduct levels and reduced mutagenesis induced by DBP-diol, but only BRBE was similarly effective against (DBPDE). BRBE did not directly inactivate DBPDE, but rather induced a cellular response—enhanced DNA repair. When BRBE was added to cells 1 day after the DBP-diol, the BRBE greatly enhanced removal of DBP-derived DNA adducts. As oxidative stress can contribute to several stages of carcinogenesi<i>s</i>, BRBE and PCA were investigated for their abilities to reduce oxidative stress in a human leukoplakia cell line by monitoring the redox indicator, 2′,7′-dichlorodihydrofluorescein diacetate (H<sub>2</sub>DCF) in cellular and acellular systems. BRBE effectively inhibited the oxidation, but PCA was only minimally effective against H<sub>2</sub>DCF. These results taken together provide evidence that BRBE and PCA can inhibit initiation of carcinogenesis by polycyclic aromatic hydrocarbons; and in addition, BRBE reduces oxidative stress. <i>Cancer Prev Res; 9(8); 704–12. ©2016 AACR</i>.</p></div>