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1.
Acta sci., Biol. sci ; 34(2): 141-148, Apr.-June 2012. ilus, tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-860030

RESUMO

O Brasil abriga uma das maiores biodiversidades marinhas do mundo, favorecendo a descoberta de fontes alternativas de compostos farmacológicos. Desta forma, objetivou-se avaliar o potencial anticoagulante de glicosaminoglicanos (GAGs) isolados das peles da palombeta (Chloroscombrus chrysurus) e guaiúba (Ocyurus chrysurus). Os GAGs foram extraídos com papaína bruta em tampão acetato de sódio 0,1 M (pH 5,0) contendo cisteína 5 mM e EDTA 5 mM, seguido por cromatografia de troca iônica do extrato total em coluna de DEAE-celulose. As frações obtidas foram analisadas quanto à composição química (proteínas contaminantes e carboidratos totais) e os GAGs identificados por eletroforese em gel de agarose a 0,5%. Os ensaios de atividade anticoagulante foram realizados por meio do tempo de tromboplastina parcial ativada (TTPA) usando plasma humano normal e heparina-padrão (193,00 UI mg-1). O procedimento de obtenção e fracionamento dos GAGs mostrou-se eficiente, indicando semelhantes perfis cromatográficos entre as espécies avaliadas e, revelando para C. chrysurus, bandas com mobilidades semelhantes ao dermatam sulfato e com atividade de apenas 3,30 UI mg-1.


A great number of pharmacological compounds is found in the Brazilian marine diversity. This study evaluated the anticoagulant potential of glycosaminoglycans (GAGs) isolated from the skin of 'palombeta' Chloroscombrus chrysurus and 'guaiúba' Ocyurus chrysurus. GAGs were extracted with crude papain in 0.1 M sodium acetate buffer (pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by ion exchange chromatography on DEAE-cellulose column. The chemical composition (contaminant proteins and total carbohydrates) and the analysis by 0.5% agarose gel electrophoresis of fractions were also determined. Anticoagulant assays were performed by activated partial thromboplastin time (APTT) using normal human plasma and standard heparin (193.00 IU mg-1). The obtaining and fractionation procedures of GAGs were effective and similar chromatographic profiles were verified between the species. A similar mobility to dermatan sulfate was revealed for C. chrysurus. This GAG also showed a low activity of 3.30 IU mg-1.


Assuntos
Animais , Farmacologia , Coagulação Sanguínea , Ambiente Marinho , Ativador de Plasminogênio Tecidual , Biodiversidade , Glicosaminoglicanos
2.
Acta sci., Biol. sci ; 33(2): 133-140, Apr. - Jun. 2011. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-875391

RESUMO

The reportedly low standard quality of heparin (HEP) for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs) from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs) from Caulerpa cupressoides (Chlorophyceae) with papain in 100 mM sodium acetate buffer (pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose), and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT) using normal human plasma and compare it to standard HEP (193 IU mg-1). The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III) eluted with 0.50, 0.75 and 1.00 M of NaCl, respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.


O baixo padrão de qualidade outrora declarado da heparina (HEP) para o uso em cirurgias cardíacas tem levado preocupação nos mercados nacional e internacional. Os polissacarídeos sulfatados (PSs) de algas marinhas têm sido considerados como promissores substitutos para HEP. Objetivou-se a extrair sequencialmente PSs totais (PSTs) da clorofícea Caulerpa cupressoides com papaína em tampão acetato de sódio 100 mM (pH 5,0) contendo cisteína 5 mM e EDTA 5 mM, fracionar por cromatografia de troca iônica (DEAE-celulose) e avaliar o potencial anticoagulante das frações de PS por meio do tempo de tromboplastina parcial ativada (TTPA), utilizando plasma humano normal e comparando-se à HEP padrão (193 IU mg-1). As frações obtidas foram caracterizadas quimicamente em composição química e por eletroforese em gel de agarose. O rendimento de PSTs foi 4,61% e os perfis cromatográficos, em DEAE-celulose, indicaram a separação de três frações de PS (F I; F II e F III) eluídas nas concentrações 0,50; 0,75 e 1,00 M de NaCl, respectivamente, revelando, por eletroforese, diferenças em termos de densidade de cargas e grau de resolução. Os PSs foram capazes de modificar o TTPA somente nas frações eluídas com 0,75 M de NaCl, cujas atividades foram 23,37 e 25,76 IU mg-1, respectivamente, quando a densidade de cargas foi pré-requisito para atividade. Portanto, C. cupressoides é uma fonte de PSs com baixos potenciais anticoagulantes comparados à HEP.


