title: A novel thiol oxidation-based mechanism for adriamycin-induced cell injury in human macrophages.
abstract: Adriamycin is a widely used antitumor antibiotic, but its use has been limited by its cytotoxicity in both cardiomyocytes and non-cardiac tissues. While adriamycin's ability to redox cycle via one-electron transfer reactions and generate ROS is thought to promote cardiotoxicity, the mechanisms involved in non-cardiac tissue injury are not clear. Here we show that prolonged exposure (48 h) of human monocyte-derived macrophages to adriamycin at concentrations as low as 1 microM promotes caspase-independent cell death. Treatment of cells with scavengers of superoxide and peroxyl radicals blocked adriamycin-induced oxidation of dichlorodihydrofluorescein (DCFH) but did not prevent macrophage injury. Macrophages treated with either adriamycin or the thiol oxidant diamide showed elevated levels of glutathione disulfide and increased protein-S-glutathionylation prior to cell injury, indicating that thiol oxidation is involved in adriamycin-induced macrophage death. Furthermore, inhibition of glutathione reductase (GR) with 1,3-bis[2-chloroethyl]-1-nitrosourea or transfection of macrophages with small inhibitory RNA (siRNA) directed against GR or glutaredoxin (Grx) potentiated adriamycin-induced macrophage injury. Thus, both GR and Grx appear to play a crucial role in protecting macrophages from adriamycin-induced cell injury. These findings suggest a new mechanism for adriamycin-induced tissue injury whereby thiol oxidation, rather than one-electron redox cycling and ROS generation, mediates adriamycin-induced cell damage.
authors.affiliation: Division of Cardiovascular Medicine and Graduate Center for Nutritional Sciences, University of Kentucky, USA. asmis@uthscsa.edu
authors.forename: Reto
authors.initials: R
authors.lastname: Asmis
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.forename: Marta
authors.initials: M
authors.lastname: Kisgati
authors.forename: Jim G
authors.initials: JG
authors.lastname: Begley
authors.forename: John J
authors.initials: JJ
authors.lastname: Mieyal
mesh_terms: D018906:Antineoplastic Agents, Alkylating / Q000494:pharmacology; D002330:Carmustine / Q000494:pharmacology; D003958:Diamide / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology*; D004583:Electrons; D005452:Fluoresceins / Q000494:pharmacology; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism; D019803:Glutathione Disulfide / Q000737:chemistry; D005980:Glutathione Reductase / Q000378:metabolism; D006801:Humans; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008954:Models, Biological; D009000:Monocytes / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000473:pathology; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010100:Oxygen / Q000737:chemistry*; D034741:RNA, Small Interfering / Q000378:metabolism; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013997:Time Factors; D014162:Transfection; D014945:Wound Healing
chemical_list: D018906:Antineoplastic Agents, Alkylating; D005452:Fluoresceins; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D003958:Diamide; C065013:2',7'-dichlorodihydrofluorescein; D004317:Doxorubicin; D005980:Glutathione Reductase; D005978:Glutathione; D010100:Oxygen; D002330:Carmustine; D019803:Glutathione Disulfide