Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
Toxicon ; 199: 87-93, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34126124

RESUMO

Snakebite accidents are a public health problem that affects the whole world, causing thousands of deaths and amputations each year. In Brazil, snakebite envenomations are caused mostly by snakes from the Bothrops genus. The local symptoms are characterized by pain, swelling, ecchymosis, and hemorrhages. Systemic disturbances can lead to necrosis and amputations. The present treatment consists of intravenous administration of bothropic antivenom, which is capable of reversing most of the systemic symptoms, while presenting limitations to treat the local effects, such as hemorrhage and to neutralize the snake venom serine protease (SVSP). In this context, we aimed to evaluate the activity of selective serine protease inhibitors (pepC and pepB) in combination with the bothropic antivenom in vivo. Further, we assessed their possible synergistic effect in the treatment of coagulopathy and hemorrhage induced by Bothrops jararaca venom. For this, we evaluated the in vivo activity in mouse models of local hemorrhage and a series of in vitro hemostasis assays. Our results showed that pepC and pepB, when combinated with the antivenom, increase its protective activity in vivo and decrease the hemostatic disturbances in vitro with high selectivity, possibly by inhibiting botropic proteases. These data suggest that the addition of serine protease inhibitor to the antivenom can improve its overall potential.


Assuntos
Bothrops , Venenos de Crotalídeos , Animais , Antivenenos/farmacologia , Antivenenos/uso terapêutico , Brasil , Venenos de Crotalídeos/toxicidade , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Camundongos , Inibidores de Serino Proteinase/farmacologia , Inibidores de Serino Proteinase/uso terapêutico
2.
J Am Heart Assoc ; 10(5): e018243, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33624506

RESUMO

Background White blood cell count, which is inexpensive and widely available in clinical practice, has been proposed to provide prognostic information in coronary artery disease (CAD). Elevated levels of white blood cell subtypes may play different roles in atherothrombosis and predict cardiovascular outcomes. Methods and Results The association between white blood cell counts and mortality was evaluated in 823 subjects with angiographically demonstrated and clinically stable CAD in an observational-longitudinal study. The correlation among white blood cell counts and factor II plasma coagulant activity was analyzed in 750 subjects (554 CAD and 196 CAD-free) not taking anticoagulant drugs. Subjects with overt leukocytosis or leukopenia were excluded. In the longitudinal study after a median follow-up of 61 months, 160 (19.4%) subjects died, 107 (13.0%) of whom from cardiovascular causes. High levels of neutrophils, monocytes, eosinophils, and basophils were associated with an increased mortality rate. In multiadjusted Cox regression models, only neutrophils and basophils remained predictors of total and cardiovascular mortality. The associations remained significant after adjustment for traditional cardiovascular risk factors and by including D-dimer and the chemokine CXCL12 in the regression models. Neutrophils and basophils were also significant predictors of factor II plasma coagulant activity variability after adjustment for blood cell counts, age, sex, inflammatory markers, CAD diagnosis, and prothrombin G20210A polymorphism. Factor II plasma coagulant activity was similarly increased in subjects with high neutrophil and basophil counts and in carriers of the prothrombin 20210A allele. Conclusions Both high neutrophil and basophil blood counts may predict mortality in patients with clinically stable CAD and are associated with enhanced factor II plasma coagulant activity, thereby suggesting underlying prothrombotic mechanisms.


Assuntos
Basófilos/patologia , Doença da Artéria Coronariana/sangue , Isquemia Miocárdica/sangue , Neutrófilos/patologia , Protrombina/metabolismo , Medição de Risco/métodos , Biomarcadores/sangue , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/mortalidade , Feminino , Seguimentos , Humanos , Itália/epidemiologia , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/mortalidade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências
3.
Mar Drugs ; 19(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540717

