20 resultados para aPTT assay

em Universidade Federal do Rio Grande do Norte(UFRN)


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In the present study, extracts rich-sulfated polysaccharides were obtained from three different species of Dictyotales (a class of brown macroalgae): Canistrocarpus cervicornis, Dictyota mertensii and Dictyopteris delicatula and their anticoagulant and antioxidant activities were evaluated. All extracts showed anticoagulant activity on aPTT assay, but not on PT assay. Extracts also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. The extract from C. cervicornis showed the best results and was choose to have their sulfated polysaccharides fractioned and subsequently analysed. Thus, six fractions (CC-0.3, CC-0.5, CC-0.7, CC-1.0, CC-1.2 and CC-2.0) were obtained by proteolysis followed by sequential acetone precipitation. Agarose gel eletrophoresis stained with blue toluidine, confirmed the presence of sulfated polysaccharides in all fractions. Chemical analyses showed that all fractions presented heterofucans mainly constitued by fucose, galactose, glucuronic acid and sulfate. Any fraction changed the PT. However, all fractions were able to double the aPTT on a dose-dependent manner. CC- 0.3, CC-0.5, CC-0.7 and CC-1.0 needed only 0.100 mg/mL to double the aPTT, result only 1.25 times higher than the Clexane® (0.080 mg/mL), a commercial low molecular heparin. The heterofucans presented appreciable total antioxidant capacity, low capacity on scavenging hydroxyl radical and good efficiency on scavenging superoxide radicals (except CC-1.0). CC-1.2 showed 43.1 % on superoxide radical scavenging. This result was higher than that showed by the same concentration of gallic acid (41.8 %), a known antioxidant. Furthermore, the heterofucans showed excelent activity on ferrous chelating activity (except CC-0.3). CC-0.5, CC-0.7 and CC-1.0 showed the highest activities with 47.0 % of ferrous chelating activity, a result 2.0 times lesser than that exhibited by the same concentration of EDTA. These results clearly indicated the beneficial effects of heterofucans extracted from C. cervicornis as potential anticoagulant and antioxidant agents. However additional steps of purification, structural studies, besides in vivo experiments are needed for these fucans may be used as therapeutic agents

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In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula (Lamouroux, 1809) and their anticoagulant, antioxidant and antitumor activities were evaluated. All fractions showed anticoagulant activity on aPTT assay, but not on PT assay. Fractions also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. Thus, six fractions (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) we obtained by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. Any fractions changed the PT. However, all fractions were able on double the aPPT on a dose-dependent manner. The heterofucans F0.7v and F1.0v showed low anticoagulant activity while F1.5v presented the most prominent anticoagulant activity .When compared to Clexane®, a low molecular weight heparin, at same concentration F1.5v presented similar anticoagulant activity. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (~45%), whereas fucans F1.3v (0.5 mg/mL) showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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Prospecting pharmacological active polysaccharides from agricultural byproducts, such as corncobs, is an underexplored practice in the scientific community. Thus, this work aims to expand knowledge about pharmacological activities of polysaccharides extracted from corncobs. From corn cob flour a extract was obtained by ultrasound waves in an alkaline medium, and the end of the process the product was termed PECC (polysaccharidic extract from corncobs). This extract was physicochemical characterized and evaluated by in vitro assays as an antioxidant, cytotoxic, anticoagulant and imunomodulator agent. Results indicated significant activity metal chelating by PECC, and the use of PECC in cell culture cells showed no toxic effects to normal cell lines, but toxic action against HeLa tumor cells due promoting cell death by apoptosis. In addition, other pharmacological effects were observed, the PECC decreased nitric oxide (NO) production by activated macrophages, and prolonged blood clotting time through APTT assay. Then methanolic, ethanolic and ketone fractions were obtained from fractionation of PECC polysaccharides. Five methanolic fractions, six ethanolic fractions and two ketones were obtained; and all fractions were evaluated for antioxidant, cytotoxic, anticoagulant, immunomodulatory activities. E1.4 fraction exhibited significant metal chelating effect, a toxic action to induce apoptosis in HeLa cells, decreased NO production by activated macrophages, and extended blood clotting time. These results showed that the PECC pharmacological active polysaccharides would be present in the fraction E1.4. From fractionation of E1.4 polysaccharide six subfractions with different sizes were obtained: <3; 3-10; 10-30; 30-50; 50-100 and >100 KDa. About 80% of E1.4 polysaccharides had lower size to 10 KDa, and all the subfractions showed over 61% sugar in their chemical compositions. These subfractions exhibited different monosaccharide compositions, but xylose was presented in all of them. The subfractions exhibited distinct pharmacological effects in in vitro assays. Smaller subfractions (<30 KDa) had highest metal chelating activity and greater toxic action in tumor cells. The intermediate fractions (between 30-100 KDa) decreased more NO production of activated macrophages, for other side, the larger size (>100 KDa) modulated a greater number of inflammatory cytokines, and the had greatest anticoagulant effect. Therefore, when analyzing all the results together it is evident that the PECC pharmacological polysaccharides are heteroxylans, and were concentrated in E1.4 fraction, and heteroxilanas pharmacological effects depends on their molecular size. Thus, corncobs could be used as source from molecules with biotechnology potential

