623 resultados para Polissacarídeos sulfatados. Fucanas. Nanogéis. Atividadeantitumoral. Citotoxicidade


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This study aimed to extract, characterize and conduct a prospective analysis of pharmacological activities of sulfated polysaccharides from green seaweed Caulerpa prolifera. Seven fractions (CP-0.3/CP-0.5/CP-0.7/CP-0.9/CP-1.1/CP-1.5/CP-2.0) were obtained from C. prolifera by alkaline proteolysis followed by sequential precipitation in acetone. The physicochemical analyzes indicated that C. prolifera synthesizes a homogalactan (CP-0.9) and different populations of sulfated heteropolysaccharides. In the analysis of anticoagulant activity, all fractions except CP-0.3, influenced the intrinsic coagulation pathway. All fractions showed antioxidant activity in six different assays being more pronounced in hydrogen peroxide scavenging assay, especially CP-0.3, CP-0.7 and CP-0.9 (which obtained 61% of hydrogen peroxide scavenging), in ferric chelation assay (especially CP-0.9 with 56% chelation) and cupric chelation assay (especially CP-2.0 with 78% chelation). With respect to immunomodulatory activity, the presence of CP-0.3, CP-0.7 and CP-0.9 showed an immunogenic potential, increasing the production of nitric oxide (NO) by 48, 142 and 163 times, respectively. Conversely, the NO synthesis fell 73% after the activation of macrophages by LPS, incubated concurrently with CP-2.0. The anti-adipogenic activity of the fractions was also evaluated and CP-1.5 was able to reduce the differentiation of pre-adipocytes (3T3-L1) into adipocytes by 60%, without affecting the cell viability. The fractions CP-0.3, CP-0.5 and CP-0.9 reduced the viability of the HeLa cells (human cervical adenocarcinoma) by 55% and CP-1.5 reduced the viability of the 786-0 cells (human renal adenocarcinoma) by 75%. Leishmanicidal activity and microbicide effect against Carbapenem-resistant Klebsiella pneumoniae (KPC) have not been identified. However, the viability of Staphylococcus epidermidis was reduced by 23.8% in the presence of CP -1.5. All fractions were able to change the formation of calcium oxalate crystals. CP-0.3, CP-0.5 and CP-1.1 only promoted the formation of COD type crystals with a very small size (1 μm). Confocal microscopy and zeta potential data of crystals formed in the presence of the samples showed that the polysaccharides present in the fractions must interact with calcium ions present throughout the crystal lattice, affecting the growth and morphology of crystals The results described herein indicate that the fractions rich in polysaccharides obtained from the green seaweed C. prolifera present a multi therapeutic potential, and subsequent purification steps, as well as research on the mechanisms of action by which these polymers act should be investigated.

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In recent years, sulfated polysaccharides (SP) from marine algae have emerged as an important class of natural biopolymers with potential pharmacology applications. Among these, SP isolated from the cell walls of red algae have been study due to their anticoagulant,antithrombotic and anti-inflammatory activities. In the present study, three sulfated polysaccharides fractions denominated F1.5v, F2.0v and F3.0v were obtained from seaweed G. caudate by proteolysis followed to acetone fractionation. Gel electrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9,0, stained with 0.1% toluidine blue, showed the presence of SP in all fractions. The chemical analysis demonstrated that all the fractions are composed mainly of galactose. These compounds were evaluated in anticoagulant, antioxidant and antiproliferative activities. In anticoagulant activity evaluated through aPTT and PT tests, no one fractions presented anticoagulant activity at tested concentrations (0.1 mg/mL; 1.0 mg/mL; 2.0 mg/mL).The antioxidant activities of the three fractions were evaluated by the following in vitro systems: Total antioxidant capacity, superoxide and hydroxyl radical scavenging, ferrous chelating activity and reducing power. The fractions were found to have different levels of antioxidant activity in the systems tested. F1.5v shows the highest activity, especially in the ferrous chelating system, with 70% of ferrous inhibiting at 1.0 mg.mL-1. Finally, all the fractions showed dose-dependent antiproliferative activity against HeLa cells. The fractions F1.5v and F2.0v presented the highest antiproliferative activity at 2.0 mg/mL with 42.7% and 37.0% of inhibition, respectively. Ours results suggests that the sulfated polysaccharides from seaweed G. caudata are promising compounds in antioxidant and/or antitumor therapy