RESUMO

For tissue engineering applications, biodegradable scaffolds containing high molecular weights (MW) of collagen and sodium alginate have been developed and characterized. However, the properties of low MW collagen-based scaffolds have not been studied in previous research. This work examined the distinctive properties of low MW collagen-based scaffolds with alginate unmodified and modified by subcritical water. Besides, we developed a facile method to cross-link water-soluble scaffolds using glutaraldehyde in an aqueous ethanol solution. The prepared cross-linked scaffolds showed good structural properties with high porosity (~93%) and high cross-linking degree (50-60%). Compared with collagen (6000 Da)-based scaffolds, collagen (25,000 Da)-based scaffolds exhibited higher stability against collagenase degradation and lower weight loss in phosphate buffer pH 7.4. Collagen (25,000 Da)-based scaffolds with modified alginate tended to improve antioxidant capacity compared with scaffolds containing unmodified alginate. Interestingly, in vitro coagulant activity assay demonstrated that collagen (25,000 Da)-based scaffolds with modified alginate (C25-A63 and C25-A21) significantly reduced the clotting time of human plasma compared with scaffolds consisting of unmodified alginate. Although some further investigations need to be done, collagen (25,000 Da)-based scaffolds with modified alginate should be considered as a potential candidate for tissue engineering applications.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Colágeno/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Alginatos/farmacologia , Materiais Biocompatíveis/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Sanguínea/fisiologia , Fenômenos Químicos/efeitos dos fármacos , Colágeno/farmacologia , Humanos , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Resistência à Tração/efeitos dos fármacos , Resistência à Tração/fisiologia
4.
Toxicon, v. 199, p. 87-93, ago. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3860

RESUMO

Snakebite accidents are a public health problem that affects the whole world, causing thousands of deaths and amputations each year. In Brazil, snakebite envenomations are caused mostly by snakes from the Bothrops genus. The local symptoms are characterized by pain, swelling, ecchymosis, and hemorrhages. Systemic disturbances can lead to necrosis and amputations. The present treatment consists of intravenous administration of bothropic antivenom, which is capable of reversing most of the systemic symptoms, while presenting limitations to treat the local effects, such as hemorrhage and to neutralize the snake venom serine protease (SVSP). In this context, we aimed to evaluate the activity of selective serine protease inhibitors (pepC and pepB) in combination with the bothropic antivenom in vivo. Further, we assessed their possible synergistic effect in the treatment of coagulopathy and hemorrhage induced by Bothrops jararaca venom. For this, we evaluated the in vivo activity in mouse models of local hemorrhage and a series of in vitro hemostasis assays. Our results showed that pepC and pepB, when combinated with the antivenom, increase its protective activity in vivo and decrease the hemostatic disturbances in vitro with high selectivity, possibly by inhibiting botropic proteases. These data suggest that the addition of serine protease inhibitor to the antivenom can improve its overall potential.

5.
Int J Mol Sci ; 21(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371421

RESUMO

(1) Background: survivors of allogeneic hematopoietic cell transplantation (alloHCT) suffer from morbidity and mortality due to cardiovascular events. We hypothesized that vascular injury and pro-coagulant activity are evident in alloHCT survivors without existing alloHCT complications or relapse. (2) Methods: we enrolled consecutive adult alloHCT survivors without established cardiovascular disease and control individuals matched for traditional cardiovascular risk factors (January-December 2019). Circulating microvesicles (MVs) of different cellular origins (platelet, erythrocyte, and endothelial) were measured by a standardized flow cytometry protocol as novel markers of vascular injury and pro-coagulant activity. (3) Results: we recruited 45 survivors after a median of 2.3 (range 1.1-13.2) years from alloHCT, and 45 controls. The majority of patients suffered from acute (44%) and/or chronic (66%) graft-versus-host disease (GVHD). Although the two groups were matched for traditional cardiovascular risk factors, alloHCT survivors showed significantly increased platelet and erythrocyte MVs compared to controls. Within alloHCT survivors, erythrocyte MVs were significantly increased in patients with a previous history of thrombotic microangiopathy. Interestingly, endothelial MVs were significantly increased only in alloHCT recipients of a myeloablative conditioning. Furthermore, MVs of different origins showed a positive association with each other. (4) Conclusions: endothelial dysfunction and increased thrombotic risk are evident in alloHCT recipients long after alloHCT, independently of traditional cardiovascular risk factors. An apparent synergism of these pathophysiological processes may be strongly involved in the subsequent establishment of cardiovascular disease.


