| spelling |
2022-08-17T19:56:10Z2022-08-17T19:56:10Z201833https://doi.org/10.1373/jalm.2017.0252542475-7241http://hdl.handle.net/1843/44331Background The serum troponin assay is the biochemical gold standard for detecting myocardial infarction (MI). A major diagnostic issue is that some believe troponin levels can rise with reversible injury, in the absence of radiologically detectable infarct. Hypothesis Because cell death activates intracellular proteases, troponin released by irreversible infarct will be more proteolyzed than that released by milder processes. Our goal was to quantify proteolytic digestion of cardiac troponin I in patients with varying degrees of myocardial injury. Methods Serum or plasma samples from 29 patients with cardiac troponin I elevations were analyzed for proteolytic degradation, using 3 different sandwich ELISAs designed to specifically detect the N-terminal, core, or C-terminal regions of cardiac troponin I. Results As predicted, the degree of proteolytic digestion increased with increasing severity of injury, as estimated by the total troponin level, and this trend was more pronounced for C-terminal (vs N-terminal) degradation. The highest degree of proteolytic digestion was observed in patients with ST-elevation MI; the least, in type 2 MI (supply–demand ischemia rather than acute thrombus formation). Conclusions The proteolytic degradation pattern of cardiac troponin I may be a better indicator of clinically significant MI than total serum troponin level. Distinguishing between intact and degraded forms of troponin may be useful for (a) identifying those patients with clinically significant infarct in need of revascularization, (b) monitoring intracellular proteolysis as a possible target for therapeutic intervention, and (c) providing an impetus for standardizing the epitopes used in the troponin I assay.Fundo O teste de troponina sérica é o padrão ouro bioquímico para detecção de infarto do miocárdio (IM). Uma grande questão diagnóstica é que alguns acreditam que os níveis de troponina podem aumentar com lesão reversível, na ausência de infarto radiologicamente detectável. Hipótese Como a morte celular ativa proteases intracelulares, a troponina liberada pelo infarto irreversível será mais proteolisada do que a liberada por processos mais brandos. Nosso objetivo foi quantificar a digestão proteolítica da troponina I cardíaca em pacientes com graus variados de lesão miocárdica. Métodos Amostras de soro ou plasma de 29 pacientes com elevações da troponina I cardíaca foram analisadas quanto à degradação proteolítica, usando 3 ELISAs sanduíche diferentes projetados para detectar especificamente as regiões N-terminal, central