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Sulfated polysaccharides (PS) are biomolecules with a great biotechnological potential. There are few data about PS from high plants. In addition, pharmacological activities of PS from plants have not been carrying out. The aim of this work was extract PS from the angiosperm Halodule wrightii and study their anticoagulant and antioxidant activities. Histological analysis showed the presence of the PS manly in the roots. A polysaccharide-rich extract was obtained from H. wrightii by proteolysis followed by methanol and TCA precipitation. Chemical, infra-red analysis and agarose gel electrophoresis in 1.3 diaminopropane acetate buffer confirmed the presence of sulfated polysaccharides made by glucose, galactose, xylose and sulfate residues in the proportion 1: 0,9: 1: 1. In addition polyacrilamide electrophoresis have shown that extract is mainly compose by 11kDa sulfated polysaccharides. Pharmacological analysis have shown total antioxidant capacity (CAT) that resulted in 15,21 μg for equivalent of ascorbic acid, scavenging activity of the DPPH radical with 41,36 % of scavenging, activity of reducing power with the maximum of 0,290 nm (50 % of vitamin C activity) and scavenging activity superoxide radical (O2-) with a maximum of 32,23 %. Chelating activity of metal less than 4% and scavenging activity of the radical hydroxyl (OH-) less than 2%. Time of activated partial tromboplastin (aPTT) doubling the time of coagulation from 20μg of and protrombin time (PT) was not present. The data indicate that PS from Halodule wrightii could be considered for future applications in medicine, food production or cosmetic industry

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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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Sulfated Polysaccharides with unique chemical structures and important biological activities has been found in a diversity of sea invertebrates. For that, to exist a huger interest on the biotechnology field in the research theses sulfated compounds isolated from sea organisms. Despite the privileged brazilian position for these compounds attainment, there are still a few scientific informations about the isolated substances and their biological activities. A head the displayed, the present work has for objectives, to evaluate the pharmacological properties of the glycosaminoglycans isolated from the sea shrimp Litopenaeus schimitti on homeostasis, blood coagulation, leukocytes migration and platelet/leukocyte adhesion. For this, yhe glycosaminoglycans were extracted from crustacean tissues by proteolysis, fractionation with acetone and later submitted to pharmacological assays. The crustacean tissues showed compounds heparin-like, with anticoagulant activity of 45 IU/mg and 90 IU/mg, respectively. These molecules showed low residual hemorrhagic effects in the tested concentration (100 µg/mL), when compared to unfractionated commercial heparin (UFH). Another dermatan sulfate-like compound, predominately constituted for disulfated disaccharides, was isolated from crustacean abdomen. This compound showed an efficient effect on leukocytes migration inhibition, in the concentration of 15 µg/mL, reducing the cellular infiltration in 65% when compared to the controlled animals. In this same concentration, the DS reduced in 60% the protein concentration of the peritoneal exudates. In the concentration, this compound of 0.5 mg/mL, it was capable to reduce in 40% platelet/leukocytes adhesion. Our data demonstrate that these sulfated polysaccharides isolated from the shrimp L. schimitti will can be used as bioactive compounds, appearing as active principles for pharmacological development, anticoagulants and inflammatory response regulators

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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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Fucans, sulfated polysaccharides extracted from brown algae and some echinoderms, have been extensively studied for its diverse biological activities and because of its interference with molecular mechanisms of cell to cell recognition, including leukocyte trafficking from blood vessels into sites of inflammation mediated by selectin, a family of adhesion molecules. In the present study, we examined structural features of a heterofucan extracted from brown algae Padina gymnospora and its effect on the leukocyte migration to the peritoneum. The sulfated polysaccharides were extracted from the brown seaweed by proteolysis with the proteolytic enzyme maxatase. The presence of protein and uronic acid contamination was detected in the crude polysaccharide extract. Fractionation of the crude extract with growing concentrations of acetone produced five fractions with different concentrations of fucose, xylose, uronic acid, galactose, glucose and sulfate. The fraction precipitated with 1.5 volumes of acetone was characterized by infrared and nuclear magnetic resonance, through which can be observed the presence of sulfate groups in the C4 of -L-fucose. The anti-inflammatory action of this composite was assessed by a sodium thioglycollate-induced peritonitis assay and through nitric oxide production by the peritoneal macrophages using Griess reagent. Fraction F1.5 was efficient in reducing leukocyte influx into the peritoneal cavity when 10 mg/kg and 25mg/kg were used, resulting in a decrease of 56 and 39%, respectively. A decrease of nitric oxide production occurred when high concentrations of fucana were used. The cytotoxicity of the composite was also assessed using the reduction of 3-(4,5 dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT). Fraction F1.5 had no cytotoxicity when 500 μg/mL of the fraction was used. This study suggests the use of fraction F1.5 (heterofucan) as an anti-inflammatory