Assuntos
Fatores de Coagulação Sanguínea , Doenças Cardiovasculares/diagnóstico , Micropartículas Derivadas de Células/patologia , Endotélio Vascular/lesões , Doença Enxerto-Hospedeiro/etiologia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Adulto , Sobreviventes de Câncer/estatística & dados numéricos , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Feminino , Doença Enxerto-Hospedeiro/patologia , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo , Adulto Jovem
6.
Biochimie ; 174: 171-188, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32302625

RESUMO

We investigated the histology of Duvernoy's venom gland and the biochemical and biological activities of Leptodeira annulata snake venom. The venom gland had a lobular organization, with secretory tubules formed by serous epithelial cells surrounding each lobular duct. The latter drained into a common lobular duct and subsequently into a central cistern. In contrast, the supralabial gland was mucous in nature. SDS-PAGE revealed a profile of venom components that differed from pitviper (Bothrops spp.) venoms. RP-HPLC also revealed greater complexity of this venom compared to Bothrops venoms. The venom had no esterase, l-amino acid oxidase or thrombin-like activity, but was proteolytic towards elastin-Congo red, fibrin, fibrinogen, gelatin and hide powder azure. The venom showed strong α-fibrinogenase and fibrinolytic activities and reduced the rate and extent of plasma recalcification. The proteolytic activity was inhibited by EDTA and 1,10-phenanthroline (metalloproteinase inhibitors) but not by AEBSF and PMSF (serine proteinase inhibitors). The venom had phospholipase A2 (PLA2) activity that was inhibited by varespladib. The venom cross-reacted with antivenoms to lancehead (Bothrops spp.), coralsnake (Micrurus spp.) and rattlesnake (Crotalus durissus terrificus) venoms. The venom did not aggregate rat platelets or inhibit collagen-induced aggregation, but partially inhibited thrombin-induced aggregation. The venom was hemorrhagic (inhibited by EDTA) and increased the vascular permeability (inhibited by varespladib) in rat dorsal skin. In gastrocnemius muscle, the venom caused myonecrosis and increased serum creatine kinase concentrations. In conclusion, L. annulata venom has various enzymatic and biological activities, with the local effects being mediated primarily by metalloproteinases and PLA2.


Assuntos
Colubridae , Venenos de Serpentes , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Wistar , Venenos de Serpentes/química , Venenos de Serpentes/enzimologia
7.
Biochem Biophys Res Commun ; 526(3): 633-640, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32248973

RESUMO

Factor VIII (FVIII) functions as a cofactor within the intrinsic pathway of blood coagulation in process of FX activation by FIXa, for which deficiency results in the bleeding disorder hemophilia A. The gene of FVIII contains 26 exons that code for a 19 amino acid signal peptide and a 2332 amino acid polypeptide with a domain structure designated A1-A2-B-A3-C1-C2, of which the A domains are homologous with each other, as are the C domains. It has been well-documented that both the domains are the necessary elements for FVIII activities. The B domain is highly glycosylated and has a variable sequence, even among FVIIIs from different species. The B domain plays versatile roles in FVIII lifespan except for coagulation activity, but the functional characteristics of its specific regions remain still obscure. A series of recombinant FVIIIs (rFVIIIs) with B domain truncated were constructed and transiently expressed in hepatocyte cells. Media and cell lysates were collected after 72 h for the analyses of FVIII biosynthesis, secretion, activity and stability in ex vivo plasma relative to the full length wild-type FVIII. Unexpectedly, various regions in B domain exhibited different contribution to these functionalities. The discovery might facilitate the bioengineered rFVIIIs and gene therapeutics.


