Assessment and characterization of DNA adducts produced by alkenylbenzenes in fetal turkey and chicken livers. (July 2019) - Kobets, Tetyana
Abstract: Formation of DNA adducts by five alkenylbenzenes, safrole, methyl eugenol, eugenol, and asarone with either α- or β-conformation, was analyzed in fetal avian livers in two in ovo models. DNA reactivity of the carcinogens safrole and methyl eugenol was previously demonstrated in the turkey egg model, whereas non-genotoxic eugenol was negative. In the current study, alkenylbenzenes were also tested in the chicken egg model. Injections with alkenylbenzenes were administered to fertilized turkey or chicken eggs for three consecutive days. Three hours after the last injection, liver samples were evaluated for DNA adduct formation using the 32 P-nucleotide postlabeling assay. DNA samples from turkey livers were also analyzed for adducts using mass spectrometry. In both species, genotoxic alkenylbenzenes safrole, methyl eugenol, α- and β-asarone produced DNA adducts, the presence and nature of which, with exception of safrole, were confirmed by mass spectrometry, validating the sensitivity of the 32 P-postlabeling assay. Overall, the results of testing were congruent between fetal turkey and chicken livers, confirming that these organisms can be used interchangeably. Moreover, data obtained in both models is comparable to genotoxicity findings in other species, supporting the usefulness of avian models for the assessment of genotoxicity as a potential alternative to animal models. Graphical abstract: Image 1 Highlights: Potential of five alkenylbenzenes to form DNA adducts was analyzed and compared in two in ovo models. 32 P-postlabeling detected adducts in fetal turkey and chicken livers produced by safrole, methyl eugenol, α- and β-asarone. DNA adducts produced by methyl eugenol, α- and β-asarone were confirmed in fetal turkey livers with mass spectrometry. Results of testing were congruent between the two in ovo models and comparable to genotoxicity findings in other species. In ovo models can be used for the assessment of chemical genotoxicity as potential alternative to animal models.