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1.
Nat Commun ; 11(1): 4907, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999289

RESUMO

Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.


Assuntos
Materiais Biomiméticos/administração & dosagem , Matriz Extracelular/química , Neoplasias/terapia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/efeitos da radiação , Materiais Biomiméticos/química , Materiais Biomiméticos/efeitos da radiação , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Quimiorradioterapia/métodos , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos da radiação , Feminino , Fibrinogênio/administração & dosagem , Fibrinogênio/química , Fibrinogênio/efeitos da radiação , Géis , Humanos , Injeções Intravenosas , Metabolômica , Camundongos , Neoplasias/metabolismo , Trombina/administração & dosagem , Trombina/química , Trombina/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas
2.
PLoS One ; 15(8): e0237024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764787

RESUMO

BACKGROUND: Thrombin, a key enzyme of the clotting system, is involved in thrombus formation, platelet activation, and atherosclerosis, thereby possessing a central role in the pathogenesis of ischemic heart disease. Studies have shown an association between thrombin generation (TG) and cardiovascular morbidity and mortality, but results have been equivocal. Our aim was to study the predictive ability of TG assay in evaluating coronary stenosis severity. METHODS: In this prospective study we recruited patients with acute coronary syndrome (ACS) or acute chest pain (without evidence of myocardial injury) planned for coronary angiography. Thrombin generation was evaluated by Calibrated Automated Thrombogram (CAT) prior to angiography. Primary end points were significant coronary stenosis and the Syntax I score evaluated by coronary angiography. RESULTS: From April 2018 through September 2019, we recruited 128 patients. In the primary analysis there was no significant association between TG and significant coronary stenosis nor between TG and syntax I score, however, there was a positive correlation between peak height and troponin peak (Spearman correlation coefficient 0.194, P-value = 0.035). In sub-group analysis, the chest pain group bare no association between TG and coronary stenosis. In unstable angina group there was an association between peak height and significant coronary stenosis (P-value = 0.029), and in non ST-elevation myocardial infarction group, TG values possessed a relatively good predictive ability of significant coronary stenosis (area under the receiver operating characteristic curve of ~65%) and a positive correlation between both lag time and ttpeak with the syntax I score was noticed (Spearman correlation coefficient 0.31, P-value = 0.099 and Spearman correlation coefficient 0.37, P-value = 0.045 respectively). CONCLUSION: In patients with acute chest pain, TG values, evaluated by CAT, do not predict severity of coronary stenosis, nor do they possess prognostic value. Yet, in ACS patients, TG may have the ability to predict coronary disease severity.


Assuntos
Doença da Artéria Coronariana/sangue , Trombina/biossíntese , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Adulto , Idoso , Angina Instável/sangue , Angina Instável/diagnóstico por imagem , Biomarcadores/sangue , Dor no Peito/sangue , Dor no Peito/diagnóstico por imagem , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/sangue , Estenose Coronária/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/sangue , Infarto do Miocárdio sem Supradesnível do Segmento ST/sangue , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico por imagem , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença
4.
Proc Natl Acad Sci U S A ; 117(29): 16782-16789, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32641511

RESUMO

DNA-encoded chemical libraries are collections of compounds individually coupled to unique DNA tags serving as amplifiable identification barcodes. By bridging split-and-pool combinatorial synthesis with the ligation of unique encoding DNA oligomers, million- to billion-member libraries can be synthesized for use in hundreds of healthcare target screens. Although structural diversity and desirable molecular property ranges generally guide DNA-encoded chemical library design, recent reports have highlighted the utility of focused DNA-encoded chemical libraries that are structurally biased for a class of protein targets. Herein, a protease-focused DNA-encoded chemical library was designed that utilizes chemotypes known to engage conserved catalytic protease residues. The three-cycle library features functional moieties such as guanidine, which interacts strongly with aspartate of the protease catalytic triad, as well as mild electrophiles such as sulfonamide, urea, and carbamate. We developed a DNA-compatible method for guanidinylation of amines and reduction of nitriles. Employing these optimized reactions, we constructed a 9.8-million-membered DNA-encoded chemical library. Affinity selection of the library with thrombin, a common protease, revealed a number of enriched features which ultimately led to the discovery of a 1 nM inhibitor of thrombin. Thus, structurally focused DNA-encoded chemical libraries have tremendous potential to find clinically useful high-affinity hits for the rapid discovery of drugs for targets (e.g., proteases) with essential functions in infectious diseases (e.g., severe acute respiratory syndrome coronavirus 2) and relevant healthcare conditions (e.g., male contraception).