Assuntos
Fator VIII/metabolismo , Hepatócitos/metabolismo , Linhagem Celular , Éxons , Fator VIII/química , Fator VIII/genética , Humanos , Mutação , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
8.
Carbohydr Res ; 485: 107813, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541938

RESUMO

A novel polysaccharide in Malus halliana Koehne, named MHP-W, was isolated and purified by DEAE-52 cellulose and Sephadex G-100 columns. Structural features were identified by high performance size-exclusion chromatography (HPSEC), fourier transform infrared (FT-IR) spectrometer, gas chromatography (GC) and (1D & 2D) NMR Spectroscopy. Structural characterization showed that the molecular weight of MHP-W was 353 kDa composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 2.59: 0.15: 0.23: 0.25: 9.70. The existence of ß-glycosidic bond between the sugar units was confirmed by FT-IR and NMR spectroscopy. The effects of MHP-W on active part thrombin time (APTT), protothrombin time (PT), thrombin time (TT), and fibrinogen (FIB) were screened by a cell-based coagulation activity model. MHP-W could significantly shorten TT (p < 0.001) and increase FIB (p < 0.05) as compared with the control group. The results showed that MHP-W promoted bloodclotting through endogenous and exogenous coagulation pathways as well as increasing fibrinogen content, which indicated that MHP-W had procoagulant activities in vitro.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Malus/química , Polissacarídeos/farmacologia , Animais , Sequência de Carboidratos , Masculino , Peso Molecular , Monossacarídeos/análise , Polissacarídeos/química , Coelhos
9.
J Ethnopharmacol ; 242: 112046, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31279070

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In Colombia, the only authorized treatment to cure snakebite envenomation is with the use of antivenom. The antivenom neutralizes the systemic effects properly, but is not very effective at neutralizing local effects, thus several cases have lead to complications. On the other hand, rural communities turn to the use of plants that are easily accessible and available for basic health care. One of these plants is named Piper auritum (PA), which is traditionally highlighted in some indigenous communities of Antioquia and Chocó. AIM OF THE STUDY: The main objective of this work was to characterize the venom's toxicity by determining the Minimum Edema Dose (MED), the Minimum Coagulant Dose-Plasma (MCD-P), the Minimum Hemorrhagic Dose (MHD) and to determine the neutralizing power of the Total Ethanolic Extract (TEE) from leaves of PA on the localized and systemic effects caused by the Bothrops rhombeatus venom. MATERIALS AND METHODS: To begin, the minimum dose that causes edema-forming, coagulant and hemorrhagic activities was determined. The protocols investigated include coagulant and edematic activities caused by the venom of Bothrops rhombeatus which were neutralized by the TEE of PA. RESULTS: The MCD-P was found to be 0.206 ±â€¯0.026 µg, the MED is the same at 0.768 ±â€¯0.065 µg, and the MHD is 3.553 ±â€¯0.292 µg, which are different from the reports for Bothrops asper and Bothrops ayerbei. Next, a phytochemical screening was done to the TEE where mainly triterpenes, steroids, coumarins, saponins, and lignans were identified. Also present were 43,733 ±â€¯2106 mg AG/g ES of phenols, which are secondary metabolites that are probably responsible for the neutralization of coagulant and edematic activities at rates of 2363.870 µL and 1787.708 µL of extract/mg of venom, respectively. As a comparative parameter, the National Institute Health's (NHI) effective dose of the antivenom was used as a comparative parameter. In addition, we determined the toxicity of the TEE of PA on to Artemia salina, being moderately toxic at 6 and 24 h, while the essential oil of PA at the same observation hours is in the extremely toxic range. CONCLUSIONS: The results reflect that the extract of P. auritum has an anti-inflammatory effect similar to that of the NIH serum. It could be used as a complement of NIH antivenom, using them together so it contributes to effectively reduce inflammation and the socio-economic impact generated by the permanence of a patient victim of snakebite in health centers. CLASSIFICATIONS: Immunological products and vaccines.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticoagulantes/uso terapêutico , Antivenenos/uso terapêutico , Venenos de Crotalídeos/toxicidade , Piper , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anticoagulantes/química , Anticoagulantes/farmacologia , Antivenenos/química , Antivenenos/farmacologia , Artemia/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Bothrops , Edema/tratamento farmacológico , Etanol/química , Hemorragia/tratamento farmacológico , Camundongos Endogâmicos ICR , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Mordeduras de Serpentes/tratamento farmacológico , Solventes/química
10.
Vet Immunol Immunopathol ; 211: 49-57, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084894