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Red marine algae of the genus Gracilaria synthesize sulfated polysaccharides (PS) bioactive. But many of these PS were not properly assessed, as is the case of PS synthesized by edible seaweed Gracilaria birdiae. Previous studies showed that sulfated galactans this alga has anti-inflammatory effect. In this work, a galactan (GB) of G. birdiae was obtained and evaluated by different tests. GB showed anticoagulant activity in APTT assay. GB showed no toxicity to normal cells (3T3), but inhibited the survival of cells of adenocarcinoma of the cervix (HeLa) and human pancreatic cancer (Panc-1) 80% (1.5 mg / ml). GB was not able to hijack the OH radical or the superoxide radical. However, showed activity electron donor in two different tests and presented iron chelator activity (70% and 1.0 mg / ml) and Copper (70% at 0.5 mg / ml). The presence of a higher GB promotes formation of crystals of calcium oxalate dihydrate small size, which is less aggressive, because GB is able to interact with and stabilize the crystal that form. Furthermore, GB (2.0 mg / mL) was not cytotoxic to human renal cells (HEK-293). The data lead us to propose that GB has a great potential for the treatment of urolithiasis

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Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

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Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

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Inflammation is combined of a vascular and a cellular reaction, resulting in different cells and tissue responses, both the intravascular and extravascular environment. As the inflammatory process occurs, coagulation proteases, in particular thrombin (FIIa), are able to initiate various cellular responses in vascular biology and therefore is often observed activation of other biological systems, leading to complications during an event inflammatory, such as thrombosis and angiogenesis. Thus, antagonists molecules of these events are interesting models for the development of novel anti-inflammatory drugs. Thereby, it is worth stressing the glycosaminoglycans (GAGs), which are able to interact with several proteins involved in important biological processes, including inflammation and coagulation. Therefore, this study aimed to evaluate the anti-inflammatory, antithrombotic and anti-angiogenic potentials, as well anticoagulant of a dermatan sulfate-like GAG (DS) extracted from the Litopenaeus vannamei cephalotorax. The compound was obtained after proteolysis and purification by ion-exchange chromatography. After total digestion by DS-like compounds digesting lyases (chondroitinase ABC), the DS-like nature was revealed, and then called DSL. The shrimp compound showed reduced anticoagulant effect by the aPTT assay, but high anti-IIa activity, directly and through heparin cofactor II. On inflammation, the compound had a significant inhibitory effect with the reduction of proinflammatory cytokines. Potential Inhibitory were reported in the antithrombotic and anti-angiogenic assay, the latter being dose dependent. As for anti-hemostatic activity, the polysaccharides did not induced significant bleeding effect. Thus, the results shown by the shrimp DS-like compound indicate this glycosaminoglycan as a biotechnology target with prospects for the development of new multipotent drugs.

