Fibrinogen nitrotyrosination after ischemic stroke impairs thrombolysis and promotes neuronal death

BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR BASIS OF DISEASE

卷:1852

Article

Ill-Raga, Gerard¹  Palomer, Ernest¹  Ramos-Fernandez, Eva¹  Guix, Francesc X.¹  Bosch-Morato, Monica¹  Guivernau, Biuse¹  Tajes, Marta¹  Valls-Comamala, Victoria¹  Jimenez-Conde, Jordi²  Ois, Angel²  Perez-Asensio, Fernando³  Reyes-Navarro, Mario⁴  Caballo, Carolina⁵  Gil-Gomez, Gabriel⁶  Lopez-Vilchez, Irene⁵  Galan, Ana M.⁵  Alameda, Francesc⁷  Escolar, Gines⁵  Opazo, Carlos^4,8  Planas, Anna M.³  Roquer, Jaume²  Valverde, Miguel A.¹  Munoz, Francisco J.¹ 

[1] Univ Pompeu Fabra, Lab Mol Physiol & Channelopathies, Barcelona 08003, Spain

[2] Hosp Mar IMIM Parc Salut Mar, Serv Neurol, Barcelona 08003, Spain

[3] CSIC, IDIBAPS, IIBB, Barcelona 08036, Spain

[4] Univ Concepcion, Dept Physiol, Lab Neurobiometals, Concepcion 4089100, Chile

[5] Univ Barcelona, Inst Biomed Res August Pi & Sunyer, Biomed Diag Ctr, Dept Hemotherapy & Hemostasis,Hosp Clin, Barcelona 08036, Spain

[6] Inst Hosp Mar Invest Med IMIM, Barcelona 08003, Spain

[7] Hosp Mar IMIM Parc Salut Mar, Serv Anat Patol, Barcelona 08003, Spain

[8] Univ Melbourne, Florey Inst Neurosci & Mental Hlth, Oxidat Biol Lab, Melbourne 3010, Australia

关键词: Ischemic stroke;    Fibrinogen;    Nitric oxide;    Peroxynitrite;    Apoptosis;   

DOI  :  10.1016/j.bbadis.2014.12.007

来源: Elsevier

【 摘 要 】

Ischemic stroke is an acute vascular event that compromises neuronal viability, and identification of the pathophysiological mechanisms is critical for its correct management. Ischemia produces increased nitric oxide synthesis to recover blood flow but also induces a free radical burst. Nitric oxide and superoxide anion react to generate peroxynitrite that nitrates tyrosines. We found that fibrinogen nitrotyrosination was detected in plasma after the initiation of ischemic stroke in human patients. Electron microscopy and protein intrinsic fluorescence showed that in vitro nitrotyrosination of fibrinogen affected its structure. Thromboelastography showed that initially fibrinogen nitrotyrosination retarded clot formation but later made the clot more resistant to fibrinolysis. This result was independent of any effect on thrombin production. Immunofluorescence analysis of affected human brain areas also showed that both fibrinogen and nitrotyrosinated fibrinogen spread into the brain parenchyma after ischemic stroke. Therefore, we assayed the toxicity of fibrinogen and nitrotyrosinated fibrinogen in a human neuroblastoma cell line. For that purpose we measured the activity of caspase-3, a key enzyme in the apoptotic pathway, and cell survival. We found that nitrotyrosinated fibrinogen induced higher activation of caspase 3. Accordingly, cell survival assays showed a more neurotoxic effect of nitrotyrosinated fibrinogen at all concentrations tested. In summary, nitrotyrosinated fibrinogen would be of pathophysiological interest in ischemic stroke due to both its impact on hemostasis it impairs thrombolysis, the main target in stroke treatments and its neurotoxicity that would contribute to the death of the brain tissue surrounding the infarcted area. (C) 2014 Published by Elsevier B.V.

【 授权许可】

Free