RESUMO

Histophilus somni is a Gram negative coccobacillus that causes respiratory, reproductive and central nervous system disease in cattle. The hallmark of H. somni infection is diffuse vasculitis and intravascular thrombosis that can lead to an acute central nervous system disease known as thrombotic meningoencephalitis (TME). Because neutrophils are major players in the pathophysiology of septic meningitis, we sought to determine their role in H. somni-induced fibrin clot formation in vitro. Bovine brain endothelial cells (TBBE cells) were exposed to H. somni cells at a 1:25 ratio, respectively. Conditioned media (CM) were collected after a 6 h incubation at 37 °C with 5% CO2, and then incubated with bovine peripheral blood polymorphonuclear neutrophils (PMNs). Following incubation, fibrin clot formation and tissue factor activity were assessed by a re-calcified plasma clotting assay. We found greater tissue factor activity in cell lysates and CM from H. somni-stimulated TBBE cells than unstimulated control TBBE cells. In addition, PMNs exposed to CM or extracellular vesicles from H. somni-stimulated TBBE cells expressed von Willenbrand factor, exhibited increased fibrin clot formation, and displayed greater tissue factor activity than PMNs exposed to CM or extracellular vesicles from unstimulated control TBBE cells. These results suggest that bovine PMNs might acquire extracellular vesicles from endothelial cells that leads to thrombus formation in bovine brain microvasculature and contribute to the process that characterizes TME.


Assuntos
Encéfalo/microbiologia , Doenças dos Bovinos/microbiologia , Células Endoteliais/microbiologia , Vesículas Extracelulares/microbiologia , Neutrófilos/imunologia , Infecções por Pasteurellaceae/veterinária , Pasteurellaceae , Animais , Encéfalo/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Meios de Cultivo Condicionados , Células Endoteliais/imunologia , Vesículas Extracelulares/imunologia , Interações Hospedeiro-Patógeno/imunologia , Neutrófilos/fisiologia , Pasteurellaceae/imunologia , Infecções por Pasteurellaceae/imunologia , Trombose/imunologia , Trombose/microbiologia , Trombose/veterinária
11.
J Food Sci Technol ; 56(2): 589-598, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30906016

RESUMO

Iranian Ultrafiltered White cheese was produced by using different blends of coagulants (100:0, 75:25, 50:50, 25:75 and 0:100; Rhizomucor miehei and camel chymosin, respectively) and ripened for 90 days. The effect of different combinations of these coagulants on chemical composition, proteolysis and residual coagulant activity of the cheeses were studied. The results showed that pH, fat-in-dry matter, salt-in-dry matter and protein contents of the cheeses were significantly influenced by type and concentration of the coagulants. The difference between proteolytic activities of the two coagulants resulted in different levels of proteolysis in the cheeses. A direct relationship was determined between using higher concentrations of R. miehei and increasing the hydrolysis of αs1-casein in the cheeses, during ripening. The residual coagulant activity was influenced by the type and concentration of the coagulant as well. In conclusion, R. miehei provided a higher level of proteolysis and residual coagulant activity compared with camel chymosin.

12.
Toxicon ; 140: 32-37, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29051104

RESUMO

Arboreal pit vipers of the Trimeresurus complex group are medically important species in Indonesia (west of Wallace's line), but there is no specific antivenom produced in the country for treating related envenomation. Instead, the exiting trivalent Indonesian antivenom, Biosave® Serum Anti Bisa Ular (SABU, indicated for envenoming by Malayan pit viper, Javan spitting cobra and banded krait) is often misused to treat Trimeresus envenoming resulting in poor therapeutic outcome. Here, we investigated the cross-reactivity and neutralization capability of Thai Green Pit Viper Antivenom (GPVAV) against the venoms of four Indonesian Trimeresurus species. Consistently, the venoms of Trimeresurus (Trimeresurus) insularis, Trimeresurus (Trimeresurus) purpureomaculatus, Trimeresurus (Parias) hageni and Trimeresurus (Craspedocephalus) puniceus of Indonesia showed stronger immunoreactivity on ELISA to GPVAV than to Biosave®. The findings correlated with in vivo neutralization results, whereby GPVAV was far more effective than Biosave® in cross-neutralizing the lethality of the venoms by a potency of at least 13 to 80 times higher. The efficacy of GPVAV is partly attributable to its cross-neutralization of the procoagulant effect of the venoms, thereby mitigating the progression of venom-induced consumptive coagulopathy. The paraspecific effectiveness of GPVAV against Trimeresurus species envenoming in Indonesia await further clinical investigation.