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In the present study, extracts rich-sulfated polysaccharides were obtained from three different species of Dictyotales (a class of brown macroalgae): Canistrocarpus cervicornis, Dictyota mertensii and Dictyopteris delicatula and their anticoagulant and antioxidant activities were evaluated. All extracts showed anticoagulant activity on aPTT assay, but not on PT assay. Extracts also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. The extract from C. cervicornis showed the best results and was choose to have their sulfated polysaccharides fractioned and subsequently analysed. Thus, six fractions (CC-0.3, CC-0.5, CC-0.7, CC-1.0, CC-1.2 and CC-2.0) were obtained by proteolysis followed by sequential acetone precipitation. Agarose gel eletrophoresis stained with blue toluidine, confirmed the presence of sulfated polysaccharides in all fractions. Chemical analyses showed that all fractions presented heterofucans mainly constitued by fucose, galactose, glucuronic acid and sulfate. Any fraction changed the PT. However, all fractions were able to double the aPTT on a dose-dependent manner. CC- 0.3, CC-0.5, CC-0.7 and CC-1.0 needed only 0.100 mg/mL to double the aPTT, result only 1.25 times higher than the Clexane® (0.080 mg/mL), a commercial low molecular heparin. The heterofucans presented appreciable total antioxidant capacity, low capacity on scavenging hydroxyl radical and good efficiency on scavenging superoxide radicals (except CC-1.0). CC-1.2 showed 43.1 % on superoxide radical scavenging. This result was higher than that showed by the same concentration of gallic acid (41.8 %), a known antioxidant. Furthermore, the heterofucans showed excelent activity on ferrous chelating activity (except CC-0.3). CC-0.5, CC-0.7 and CC-1.0 showed the highest activities with 47.0 % of ferrous chelating activity, a result 2.0 times lesser than that exhibited by the same concentration of EDTA. These results clearly indicated the beneficial effects of heterofucans extracted from C. cervicornis as potential anticoagulant and antioxidant agents. However additional steps of purification, structural studies, besides in vivo experiments are needed for these fucans may be used as therapeutic agents

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The coast of Rio Grande do Norte has more than 100 species of seaweed, mostly unexplored regarding their pharmacological potential. The sulfated polysaccharides (PS) are by far the more seaweed compounds studied, these present a range of biological properties, such as anticoagulant activity, anti-inflammatory, antitumor and antioxidant properties. In this study, we extract sulfated polysaccharide rich-extracts of eleven algae from the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum filipendula; Spatoglossum schröederi; Gracilaria caudata; Caulerpa cupresoides; Caulerpa prolifera; Caulerpa sertularioides e Codim isthmocladum), and these were evaluated for the potential anticoagulant, antioxidant and antiproliferative. All polysaccharide extracts showed activity for anticoagulant, antioxidant and/or antiproliferative activity, especially D. delicatula and S. filipendula, which showed the most prominent pharmacological potential, thereby being chosen to have their sulfated polysaccharides extracted. By fractionating method were obtained six fractions rich in sulfated polysaccharides to the algae D. delicatula (DD-0,5V, DD-0, 7V, DD-1,0v, DD-1,3v, DD-1,5v and DD-2,0) and five fractions to the alga S. filipendula (SF-0,5V, SF-0,7V, SF-1,0v, SF-1,5v and SF-2,0v). For the anticoagulant assay only the fractions of D. delicatula showed activity, with emphasis on DD-1, 5v that presented the most prominent activity, with APTT ratio similar to clexane® at 0.1 mg/mL. When evaluated the antioxidant potential, all fractions showed potential in all tests (total antioxidant capacity, hydroxyl and superoxide radicals scavenging, ferrous chelation and reducing power), however, the ability to chelate iron ions appears as the main mechanism antioxidant of sulfated polysaccharides from seaweed. In antiproliferative assay, all heterofucanas showed dose-dependent activity for the inhibition of cell proliferation of HeLa, however, with the exception of SF-0,7V, SF- 1,0v and SF-1,5v, all fractions showed antiproliferative activity against MC3T3, a normal cell line. The heterofucana SF-1,5V had its antiproliferative mechanism of action evaluated. This heterofucan induces apoptosis in HeLa cells by a pathway caspase independent, promoting the release of apoptosis Inducing Factor (AIF) in the cytosol, which in turn induces chromatin condensation and DNA fragmentation into 50Kb fragments. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer.

