Literatura académica sobre el tema "Fucoidan"
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Artículos de revistas sobre el tema "Fucoidan"
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Gupta, Dhanak, Melissa Silva, Karolina Radziun, Diana C. Martinez, Christopher J. Hill, Julie Marshall, Vanessa Hearnden, Miguel A. Puertas-Mejia y Gwendolen C. Reilly. "Fucoidan Inhibition of Osteosarcoma Cells is Species and Molecular Weight Dependent". Marine Drugs 18, n.º 2 (8 de febrero de 2020): 104. http://dx.doi.org/10.3390/md18020104.
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Fucoidan is a brown algae-derived polysaccharide having several biomedical applications. This study simultaneously compares the anti-cancer activities of crude fucoidans from Fucus vesiculosus and Sargassum filipendula, and effects of low (LMW, 10–50 kDa), medium (MMW, 50–100 kDa) and high (HMW, >100 kDa) molecular weight fractions of S. filipendula fucoidan against osteosarcoma cells. Glucose, fucose and acid levels were lower and sulphation was higher in F. vesiculosus crude fucoidan compared to S. filipendula crude fucoidan. MMW had the highest levels of sugars, acids and sulphation among molecular weight fractions. There was a dose-dependent drop in focal adhesion formation and proliferation of cells for all fucoidan-types, but F. vesiculosus fucoidan and HMW had the strongest effects. G1-phase arrest was induced by F. vesiculosus fucoidan, MMW and HMW, however F. vesiculosus fucoidan treatment also caused accumulation in the sub-G1-phase. Mitochondrial damage occurred for all fucoidan-types, however F. vesiculosus fucoidan led to mitochondrial fragmentation. Annexin V/PI, TUNEL and cytochrome c staining confirmed stress-induced apoptosis-like cell death for F. vesiculosus fucoidan and features of stress-induced necrosis-like cell death for S. filipendula fucoidans. There was also variation in penetrability of different fucoidans inside the cell. These differences in anti-cancer activity of fucoidans are applicable for osteosarcoma treatment.
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Obeidi, Narges, Mohammad Javad Mousavi, Arghavan Hosseinpouri, Hamideh Malekhayati y Elham Ehsandoost. "nticoagulative Effect of Two Species of Brown Algae; Sargassum Angustifolium and Cystoseira Indica". Research in Molecular Medicine 8, n.º 3 (1 de julio de 2020): 125–32. http://dx.doi.org/10.32598/rmm.8.3.1099.3.
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Background: Fucoidans are a group of sulfated fucose-rich polysaccharides that are isolated from brown marine algae and echinoderms, and recently have been found in seagrasses. Fucoidans, as well as their derivatives, have several beneficial biological effects and therapeutic potentials. In the present study, we aimed to evaluate the anticoagulative effects of two species of brown algae, namely Sargassum angustifolium (S. angustifolium) and Cystoseira indica (C. indica). Methods: Fucoidan C and fucoidan S were extracted by an ethanol/water solvent system from S. angustifolium and C. indicia, respectively. The anticoagulative effects of fucoidan C and fucoidan S were tested on 10 normal serum samples by evaluating the rate of thrombin time (PT) and prothrombin time (PTT). Results: Both fucoidan C and fucoidan S significantly increased PTT. However, no significant difference was observed in PT. Fucoidan C had a greater effect on PTT prolongation compared with fucoidan S. Conclusion: Both fucoidans extracted from S. angustifolium and C. indicia can be used as anticoagulants in biotechnology and human disorders.
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Nguyen, Thuan Thi, Maria Dalgaard Mikkelsen, Vy Ha Nguyen Tran, Vo Thi Dieu Trang, Nanna Rhein-Knudsen, Jesper Holck, Anton B. Rasin, Hang Thi Thuy Cao, Tran Thi Thanh Van y Anne S. Meyer. "Enzyme-Assisted Fucoidan Extraction from Brown Macroalgae Fucus distichus subsp. evanescens and Saccharina latissima". Marine Drugs 18, n.º 6 (2 de junio de 2020): 296. http://dx.doi.org/10.3390/md18060296.