ou C-terminal da troponina I cardíaca. Resultados Como previsto, o grau de digestão proteolítica aumentou com o aumento da gravidade da lesão, conforme estimado pelo nível total de troponina, e esta tendência foi mais pronunciada para a degradação C-terminal (vs N-terminal). O maior grau de digestão proteolítica foi observado em pacientes com IAM com supradesnivelamento do segmento ST; o mínimo, no IAM tipo 2 (isquemia oferta-demanda em vez de formação aguda de trombo). Conclusões O padrão de degradação proteolítica da troponina I cardíaca pode ser um melhor indicador de IM clinicamente significativo do que o nível total de troponina sérica. A distinção entre as formas intactas e degradadas de troponina pode ser útil para (a) identificar os pacientes com infarto clinicamente significativo que necessitam de revascularização, (b) monitorar a proteólise intracelular como um possível alvo para intervenção terapêutica e (c) fornecer um impulso para a padronização os epítopos usados no ensaio de troponina I.engUniversidade Federal de Minas GeraisUFMGBrasilICB - INSTITUTO DE CIÊNCIAS BIOLOGICASThe journal of applied laboratory medicineFisiologiaTroponinaProteolytic Digestion of Serum Cardiac Troponin I as Marker of Ischemic SeverityDigestão proteolítica da troponina cardíaca sérica I como marcador de gravidade isquêmicainfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttps://academic.oup.com/jalm/article/3/3/450/5603172?login=falseSomaya ZahranVivian Paulino FigueiredoMichelle GrahamRichard SchulzPeter Hwangapplication/pdfinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFMGinstname:Universidade Federal de Minas Gerais (UFMG)instacron:UFMGLICENSELicense.txtLicense.txttext/plain; charset=utf-82042https://repositorio.ufmg.br/bitstream/1843/44331/1/License.txtfa505098d172de0bc8864fc1287ffe22MD51ORIGINAL2018_Proteolytic digestion of serum cardiac troponin i as marker of ischemic severity.pdf2018_Proteolytic digestion of serum cardiac troponin i as marker of ischemic severity.pdfapplication/pdf390256https://repositorio.ufmg.br/bitstream/1843/44331/2/2018_Proteolytic%20digestion%20of%20serum%20cardiac%20troponin%20i%20as%20marker%20of%20ischemic%20severity.pdf0d1c980cbbbd3d08937cb106f8a96568MD521843/443312022-08-17 16:56:10.379oai:repositorio.ufmg.br:1843/44331TElDRU7vv71BIERFIERJU1RSSUJVSe+/ve+/vU8gTu+/vU8tRVhDTFVTSVZBIERPIFJFUE9TSVTvv71SSU8gSU5TVElUVUNJT05BTCBEQSBVRk1HCiAKCkNvbSBhIGFwcmVzZW50Ye+/ve+/vW8gZGVzdGEgbGljZW7vv71hLCB2b2Pvv70gKG8gYXV0b3IgKGVzKSBvdSBvIHRpdHVsYXIgZG9zIGRpcmVpdG9zIGRlIGF1dG9yKSBjb25jZWRlIGFvIFJlcG9zaXTvv71yaW8gSW5zdGl0dWNpb25hbCBkYSBVRk1HIChSSS1VRk1HKSBvIGRpcmVpdG8gbu+/vW8gZXhjbHVzaXZvIGUgaXJyZXZvZ++/vXZlbCBkZSByZXByb2R1emlyIGUvb