title: Mechanism of oxidative DNA damage induced by capsaicin, a principal ingredient of hot chili pepper.
abstract: Although capsaicin exhibits antitumor activity, carcinogenic potential has also been reported. To clarify the mechanism for expression of potential carcinogenicity of capsaicin, we examined DNA damage induced by capsaicin in the presence of metal ion and various kinds of cytochrome P450 (CYP) using 32P-5'-end-labeled DNA fragments. Capsaicin induced Cu(II)-mediated DNA damage efficiently in the presence of CYP1A2 and partially in the presence of 2D6. CYP1A2-treated capsaicin caused double-base lesions at 5'-TG-3', 5'-GC-3' and CG of the 5'-ACG-3' sequence complementary to codon 273, a hotspot of p53 gene. DNA damage was inhibited by catalase and bathocuproine, a Cu(I) chelator, suggesting that reactive species derived from the reaction of H2O2 with Cu(I) participate in DNA damage. Formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine was significantly increased by CYP1A2-treated capsaicin in the presence of Cu(II). Therefore, we conclude that Cu(II)-mediated oxidative DNA damage by CYP-treated capsaicin seems to be relevant for the expression of its carcinogenicity.
authors.affiliation: Mie University Graduate School of Medicine, Department of Environmental and Molecular Medicine, Mie, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Oikawa
authors.forename: Emiko
authors.initials: E
authors.lastname: Nagao
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Sakano
authors.forename: Shosuke
authors.initials: S
authors.lastname: Kawanishi
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D002211:Capsaicin / Q000737:chemistry*; D002212:Capsicum / Q000737:chemistry*; D002374:Catalase / Q000737:chemistry; D002417:Cattle; D003300:Copper / Q000737:chemistry; D019388:Cytochrome P-450 CYP1A2 / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004249:DNA Damage; D053938:DNA Fragmentation; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000138:chemical synthesis; D006801:Humans; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010618:Phenanthrolines / Q000737:chemistry; D028321:Plant Preparations / Q000737:chemistry
chemical_list: D010618:Phenanthrolines; D028321:Plant Preparations; D003300:Copper; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; C002478:bathocuproine; D002374:Catalase; C504573:CYP1A2 protein, human; D019388:Cytochrome P-450 CYP1A2; D003849:Deoxyguanosine; D002211:Capsaicin