Assuntos
DNA/química , DNA/metabolismo , Descoberta de Drogas , Biblioteca Gênica , Inibidores de Proteases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Trombina/antagonistas & inibidores , Técnicas de Química Combinatória , Humanos , Inibidores de Proteases/química , Bibliotecas de Moléculas Pequenas/química
5.
PLoS One ; 15(7): e0235392, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726315

RESUMO

Platelets upregulate the generation of thrombin and reinforce the fibrin clot which increases the incidence risk of venous thromboembolism (VTE). However, the role of platelets in the pathogenesis of venous cardiovascular diseases remains hard to quantify. An experimentally validated model of thrombin generation dynamics is formulated. The model predicts that a high platelet count increases the peak value of generated thrombin as well as the endogenous thrombin potential (ETP) as reported in experimental data. To investigate the effects of platelets density, shear rate, and wound size on the initiation of blood coagulation, we calibrate a previously developed model of venous thrombus formation and implement it in 3D using a novel cell-centered finite-volume solver. We conduct numerical simulations to reproduce in vitro experiments of blood coagulation in microfluidic capillaries. Then, we derive a reduced one-equation model of thrombin distribution from the previous model under simplifying hypotheses and we use it to determine the conditions of clotting initiation on the platelet count, the shear rate, and the plasma composition. The initiation of clotting also exhibits a threshold response to the size of the wounded region in good agreement with the reported experimental findings.


Assuntos
Coagulação Sanguínea/fisiologia , Plaquetas/fisiologia , Modelos Teóricos , Contagem de Plaquetas/métodos , Testes de Coagulação Sanguínea , Plaquetas/metabolismo , Fibrina/metabolismo , Humanos , Agregação Plaquetária/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Resistência ao Cisalhamento/fisiologia , Trombina/metabolismo , Tromboplastina/metabolismo , Trombose/metabolismo , Trombose/fisiopatologia , Veias/metabolismo , Veias/fisiologia
6.
Food Chem ; 332: 127384, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615384

RESUMO

Dairy polar lipids (PL) seem to exhibit antiplatelet effects. However, it is not known what molecular species may be responsible. In this study, we confirmed using C30 reversed-phase (C30RP) ultra-high-performance liquid chromatography (UHPLC) coupled to high resolution accurate mass tandem mass spectrometry (HRAM-MS/MS) that fermentation of yoghurts from ovine milk using specific starter cultures altered the PL composition. These lipid alterations occurred concomitant with increased antithrombotic properties of the yoghurts PL fractions against platelet-activating factor (PAF) and thrombin-induced platelet aggregation. Specifically, elevation in phosphatidylethanolamine (PE), sphingomyelin (SM), phosphatidylcholine (PC) and their molecular species were observed following yoghurt fermentation. Furthermore, PC(18:0/18:1), PE(18:1/18:2), SM(d18:0/22:0) and several other molecular species were significantly inversely correlated with the inhibition of PAF and thrombin. These molecular species were abundant in the most bioactive yoghurts fermented by S. thermophilus and L. acidophilus, which suggest that fermentation by these microorganisms increases the antithrombotic properties of ovine milk PL.


Assuntos
Lipídeos/análise , Leite/metabolismo , Inibidores da Agregação de Plaquetas/análise , Iogurte/análise , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cromatografia Líquida de Alta Pressão , Fermentação , Lipídeos/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/farmacologia , Ovinos , Esfingomielinas/metabolismo , Espectrometria de Massas em Tandem , Trombina/farmacologia
7.
Vasc Endovascular Surg ; 54(7): 633-637, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32648523

RESUMO

Endovascular aneurysm repair (EVAR) has quickly outpaced open treatment of infrarenal abdominal aortic aneurysm (AAA) and iliac artery aneurysms, relegating most open AAA repair for either young patients with long life expectancy or patients with extreme anatomic constraints. Typically, open repair involves opening the aneurysm sac with suture ligation of back-bleeding vessels. However, in situations where an aortobifemoral repair is performed, proximal and distal ligation can be performed leaving behind a "remnant" aorta and iliac arteries. Usually, major palpable vessels are ligated and small lumbars spontaneously thrombose. However, failure of this to occur can lead to a rare situation in which there is persistent filling of a remnant aorta and aneurysm sac leading to a situation similar to a type II endoleak after EVAR. Typically, this leak has been repaired by open ligation. We present a technique for endovascular coiling and thrombin injection to correct a "type II endoleak" from a back-bleeding lumbar artery after open aortoiliac and femoral aneurysm repair.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Embolização Terapêutica , Endoleak/terapia , Procedimentos Endovasculares , Trombina/administração & dosagem , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , Embolização Terapêutica/instrumentação , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Procedimentos Endovasculares/instrumentação , Humanos , Injeções Intra-Arteriais , Masculino , Resultado do Tratamento
8.
Arterioscler Thromb Vasc Biol ; 40(9): 2127-2142, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32698684