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The present study examines the chemical composition and their effects on free radicals, inflammation, angiogenesis, coagulation, VEGF effects and cellular proliferation of a polysaccharides from alga Sargassum vulgare. The sulfated polysaccharide was extracted from brown seaweed by proteolysis with enzymes maxataze. The presence of proteins and sugars were observed in crude polysaccharides. Fractionation of this crude extract was made with growing concentration of acetone (0.3-1.5 v) and produced four groups of polysaccharides. Anionic polysaccharides from brown seaweed Sargassum vulgare, SV1and PSV1 were fractionated (SV1) and purified (PSV1), and displayed with high total sugars and sulfate content and very low level of protein. This fucan SV1 contains low levels of protein and high carbohydrate and sulfate content. This polysaccharides prolonged activated partial thromboplastin time (aPTT) at 50 μg (>240 s). SV1 was found to have no effect on prothrombin time (PT), corresponding to the extrinsic pathway of coagulation. SV1 exhibits high antithrombotic action in vivo, with a concentration ten times higher than heparin. Polysaccharides from S. vulgare promoted direct inhibition enzymatic activity of thrombin and stimulated enzymatic activity of FXa. SV1 showed optimal inhibitory activity of thrombin (50.2±0.28%) at a concentration of 25 μg/mL. Its antioxidant action on scavenging radicals by DPPH was (22%), indicating the polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different erythrocyte groups and displays strong anti-inflammatory action on all concentrations tested in the carrageenan-induced paw edema model, demonstrated by reduced edema and cellular infiltration. Angiogenesis is a dynamic process of proliferation and differentiation. It requires endothelial proliferation, migration, and tube formation. In this context, endothelial cells are a preferred target for several studies and therapies. The antiangiogenic efficacy of polysaccharides was examined in vivo in the chick chorioallantoic membrane (CAM) model by using fertilized eggs. Decreases in the density of the capillaries were assessed and scored. The results showed that SV1 and PSV1 have an inhibitory effect on angiogenesis. These results were also confirmed by inhibition tubulogenesis in rabbit aorta endothelial cell (RAEC) in matrigel. These compounds were assessed in Apoptosis assay (Annexin V - FITC / PI) and cell viability by MTT assay of RAEC. These polysaccharides do not affect the viability and do not have apoptotic or necrotic action. RAEC cell when incubated with SV1 and PSV1showed inhibition of VEGF secretion, observed when compounds were incubated at 25, 50 and 100 μg/μL. The VEGF secretion with the RAEC cell line for 24 h, was more effective for PSV1 at 50 μg/μL(71.4%) than SV1 100 μg/μL (75.9%). SV1 and PSV1 had an antiproliferative action (47%) against tumor cell line HeLa. Our results indicate that these sulfated polysaccharides have antiangiogenic and antitumoral actions

