title: Immunohistochemical detection of a substituted 1,N(2)-ethenodeoxyguanosine adduct by omega-6 polyunsaturated fatty acid hydroperoxides in the liver of rats fed a choline-deficient, L-amino acid-defined diet.
abstract: Endogenous lipid peroxidation products react with DNA and form exocyclic DNA adducts. The purpose of this study was to investigate the in vivo formation of 7-(2-oxo-heptyl)-substituted 1,N(2)-etheno-2'-deoxyguanosine adduct (Oxo-heptyl-varepsilondG), one of the major products from the reaction of 13-hydroperoxyoctadecadienoic acid (13-HPODE) with dG. The monoclonal antibody specific to Oxo-heptyl-varepsilondG was prepared using a chemically synthesized conjugate of Oxo-heptyl-varepsilondG and carrier protein as immunogen. The characterization showed that the obtained antibody (mAb6A3) is specific to the Oxo-heptyl-varepsilondG moiety. Using the novel antibody, the presence of the Oxo-heptyl-varepsilondG adduct in vivo was immunohistochemically revealed in the liver of rats fed a choline-deficient, L-amino acid-defined diet, an endogenous carcinogenesis model, for 3 days. In addition, the Oxo-heptyl-varepsilondG formation was confirmed in DNAs treated with peroxidized linoleic acid, arachidonic acid and gamma-linolenic acid, respectively, suggesting that the hydroperoxides of omega-6 polyunsaturated fatty acids could be the potential sources of Oxo-heptyl-varepsilondG formation in vivo. Collectively, the results in this study suggest the first evidence that the formation of Oxo-heptyl-varepsilondG, the omega-6 lipid hydroperoxide-mediated DNA adduct, may be a potential biomarker for the early phase of carcinogenesis.
authors.affiliation: Laboratory of Food and Biodynamics, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan.
authors.forename: Yoshichika
authors.initials: Y
authors.lastname: Kawai
authors.forename: Yoji
authors.initials: Y
authors.lastname: Kato
authors.forename: Dai
authors.initials: D
authors.lastname: Nakae
authors.forename: Osamu
authors.initials: O
authors.lastname: Kusuoka
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Konishi
authors.forename: Koji
authors.initials: K
authors.lastname: Uchida
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Osawa
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D015415:Biomarkers / Q000032:analysis; D002794:Choline / Q000378:metabolism*; D018736:DNA Adducts / Q000032:analysis / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D005526:Food, Formulated; D007150:Immunohistochemistry; D015227:Lipid Peroxidation; D008054:Lipid Peroxides / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D051381:Rats
chemical_list: D000596:Amino Acids; D000911:Antibodies, Monoclonal; D015415:Biomarkers; D018736:DNA Adducts; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D008054:Lipid Peroxides; D003849:Deoxyguanosine; D002794:Choline