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Fucoidans from brown macroalgae (brown seaweeds) have different structures and many interesting bioactivities. Fucoidans are classically extracted from brown seaweeds by hot acidic extraction. Here, we report a new targeted enzyme-assisted methodology for fucoidan extraction from brown seaweeds. This enzyme-assisted extraction protocol involves a one-step combined use of a commercial cellulase preparation (Cellic®CTec2) and an alginate lyase from Sphingomonas sp. (SALy), reaction at pH 6.0, 40 °C, removal of non-fucoidan polysaccharides by Ca2+ precipitation, and ethanol-precipitation of crude fucoidan. The workability of this method is demonstrated for fucoidan extraction from Fucus distichus subsp. evanescens (basionym Fucus evanescens) and Saccharina latissima as compared with mild acidic extraction. The crude fucoidans resulting directly from the enzyme-assisted method contained considerable amounts of low molecular weight alginate, but this residual alginate was effectively removed by an additional ion-exchange chromatographic step to yield pure fucoidans (as confirmed by 1H NMR). The fucoidan yields that were obtained by the enzymatic method were comparable to the chemically extracted yields for both F. evanescens and S. latissima, but the molecular sizes of the fucoidans were significantly larger with enzyme-assisted extraction. The molecular weight distribution of the fucoidan fractions was 400 to 800 kDa for F. evanescens and 300 to 800 kDa for S. latissima, whereas the molecular weights of the corresponding chemically extracted fucoidans from these seaweeds were 10–100 kDa and 50–100 kDa, respectively. Enzyme-assisted extraction represents a new gentle strategy for fucoidan extraction and it provides new opportunities for obtaining high yields of native fucoidan structures from brown macroalgae.
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Dockal, Michael, Susanne Till, Zhenqing Zhang, Sabine Knappe, Sabrina Reutterer, Catherine Quinn, Christoph Redl, Hartmut J. Ehrlich, Friedrich Scheiflinger y Christina Szabo. "Structure-Activity Relationship of Pro- and Anticoagulant Effects of Fucus Vesiculosus Fucoidan". Blood 120, n.º 21 (16 de noviembre de 2012): 3353. http://dx.doi.org/10.1182/blood.v120.21.3353.3353.
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Abstract Abstract 3353 Fucoidans are sulfated polysaccharides extracted from brown algae. Fucoidans have a wide variety of biological activities including pro- and anticoagulant activities, which occur at different concentration ranges. Therefore, fucoidans have also been described as non-anticoagulant sulfated polysaccharides (NASPs, Liu et al. Thromb Haemost 2006; 95:68). Fucoidans have complex structures due to their large molecular weight (Mw), wide Mw distribution, variable degree and pattern of sulfation, diverse monosaccharide composition, branching of the sugar chain and different monomer linkages. This structural complexity challenges identification of the components responsible for fucoidan activities. The aim of the presented study was to fractionate Fucus vesiculosus (F.v.) fucoidan by size and to de- and oversulfate it to obtain compounds of varying Mw or degree of sulfation (DS), respectively. The fucoidans were then to be analyzed for their pro-and anticoagulant activities and structure, and the effect of modified fucoidan on the target protein Tissue Factor Pathway Inhibitor (TFPI) investigated. Two approaches were applied to generate F.v. fucoidan with different structural properties to the original. Firstly, fucoidan was fractionated by size using ultrafiltration. The Mw of the resulting fractions ranged from 8–180 kD. NMR, elemental analysis and HPAEC showed that other structural features, such as sulfate content and monosaccharide composition, were similar to those of the original fucoidan. Thrombin generation (CAT) assays showed an EC50 for procoagulant activity of 0.3–3 μg/mL; aPTT increased by 50% at 4–25 μg/mL. Generally, higher Mw increased procoagulant activity. Below 15 kD, this activity was markedly reduced. The minimum active length of F.v. fucoidan was 70 carbohydrate units. De- and oversulfated F.v. fucoidans were used to investigate the impact of charge on pro- and anticoagulant activities. In the CAT assay, oversulfated fucoidans showed improved procoagulant activity with an EC50 of 0.09–0.12 μg/mL, while desulfated fucoidans demonstrated reduced procoagulant activity compared to the original. A DS of 0.5 was estimated to be the limit for procoagulant activity. Inhibition of TFPI by fucoidan was assessed with a dilute prothrombin time assay (dPT) with added full-length TFPI. TFPI-blocking activity was mainly dependent on the DS and less on the fucoidans' Mw. Interestingly, oversulfation also stimulated an undesired activation of the contact pathway. The presented study determined the minimal structural requirements for procoagulant activity of fucoidan molecules and identified features causing undesired biological effects. Disclosures: No relevant conflicts of interest to declare.