3UgZGlzdHJpYnVpciBhIHN1YSBwdWJsaWNh77+977+9byAoaW5jbHVpbmRvIG8gcmVzdW1vKSBwb3IgdG9kbyBvIG11bmRvIG5vIGZvcm1hdG8gaW1wcmVzc28gZSBlbGV0cu+/vW5pY28gZSBlbSBxdWFscXVlciBtZWlvLCBpbmNsdWluZG8gb3MgZm9ybWF0b3Mg77+9dWRpbyBvdSB277+9ZGVvLgoKVm9j77+9IGRlY2xhcmEgcXVlIGNvbmhlY2UgYSBwb2zvv710aWNhIGRlIGNvcHlyaWdodCBkYSBlZGl0b3JhIGRvIHNldSBkb2N1bWVudG8gZSBxdWUgY29uaGVjZSBlIGFjZWl0YSBhcyBEaXJldHJpemVzIGRvIFJJLVVGTUcuCgpWb2Pvv70gY29uY29yZGEgcXVlIG8gUmVwb3NpdO+/vXJpbyBJbnN0aXR1Y2lvbmFsIGRhIFVGTUcgcG9kZSwgc2VtIGFsdGVyYXIgbyBjb250Ze+/vWRvLCB0cmFuc3BvciBhIHN1YSBwdWJsaWNh77+977+9byBwYXJhIHF1YWxxdWVyIG1laW8gb3UgZm9ybWF0byBwYXJhIGZpbnMgZGUgcHJlc2VydmHvv73vv71vLgoKVm9j77+9IHRhbWLvv71tIGNvbmNvcmRhIHF1ZSBvIFJlcG9zaXTvv71yaW8gSW5zdGl0dWNpb25hbCBkYSBVRk1HIHBvZGUgbWFudGVyIG1haXMgZGUgdW1hIGPvv71waWEgZGUgc3VhIHB1YmxpY2Hvv73vv71vIHBhcmEgZmlucyBkZSBzZWd1cmFu77+9YSwgYmFjay11cCBlIHByZXNlcnZh77+977+9by4KClZvY++/vSBkZWNsYXJhIHF1ZSBhIHN1YSBwdWJsaWNh77+977+9byDvv70gb3JpZ2luYWwgZSBxdWUgdm9j77+9IHRlbSBvIHBvZGVyIGRlIGNvbmNlZGVyIG9zIGRpcmVpdG9zIGNvbnRpZG9zIG5lc3RhIGxpY2Vu77+9YS4gVm9j77+9IHRhbWLvv71tIGRlY2xhcmEgcXVlIG8gZGVw77+9c2l0byBkZSBzdWEgcHVibGljYe+/ve+/vW8gbu+/vW8sIHF1ZSBzZWphIGRlIHNldSBjb25oZWNpbWVudG8sIGluZnJpbmdlIGRpcmVpdG9zIGF1dG9yYWlzIGRlIG5pbmd177+9bS4KCkNhc28gYSBzdWEgcHVibGljYe+/ve+/vW8gY29udGVuaGEgbWF0ZXJpYWwgcXVlIHZvY++/vSBu77+9byBwb3NzdWkgYSB0aXR1bGFyaWRhZGUgZG9zIGRpcmVpdG9zIGF1dG9yYWlzLCB2b2Pvv70gZGVjbGFyYSBxdWUgb2J0ZXZlIGEgcGVybWlzc++/vW8gaXJyZXN0cml0YSBkbyBkZXRlbnRvciBkb3MgZGlyZWl0b3MgYXV0b3JhaXMgcGFyYSBjb25jZWRlciBhbyBSZXBvc2l077+9cmlvIEluc3RpdHVjaW9uYWwgZGEgVUZNRyBvcyBkaXJlaXRvcyBhcHJlc2VudGFkb3MgbmVzdGEgbGljZW7vv71hLCBlIHF1ZSBlc3NlIG1hdGVyaWFsIGRlIHByb3ByaWVkYWRlIGRlIHRlcmNlaXJvcyBlc3Tvv70gY2xhcmFtZW50ZSBpZGVudGlmaWNhZG8gZSByZWNvbmhlY2lkbyBubyB0ZXh0byBvdSBubyBjb250Ze+/vWRvIGRhIHB1YmxpY2Hvv73vv71vIG9yYSBkZXBvc2l0YWRhLgoKQ0FTTyBBIFBVQkxJQ0Hvv73vv71PIE9SQSBERVBPU0lUQURBIFRFTkhBIFNJRE8gUkVTVUxUQURPIERFIFVNIFBBVFJPQ++/vU5JTyBPVSBBUE9JTyBERSBVTUEgQUfvv71OQ0lBIERFIEZPTUVOVE8gT1UgT1VUUk8gT1JHQU5JU01PLCBWT0Pvv70gREVDTEFSQSBRVUUgUkVTUEVJVE9VIFRPRE9TIEUgUVVBSVNRVUVSIERJUkVJVE9TIERFIFJFVklT77+9TyBDT01PIFRBTULvv71NIEFTIERFTUFJUyBPQlJJR0Hvv73vv71FUyBFWElHSURBUyBQT1IgQ09OVFJBVE8gT1UgQUNPUkRPLgoKTyBSZXBvc2l077+9cmlvIEluc3RpdHVjaW9uYWwgZGEgVUZNRyBzZSBjb21wcm9tZXRlIGEgaWRlbnRpZmljYXIgY2xhcmFtZW50ZSBvIHNldSBub21lKHMpIG91IG8ocykgbm9tZXMocykgZG8ocykgZGV0ZW50b3IoZXMpIGRvcyBkaXJlaXRvcyBhdXRvcmFpcyBkYSBwdWJsaWNh77+977+9bywgZSBu77+9byBmYXLvv70gcXVhbHF1ZXIgYWx0ZXJh77+977+9bywgYWzvv71tIGRhcXVlbGFzIGNvbmNlZGlkYXMgcG9yIGVzdGEgbGljZW7vv71hLgo=Repositório InstitucionalPUBhttps://repositorio.ufmg.br/oaiopendoar:2022-08-17T19:56:10Repositório Institucional da UFMG - Universidade Federal de Minas Gerais (UFMG)false
|