title: Protecting against peroxynitrite-mediated cytotoxicity in vascular smooth muscle cells via upregulating endogenous glutathione biosynthesis by 3H-1,2-dithiole-3-thione.
abstract: Peroxynitrite (ONOO(-)) is critically involved in the pathogenesis of cardiovascular diseases. Reaction with glutathione (GSH) was proposed to be a major detoxification pathway of ONOO(-) in the biological system. This study was undertaken to determine if chemically elevated intracellular GSH affords protection against ONOO(-)-mediated toxicity in vascular cells. Incubation of aortic smooth muscle A10 cells with 3H-1,2-dithiole-3-thione (D3T) led to a concentration- and time-dependent elevation of cellular GSH. Treatment of the cells with D3T also augmented protein and gene expression of gamma-glutamylcysteine ligase. To examine the effects of D3T-induced GSH on ONOO(-)-mediated toxicity, we pretreated A10 cells with D3T and then exposed them to either authentic ONOO(-) or the ONOO(-) generator, 3-morpholinosydnonimine. We observed that D3T pretreatment of A10 cells resulted in a significant protection against ONOO(-) cytotoxicity. Conversely, depletion of cellular GSH by buthionine sulfoximine (BSO) caused a marked potentiation of ONOO(-) cytotoxicity. To further demonstrate the causal involvement of GSH induction in D3T cytoprotection, we cotreated A10 cells with BSO to abolish D3T-induced GSH elevation. BSO cotreatment was found to greatly reverse the protective effects of D3T on ONOO(-)-elicited cytotoxicity. Taken together, our results demonstrate that upregulating GSH biosynthesis by D3T results in a marked protection against ONOO(-)-induced toxicity in vascular cells.
authors.affiliation: Department of Pharmaceutical Sciences, St. John's University College of Pharmacy and Allied Health Professions, 8000 Utopia Parkway, Jamaica, NY 11439, USA.
authors.forename: Zhuoxiao
authors.initials: Z
authors.lastname: Cao
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Li
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004151:Dipeptides / Q000096:biosynthesis / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D004338:Drug Combinations; D005978:Glutathione / Q000096:biosynthesis*; D008981:Molsidomine / Q000031:analogs & derivatives* / Q000633:toxicity; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D030421:Peroxynitrous Acid / Q000633:toxicity*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013871:Thiones / Q000494:pharmacology*; D013876:Thiophenes / Q000494:pharmacology*; D015854:Up-Regulation
chemical_list: D000970:Antineoplastic Agents; D004151:Dipeptides; D004338:Drug Combinations; D012333:RNA, Messenger; D013871:Thiones; D013876:Thiophenes; D030421:Peroxynitrous Acid; D019328:Buthionine Sulfoximine; C002385:linsidomine; D008981:Molsidomine; D005978:Glutathione; C017341:gamma-glutamylcysteine; C049325:1,2-dithiol-3-thione