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Efeitos do tempol sobre a interação entre peroxinitrito/CO2 com albumina e macrófagos: inibição da nitração de tirosinas e da oxidação de cisteínas e amplificação da nitrosação de cisteínas / Effects of tempol on the interaction between peroxynitrite/CO2 with albumin and macrophages: Inhibition of the nitration of tyrosine and oxidation of cysteine and amplification of cysteine nitrosationFernandes, Denise de Castro 19 February 2004 (has links)
O tempol (TP) tem se mostrado um eficiente protetor em modelos inflamatórios. Os mecanismos de proteção contra espécies reativas de oxigênio foi bastante estudado mas sua interação com espécies reativas de nitrogênio ainda permanece pouco explorada. Recentemente, propusemos que o TP re-direciona a nitração de fenol mediada por peroxintrito (PN)/CO2 para nitrosação, pela sua reação com o radical CO3•‾. O produto desta reação, o cátion oxamônio, oxidaria PN para O2 e •NO. Este último produziria uma espécie nitrosante (N2O3) pela reação com o radical derivado do PN, •NO2 [Bonini e col. (2002) Chem. Res. Tox. 15: 506]. Para examinar se este mecanismo poderia operar in vivo, estudamos os efeitos do TP na reatividade do PN/CO2 frente a albumina (BSA) e macrófagos. Os efeitos do TP se apresentaram dependentes de sua concentração e da concentração de Cys. Apesar do TP não se mostrar catalítico, ele inibiu a oxidação de Cys (20-50%) e nitração de Tyr (70-90%) da BSA e aumentou a nitrosação de Cys (200-400%). No caso dos macrófagos tratados com PN/CO2, o tempol também inibiu a nitração (90%) e aumentou a nitrosação (300%). Assim, em condições fisiológicas, concentrações sub-estequiométricas de TP seriam capazes de redirecionar a reatividade dos radicais derivados PN, de oxidação de Cys proteica e nitração de Tyr para nitrosação de Cys. Desta forma, o TP poderia inibir a injúria em inflamações. / Tempol has been shown to protect animals from oxidative stress conditions. Tempol\'s protective mechanisms against reactive oxygen species have been extensively studied but its interactions with reactive nitrogen species remain little explored. Recently, we proposed that tempol diverts peroxynitrite/CO2 mediated phenol nitration to nitrosation by reacting with CO3•‾ to produce tempol oxamonium cation that oxidizes peroxynitrite to O2 and •NO. The latter produces a nitrosating species by reacting with peroxynitrite-derived •NO2 [Bonini et al. (2002) Chem. Res. Toxicol. 15: 506]. To examine wether this mechanism operates in biological environments, we studied the effects of tempol on peroxynitrite/CO2 reactivity towards a protein, BSA, and cells, macrophages. Tempol\'s effects were dependent on its own and BSA-cys concentration. Although not a true catalyst, it inhibited BSA-cys oxydation (20-50%) and BSA-tyr nitration (70-90%) while increasing BSA-cys nitrosation (200-400%). In the case of macrophages treated with peroxynitrite/CO2, tempol also inhibited protein-tyr nitration (90%) and increased protein-cys nitrosation (300%). Then, under physiological conditions, a substoichiometric amount of tempol is able to divert peroxynitrite-derived radicais reactivity from protein-cys oxidation and protein-tyr nitration to protein-cys nitrosation. This may be the mechanism by wich tempol inhibits injury in inflammatory conditions.