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Fitton, Stringer, Park y Karpiniec. "Therapies from Fucoidan: New Developments". Marine Drugs 17, n.º 10 (9 de octubre de 2019): 571. http://dx.doi.org/10.3390/md17100571.
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Since our last review in 2015, the study and use of fucoidan has extended in several research areas. Clinical use of fucoidan for the treatment of renal disease has become available and human safety studies have been undertaken on radiolabeled fucoidan for the purpose of imaging thrombi. Fucoidan has been incorporated into an increasing number of commercially available supplements and topical treatments. In addition, new measuring techniques are now available to assess the biologically relevant uptake of fucoidans and to assist in production. Microbiome modulation and anti-pathogenic effects are increasingly promising applications for fucoidans, due to the need for alternative approaches to antibiotic use in the food chain. This review outlines promising new developments in fucoidan research, including potential future therapeutic use.
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Van Weelden, Geert, Marcin Bobiński, Karolina Okła, Willem Jan Van Weelden, Andrea Romano y Johanna M. A. Pijnenborg. "Fucoidan Structure and Activity in Relation to Anti-Cancer Mechanisms". Marine Drugs 17, n.º 1 (7 de enero de 2019): 32. http://dx.doi.org/10.3390/md17010032.
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Fucoidan is a natural derived compound found in different species of brown algae and in some animals, that has gained attention for its anticancer properties. However, the exact mechanism of action is currently unknown. Therefore, this review will address fucoidans structure, the bioavailability, and all known different pathways affected by fucoidan, in order to formulate fucoidans structure and activity in relation to its anti-cancer mechanisms. The general bioactivity of fucoidan is difficult to establish due to factors like species-related structural diversity, growth conditions, and the extraction method. The main pathways influenced by fucoidan are the PI3K/AKT, the MAPK pathway, and the caspase pathway. PTEN seems to be important in the fucoidan-mediated effect on the AKT pathway. Furthermore, the interaction with VEGF, BMP, TGF-β, and estrogen receptors are discussed. Also, fucoidan as an adjunct seems to have beneficial effects, for both the enhanced effectiveness of chemotherapy and reduced toxicity in healthy cells. In conclusion, the multipotent character of fucoidan is promising in future anti-cancer treatment. However, there is a need for more specified studies of the structure–activity relationship of fucoidan from the most promising seaweed species.
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Sinurat, Ellya, Endang Saepudin y Fildzah Alfita Qosthalani. "Effect of Hydrolyzed Fucoidan from The Brown Seaweed Sargassum Binderi Sonder Towards Human Breast Cancer T47d Cell Lines". Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 12, n.º 2 (15 de agosto de 2017): 49. http://dx.doi.org/10.15578/squalen.v12i2.275.
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Fucoidan, a sulfated heteropolysaccharide, consists of L-fucose and sulfate ester groups as the main component. Over the past three decades, fucoidan structures and bioactivities have been widely studied. The chemical components (fucose, galactose, small monosaccharides and also the sulfate) and the molecular weights of fucoidans from different brown seaweed species produce different characteristics and structures of fucoidan. The activity of fucoidan against cancer cells has been reported to be affected strongly by their sulfate content and molecular weight. Low-molecular-weight fucoidans tend to have higher solubility and easily penetrate into cancer cells. The objective of this study was to investigate the effect of hydrolyzed of fucoidan on its anti cancer activity againts the breast cancer T47D cells. In this study, the fucoidan from the brown seaweed Sargassum binderi Sonder was extracted using 0.1 N HCl and was depolymerized by acid hydrolysis at various times and concentrations. Result showed that fucoidan hydrolyzed with 1 M trifluoroacetic acid (TFA) for 1.5 hours reached the maximum depolymerization process and resulted in the decrement of molecular weight from 785.12 kDa to 5.79 kDa as well as sulfate content from 18.63% to 8.69%. The IC50 values of fucoidan and low molecular weight fucoidan against the breast cancer T47D cells were 60.03 mg/mL and 182.34 mg/ respectively. This result indicated that the sulfate content of fucoidan probably affected its anticancer bioactivities.