Assuntos
Antivenenos/imunologia , Venenos de Crotalídeos/imunologia , Trimeresurus , Animais , Antivenenos/farmacologia , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática , Indonésia , Camundongos Endogâmicos ICR , Testes de Neutralização
13.
Foods ; 6(8)2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-28783066

RESUMO

In this study, the potential use of Moringa oleifera as a clotting agent of different types of milk (whole, skim, and soy milk) was investigated. M. oleifera seed extract showed high milk-clotting activity followed by flower extract. Specific clotting activity of seed extract was 200 times higher than that of flower extract. Seed extract is composed by four main protein bands (43.6, 32.2, 19.4, and 16.3 kDa). Caseinolytic activity assessed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and tyrosine quantification, showed a high extent of casein degradation using M. oleifera seed extract. Milk soy cheese was soft and creamy, while skim milk cheese was hard and crumbly. According to these results, it is concluded that seed extract of M. oleifera generates suitable milk clotting activity for cheesemaking. To our knowledge, this study is the first to report comparative data of M. oleifera milk clotting activity between different types of soy milk.

14.
Bioorg Med Chem Lett ; 27(18): 4506-4511, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28844387

RESUMO

Ten new cinnamic acid derivatives containing a 2-aminothiazole substructure were designed and synthesized. This series of compounds exhibited good thermostabilities as demonstrated by thermogravimetric analysis. In coagulation assays (prothrombin time, activated partial thromboplastin time and thrombin time) in vitro, most compounds demonstrated excellent activities to promote blood coagulation. Among the studied series, compounds N1, N4, N5 and W5 exhibited a significant coagulation activity. Further studies indicated that compound N5 (IC50=1.87µmol/L) displayed the most suitable efficacy of promoting platelet aggregation than the clinically used haemostatic drug etamsylate (IC50=46.22µmol/L). Furthermore, the relationship between the functional groups of the compounds and the corresponding blood coagulant activity was explored in this study.


Assuntos
Amidas/farmacologia , Cinamatos/farmacologia , Hemostáticos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Tiazóis/farmacologia , Amidas/síntese química , Amidas/química , Coagulação Sanguínea/efeitos dos fármacos , Cinamatos/síntese química , Cinamatos/química , Relação Dose-Resposta a Droga , Hemostáticos/síntese química , Hemostáticos/química , Humanos , Estrutura Molecular , Tempo de Tromboplastina Parcial , Inibidores da Agregação Plaquetária/síntese química , Inibidores da Agregação Plaquetária/química , Tempo de Protrombina , Relação Estrutura-Atividade , Tiazóis/química , Tempo de Trombina
15.
Mar Drugs ; 15(8)2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28777290

RESUMO

Sulphated polysaccharides with anti-thrombotic and anti-coagulant activities have been found in various marine biota. In this study, a previously characterised anti-thrombotic and anti-coagulant extract from blacklip abalone was fractionated by anion exchange chromatography (AEC), pooled (on a sulphated polysaccharide basis) and administered to Wistar rats via oral gavage (N = 8) for assessment as an oral therapeutic. To ensure that the preparation had anti-coagulant activity prior to oral administration, it was assessed in rat blood by thromboelastography (TEG) significantly increasing reaction (R) time (or time until clot formation). Following in vitro confirmation of anti-coagulant activity, 40 mg of the preparation was orally administered to rats with blood samples collected at 2, 4, and 6 h post-gavage. Assessment of all blood samples by TEG showed some prolongation of R time from 355 to 380 s after 4 h. Dosing of the post-gavage blood samples with the abalone preparation to confirm anti-thrombotic activity in vitro revealed residual anti-coagulant activity, further suggesting that oral administration did increase anti-coagulant potential in the collected blood but that bioavailability was low. Assessment of tissues and haematological parameters showed no obvious harmful effects of the abalone preparation in animals. In summary, even though oral administration of fractionated and pooled blacklip abalone extract to rats delayed clotting after 4 h, bioavailability of the preparation appeared to be low and may be more appropriate for intravenous administration as an anti-thrombotic or anti-coagulant therapeutic.