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Réaction de nitration en continu pour la synthèse d’un principe actif pharmaceutique : fonctionnalisation d’hétérocycles borés obtenus par borylation électrophile / Continuous nitration reaction for the synthesis of an active pharmaceutical ingredient : functionnalisation of boron heterocycles synthetised by electrophilic borylationCharbonnier, Jean-Baptiste 08 June 2018 (has links)
La fluidique est un outil offrant des avantages industriels notamment en termes de sécurité grâce à un meilleur contrôle thermique mais aussi une diminution des risques due à un engagement de volumes faibles. Cette technologie permet des réactions chimiques plus efficaces grâce à un système plus homogène qui impacte les rendements, la sélectivité ou encore la quantité de réactifs nécessaire. Aujourd’hui, la production de principes actifs pharmaceutiques est réalisée majoritairement en procédé batch. Ainsi, dans une première partie, la microfluidique a été appliquée à la synthèse d’un principe actif pharmaceutique. Les diverses étapes réactionnelles ainsi que les paramètres physiques du système ont été optimisés avec l’utilisation de micromélangeurs. Un procédé multi-étapes a été développé avec une productivité atteignant 100 g.h-1. Des productions ont été réalisées validant les tests préliminaires ainsi que la possibilité de production du principe actif pharmaceutique en continu.Les dérivés du bore sont quant à eux des intermédiaires réactionnels couramment utilisés pour leurs réactivités en synthèse organique. Ainsi, dans une seconde partie, la réaction de borylation électrophile a été étudiée, et plus spécifiquement la synthèse des oxa et des azaborinines grâce au complexe diisopropylamine borane (DIPAB) utilisé comme agent de borylation. Ces dernières molécules ont ensuite été fonctionnalisées grâce à des réactions d’oxydation, d’amination ou d’halogénation. / Fluidic devices offer industrial advantages especially in terms of security due to a better thermal control and a minimization of risks with lower volumes involved. This technology increases chemical reaction efficiencies thanks to a more homogeneous system which affects yields, selectivity and reagent quantities. Nowadays, pharmaceutical active principles are still predominantly produced using batch. Thus, in a first part, microfluidic has been applied to the synthesis of an active pharmaceutical ingredient. Each reaction step as well as the physical parameters of the system have been optimized by using a micromixer. A multi-step process has been developed with a productivity up to 100 g.h-1. Productions have been realized thereby validating preliminary studies including the possibility to produce the active pharmaceutical ingredient.Boron derivatives are chemical intermediates commonly used in organic synthesis for their reactivity. In a second part, electrophilic borylation reaction has been studied with the synthesis of oxa and azaborinins compounds as targets and the use of diisopropylamine borane complex (DIPAB) as a borylation agent. These molecules have then been functionalized through the use of oxidation, amination or halogenation reactions.
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Nitrierung von Aromaten mit SalzhydratschmelzenBok, Frank 06 July 2010 (has links) (PDF)
Gegenstand der vorliegenden Arbeit war es, die Grundlagen für ein mögliches technisches Verfahren zur Aromatennitrierung mit Salzhydratschmelzen (M(NO3)3 · n H2O, M = Fe, Cr, Bi, In, Al; n = 4 - 9) zu untersuchen. Es sollte geklärt werden, ob Toluol quantitativ zu Dinitrotoluol bzw. Benzol zu Nitrobenzol umgesetzt werden kann. In Screening-Versuchen wurden geeignete, nitrierend wirkende Salzhydrate ermittelt, sowie Wege untersucht, die Reaktivität der eingesetzten Salzhydratschmelzen durch Variation von Wasser- bzw. Säuregehalt, Durchmischung, verschiedenen Schmelzenzusätzen bzw. Reaktionstemperatur zu steigern. Das entstehende Verhältnis der Isomeren der Mono- und Dinitrierung wurde hinsichtlich einer möglichen Beeinflussung untersucht. Das Spektrum an Nebenprodukten wurde bestimmt, sowie Möglichkeiten aufgezeigt, diese zu vermeiden. Dabei konnte gezeigt werden, dass im Gegensatz zum etablierten Mischsäureverfahren beim Einsatz von Salzhydratschmelzen keine kresolischen Nebenprodukte gebildet werden. Weiterhin wurden Möglichkeiten zur Präparation wasserarmer Salzhydratschmelzen durch thermische Entwässerung bzw. Reaktion mit flüssigem N2O4 untersucht, die Löslichkeit der isomeren Zwischen- und Endprodukte in der Salzhydratschmelze bestimmt sowie das thermische Verhalten von Dinitrotoluol in Gegenwart der Salze betrachtet.