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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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Para formar metástases, as células tumorais devem se desprender do tumor primário e migrar através do endotélio num processo denominado intravasamento. Uma vez na circulação, elas devem aderir ao endotélio do tecido alvo e extravasar para o novo sítio de colonização, onde irão proliferar. A interação das células tumorais com o endotélio é mediada por selectinas, seguida pela interação com integrinas. As células tumorais apresentam um padrão anormal de glicosilação, expressando ligantes de selectinas, formados por polissacarídeos fucosilados, como sialyl Lewis a/x. Durante o processo metastático, células tumorais secretam diversos fatores de crescimento. Além de modular diferentes tipos celulares que constituem o microambiente tumoral, estes fatores de crescimento também atuam nas células tumorais de forma autócrina, ativando vias de sinalização envolvidas na proliferação e migração celular. Polissacarídeos sulfatados como a heparina, podem atuar como inibidores de P e L-selectinas, além de se ligar a fatores de crescimento, impedindo a ativação de seus receptores. Neste trabalho, avaliamos o papel de fucanas sulfatadas extraídas de diferentes espécies de invertebrados marinhos (L. variegatus, S. franciscanus, S. pallidus, A. lixula e S. droebachiensis) na modulação da interação entre células tumorais com o endotélio in vitro e comparamos seu efeito com o da heparina. Também avaliamos o papel destas moléculas na proliferação de células tumorais. Para isso, utilizamos duas linhagens tumorais de próstata (DU-145 e PC-3) e culturas primárias de células endoteliais de veia umbilical humana (HUVECs). Ao avaliar o efeito das fucanas na adesão das células tumorais às HUVECs, observamos que todas as fucanas testadas inibiram a adesão da linhagem DU-145 à monocamada endotelial, enquanto apenas a fucana extraída da espécie L. variegatus (FucSulf I) e da espécie S. franciscanus inibiram a adesão da linhagem PC-3. A FucSulf I foi uma das fucanas que apresentou maior potencial inibitório nas duas linhagens e foi a única que inibiu a adesão da linhagem DU-145 à matriz subendotelial, não interferindo na adesão da linhagem PC-3. A FucSulf I mostrou-se capaz de diminuir também a migração transendotelial das linhagens tumorais DU-145 e PC-3. A heparina mostrou efeito significativo apenas nos ensaios de transmigração, inibindo este evento de forma similar a FucSuf I. Sabe-se que o VEGF aumenta a permeabilidade endotelial, facilitando a passagem de células tumorais através do vaso. Observamos que as duas linhagens secretam VEGF e que a FucSulf I se liga a este fator. Estes dados sugerem que a interação da FucSuf I com o VEGF pode impedir a ação deste fator nas células endoteliais, diminuindo a migração transendotelial das células tumorais testadas. Também verificamos que a FucSulf I inibiu a proliferação das linhagens celulares na ausência de fatores exógenos ou na presença de soro fetal bovino ou VEGF. Por fim, avaliamos que a FucSulf I interfere na ativação de proteínas específicas de vias de sinalização disparadas por fatores de crescimento. A FucSulf I inibe a ativação da AKT na linhagem PC-3, enquanto nas células DU-145 observamos uma inibição da ativação da ERK. Esses dados indicam que a FucSulf I modula diversas etapas da progressão tumoral e pode ser um potencial candidato para o uso em terapias antitumorais

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Sulfated polysaccharides (PS) are biomolecules with a great biotechnological potential. There are few data about PS from high plants. In addition, pharmacological activities of PS from plants have not been carrying out. The aim of this work was extract PS from the angiosperm Halodule wrightii and study their anticoagulant and antioxidant activities. Histological analysis showed the presence of the PS manly in the roots. A polysaccharide-rich extract was obtained from H. wrightii by proteolysis followed by methanol and TCA precipitation. Chemical, infra-red analysis and agarose gel electrophoresis in 1.3 diaminopropane acetate buffer confirmed the presence of sulfated polysaccharides made by glucose, galactose, xylose and sulfate residues in the proportion 1: 0,9: 1: 1. In addition polyacrilamide electrophoresis have shown that extract is mainly compose by 11kDa sulfated polysaccharides. Pharmacological analysis have shown total antioxidant capacity (CAT) that resulted in 15,21 μg for equivalent of ascorbic acid, scavenging activity of the DPPH radical with 41,36 % of scavenging, activity of reducing power with the maximum of 0,290 nm (50 % of vitamin C activity) and scavenging activity superoxide radical (O2-) with a maximum of 32,23 %. Chelating activity of metal less than 4% and scavenging activity of the radical hydroxyl (OH-) less than 2%. Time of activated partial tromboplastin (aPTT) doubling the time of coagulation from 20μg of and protrombin time (PT) was not present. The data indicate that PS from Halodule wrightii could be considered for future applications in medicine, food production or cosmetic industry