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Dockal, Michael, Erwin Panholzer, Rudolf Hartmann, Hartmut J. Ehrlich y Friedrich Scheiflinger. "A New Procoagulant Mechanism Mediated by Fucoidans". Blood 116, n.º 21 (19 de noviembre de 2010): 4420. http://dx.doi.org/10.1182/blood.v116.21.4420.4420.
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Abstract Abstract 4420 Fucoidans are heterogeneous, polyanionic molecules with procoagulant activities in a wide concentration range. They have been described as non-anticoagulant sulfated polysaccharides (NASP) and shown to improve clotting in FVIII- and FIX-deficient plasma. In vitro characterization has suggested that fucoidans exert their procoagulant activity by inhibiting tissue factor pathway inhibitor (Liu et al. Thromb Haemost 2006; 95:68) and by accelerating thrombin-dependent FVa formation (Mutch et al. J Thromb Haemost 2007; 5 Suppl2). In our study we describe a new, previously unrecognized mechanism by which fucoidans act as procoagulant agents. The procoagulant activity of several fucoidans was characterized by calibrated automated thrombography in tissue factor (TF)-dependent experiments and by using coagulation factor-deficient plasmas. Spiking experiments with purified coagulation factors or inhibitory antibodies verified the mechanism. Stimulation of thrombin generation (TG) by fucoidans requires anionic lipid surfaces like synthetic phospholipid vesicles which contain phosphatidylserine and is TF-dependent (0-20pM). However, stimulatory activity was most pronounced in the absence of TF. Control experiments with corn trypsin inhibitor or FXII-deficient plasma excluded any involvement of the contact system. Plasmas from patients with congenital coagulation factor deficiencies were screened for TG to identify the target coagulation factor by which fucoidans exert their procoagulant activities. In the absence of TF, plasmas deficient in coagulation factors from the common pathway do not support fucoidan-mediated thrombin generation, whereas FVII-deficient plasma does. FXI was identified as the most upstream factor of the intrinsic pathway which is required for fucoidan-stimulated thrombin generation, suggesting it to be the target for the procoagulant activities of fucoidan. Spiking 30nM FXI to FXI-deficient plasma restored fucoidan-mediated TG and addition of polyclonal FXI inhibitory antibodies to normal plasma abrogated TG. Fucoidan-dependent TG did not improve when FXIa (60pM) was added to FXI-deficient plasma, suggesting activation of FXI by fucoidan. The relevance of this mechanism in hemophilia A plasma was studied by addition of low levels of FVIII (0.2-10%) resulting in a FVIII concentration-dependent increase in fucoidan-mediated TG. These results highlight the requirement of a functional intrinsic pathway for this new mechanism of fucoidans. Our findings present FXI activation at low TF concentrations as a possible mechanism for fucoidan. Disclosures: Dockal: Baxter Innovations GmbH: Employment. Panholzer:Baxter Innovations GmbH: Employment. Hartmann:Baxter Innovations GmbH: Employment. Ehrlich:Baxter Innovations GmbH: Employment. Scheiflinger:Baxter Innovations GmbH: Employment.
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Dockal, Michael, Susanne Till, Sabine Knappe, Hartmut J. Ehrlich y Friedrich Scheiflinger. "Anticoagulant Activity and Mechanism of Non-Anticoagulant Sulfated Polysaccharides". Blood 118, n.º 21 (18 de noviembre de 2011): 1208. http://dx.doi.org/10.1182/blood.v118.21.1208.1208.