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Efeitos do tempol sobre a interação entre peroxinitrito/CO2 com albumina e macrófagos: inibição da nitração de tirosinas e da oxidação de cisteínas e amplificação da nitrosação de cisteínas / Effects of tempol on the interaction between peroxynitrite/CO2 with albumin and macrophages: Inhibition of the nitration of tyrosine and oxidation of cysteine and amplification of cysteine nitrosationDenise de Castro Fernandes 19 February 2004 (has links)
O tempol (TP) tem se mostrado um eficiente protetor em modelos inflamatórios. Os mecanismos de proteção contra espécies reativas de oxigênio foi bastante estudado mas sua interação com espécies reativas de nitrogênio ainda permanece pouco explorada. Recentemente, propusemos que o TP re-direciona a nitração de fenol mediada por peroxintrito (PN)/CO2 para nitrosação, pela sua reação com o radical CO3•‾. O produto desta reação, o cátion oxamônio, oxidaria PN para O2 e •NO. Este último produziria uma espécie nitrosante (N2O3) pela reação com o radical derivado do PN, •NO2 [Bonini e col. (2002) Chem. Res. Tox. 15: 506]. Para examinar se este mecanismo poderia operar in vivo, estudamos os efeitos do TP na reatividade do PN/CO2 frente a albumina (BSA) e macrófagos. Os efeitos do TP se apresentaram dependentes de sua concentração e da concentração de Cys. Apesar do TP não se mostrar catalítico, ele inibiu a oxidação de Cys (20-50%) e nitração de Tyr (70-90%) da BSA e aumentou a nitrosação de Cys (200-400%). No caso dos macrófagos tratados com PN/CO2, o tempol também inibiu a nitração (90%) e aumentou a nitrosação (300%). Assim, em condições fisiológicas, concentrações sub-estequiométricas de TP seriam capazes de redirecionar a reatividade dos radicais derivados PN, de oxidação de Cys proteica e nitração de Tyr para nitrosação de Cys. Desta forma, o TP poderia inibir a injúria em inflamações. / Tempol has been shown to protect animals from oxidative stress conditions. Tempol\'s protective mechanisms against reactive oxygen species have been extensively studied but its interactions with reactive nitrogen species remain little explored. Recently, we proposed that tempol diverts peroxynitrite/CO2 mediated phenol nitration to nitrosation by reacting with CO3•‾ to produce tempol oxamonium cation that oxidizes peroxynitrite to O2 and •NO. The latter produces a nitrosating species by reacting with peroxynitrite-derived •NO2 [Bonini et al. (2002) Chem. Res. Toxicol. 15: 506]. To examine wether this mechanism operates in biological environments, we studied the effects of tempol on peroxynitrite/CO2 reactivity towards a protein, BSA, and cells, macrophages. Tempol\'s effects were dependent on its own and BSA-cys concentration. Although not a true catalyst, it inhibited BSA-cys oxydation (20-50%) and BSA-tyr nitration (70-90%) while increasing BSA-cys nitrosation (200-400%). In the case of macrophages treated with peroxynitrite/CO2, tempol also inhibited protein-tyr nitration (90%) and increased protein-cys nitrosation (300%). Then, under physiological conditions, a substoichiometric amount of tempol is able to divert peroxynitrite-derived radicais reactivity from protein-cys oxidation and protein-tyr nitration to protein-cys nitrosation. This may be the mechanism by wich tempol inhibits injury in inflammatory conditions.
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Nitrierung von Aromaten mit SalzhydratschmelzenBok, Frank 18 June 2010 (has links)
Gegenstand der vorliegenden Arbeit war es, die Grundlagen für ein mögliches technisches Verfahren zur Aromatennitrierung mit Salzhydratschmelzen (M(NO3)3 · n H2O, M = Fe, Cr, Bi, In, Al; n = 4 - 9) zu untersuchen. Es sollte geklärt werden, ob Toluol quantitativ zu Dinitrotoluol bzw. Benzol zu Nitrobenzol umgesetzt werden kann. In Screening-Versuchen wurden geeignete, nitrierend wirkende Salzhydrate ermittelt, sowie Wege untersucht, die Reaktivität der eingesetzten Salzhydratschmelzen durch Variation von Wasser- bzw. Säuregehalt, Durchmischung, verschiedenen Schmelzenzusätzen bzw. Reaktionstemperatur zu steigern. Das entstehende Verhältnis der Isomeren der Mono- und Dinitrierung wurde hinsichtlich einer möglichen Beeinflussung untersucht. Das Spektrum an Nebenprodukten wurde bestimmt, sowie Möglichkeiten aufgezeigt, diese zu vermeiden. Dabei konnte gezeigt werden, dass im Gegensatz zum etablierten Mischsäureverfahren beim Einsatz von Salzhydratschmelzen keine kresolischen Nebenprodukte gebildet werden. Weiterhin wurden Möglichkeiten zur Präparation wasserarmer Salzhydratschmelzen durch thermische Entwässerung bzw. Reaktion mit flüssigem N2O4 untersucht, die Löslichkeit der isomeren Zwischen- und Endprodukte in der Salzhydratschmelze bestimmt sowie das thermische Verhalten von Dinitrotoluol in Gegenwart der Salze betrachtet.