RESUMO

OBJECTIVE: Atherothrombosis occurs upon rupture of an atherosclerotic plaque and leads to the formation of a mural thrombus. Computational fluid dynamics and numerical models indicated that the mechanical stress applied to a thrombus increases dramatically as a thrombus grows, and that strong inter-platelet interactions are essential to maintain its stability. We investigated whether GPVI (glycoprotein VI)-mediated platelet activation helps to maintain thrombus stability by using real-time video-microscopy. Approach and Results: We showed that GPVI blockade with 2 distinct Fab fragments promoted efficient disaggregation of human thrombi preformed on collagen or on human atherosclerotic plaque material in the absence of thrombin. ACT017-induced disaggregation was achieved under arterial blood flow conditions, and its effect increased with wall shear rate. GPVI regulated platelet activation within a growing thrombus as evidenced by the loss in thrombus contraction when GPVI was blocked, and the absence of the disaggregating effect of an anti-GPVI agent when the thrombi were fully activated with soluble agonists. The GPVI-dependent thrombus stabilizing effect was further supported by the fact that inhibition of any of the 4 key immunoreceptor tyrosine-based motif signalling molecules, src-kinases, Syk, PI3Kß, or phospholipase C, resulted in kinetics of thrombus disaggregation similar to ACT017. The absence of ACT017-induced disaggregation of thrombi from 2 afibrinogenemic patients suggests that the role of GPVI requires interaction with fibrinogen. Finally, platelet disaggregation of fibrin-rich thrombi was also promoted by ACT017 in combination with r-tPA (recombinant tissue plasminogen activator). CONCLUSIONS: This work identifies an unrecognized role for GPVI in maintaining thrombus stability and suggests that targeting GPVI could dissolve platelet aggregates with a poor fibrin content.


Assuntos
Afibrinogenemia/sangue , Plaquetas/efeitos dos fármacos , Fibrinogênio/metabolismo , Fragmentos Fab das Imunoglobulinas/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Glicoproteínas da Membrana de Plaquetas/antagonistas & inibidores , Trombose/tratamento farmacológico , Afibrinogenemia/diagnóstico , Afibrinogenemia/genética , Plaquetas/metabolismo , Simulação por Computador , Fibrinogênio/genética , Fibrinolíticos/farmacologia , Humanos , Cinética , Microscopia de Vídeo , Modelos Biológicos , Glicoproteínas da Membrana de Plaquetas/metabolismo , Transdução de Sinais , Estresse Mecânico , Trombina/metabolismo , Trombose/sangue , Trombose/diagnóstico , Trombose/genética
9.
Eur J Vasc Endovasc Surg ; 60(3): 469-478, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32620348

