title: Free radical damage to deoxyribose by anthracycline, aureolic acid and aminoquinone antitumour antibiotics. An essential requirement for iron, semiquinones and hydrogen peroxide.
abstract: Anthracycline, aureolic acid and aminoquinone antitumour antibiotics damage deoxyribose in cell-free systems when reduced in air by the enzyme ferredoxin reductase. Damage to deoxyribose is inhibited by the iron chelator desferrioxamine, the copper-containing protein caeruloplasmin and catalase but not by superoxide dismutase. Scavengers of the hydroxyl radical such as formate, butan-1-ol, ethanol and benzoate do not offer much protection, whereas mannitol and thiourea do. These findings point to a site-specific Fenton reaction in which the drug semiquinones reduce complexed iron and dioxygen leading to the formation of hydrogen peroxide and a ferrous complex.
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000633:toxicity*; D016227:Benzoquinones; D002374:Catalase / Q000494:pharmacology; D003676:Deferoxamine / Q000494:pharmacology; D003855:Deoxyribose; D006861:Hydrogen Peroxide; D006878:Hydroxides; D017665:Hydroxyl Radical; D007501:Iron; D009279:Naphthacenes / Q000633:toxicity; D008926:Plicamycin / Q000633:toxicity*; D011809:Quinones; D013482:Superoxide Dismutase / Q000494:pharmacology
chemical_list: D000903:Antibiotics, Antineoplastic; D016227:Benzoquinones; D006878:Hydroxides; D009279:Naphthacenes; D011809:Quinones; C025232:semiquinone radicals; D017665:Hydroxyl Radical; D003855:Deoxyribose; D006861:Hydrogen Peroxide; D007501:Iron; D002374:Catalase; D013482:Superoxide Dismutase; D003676:Deferoxamine; D008926:Plicamycin