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3-Nitrotyrosine as an indicator of the disease state claudicationDean, Sadie January 2009 (has links)
3-nitrotyrosine (3NT), a stable end product arising from the interaction of proteins and reactive nitrogen species such as peroxynitrite, is produced during periods of oxidative stress. 3NT is, therefore, of interest as a potential biomarker in a variety of disease states where oxidative stress is known to be involved in the pathology, for example intermittent claudication. The aim of this thesis was to develop sensitive and specific immunoassays to assess the levels of 3NT in plasma samples from claudicants and to investigate the protein nitration profile. Clinical data and plasma samples were collected from claudicant (n=33) and control (n=6) subjects. Analysis of data confirmed the difficulty of using parameters such as ankle brachial index (ABI) in diagnosis, supporting the need for investigations into potential biomarkers. Development of indirect and competitive ELISAs using electrochemically nitrated bovine serum albumin as the standard revealed that the detection of 3NT was dependent on the antibody being able to access the 3NT-residues within the protein. Various denaturing conditions and different types of microtitre plate were utilised during development. Initially the presence of 3NT in claudicant or control whole plasma samples could only be detected using dot blot immunodetection. Affinity purification techniques for the fractionation of the plasma proteins were therefore applied. Subsequently, 3NT-containing plasma proteins were found to be present in all of the claudicant and control samples using the developed competitive ELISA. Proteomic analysis of the 3NT-affinity purified samples, using MALDI-MS and LC-ESI-MS/MS, confirmed the presence of human serum albumin, serotransferrin and apolipoprotein A1 and A2 precursors within those protein bands staining immunopositive for 3NT on SDS-PAGE gels. The identification of apolipoprotein A1 within 3NT-immunopositive bands confirms previous reports suggesting the oxidative modification of HDL may contribute to the link between inflammation and the pathology of atherosclerosis.
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C-terminal tyrosine residue modifications modulate α-synuclein toxicity in yeast as unicellular model for Parkinson´s diseaseKleinknecht, Alexandra 30 June 2016 (has links)
No description available.
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Identificação de proteínas de Trypanossoma cruzi modificadas por S-nitrosilação e nitração após adesão com matriz xtracelular / Identification of proteins modified by S-nitrosylation and tyrosine nitration after adhesion of Trypanosoma cruzi to the extracellular matrixPereira, Milton César de Almeida 14 February 2014 (has links)
Óxido nítrico (NO) é um segundo mensageiro biosintetizado a partir de L-Arginina e envolvido em sinalização celular por diferentes mecanismos: ativação da produção de cGMP pela Guanilil Ciclase; regulação de enzimas pela interação com seus centros metálicos; ou pela S-nitrosilação de cisteína e nitração de tirosina, modificações pós-traducionais, capazes de modular a atividade de diversas proteínas. Neste trabalho buscou-se investigar se a interação de Trypanosoma cruzi, o agente etiológico da doença de Chagas, com a matriz extracelular (ECM) era capaz de modular a sinalização por NO em T. cruzi. Tripomastigotas de T. cruzi incubados com ECM apresentaram diminuição na atividade de NOS e menor produção de NO. Da mesma maneira, observou-se, por imunofluorescência indireta e imunoblotting, uma diminuição no padrão geral de S-nitrosilação e nitração de proteínas do parasita incubado com ECM. Além disto, os perfis de proteínas S-nitrosiladas e nitradas foram modificados, predominando a denitrosilação e denitração (de 40 para 22 proteínas nitradas após a adesão a ECM), embora em alguns casos tenha sido observado um aumento de nitração, como em proteínas de citoesqueleto (de 2,5% para 9,1% após adesão). O mesmo padrão foi observado em relação a proteínas nitradas, com diminuição de 48 para 20 proteínas após adesão a ECM e novamente com modificação no percentual de proteínas nitradas pertencentes a processos biológicos distintos, como proteínas relacionadas à síntese proteica (35,4% das proteínas nitradas no grupo controle e apenas 5,0% no grupo incubado com ECM). Apesar do perfil de denitração, algumas classes de proteínas têm aumento no número de alvos nitrados, como proteínas relacionadas a metabolismo (de 18,8% para 35,0%), além de alguns alvos específicos que têm aumento na nitração, como enolase. Em suma, os resultados sugerem que a sinalização intracelular por NO em tripomastigotas de T. cruzi é modulada durante a adesão do parasita a componentes da matrix extracelular, tanto através da via clássica de produção de óxido nítrico, quanto por modificações pós-traducionais induzidas por NO. / Nitric oxide (NO) is a second messenger biosynthesized