RESUMO

OBJECTIVE: In vascular and cardiac surgery, the ability to maintain haemostasis and seal haemorrhagic tissues is key. Fibrin and thrombin based sealants were introduced as a means to prevent or halt bleeding during surgery. Whether fibrin and thrombin sealants affect surgical outcomes is poorly established. A systematic review and meta-analysis was performed to examine the impact of fibrin or thrombin sealants on patient outcomes in vascular and cardiac surgery. DATA SOURCES: Cochrane CENTRAL, Embase, and MEDLINE, as well as trial registries, conference abstracts, and reference lists of included articles were searched from inception to December 2019. REVIEW METHODS: Studies comparing the use of fibrin or thrombin sealant with either an active (other haemostatic methods) or standard surgical haemostatic control in vascular and cardiac surgery were searched for. The Cochrane risk of bias tool and the ROBINS-I tool (Risk Of Bias In Non-randomised Studies - of Interventions) were used to assess the risk of bias of the included randomised and non-randomised studies; quality of evidence was assessed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Two reviewers screened studies, assessed risk of bias, and extracted data independently and in duplicate. Data from included trials were pooled using a random effects model. RESULTS: Twenty-one studies (n = 7 622 patients) were included: 13 randomised controlled trials (RCTs), five retrospective, and three prospective cohort studies. Meta-analysis of the RCTs showed a statistically significant decrease in the volume of blood lost (mean difference 120.7 mL, in favour of sealant use [95% confidence interval {CI} -150.6 - -90.7; p < .001], moderate quality). Time to haemostasis was also shown to be reduced in patients receiving sealant (mean difference -2.5 minutes [95% CI -4.0 - -1.1; p < .001], low quality). Post-operative blood transfusions, re-operation due to bleeding, and 30 day mortality were not significantly different for either RCTs or observational data. CONCLUSION: The use of fibrin and thrombin sealants confers a statistically significant but clinically small reduction in blood loss and time to haemostasis; it does not reduce blood transfusion. These Results may support selective rather than routine use of fibrin and thrombin sealants in vascular and cardiac surgery.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Procedimentos Cirúrgicos Cardíacos , Adesivo Tecidual de Fibrina/administração & dosagem , Hemostasia , Hemostáticos/administração & dosagem , Hemorragia Pós-Operatória/prevenção & controle , Trombina/administração & dosagem , Adesivos Teciduais/administração & dosagem , Procedimentos Cirúrgicos Vasculares , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Adesivo Tecidual de Fibrina/efeitos adversos , Hemostáticos/efeitos adversos , Humanos , Hemorragia Pós-Operatória/etiologia , Fatores de Risco , Trombina/efeitos adversos , Fatores de Tempo , Adesivos Teciduais/efeitos adversos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos
10.
Am J Hum Genet ; 107(2): 211-221, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32649856

RESUMO

Dual antiplatelet therapy reduces ischemic events in cardiovascular disease, but it increases bleeding risk. Thrombin receptors PAR1 and PAR4 are drug targets, but the role of thrombin in platelet aggregation remains largely unexplored in large populations. We performed a genome-wide association study (GWAS) of platelet aggregation in response to full-length thrombin, followed by clinical association analyses, Mendelian randomization, and functional characterization including iPSC-derived megakaryocyte and platelet experiments. We identified a single sentinel variant in the GRK5 locus (rs10886430-G, p = 3.0 × 10-42) associated with increased thrombin-induced platelet aggregation (ß = 0.70, SE = 0.05). We show that disruption of platelet GRK5 expression by rs10886430-G is associated with enhanced platelet reactivity. The proposed mechanism of a GATA1-driven megakaryocyte enhancer is confirmed in allele-specific experiments. Utilizing further data, we demonstrate that the allelic effect is highly platelet- and thrombin-specific and not likely due to effects on thrombin levels. The variant is associated with increased risk of cardiovascular disease outcomes in UK BioBank, most strongly with pulmonary embolism. The variant associates with increased risk of stroke in the MEGASTROKE, UK BioBank, and FinnGen studies. Mendelian randomization analyses in independent samples support a causal role for rs10886430-G in increasing risk for stroke, pulmonary embolism, and venous thromboembolism through its effect on thrombin-induced platelet reactivity. We demonstrate that G protein-coupled receptor kinase 5 (GRK5) promotes platelet activation specifically via PAR4 receptor signaling. GRK5 inhibitors in development for the treatment of heart failure and cancer could have platelet off-target deleterious effects. Common variants in GRK5 may modify clinical outcomes with PAR4 inhibitors, and upregulation of GRK5 activity or signaling in platelets may have therapeutic benefits.


Assuntos
Plaquetas/fisiologia , Doenças Cardiovasculares/genética , Receptores de Trombina/genética , Transdução de Sinais/genética , Trombina/genética , Alelos , Embolia/genética , Feminino , Estudo de Associação Genômica Ampla/métodos , Insuficiência Cardíaca/genética , Humanos , Pulmão/fisiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Ativação Plaquetária/genética , Agregação Plaquetária/genética , Receptor PAR-1/genética , Acidente Vascular Cerebral/genética
11.
Paediatr Respir Rev ; 35: 20-24, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653469

RESUMO

Since the initial description in 2019, the novel coronavirus SARS-Cov-2 infection (COVID-19) pandemic has swept the globe. The most severe form of the disease presents with fever and shortness of breath, which rapidly deteriorates to respiratory failure and acute lung injury (ALI). COVID-19 also presents with a severe coagulopathy with a high rate of venous thromboembiolism. In addition, autopsy studies have revealed co-localized thrombosis and inflammation, which is the signature of thromboinflammation, within the pulmonary capillary vasculature. While the majority of published data is on adult patients, there are parallels to pediatric patients. In our experience as a COVID-19 epicenter, children and young adults do develop both the coagulopathy and the ALI of COVID-19. This review will discuss COVID-19 ALI from a hematological perspective with discussion of the distinct aspects of coagulation that are apparent in COVID-19. Current and potential interventions targeting the multiple thromboinflammatory mechanisms will be discussed.