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Fucan is a term used to denominate a family of sulfated polysaccharides rich in L-fucose. They are extracted mainly from the extracellular matrix of brown algae and echinoderms. The brown alga Spatoglossum schröederi (Dictyotaceae) has three heterofucans named A, B and C. Our research group have been extracted non anticoagulant heterofucan from S. schröederi which possess antithrombotic activity in vivo. However, their toxicity in vitro and in vivo has not yet been determined. For the results in toxicity in vitro, we observed that the fucan A at 20, 500 and 1000 μg/plate showed no mutagenic activity in Kado test (Microsuspension), when the bacterial strains TA97a, TA98, TA100 and TA102, with and without S9 were used. The comet assay showed that fucan A (from 20 to 1000 μg/mL) did not cause any genotoxic effect on CHO cells. There was no damage to the DNA of these cells, as evidenced by the tail length and tail moment, which were similar to that found for the negative control. The fucan A from S. schröederi was administered at 20 μg/g of rat (dose which it showed high antithrombotic activity) during two months. After that, the animals were killed and examined. The data showed that fucan A did not cause any change in biochemistry and hematological parameters, as well as, in the morphology and size of the rat s organs analyzed. In conclusion, this study indicates that fucan is a compound with potential pharmacological that has no toxicity

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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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Fucan is a term used to denominate L-fucose rich sulfated polysaccharides. The fucans have been studied due their pharmacological activities like antithrombotic, antiproliferative and antioxidant. We have extracted three fucan fractions from the brown seaweed Spatoglossum schröederi. These fucans were denominated Fuc B 1, Fuc B 1.5 and Fuc B 2. The chemical analyzes show that the fucans have very similar composition as demonstrated by agarose electrophoresis gel, sugar and sulfate content. The antiproliferative effect was determined by MTT and BrdU methodologies in CHO cells. The inhibition of proliferation effect of the three fractions was about 40%. Therefore this we proceed just with the Fuc B 2 due the higher yield. There is no apoptosis indication using the anexin V/propidium iodide test. We found a cell cycle phase G1 arrest. The western blotting show that the PKC; pFAK; pERK 1/2 are activated when the cells were treated with fucans. The treatement with inhibitor of MAPK PD98059 extinguished the fucan effect. These results indicates that fucan act by the ERK pathway inducing the cell death.

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Marine algae are one of the major sources of biologic compounds. In extracellular matrix of these organisms there are sulfated polysaccharides that functions as structural components and provides protection against dehydration. The fraction 1.0 (F1.0) rich in sulfated galactans obtained from red seaweed Hypnea musciformis was physicochemical characterized and evaluated for pharmacologic activity through antioxidant activity, cytotoxic action on erythrocytes, anticoagulant, stimulatory action under antithrombotic heparan sulfate synthesis and their effects on cell proliferation and cycle cell progression. The main components of F1.0 were carbohydrates (49.70 ± 0.10%) and sulfate (44.59 ± 0.015%), presenting phenolic compounds (4.79 ± 0.016%) and low protein contamination (0.92 ± 0.001%). Fraction 1.0 showed polidisperse profile and signs in infrared analysis in 1262, 1074 and 930, 900 and 850 attributed to sulfate esters S=O bond, presence of a 3,6- anidrogalactose C-O bond, non-sulfated β-D-galactose and a C-O-SO4 bond in galactose C4, respectively. The fraction rich in sulfated galactans exhibited strong antioxidant action under lipid peroxidation assay with IC50 of 0.003 mg/mL. Besides the inhibition of hemolysis induced by H2O2 in erythrocytes treated with F1.0, this fraction did not promote significant cytotoxity under erythrocytes membranes. F1.0 exhibited low anticoagulant activity causing moderate direct inhibition of enzimatic activity of thrombin. This fraction promoted stimulation around of 4.6 times on this synthesis of heparan sulfate (HS) by rabbit aortic endothelial cells (RAEC) in culture when was compared with non treated cells. The fraction of this algae displayed antiproliferative action under RAEC cells causing incresing on cell number on S fase, blocking the cycle cell progression. Thus F1.0 presented cytostatic and no cytotoxic action under this cell lineage. These results suggest that F1.0 from H. musciformis have antioxidant potential which is a great effect for a compound used as food and in food industry which could be an alternative to food industry to prevent quality decay of lipid containing food due to lipid peroxidation. These polysaccharides prevent the lipid peroxidation once the fraction in study exhibited strong inhibitory action of this process. Furthermore that F1.0 present strong antithrombotic action promoting the stimulation of antithrombotic HS synthesis by endothelial cells, being important for thrombosis preventing, by its inhibitory action under reactive oxygen species (ROS) in some in vitro methods, being involved in promotion of hypercoagulability state.

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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