Navegando por Palavras-chave "Anticoagulant"
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- ItemAcesso aberto (Open Access)Expression and functional characterization of boophilin, a thrombin inhibitor from Rhipicephalus (Boophilus) microplus midgut(Elsevier B.V., 2012-07-06) Soares, Tatiane Sanches [UNIFESP]; Watanabe, Renata Midori Okuta [UNIFESP]; Tanaka-Azevedo, Anita Mitico; Torquato, Ricardo Jose Soares [UNIFESP]; Lu, Stephen [UNIFESP]; Figueiredo, Ana Carvalho; Pereira, Pedro Jose Barbosa; Tanaka, Aparecida Sadae [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Inst Butantan; Univ PortoRhipicephalus (Boophilus)microplus is an ectoparasite responsible for an important decrease in meat, milk and leather production, caused both by cattle blood loss and by the transmission of anaplasmosis and babesiosis. R. microplus is a rich source of serine protease inhibitors, including the trypsin inhibitors BmTI-A and BmTI-6, the subtilisin inhibitor BmSI, and the recently described thrombin inhibitor, boophilin. Boophilin is a double Kunitz-type thrombin inhibitor, with the unusual ability to form a ternary complex with a second (non-thrombin) serine proteinase molecule. the large-scale expression and purification of boophilin and of its isolated N-terminal (D1) domain in Pichia pastoris, its expression profile, and the effect of RNAi-mediated gene silencing in tick egg production are reported. Full-length boophilin and D1 were expressed at 21 and 37.5 mg/L of culture, respectively. Purified boophilin inhibited trypsin (K-i 0.65 nM), neutrophil elastase (K-i 21 nM) and bovine thrombin (K-i 57 pM), while D1 inhibited trypsin and neutrophil elastase (K-i of 2.0 and 129 nM, respectively), but not thrombin. Boophilin gene silencing using RNAi resulted in 20% reduction in egg weight production, suggesting that the expression of boophilin in this life stage would be important but not vital, probably due to functional overlap with other serine proteinase inhibitors in the midgut of R. microplus. Considering our data, Boophilin could be combining with other antigen in a vaccine production for tick control. (C) 2012 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosImmobilized Cratylia mollis lectin: An affinity matrix to purify a soybean (Glycine max) seed protein with in vitro platelet antiaggregation and anticoagulant activities(Elsevier B.V., 2011-01-01) Silva, Mariana C. C. [UNIFESP]; Santana, Lucimeire A. [UNIFESP]; Silva-Lucca, Rosemeire A.; Lima, Amanda L. R.; Ferreira, Joana G. [UNIFESP]; Paiva, Patricia M. G.; Coelho, Luana C. B. B.; Oliva, Maria L. V. [UNIFESP]; Zingali, Russolina B.; Correia, Maria T. S.; Universidade Federal de Pernambuco (UFPE); Universidade Federal de São Paulo (UNIFESP); Univ Estadual Oeste Parana; Universidade Federal do Rio de Janeiro (UFRJ)Lectins, proteins which recognize selectively carbohydrates, have been used as affinity chromatography to purify glycoproteins. Cratylia mollis seed lectin (Cramoll 1,4), of mannose/glucose binding class, immobilized on Sepharose CL-4B, was used as affinity matrix. This paper describes the purification by Cramoll 1,4-Sepharose matrix, and characterization of an anti-platelet and anticoagulant soybean (Glycine max) protein, ApcSP, and its in vitro platelet antiaggregation and anticoagulant activities. SDS-PAGE of ApcSP purified under reducing condition revealed a single glycosilated band of 51 kDa. the N-terminal 10-residue sequence of ApcSP is EGQFGPMIQS, distinct to other soybean seed proteins, such as peroxidase, lectin, 2S albumin and trypsin inhibitor. Deconvolution of CD spectrum indicated 35% alpha-helix, 17% beta-strand, 22% turn and 26% unordered structure; ApcSP fluorescence spectrum showed a maximum emission around 339 nm. the hemostatic parameters revealed inhibition of collagen (p<0.001), thrombin (p<0.05) and ADP (p<0.001)-induced platelet aggregation in the presence of ApcSP (2 mu M), in relation to positive control. the soy protein prolonged the blood coagulation time (activated partial thromboplastin time, more affected, and prothrombin time). the results indicated that immobilized Cramoll 1,4 lectin has the potential to isolate soybean glycoproteins and ApcSP may be important for anti-thrombotic and anticoagulant therapy. (C) 2010 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosInfluence of the intestinal anticoagulant in the feeding performance of triatomine bugs (Hemiptera; Reduviidae)(Elsevier B.V., 2011-06-01) Paim, Rafaela M. M.; Araujo, Ricardo N.; Soares, Adriana C.; Dhom Lemos, Lucas C.; Tanaka, Aparecida S. [UNIFESP]; Gontijo, Nelder F.; Lehane, Michael J.; Pereira, Marcos H.; Universidade Federal de Minas Gerais (UFMG); Universidade Federal de São Paulo (UNIFESP); Univ LiverpoolTriatomines are haematophagous insects in all post-embryonic life stages. They are vectors of Ttypanosoma cruzi, the causative agent of Chagas disease. Their vectorial ability is influenced by their feeding performance, which varies greatly amongst species. Recent work showed that inhibition of the coagulation process in the anterior midgut (crop) environment considerably influences the blood meal size. in this work, we performed a comparative study of the level of anticoagulant activity in the saliva and crop contents of three triatomine species - Triatoma infestans, Triatoma brasiliensis and Rhodnius prolixus - and correlated this with their feeding performance on live hosts. Moreover, the feeding parameters on a large diameter vessel influenced by the crop anticoagulants were evaluated in detail. the anticoagulant activity was significantly higher in the crop contents than in salivary glands, varying from 1.6-fold higher for R. prolixus to 70-fold higher for T. brasiliensis. Amongst the species, T. brasiliensis had the lowest crop anticoagulant activity, the lowest concentration of thrombin inhibitor, and took the longest to feed. Triatoma brasiliensis nymphs that had their intestinal anticoagulant (brasiliensin) knocked down by RNA interference had the lowest capacity to maintain cibarial pump frequency at higher levels throughout the feeding process and consequently a lower ingestion rate (mg/min), even when fed under favourable conditions (large diameter vessel). However, the feeding difficulty for brasiliensin knockdown T. brasiliensis nymphs was reversed by treating the host mice with heparin (a potent systemic anticoagulant) before blood feeding. the results indicate that crop anticoagulant activity influences modulation of the blood-pumping frequency to the intestine and significantly affects the feeding efficiency of triatomine spp. on live hosts. (C) 2011 Australian Society for Parasitology Inc. Published by Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)A non-hemorrhagic hybrid heparin/heparan sulfate with anticoagulant potential(Elsevier B.V., 2014-01-02) Brito, Adriana S.; Cavalcante, Romulo S.; Palhares, Lais C. G. F.; Hughes, Ashley J.; Andrade, Giulianna P. V.; Yates, Edwin Alexander [UNIFESP]; Nader, Helena Bonciani [UNIFESP]; Lima, Marcelo Andrade de [UNIFESP]; Chavante, Suely F.; Univ Fed Rio Grande do Norte; Univ Liverpool; Diamond Light Source Ltd; Universidade Federal de São Paulo (UNIFESP)The structural characterization and the anticoagulant potential of a novel heparin/heparan sulfate-like compound from the heads of Litopenaeus vannamei shrimp are described. While it is distinct from either heparin or heparan sulfate, enzymatic depolymerization and nuclear magnetic resonance spectroscopy analyses revealed that this molecule does share some structural features with heparin, such as the high degree of N- and 6-0-sulfation and minor N-acetylation, and with heparan sulfate, in the glucuronic acid content. Its ability to stabilize human antithrombin explains its significant anticoagulant activity in aPTT and Factor-Xa inhibition assays. Interestingly, in contrast to mammalian heparin, the shrimp compound displayed negligible hemorrhagic effect. Together, these findings have particular interest since they reveal a novel molecule with significant anti-Xa activity coupled with low bleeding effects which make the shrimp heparin/HS-like compound a potential alternative for mammalian heparin. (C) 2013 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosA sulfated polysaccharide, fucans, isolated from brown algae Sargassum vulgare with anticoagulant, antithrombotic, antioxidant and anti-inflammatory effects(Elsevier B.V., 2013-01-02) Dore, Celina Maria Pinto Guerra; Alves, Monique Gabriela das Chagas Faustino; Will, Luiza Sheyla Evenni Pofirio; Costa, Thiago Gomes; Sabry, Diego de Araujo [UNIFESP]; Souza, Leonardo Augusto Rêgo de; Accardo, Camila de Melo [UNIFESP]; Rocha, Hugo Alexandre de Oliveira; Filgueira, Luciana Guimarães Alves; Leite, Edda Lisboa; Univ Fed Rio Grande do Norte; Universidade Federal de São Paulo (UNIFESP)Fucan (SV1) sulfated polysaccharides from the brown algae Sargassum vulgare were extracted, fractionated in acetone and examined with respect to chemical composition, anticoagulant, anti-inflammatory, antithrombotic effects and cellular proliferation. These polysaccharides contain low levels of protein, high level of carbohydrate and sulfate. Monosaccharides analysis revealed that SV1 was composed of fucose, galactose, xylose, glucuronic acid and mannose. SV1 polysaccharide prolonged activated partial thromboplastin time (aPTT) and exhibited high antithrombotic action in vivo, with a concentration ten times higher than heparin activity. PSV1, a purified form in gel filtration showed very low biological activities. SV1 stimulated the enzymatic activity of FXa. Its action on DPPH radical scavenging activity was 22%. This polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different erythrocyte groups. It displays strong anti-inflammatory action at all concentrations tested in the carrageenan-induced paw edema model, demonstrated by reduced edema and cellular infiltration. (C) 2012 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosTick salivary gland as potential natural source for the discovery of promising antitumor drug candidates(Elsevier France-Editions Scientifiques Medicales Elsevier, 2016) Chudzinski-Tavassi, Ana Marisa; Morais, Katia L. P. [UNIFESP]; Pacheco, Mario Thiego Fernandes; Pasqualoto, Kerly Fernanda Mesquita; de Souza, Jean Gabriel [UNIFESP]Nowadays, the relationship between cancer blood coagulation is well established. Regarding biodiversity and bioprospection, the tick biology has become quite attractive natural source for coagulation inhibitors, since its saliva has a very rich variety of bioactive molecules. For instance, a Kunitz-type FXa inhibitor, named Amblyomin-X, was found through transcriptome of the salivary gland of the Amblyomma cajennense. tick. This TFPI-like inhibitor, after obtained as recombinant protein, has presented anticoagulant, antigionenic, and antitumor properties. Although its effects on blood coagulation could be relevant for antitumor effect, Amblyomin-X acts by non-hemostatic mechanisms, such as proteasome inhibition and autophagy inhibition. Notably, cytotoxicity was not observed on non-tumor cells treated with this protein, suggesting some selectivity for tumor cells. Considering the current efforts in order to develop effective anticancer therapies, the findings presented in this review strongly suggest Amblyomin-X as a promising novel antitumor drug candidate. (C) 2015 Elsevier Masson SAS. All rights reserved.
- ItemSomente MetadadadosTick salivary gland as potential natural source for the discovery of promising antitumor drug candidates(Elsevier France-Editions Scientifiques Medicales Elsevier, 2016) Chudzinski-Tavassi, Ana Marisa; Morais, Katia L. P. [UNIFESP]; Pacheco, Mario Thiego Fernandes; Pasqualoto, Kerly Fernanda Mesquita; de Souza, Jean Gabriel [UNIFESP]Nowadays, the relationship between cancer blood coagulation is well established. Regarding biodiversity and bioprospection, the tick biology has become quite attractive natural source for coagulation inhibitors, since its saliva has a very rich variety of bioactive molecules. For instance, a Kunitz-type FXa inhibitor, named Amblyomin-X, was found through transcriptome of the salivary gland of the Amblyomma cajennense. tick. This TFPI-like inhibitor, after obtained as recombinant protein, has presented anticoagulant, antigionenic, and antitumor properties. Although its effects on blood coagulation could be relevant for antitumor effect, Amblyomin-X acts by non-hemostatic mechanisms, such as proteasome inhibition and autophagy inhibition. Notably, cytotoxicity was not observed on non-tumor cells treated with this protein, suggesting some selectivity for tumor cells. Considering the current efforts in order to develop effective anticancer therapies, the findings presented in this review strongly suggest Amblyomin-X as a promising novel antitumor drug candidate. (C) 2015 Elsevier Masson SAS. All rights reserved.