Assuntos
Lesão Pulmonar Aguda/sangue , Infecções por Coronavirus/sangue , Inflamação/sangue , Pneumonia Viral/sangue , Trombose/sangue , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/fisiopatologia , Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Betacoronavirus , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/imunologia , Transtornos da Coagulação Sanguínea/fisiopatologia , Capilares/imunologia , Capilares/fisiopatologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/fisiopatologia , Endotélio Vascular/imunologia , Endotélio Vascular/fisiopatologia , Inibidores do Fator Xa/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/fisiopatologia , Pandemias , Ativação Plaquetária , Inibidores da Agregação de Plaquetas/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Pneumonia Viral/fisiopatologia , Embolia Pulmonar/sangue , Embolia Pulmonar/imunologia , Embolia Pulmonar/fisiopatologia , Trombina/imunologia , Trombina/metabolismo , Trombose/tratamento farmacológico , Trombose/imunologia , Trombose/fisiopatologia
12.
Molecules ; 25(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: covidwho-436971

RESUMO

The coronavirus disease, COVID-19, caused by the novel coronavirus SARS-CoV-2, which first emerged in Wuhan, China and was made known to the World in December 2019 turned into a pandemic causing more than 126,124 deaths worldwide up to April 16th, 2020. It has 79.5% sequence identity with SARS-CoV-1 and the same strategy for host cell invasion through the ACE-2 surface protein. Since the development of novel drugs is a long-lasting process, researchers look for effective substances among drugs already approved or developed for other purposes. The 3D structure of the SARS-CoV-2 main protease was compared with the 3D structures of seven proteases, which are drug targets, and docking analysis to the SARS-CoV-2 protease structure of thirty four approved and on-trial protease inhibitors was performed. Increased 3D structural similarity between the SARS-CoV-2 main protease, the HCV protease and α-thrombin was found. According to docking analysis the most promising results were found for HCV protease, DPP-4, α-thrombin and coagulation Factor Xa known inhibitors, with several of them exhibiting estimated free binding energy lower than -8.00 kcal/mol and better prediction results than reference compounds. Since some of the compounds are well-tolerated drugs, the promising in silico results may warrant further evaluation for viral anticipation. DPP-4 inhibitors with anti-viral action may be more useful for infected patients with diabetes, while anti-coagulant treatment is proposed in severe SARS-CoV-2 induced pneumonia.


Assuntos
Anticoagulantes/química , Antivirais/química , Betacoronavirus/efeitos dos fármacos , Inibidores da Dipeptidil Peptidase IV/química , Inibidores de Proteases/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Sequência de Aminoácidos , Anticoagulantes/farmacologia , Antivirais/farmacologia , Betacoronavirus/química , Betacoronavirus/enzimologia , Betacoronavirus/genética , Sítios de Ligação , Infecções por Coronavirus/tratamento farmacológico , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Fator Xa/química , Fator Xa/genética , Fator Xa/metabolismo , Hepacivirus/química , Hepacivirus/enzimologia , Hepacivirus/genética , Humanos , Simulação de Acoplamento Molecular , Pandemias , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Homologia Estrutural de Proteína , Especificidade por Substrato , Termodinâmica , Trombina/antagonistas & inibidores , Trombina/química , Trombina/genética , Trombina/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(3): 899-903, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32552955

RESUMO

OBJECTIVE: To investigate the effect of protein kinase A (PKA) activation on aggregation funetion of platelets in vitro. METHODS: The peripheral blood of healthy adults were collected, and the washed platelets were gained from collected peripheral blood. The washed platelets were treated with PKA activator Forskolin, then the platelet aggregation was induced by using Ristocetin, Thrombin, Collagen and ADP respectively, the platelet aggregation level was detected by the platelet aggregator. RESULTS: Compared with the controls, 5 µmol/L forskolin significantly inhibited ADP and collagen-induced platelet aggregation (P<0.001), and showed mild inhibiting effect on Thrombin-induced platelet aggregation (P<0.05). 2.5-10 µmol/L forskolin significantly inhibited ADP and Collagen -induced platelet aggregation (P<0.001); but not showed significantly inhibitory effects on Ristocetin-induced platelet aggregation (P>0.05). CONCLUSION: PKA activation inhibits agonists-induced platelet aggregation.