from L-Arginine and involved in cell signaling by different mechanisms: activation of cGMP production by guanilyl cyclase; regulation of enzymes by interaction with their metallic centers; or by S-nitrosylation of cysteine and nitration of tyrosine, posttranslational modifications capable of modulating the activity of several proteins. In this work, we sought to investigate whether the interaction between extracellular matrix (ECM) and Trypanosoma cruzi, the etiological agent of Chagas\' disease, was capable of modulating NO signaling in the parasite. Trypomastigotes incubated with ECM presented a decrease in NOS activity and NO production. Accordingly, a decrease in S-nitrosylation and tyrosine nitration of proteins from ECM-incubated parasites was also observed, as evidenced by indirect immunofluorescence and immunoblotting. In addition, S-nitrosylated and tyrosine nitrated proteins profiles were modified in ECM-incubated parasites, with an enhancement in protein denytrosylation and denitration. A decrease from 40 to 22 of S-nitrosylated proteins was detected after parasite adhesion to ECM, more evident in some protein groups (as for example 52.5% hypothetical proteins modified in the control group against 36.4% after adhesion). On the other hand, an increase of S-nitrosylation was detected in other groups of proteins, such as cytoskeleton proteins (from 2.5% of total S-nitrosylated proteins to 9.1% after adhesion). The same general pattern was observed in relation to tyrosine-nitrated proteins, with a decrease in the number of modified proteins from 48 to 20 after incubation with ECM, exemplified by those related to protein synthesis, with a contribution of 35.4% in the control group versus 5.0% after treatment with ECM. Despite this general denitration profile, some protein classes have an increase in nitration, such as metabolic proteins (from 18.8% to 35.0%), in addition to some specific targets, such as enolase. Taken together, the results suggest that NO signaling is modulated during adhesion of T. cruzi to components of the extracellular matrix, probably by the classical nitric oxide pathway and by NO-induced post translational modifications.
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Identificação de alvos protéicos com potencial diagnóstico e prognóstico em doença arterial coronária / Identification of protein targets with potential diagnostic and prognostic in coronary artery diseaseSilva, Gabriela Venturini da 15 June 2012 (has links)
Em todo o mundo, milhões de pacientes são atendidos em emergências por apresentarem dor torácica de início aguda, mas apenas uma parcela deve-se a síndrome coronariana aguda (SCA). Em situações como essa é de extrema importância distinguir quando a dor torácica é devido à isquemia do miocárdio, pois esta é de alto risco e o início do tratamento deve ser imediato. Novos biomarcadores são necessários para auxiliar no diagnóstico e conduta clínica a ser tomada diante de situações de emergência como esta. Recentemente a quantificação de troponinas através de ensaios ultrassensíveis tem sido amplamente utilizado para diagnósticos e prognóstico de isquemia cardíaca, porém esses ensaios não tiveram seus valores de referências estabelecidos e validados para diversas situações clínicas. O presente estudo identificou a troponina I cardíaca nitrada como um novo biomarcador para isquemia cardíaca. Através de experimentos de imunoluorecência, foi possível colocalizar a marcação de troponina I cardíaca e nitrotirosina em modelos celulares e murinos de isquemia cardíaca, sugerindo assim que a troponina I cardíaca é nitrada. A partir do soro de modelos porcinos de isquemia, foi realizado o enriquecimento de proteínas nitradas por imunoprecipitação seguido da identificação da troponina I cardíaca por western blot. Dessa maneira foi possível identificar a troponina I cardíaca nitrada no soro poucos minutos após o evento x isquêmico, a qual permaneceu circulante por até 24 horas. Nessas mesmas amostras outros biomarcadores de isquemia como CKMB, Troponina I e Troponina T ultrassensível foram dosados e nenhum marcador de elevou após a isquemia cardíaca seguida de reperfusão. A troponina I cardíaca nitrada foi caracterizada por espectrometria de massas. Esse proteína é um potencial marcador circulante sensível para o diagnóstico e prognóstico precoce de isquemia cardíaca com ou sem necrose do miocárdio / Worldwide, millions of patients are treated in emergencies because they had acute-onset chest pain, but only a portion is due to coronary syndrome. In situations like this is extremely important to distinguish when the chest pain is due to myocardial ischemia, as this is high risk and initiation of treatment should be immediate. New biomarkers are needed to assist clinical decision-making in ACS. Recently, the quantification of ultra-sensitive tests for troponins has been widely used for diagnosis and prognosis of myocardial ischemia, however the reference values was not well validated and established