title: Mechanism of DNA damage and apoptosis induced by tetrahydropapaveroline, a metabolite of dopamine.
abstract: Tetrahydropapaveroline (THP), a metabolite of dopamine, has been suspected to be associated with dopaminergic neurotoxicity of L-DOPA. THP induced apoptosis in human leukemia cell line HL-60 cells, but did not in its hydrogen peroxide (H(2)O(2))-resistant clone HP100. THP-induced DNA ladder formation in HL-60 cells was inhibited by a metal chelator. THP induced damage to (32)P-labeled DNA fragments in the presence of metals. In the presence of Fe(III)EDTA, THP caused DNA damage at every nucleotide. The DNA damage was inhibited by free hydroxy radical ((.)OH) scavengers and catalase, suggesting that the Fe(III)EDTA-mediated DNA damage is mainly due to (.)OH generation. In the presence of Cu(II), THP caused DNA damage mainly at T and G of 5'-TG-3' sequence. The inhibitive effect of catalase and bathocuproine on Cu(II)-mediated DNA damage suggested that H(2)O(2) and Cu(I) participate in the DNA damage. This study demonstrated that THP-induced apoptosis via reactive oxygen species generated from reaction of H(2)O(2) and metals plays an important role in cytotoxicity of L-DOPA.
authors.affiliation: Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Japan.
authors.forename: Hatasu
authors.initials: H
authors.lastname: Kobayashi
authors.forename: Shinji
authors.initials: S
authors.lastname: Oikawa
authors.forename: Shosuke
authors.initials: S
authors.lastname: Kawanishi
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000378:metabolism; D002417:Cattle; D003300:Copper / Q000378:metabolism; D004249:DNA Damage; D053938:DNA Fragmentation; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004492:Edetic Acid / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D007477:Ions; D007502:Iron Chelating Agents / Q000378:metabolism; D008670:Metals / Q000737:chemistry; D015394:Molecular Structure; D010618:Phenanthrolines / Q000378:metabolism; D010880:Piperidines / Q000378:metabolism; D013765:Tetrahydropapaveroline / Q000633:toxicity*
chemical_list: D002121:Calcium Channel Blockers; D005290:Ferric Compounds; D016166:Free Radical Scavengers; D007477:Ions; D007502:Iron Chelating Agents; D008670:Metals; D010618:Phenanthrolines; D010880:Piperidines; D013765:Tetrahydropapaveroline; C032727:piperidine; D003300:Copper; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004492:Edetic Acid; C002478:bathocuproine; D003849:Deoxyguanosine; C019179:Fe(III)-EDTA; D004298:Dopamine