Assuntos
Plaquetas , Agregação Plaquetária , Proteínas Quinases Dependentes de AMP Cíclico , Humanos , Inibidores da Agregação de Plaquetas , Ristocetina , Trombina
14.
Molecules ; 25(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32485894

RESUMO

The coronavirus disease, COVID-19, caused by the novel coronavirus SARS-CoV-2, which first emerged in Wuhan, China and was made known to the World in December 2019 turned into a pandemic causing more than 126,124 deaths worldwide up to April 16th, 2020. It has 79.5% sequence identity with SARS-CoV-1 and the same strategy for host cell invasion through the ACE-2 surface protein. Since the development of novel drugs is a long-lasting process, researchers look for effective substances among drugs already approved or developed for other purposes. The 3D structure of the SARS-CoV-2 main protease was compared with the 3D structures of seven proteases, which are drug targets, and docking analysis to the SARS-CoV-2 protease structure of thirty four approved and on-trial protease inhibitors was performed. Increased 3D structural similarity between the SARS-CoV-2 main protease, the HCV protease and α-thrombin was found. According to docking analysis the most promising results were found for HCV protease, DPP-4, α-thrombin and coagulation Factor Xa known inhibitors, with several of them exhibiting estimated free binding energy lower than -8.00 kcal/mol and better prediction results than reference compounds. Since some of the compounds are well-tolerated drugs, the promising in silico results may warrant further evaluation for viral anticipation. DPP-4 inhibitors with anti-viral action may be more useful for infected patients with diabetes, while anti-coagulant treatment is proposed in severe SARS-CoV-2 induced pneumonia.


Assuntos
Anticoagulantes/química , Antivirais/química , Betacoronavirus/efeitos dos fármacos , Inibidores da Dipeptidil Peptidase IV/química , Inibidores de Proteases/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Sequência de Aminoácidos , Anticoagulantes/farmacologia , Antivirais/farmacologia , Betacoronavirus/química , Betacoronavirus/enzimologia , Betacoronavirus/genética , Sítios de Ligação , Infecções por Coronavirus/tratamento farmacológico , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Fator Xa/química , Fator Xa/genética , Fator Xa/metabolismo , Hepacivirus/química , Hepacivirus/enzimologia , Hepacivirus/genética , Humanos , Simulação de Acoplamento Molecular , Pandemias , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Homologia Estrutural de Proteína , Especificidade por Substrato , Termodinâmica , Trombina/antagonistas & inibidores , Trombina/química , Trombina/genética , Trombina/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
15.
Phytomedicine ; 75: 153246, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510336

RESUMO

BACKGROUND: It is of utmost significance to choose the bioactive components as quality markers for ensuring the effectiveness of traditional Chinese medicine (TCM). Nonetheless, some markers are able to assess effectively the quality of TCM without considering the pharmacological mechanisms and intrinsic chemical complexities. OBJECTIVE: This underscores the need to discover new and efficient markers which can assess both quality and mechanism of action. Herein, a strategy of bioactive-chemical quality marker combination was proposed to improve the level of the quality control of TCM by metabolomics coupled with chemometrics. METHODS: A four-step plan was followed. Firstly, acquisition of metabolic features and component characterization of different batches of pollen of Typha orientalis C.Presl were performed using UHPLC-Q-TOF/MS. Secondly, the direct inhibitory effects of pollen of T. orientalis on thrombin was assessed by using chromogenic substrate method together with HPLC. Thereafter, bioactive-chemical marker combination associated with anti-thrombin segregation was screened using supervised classifiers. Finally, quantitative assay and prediction-model of selected markers were established for guarantying the quality of pollen of T. orientalis. RESULTS: A total of 22 compounds were annotated based on comparison with previous work from pollen of T. orientalis by UHPLC-Q-TOF/MS. Citric acid and linolenic acid inhibited the thrombin activity with IC50 values, 0.52 ± 0.02 and 0.51 ± 0.02 mg/mL, respectively. A bioactive-chemical marker combination including citric acid, linolenic acid, typhaneoside, and isorhamnetin-3-O-neohesperidoside were discovered and selected as quality markers for evaluation of pollen of T. orientalis according to their capacity for inhibiting thrombin. CONCLUSION: The thrombin-based discovery strategy of bioactive-chemical marker combination was a powerful tool for screening the quality markers for evaluation of pollen of T. orientalis.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/farmacologia , Pólen/química , Trombina/antagonistas & inibidores , Typhaceae/química , Biomarcadores/análise , Biomarcadores Farmacológicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Flavonóis/análise , Glicosídeos/análise , Medicina Tradicional Chinesa/normas , Metabolômica/métodos , Controle de Qualidade , Espectrometria de Massas em Tandem
16.
Arterioscler Thromb Vasc Biol ; 40(8): 1905-1917, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32580633