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Galactans are polysaccharides sulfated present in the cell wall of red algae. Carrageenans are galactans well known in the food industry as gelling polysaccharides and for induce inflammatory process in rodents as animal model. The extraction of polysaccharides from A. multifida has been carried out by proteolysis and precipitation in different volumes of acetone, which produced three fractions (F1, F2, and FT). Chemical and physical analyses revealed that these fractions are sulfated galactan predominantly. Results of the antioxidant activity assays showed that all of these fractions have antioxidant activity and that was associated with sulfate content of the analysis of reducing power and total antioxidant capacity. However, these fractions were not effective against lipid peroxidation. The fraction FT presented higher activity on the APTT test at 200 μg (> 240 s). The assessment of the hemolytic activity showed that the FT fraction has the best activity, increasing lyses by the complement system to 42.3% (50 μg) (p< 0,001). The fraction FT showed the best yield, anticoagulant and hemolytic activity between the three fractions and therefore it was choose for the in vivo studies. The Inflammation assessment using the FT fraction (50 mg / kg MB) showed that the cellular migration and the IL-6 production increased 670.1% (p< 0,001) and 531.8% (p< 0,001), respectively. These results confirmed its use as an inflammation inducer in animal model. Cytotoxicity assay results showed that all fractions have toxic effects on 3T3 and HeLa cells after exposition of 48 hours, except when 100 μg for both F1 and FT were used. These results arise the discussion whether these polysaccharides it should be used as additive in foods, cosmetics and medicines.

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Fucans are a family of sulfated homo and teropolysaccharides respectively, composed mainly of a- (1®2) and a- (1®3) linked by L-fucose residues. Properties such as the ability to act as an anti-contraceptive, to reduce cholesterol levels, and to act as an anti-tumor agent are much related. We have focused our attention on the anticoagulant properties, platelet aggregation, hemorrhagic activity and complement system in vitro of commercial fucoidan (F) and their purified fractions (F1, F2 and F3) from Fucus vesiculosus obtained from fractionation of the fucoidan with different concentrations of acetone 1, 2 and 3v. These compounds were chemically characterized and the fucoidan (F) was modified by desulfation. The anticoagulant activity of the compounds was assessment by activated partial thromboplastin time (APTT) and prothrombine time assay (PT) using citrated normal human plasma. The results of APPT test showed that F, F1 and F2 have high anticoagulants activities 240.0 s (5 µg). The F3 showed 73.7 s in the same concentrations. The results obtained with PT test to F, F1, F2 and F3 were 81.5 s, 120.0 s, 57.1 and 32.5 s respectively with 50 µg. The dessulfated polymer showed a decrease in the anticoagulant activity in these two tests. Platelet aggregation assay was measured turbidimetrically with platelet aggregometer by method of Born. The aggregation platelet with F and fractions F1, F2 and F3 exhibited a two-phase answer in the concentration of 5 mg/mL with maximum aggregation of 76.36 ± 10.3% ; 69.54 ± 9.40%; 75.94 ± 9.01%; 51.13 ± 9.59% respectively. However, was observed a hipoaggregate profile F (15.17 ± 5.2%), F1 (7.40 ± 3.04 %), F2 (19.1 ± 5.41%) and F3 (5.09 ± 3.02%) at 0.1 mg/mL. The hemorrhagic activity assay was carried in Wistar rats and showed that these compounds have low hemorrhagic effect when compared to heparin. The complement system ( alternative pathway was made using non-sensibilized rabbit red blood cells The results of complement system essay showed that F , F2 and F3 have action inhibitory in relation to the group control 0.544, 0.697, 0.622 and 0.958 respectively The results showed that these compounds have action on this system. Interaction of the polisaccharides with proteins C3 and C4 showed that the fraction F1 stimulated the activity assay hemolytic using red blood cells