Assuntos
Coagulação Sanguínea , Clorófitas
3.
Acta sci., Biol. sci ; 33(2): 133-140, Apr. - Jun. 2011.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1460673

RESUMO

The reportedly low standard quality of heparin (HEP) for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs) from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs) from Caulerpa cupressoides (Chlorophyceae) with papain in 100 mM sodium acetate buffer (pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose), and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT) using normal human plasma and compare it to standard HEP (193 IU mg-1). The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III) eluted with 0.50, 0.75 and 1.00 M of NaCl, respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.


The reportedly low standard quality of heparin (HEP) for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs) from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs) from Caulerpa cupressoides (Chlorophyceae) with papain in 100 mM sodium acetate buffer (pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose), and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT) using normal human plasma and compare it to standard HEP (193 IU mg-1). The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III) eluted with 0.50, 0.75 and 1.00 M of NaCl, respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.

4.
Acta sci., Biol. sci ; 32(2): 113-120, abr.-jun.2010. graf, ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1460655

RESUMO

A incidência de doenças cardiovasculares e os efeitos adversos da heparinoterapiatêm motivado a busca por novos agentes terapêuticos e os polissacarídeos sulfatados (PS) de algasmarinhas têm sido reportados como fontes alternativas para tal. Objetivou-se avaliar o potencialanticoagulante dos PS totais (PST) isolados e fracionados das clorofíceas Caulerpa racemosa eCaulerpa cupressoides. Inicialmente, os PST foram extraídos com papaína em tampão acetato desódio 0,1 M (pH 5,0) contendo cisteína 5 mM e EDTA 5 mM, seguidos de fracionamento emcoluna de troca iônica de DEAE-celulose com gradiente de NaCl. As frações obtidas foramanalisadas por eletroforese em gel de agarose a 0,5% e a atividade anticoagulante, mensurada pelotempo de tromboplastina parcial ativada (TTPA), usando-se plasma humano normal ecomparada a uma curva-padrão de heparina (193 UI mg-1). Verificaram-se semelhantes perfiscromatográficos entre os PS de ambas as espécies, porém com padrões de mobilidades distintasquando as frações foram comparadas por eletroforese. Os PS modificaram o TTPA, cujasatividades anticoagulantes foram de apenas 21,23 e 24,36 UI mg-1, quando eluídos com 0,75 M desal para C. racemosa e C. cupressoides, respectivamente. Portanto, PS anticoagulantes isolados dasclorofíceas C. racemosa e C. cupressoides resultaram em efeitos anticoagulantes inferiores aos daheparina. Estudos comparativos dessas moléculas também são sugeridos como ferramentasauxiliares na identificação de algas do mesmo gênero.


The incidence of cardiovascular diseases and adverse effects from heparintherapy have led to asearch for new therapeutic agents, and the sulfated polysaccharides (SP) of seaweeds have beenreported as alternative sources. The aim of this work was to evaluate the anticoagulant potentialof total SP (TSP) isolated and fractionated from Caulerpa racemosa and Caulerpa cupressoides(Chlorophyceaes). Initially, the TSP were extracted with papain in 0.1 M sodium acetate buffer(pH 5.0) containing 5 mM cysteine and 5 mM EDTA, followed by fractionation on ionexchange DEAE-cellulose column with NaCl gradient. The obtained fractions were analyzed by0.5% agarose gel electrophoresis and the anticoagulant activity measured by the activated partialthromboplastin time (APTT) using normal human plasma, and compared to a standard heparincurve (193 IU mg-1). Similar chromatographic profiles of SP were shown on both species, butwith distinct mobility patterns, when the SP fractions were compared by electrophoresis. SPeluted with 0.75 M of NaCl modified the APTT, whose anticoagulant activities were only 21.23and 24.36 IU mg-1 for C. racemosa and C. cupressoides, respectively. Therefore, anticoagulant SPisolated from chlorophyceaes showed effects inferior to heparin, and comparative studies of thesemolecules are also suggested as auxiliary tools in the identification of algae of the same genus.


Assuntos
Alga Marinha , Caulerpa , Clorófitas , Coagulação Sanguínea , Polissacarídeos
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