title: Formation of 8-nitroguanosine in cellular RNA as a biomarker of exposure to reactive nitrogen species.
abstract: Reactive nitrogen species, such as peroxynitrite, nitrogen oxides and nitryl chloride, have been implicated as a cause of diverse pathophysiological conditions, including inflammation, neurodegenerative and cardiovascular diseases and cancer. We previously reported that 8-nitroguanine is formed by reactions of guanine or calf-thymus DNA with peroxynitrite in vitro. In the present study, we have studied the formation of 8-nitroguanosine and 8-oxo-7,8-dihydroguanosine in reactions of calf-liver RNA with various reactive nitrogen species. 8-Nitroguanosine in RNA was found to be much more stable than 8-nitro-2' -deoxyguanosine in DNA, which rapidly depurinates to release 8-nitroguanine. Both 8-nitroguanosine and 8-oxo-7,8-dihydroguanosine were formed in calf-liver RNA following exposure to various reactive nitrogen species, such as synthetic peroxynitrite. They were also formed in RNA by reactive species formed from nitric oxide and superoxide anion generated concomitantly from 3-morpholino-sydnonimine (SIN-1) and those formed with myeloperoxidase or horseradish peroxidase in the presence of nitrite and hydrogen peroxide. 8-Nitroguanosine was detected by HPLC with an electrochemical detector in enzymatic hydrolyzates of RNA isolated from human lung carcinoma cells incubated with synthetic peroxynitrite. Our results indicate that 8-nitroguanosine in cellular RNA could be measured as a marker of damage caused by endogenous reactive nitrogen species in tissues and cells.
authors.affiliation: Unit of Endogenous Cancer Risk Factors, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon, Cedex 08, France.
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Masuda
authors.forename: Hoyoku
authors.initials: H
authors.lastname: Nishino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohshima
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D015415:Biomarkers / Q000032:analysis; D002277:Carcinoma / Q000378:metabolism; D002417:Cattle; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D006147:Guanine / Q000031:analogs & derivatives* / Q000378:metabolism*; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism; D008981:Molsidomine / Q000031:analogs & derivatives* / Q000378:metabolism; D030421:Peroxynitrous Acid / Q000378:metabolism / Q000494:pharmacology*; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism*; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
chemical_list: C095838:8-nitroguanine; D015415:Biomarkers; D012334:RNA, Neoplasm; D030421:Peroxynitrous Acid; C002385:linsidomine; D006147:Guanine; D000080242:8-Hydroxy-2'-Deoxyguanosine; D008981:Molsidomine; D003849:Deoxyguanosine