RESUMO

OBJECTIVE: Remodeling of the extracellular matrix plays a vital role in cardiovascular diseases. Using a mouse model of postnatal ascending aortic aneurysms (termed Fbln4SMKO), we have reported that abnormal mechanosensing led to aneurysm formation in Fbln4SMKO with an upregulation of the mechanosensitive transcription factor, Egr1 (Early growth response 1). However, the role of Egr1 and its upstream regulator(s) in the initiation of aneurysm development and their relationship to an aneurysmal microenvironment are unknown. Approach and Results: To investigate the contribution of Egr1 in the aneurysm development, we deleted Egr1 in Fbln4SMKO mice and generated double knockout mice (DKO, Fbln4SMKO; Egr1-/-). Aneurysms were prevented in DKO mice (42.8%) and Fbln4SMKO; Egr1+/- mice (26%). Ingenuity Pathway Analysis identified PAR1 (protease-activated receptor 1) as a potential Egr1 upstream gene. Protein and transcript levels of PAR1 were highly increased in Fbln4SMKO aortas at postnatal day 1 before aneurysm formed, together with active thrombin and MMP (matrix metalloproteinase)-9, both of which serve as a PAR1 activator. Concordantly, protein levels of PAR1, Egr1, and thrombin were significantly increased in human thoracic aortic aneurysms. In vitro cyclic stretch assays (1.0 Hz, 20% strain, 8 hours) using mouse primary vascular smooth muscle cells induced marked expression of PAR1 and secretion of prothrombin in response to mechanical stretch. Thrombin was sufficient to induce Egr1 expression in a PAR1-dependent manner. CONCLUSIONS: We propose that thrombin, MMP-9, and mechanical stimuli in the Fbln4SMKO aorta activate PAR1, leading to the upregulation of Egr1 and initiation of ascending aortic aneurysms.


Assuntos
Aneurisma da Aorta Torácica/etiologia , Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Proteínas da Matriz Extracelular/fisiologia , Receptor PAR-1/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Proteínas da Matriz Extracelular/deficiência , Feminino , Humanos , Masculino , Metaloproteinase 9 da Matriz/fisiologia , Camundongos , Pessoa de Meia-Idade , Receptor PAR-1/antagonistas & inibidores , Estresse Mecânico , Trombina/farmacologia
17.
Parasitol Res ; 119(6): 1767-1775, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32363441

RESUMO

The hirudin-like factors 3 (HLF3) and 4 (HLF4) belong to a new class of leech-derived factors and are present in specimens of the three European medicinal leeches, Hirudo medicinalis, Hirudo verbana, and Hirudo orientalis, respectively. Here we describe the functional analysis of natural and synthetic variants of HLF3 and HLF4. Whereas the natural variants display only very low or no detectable anti-coagulatory activities, modifications within the N-termini in combination with an exchange of the central globular domain have the potency to greatly enhance the inhibitory effects of respective HLF3 and HLF4 variants on blood coagulation. Our results support previous observations on the crucial importance of all parts (both the N- and C-termini as well as the central globular domains) of hirudin and HLF molecules for thrombin inhibition.


Assuntos
Hirudinas/metabolismo , Sanguessugas/química , Sequência de Aminoácidos , Animais , Coagulação Sanguínea , Hirudinas/química , Hirudinas/genética , Hirudo medicinalis/química , Hirudo medicinalis/genética , Sanguessugas/classificação , Sanguessugas/genética , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Trombina/antagonistas & inibidores
18.
PLoS One ; 15(5): e0233640, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453766

RESUMO

Understanding the coagulation process is critical to developing treatments for trauma and coagulopathies. Clinical studies on tranexamic acid (TXA) have resulted in mixed reports on its efficacy in improving outcomes in trauma patients. The largest study, CRASH-2, reported that TXA improved outcomes in patients who received treatment prior to 3 hours after the injury, but worsened outcomes in patients who received treatment after 3 hours. No consensus has been reached about the mechanism behind the duality of these results. In this paper we use a computational model for coagulation and fibrinolysis to propose that deficiencies or depletions of key anti-fibrinolytic proteins, specifically antiplasmin, a1-antitrypsin and a2-macroglobulin, can lead to worsened outcomes through urokinase-mediated hyperfibrinolysis.