Assuntos
Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/farmacologia , Gastrópodes/química , Alimentos Marinhos , Animais , Anticoagulantes/química , Testes de Coagulação Sanguínea , Fibrinolíticos/química , Técnicas In Vitro , Polissacarídeos , Ratos , Ratos Wistar
16.
Mol Immunol ; 87: 171-179, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28494352

RESUMO

Fulminant hepatitis (FH) is characterized by rapid liver failure and high mortality. The pathogenesis of viral FH includes virus-induced immune activation, inflammation, and subsequent hepatic apoptosis and necrosis. However, the mechanisms that underlie FH progression are unclear. IL-33 is a member of the IL-1-related cytokines, considered to be an "alarmin" that participates in various diseases, but its precise role in the coagulation of FH is not very clear. In our study, we found that IL-33 is significantly elevated in mice infected with murine hepatitis virus strain 3 (MHV-3). This is accompanied by an increase in pro-coagulant fibrinogen-like protein 2 (FGL2) in the liver. Previous studies have suggested that an increase in FGL2 is diagnostic of FH and liver necrosis, and animals with no FGL2 had better survivorship during FH. Our studies showed that IL-33 administration in a MHV-3 infection promoted survival during FH, with a significant reduction in FGL2 expression and liver inflammation. In vitro IL-33 treatment abrogated MHV-3 and IFN-γ induced FGL2 expression in RAW264.7 and THP-1 cells, respectively. In conclusion, our research suggests that IL-33 protects against viral fulminant hepatitis in mice by antagonizing expression of the pro-coagulant protein FGL2.


Assuntos
Coagulação Sanguínea/fisiologia , Fibrinogênio/metabolismo , Hepatite Viral Animal/metabolismo , Interleucina-33/metabolismo , Vírus da Hepatite Murina/metabolismo , Animais , Apoptose/fisiologia , Feminino , Inflamação/metabolismo , Inflamação/virologia , Interferon gama/metabolismo , Interleucina-1/metabolismo , Fígado/metabolismo , Fígado/virologia , Camundongos , Camundongos Endogâmicos BALB C
17.
BMC Complement Altern Med ; 17(1): 93, 2017 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-28166786

RESUMO

BACKGROUND: In the Chinese traditional medicine, plant of Agastache rugosa (Fisch. & C.A. Mey.) Kuntze (A. rugosa) has been used to treat nausea, vomiting and dispel damp. However, currently, few reports about the chemical constituents, especially the non-volatile components of A. rugosa are available. METHODS: Through separation with various column chromatographies to elucidate the chemical constituents of A. rugosa, the biological activities of the major constituents were investigated. The extracts and main constituents of A. rugosa were evaluated for their anticoagulant effects by assaying the activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and fibrinogen (FIB) in vitro. RESULTS: Seven known compounds (namely compounds 1-7) were isolated from the aerial parts of A. rugosa. They were identified as methyl hexadecanoate (1), ß-sitosterol (2), acacetin (3), ursolic acid (4), apigenin (5), protocatechuic acid (6) and tilianin (7), respectively. Compounds 1 and 6 were isolated from the genus Agastache for the first time, and compound 4 was obtained from the plants for the first time. The results showed that the extract of A. rugosa had a significant procoagulant activity by shortening the time of PT (P < 0.001) and increasing FIB content (P < 0.001), as compared with Vitamin K1. While its major constituents acacetin and tilianin exhibited significant anticoagulant activities by prolonging the times of PT, APTT, TT and reducing FIB content (P < 0.001), as compared with blank control group. CONCLUSIONS: The total extract of A. rugosa possessed significant procoagulant activity, while its main components, acacetin and tilianin possessed significant anticoagulant activities. Further investigation should be pursued to find out the bioactivity components responsible for the procoagulant action of the plant.