for different subjects groups. The present study identified the nitrated cardiac troponin I as a novel biomarker of cardiac ischemia. We performed immunofluorescence colocalization marking of cardiac troponin I and nitrotyrosine in cell and rat model of cardiac ischemia, suggesting that cardiac troponin I is a nitrated protein. From serum of porcine models cardiac ischemia was made enrichment of nitrated proteins by immunoprecipitation with anti-nitrotyrosine followed by detection of cardiac troponin I by western blot. It was possible to identify the cardiac troponin I in serum nitrated few minutes after the ischemic event, which remains current for up to 24 hours. In these samples, other markers of cardiac ischemia such as CK-MB, troponin I and ultra-sensitive troponin T did not increase after ischemia followed by reperfusion. Nitrated cardiac troponin I was characterized by MS/MS. The xii nitrated cardiac troponin I is a potential circulating marker sensitive for the diagnosis and prognosis for early cardiac ischemia with or without myocardial necrosis
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Identificação de alvos protéicos com potencial diagnóstico e prognóstico em doença arterial coronária / Identification of protein targets with potential diagnostic and prognostic in coronary artery diseaseGabriela Venturini da Silva 15 June 2012 (has links)
Em todo o mundo, milhões de pacientes são atendidos em emergências por apresentarem dor torácica de início aguda, mas apenas uma parcela deve-se a síndrome coronariana aguda (SCA). Em situações como essa é de extrema importância distinguir quando a dor torácica é devido à isquemia do miocárdio, pois esta é de alto risco e o início do tratamento deve ser imediato. Novos biomarcadores são necessários para auxiliar no diagnóstico e conduta clínica a ser tomada diante de situações de emergência como esta. Recentemente a quantificação de troponinas através de ensaios ultrassensíveis tem sido amplamente utilizado para diagnósticos e prognóstico de isquemia cardíaca, porém esses ensaios não tiveram seus valores de referências estabelecidos e validados para diversas situações clínicas. O presente estudo identificou a troponina I cardíaca nitrada como um novo biomarcador para isquemia cardíaca. Através de experimentos de imunoluorecência, foi possível colocalizar a marcação de troponina I cardíaca e nitrotirosina em modelos celulares e murinos de isquemia cardíaca, sugerindo assim que a troponina I cardíaca é nitrada. A partir do soro de modelos porcinos de isquemia, foi realizado o enriquecimento de proteínas nitradas por imunoprecipitação seguido da identificação da troponina I cardíaca por western blot. Dessa maneira foi possível identificar a troponina I cardíaca nitrada no soro poucos minutos após o evento x isquêmico, a qual permaneceu circulante por até 24 horas. Nessas mesmas amostras outros biomarcadores de isquemia como CKMB, Troponina I e Troponina T ultrassensível foram dosados e nenhum marcador de elevou após a isquemia cardíaca seguida de reperfusão. A troponina I cardíaca nitrada foi caracterizada por espectrometria de massas. Esse proteína é um potencial marcador circulante sensível para o diagnóstico e prognóstico precoce de isquemia cardíaca com ou sem necrose do miocárdio / Worldwide, millions of patients are treated in emergencies because they had acute-onset chest pain, but only a portion is due to coronary syndrome. In situations like this is extremely important to distinguish when the chest pain is due to myocardial ischemia, as this is high risk and initiation of treatment should be immediate. New biomarkers are needed to assist clinical decision-making in ACS. Recently, the quantification of ultra-sensitive tests for troponins has been widely used for diagnosis and prognosis of myocardial ischemia, however the reference values was not well validated and established for different subjects groups. The present study identified the nitrated cardiac troponin I as a novel biomarker of cardiac ischemia. We performed immunofluorescence colocalization marking of cardiac troponin I and nitrotyrosine in cell and rat model of cardiac ischemia, suggesting that cardiac troponin I is a nitrated protein. From serum of porcine models cardiac ischemia was made enrichment of nitrated proteins by immunoprecipitation with anti-nitrotyrosine followed by detection of cardiac troponin I by western blot. It was possible to identify the cardiac troponin I in serum nitrated few minutes after the ischemic event, which remains current for up to 24 hours. In these samples, other markers of cardiac ischemia such as CK-MB, troponin I and ultra-sensitive troponin T did not increase after ischemia followed by reperfusion. Nitrated cardiac troponin I was characterized by MS/MS. The xii nitrated cardiac troponin I is a potential circulating marker sensitive for the diagnosis and prognosis for early cardiac ischemia with or without myocardial necrosis
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