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Seaweeds are a major source of biologically active compounds . In the extracellular matrix of these organisms are sulfated polysaccharides that functions as structural components preventing it against dehydration. The fraction 0.9 (FucB) rich in sulfated fucans obtained from brown seaweed Dictyota menstrualis was chemical characterized and evaluated for pharmacological activity by testing anticoagulant activity, stimulatory action on the synthesis of an antithrombotic heparan sulfate, antioxidant activity and its effects in cell proliferation. The main components were FucB carbohydrates (49.80 ± 0.10 %) and sulfate (42.30 ± 0.015 %), with phenolic compounds ( 3.86 ± 0.016 %) and low protein contamination ( 0.58 ± 0.001 % ) . FucB showed polydisperse profile and analysis of signals in the infrared at 1262, 1074 and 930 cm -1 and 840 assigned to S = O bonds sulfate esters , CO bond presence of 3,6- anhydrogalactose , β -D- galactose non- sulfated sulfate and the axial position of fucose C4 , respectively. FucB exhibited moderate anticoagulant activity , the polysaccharides prolonged time (aPTT ) 200 ug ( > 90s ) partial thromboplastin FucB no effect on prothrombin time (PT), which corresponds to the extrinsic pathway of coagulation was observed. This stimulation promoted fraction of about 3.6 times the synthesis of heparan sulfate (HS) by endothelial cells of the rabbit aorta ( RAEC ) in culture compared with cells not treated with FucB . This has also been shown to compete for the binding site with heparin. The rich fraction sulfated fucans exhibited strong antioxidant activity assays on total antioxidant (109.7 and 89.5 % compared with BHT and ascorbic acid standards ) , reducing power ( 71 % compared to ascorbic acid ) and ferric chelation ( 71 , comparing with 5 % ascorbic acid). The fraction of algae showed cytostatic activity on the RAEC cells revealed that the increase of the synthesis of heparan sulfate is not related to proliferation. FucB showed antiproliferative action on cell lines modified as Hela and Hep G2 by MTT assay . These results suggest that FucB Dictyota menstrualis have anticoagulant , antithrombotic , antioxidant potential as well as a possible antitumor action, promoting the stimulation of the synthesis of antithrombotic HS by endothelial cells and is useful in the prevention of thrombosis, also due to its inhibitory action on species reactive oxygen ( ROS ) in some in vitro systems , being involved in promoting a hypercoagulable state

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Marine algae are rich sources of various structural compounds which recently has been increasingly studied as a new source of bioactive substances. The alginate, as come as fucans, are considered the main acidic polysaccharides found in brown seaweed. This molecule consists a linear natural polysaccharide, non-sulfated, and presents monosaccharides: acid β-D-mannuronic (M) and α-L-guluronic acid (G); in a vast amount compositions and threads. Alginate has been widely applied in food and pharmaceutical industries because of its ability to retain water, forming films and gels as well as thickening, stabilizing and form emulsions. In this work we aimed to extract, structurally characterize, compare and analyze the possible pharmacological activities of native alginate molecule obtained from brown seaweed Dyctiopteris delicatula (DYN), and its chemically sulfated derivative (DYS). The alginate structure and composition molecule can be proven through chemical dosing, that showed low protein contamination and high sugar level, existence and separation of M and G blocks in the descending paper chromatography, infrared spectroscopy and nuclear magnetic resonance. Molecule sulfation was proven with sulphate dosage, resulting in 28.56% sulphate in molecule; electrophoresis, verify metachromasia with toluidine blue; and infrared spectroscopy, that showed a characteristic band at 1221cm-1 corresponding a sulfate group vibration. For the pharmacological activities the tests was: antioxidant activity, changes in cell function (MTT test) and anticoagulant test. In the antioxidant activity we observed that DYN showed better results in the kidnapping of hydroxyl radicals and ferric chelation compared to DYS, this had the best result in the total antioxidant capacity. Both showed similar activity in reducing power and the kidnapping radicals DPPH. In MTT test DYN and DYS had not proliferative and cytotoxic activity in fibroblast cells (3T3) and showed antiproliferative and cytotoxic activity in cancer cell lines HeLa and B16 melanoma. In anticoagulant assay DYN showed good activity in the intrinsic pathway of blood coagulation, and a small activity in the extrinsic pathway, in the other hand DYS showed only a very small activity in the extrinsic pathway, but cannot come to be regarded as an anticoagulant agent. From these results it can be concluded that the alginate was extracted and sulfated, revealing a potential compound to be used in the pharmaceutical industry as an anticoagulant agent, antioxidant and antitumor and the sulfation has not been conclusively important to performance in the tested pharmacological activities