Assuntos
Agastache , Anticoagulantes/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Anticoagulantes/química , Cromatografia , Fibrinogênio/efeitos dos fármacos , Humanos , Tempo de Tromboplastina Parcial , Componentes Aéreos da Planta , Extratos Vegetais/química , Coelhos
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-606081

RESUMO

Objective To observe the change of serum homocysteine (Hcy) ,plasma von willebrand factor (vWF) and whole blood tissue factor procoagulant activity (TF-PCA) within 48 h of onset in the patients with coronary heart disease (CHD).Meth-ods The relevant instrument was adopted to detect the level of serum Hcy ,plasma vWF and whole blood TF-PCA in 300 CHD pa-tients and 100 individuals undergoing the healthy physical examination ,and then the statistical analysis was performed.Three hundreds cases of CHD were divided into the stable angina group (SAP group ,n= 96) ,unstable angina group (UAP group ,n=100) and acute myocardial infarction group (AMI group ,n=104).Results The Hcy ,vWF and TF-PCA levels in the CHD patients were higher than those in the control group ,the difference was statistically significant (PUAP group> SAP group ,the difference was statistically significant (P<0.05).The vWF and TF-PCA levels in the AMI group and UAP group were higher than those in the SAP group with statistical difference (P<0.05).The Hcy level in SAP ,UAP and AMI patients complicated with diabetes and hypertension was significantly increased compared with the patients without complicating di-abetes and hypertension ,the difference was statistically significant (P<0.05).The vWF and TF-PCA levels had statistical differ-ence between the UAP group and AMI group(P<0.05).Conclusion Routinely detecting the levels of Hcy ,vWF and TF-PCA has an important clinical value for the diagnosis and curative effect observation in the patients with CHD.

19.
Data Brief ; 8: 618-27, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27437434

RESUMO

This article contains data on the variation in several physiological parameters of red blood cells (RBCs) donated by eligible glucose-6-phosphate dehydrogenase (G6PD) deficient donors during storage in standard blood bank conditions compared to control, G6PD sufficient (G6PD(+)) cells. Intracellular reactive oxygen species (ROS) generation, cell fragility and membrane exovesiculation were measured in RBCs throughout the storage period, with or without stimulation by oxidants, supplementation of N-acetylcysteine and energy depletion, following incubation of stored cells for 24 h at 37 °C. Apart from cell characteristics, the total or uric acid-dependent antioxidant capacity of the supernatant in addition to extracellular potassium concentration was determined in RBC units. Finally, procoagulant activity and protein carbonylation levels were measured in the microparticles population. Further information can be found in "Glucose 6-phosphate dehydrogenase deficient subjects may be better "storers" than donors of red blood cells" [1].

20.
Appl Biochem Biotechnol ; 180(7): 1361-1371, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27351986

RESUMO

Moringa oleifera seeds contain a water-soluble lectin [water-soluble M. oleifera lectin (WSMoL)] that has shown coagulant activity. Magnesium ions are able to interfere with the ability of this lectin to bind carbohydrates. In this study, we performed structural characterization of WSMoL and analyzed its effect on the electrical resistance of a kaolin clay suspension in both presence and absence of monosaccharides (N-acetylglucosamine, glucose, or fructose) and magnesium ions. The coagulant activity of WSMoL was monitored by measuring optical density and electrical resistance over a period of 60 min. Native WSMoL had a molecular mass of 60 kDa and exhibited anionic nature (pI 5.5). In sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), it appeared as three polypeptide bands of 30, 20, and 10 kDa. WSMoL reduced the optical density and electrical resistance of the kaolin suspension, which suggests that suspended particles are destabilized and that this is followed by formation of complexes. The coagulant activity of lectin decreased in the presence of Mg2+ ions and carbohydrates at concentrations that also inhibited hemagglutinating activity. This was most likely due to conformational changes in lectin structure. Our findings suggest that the coagulant activity of WSMoL is enhanced by lowering of electrical resistance of the medium and is impaired by lectin-carbohydrate and lectin-Mg2+ interactions.


Assuntos
Impedância Elétrica , Lectinas/farmacologia , Magnésio/farmacologia , Monossacarídeos/farmacologia , Moringa oleifera/química , Água/química , Animais , Cromatografia em Gel , Coagulantes/farmacologia , Floculação/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Íons , Coelhos , Solubilidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...