Assuntos
Transtornos da Coagulação Sanguínea/tratamento farmacológico , Ácido Tranexâmico/uso terapêutico , Ativador de Plasminogênio Tipo Uroquinase/genética , Ferimentos e Lesões/tratamento farmacológico , Antifibrinolíticos/uso terapêutico , Coagulação Sanguínea/genética , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/genética , Transtornos da Coagulação Sanguínea/patologia , Simulação por Computador , Fibrina/genética , Tempo de Lise do Coágulo de Fibrina , Fibrinolisina/genética , Fibrinólise/efeitos dos fármacos , Hemorragia/sangue , Hemorragia/tratamento farmacológico , Hemorragia/genética , Humanos , Proteínas de Membrana/genética , Mortalidade , alfa 2-Macroglobulinas Associadas à Gravidez/genética , Trombina/genética , Trombina/metabolismo , Ferimentos e Lesões/sangue , Ferimentos e Lesões/genética , Ferimentos e Lesões/patologia , alfa 1-Antitripsina/genética
19.
Life Sci ; 256: 117853, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470452

RESUMO

AIMS: To investigate the diabetes-protective effect and weight-lowering potential of a novel long-acting triagonist at three metabolically related hormone receptors including glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), glucagon receptors. MAIN METHODS: Triagonist were designed in an iterative manner from native GLP-1, GIP and Glucogan. Main peptide chain (termed TG peptides) and subsequently modified LTG peptides were synthesized via solid phase synthesis. In vitro receptor activity assay was performed to screen the TG peptide with most balanced potency on all three receptors. The in vitro biological activities of modified TG peptides were further investigated by albumin-binding measurement and proteolytic cleavage test. Subsequently, oral glucose tolerance test (OGTT), pharmacokinetic test and chronic study were subjected to the acute and long-term efficacy evaluation of selected fusion peptide, LTG-6. KEY FINDINGS: TG-8 exhibited equally aligned constituent efficacy and supraphysiological potency on corresponding receptor without cross-reactivity. Modified TG-8, termed LTG-6, exerted the great binding affinity for human serum albumin and the enhanced rational controlled-release of TG-8 in vitro. Further OGTT in different gene knockout mice and diabetic mice demonstrated the promising hypoglycemic and insulinotropic abilities of LTG-6. After long-term treatment for 8 weeks, LTG-6 was proved superior to co-agonists to decrease the body weight and %HbA1c, improve reverse dyslipidemia and glycemic control in the DIO models. SIGNIFICANCE: LTG-6, as a newly designed long-acting triagonist, holds potential to correct the obesity related metabolic disorders.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos/farmacologia , Receptores dos Hormônios Gastrointestinais/agonistas , Receptores de Glucagon/agonistas , Animais , Peso Corporal/efeitos dos fármacos , Teste de Tolerância a Glucose , Células HEK293 , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Masculino , Doenças Metabólicas/etiologia , Doenças Metabólicas/prevenção & controle , Camundongos , Camundongos Knockout , Obesidade/complicações , Obesidade/tratamento farmacológico , Peptídeos/química , Ratos , Ratos Sprague-Dawley , Trombina/química
20.
Vasc Endovascular Surg ; 54(6): 532-535, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32452286

RESUMO

Ultrasound-guided thrombin injection (UGTI) has emerged as the first-line treatment for moderately sized or persistent pseudoaneurysms (PSAs). Although rare, the most feared complication of UGTI is arterial thrombosis or embolism during the off-label injection of thrombin causing acute limb ischemia requiring emergent surgical intervention. Higher thrombin volume, rapidity of injection, and wide or short-neck PSAs are all thought to increase the risk of arterial thrombosis or embolism during this procedure. For patients with unfavorable PSA anatomy who are high-risk surgical candidates due to their medical comorbidities or active critical illness, balloon-assisted thrombin injection (BATI) has been suggested as a means to potentially reduce the risk of thrombosis or distal embolization associated with UGTI. This minimally invasive technique also decreases the risk of groin wound dehiscence or infection associated with open repair, especially in patients who are morbidly obese or have had prior groin surgery. We report a patient with a complex femoral artery PSA after endovascular intervention who was successfully treated with BATI and describe the procedure in detail.


Assuntos
Falso Aneurisma/terapia , Oclusão com Balão , Artéria Femoral/lesões , Doença Iatrogênica , Trombina/administração & dosagem , Ultrassonografia de Intervenção , Lesões do Sistema Vascular/terapia , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/etiologia , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Injeções Intra-Arteriais , Pessoa de Meia-Idade , Resultado do Tratamento , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia
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