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Abstract Abstract 1208 Fucoidans are sulfated polysaccharides which are extracted from brown seaweeds and echinoderms and have a wide variety of biological activities. Described as non-anticoagulant polysaccharides (NASPs), they have been demonstrated to improve clotting in FVIII- and FIX-deficient plasma (Liu et al., 2006), making them good candidates for hemophilia treatment. However, fucoidans have also been extensively studied for their anticoagulant effects (Pereira et al., 1999), which usually occur at much higher concentrations than the procoagulant activity. This opens a large procoagulant window where procoagulant activities exceed anticoagulant effects. When analyzed by a global hemostatic thrombin generation assay in hemophilia plasma the onset of procoagulant activity is observed at concentrations as low as 0.01 μg/mL with optimal activity at about 1 μg/mL. Reversal of procoagulant activity is seen at concentrations higher than 10 μg/mL. Fucoidans and other sulfated polysaccharides activate different anticoagulant mechanisms depending on their structural properties. Branched fucoidans extracted from brown algae have been shown to directly inhibit thrombin, while linear fucoidan from echinoderms activates antithrombin III (ATIII) or heparin cofactor II (HCII)-mediated thrombin inhibition (Pereira et al., 1999). Sulfated galactans also have serpin-dependent and -independent anticoagulant activities (Glauser et al., 2009). In this study we analyzed fucoidans from several brown algae species for their anticoagulant properties and mode of action to identify the candidate with the best procoagulant and lowest anticoagulant activity. NASPs from several brown algae species including L. japonica (L.j.), F. vesiculosus (F.v.), and U. pinnatifida (U.p.) showed different anticoagulant activities in an activated partial thromboplastin time (aPTT) assay. U.p. fucoidan was about twice as anticoagulant as the other fucoidan preparations, increasing clotting time by 50% at a concentration of 4 μg/mL. In addition, NASPs were analyzed in ATIII- and HCII-thrombin model assays. L.j. fucoidan activated ATIII-mediated thrombin inhibition, whereas the other fucoidans showed no effect on ATIII. Fucoidans from L.j. and F.v. had a direct effect on thrombin, starting at about 10 μg/mL. By contrast, U.p. fucoidan did not directly affect thrombin. However, all preparations increased HCII-mediated thrombin inhibition at concentrations below 1 μg/mL. This suggests that HCII is the main target for the anticoagulant activity of fucoidans. Nevertheless, we observed substantial differences between the fucoidan candidates which will be correlated to structural properties. Our work describes the assessment of anticoagulant activities of a variety of fucoidan species to better understand their intertwined pro- and anticoagulant effects. This provides important mechanistic insights for the development of hemophilia therapies. Disclosures: Dockal: Baxter Innovations GmbH: Employment. Till:Baxter Innovations GmbH: Employment. Knappe:Baxter Innovations GmbH: Employment. Ehrlich:Baxter Innovations GmbH: Employment. Scheiflinger:Baxter BioScience: Employment.
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Silchenko, Artem S., Anton B. Rasin, Anastasiya O. Zueva, Mikhail I. Kusaykin, Tatiana N. Zvyagintseva, Anatoly I. Kalinovsky, Valeriya V. Kurilenko y Svetlana P. Ermakova. "Fucoidan Sulfatases from Marine Bacterium Wenyingzhuangia fucanilytica CZ1127T". Biomolecules 8, n.º 4 (21 de septiembre de 2018): 98. http://dx.doi.org/10.3390/biom8040098.
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Fucoidans belong to a structurally heterogeneous class of sulfated polysaccharides isolated from brown algae. They have a wide spectrum of biological activities. The complex structures of these polysaccharides hinder structure-activity relationships determination. Fucoidan sulfatases can make useful tools for the determination of the fine chemical structure of fucoidans. In this study, identification and preparation of two recombinant sulfatases able to catalyze the cleavage of sulfate groups from fragments of fucoidan molecules is described for the first time. Two genes of sulfatases swf1 and swf4 of the marine bacterium Wenyingzhuangia fucanilytica CZ1127T were cloned and the proteins were produced in Escherichia coli cells. Sulfatases SWF1 and SWF4 are assigned to S1_17 and S1_25 subfamilies of formylglycine-dependent enzymes of S1 family (SulfAtlas). Some molecular and biochemical characteristics of recombinant fucoidan sulfatases have been studied. Detailed specificity and catalytic features of sulfatases were determined using various sulfated fucooligosaccharides. Structures of products produced by SWF1 and SWF4 were established by nuclear magnetic resonance (NMR) spectroscopy. Based on the obtained data, the enzymes are classified as fucoidan exo-2O-sulfatase (SWF1) and fucoidan exo-3O-sulfatase (SWF4). In addition, we demonstrated the sequential action of sulfatases on 2,3-di-O-sulfated fucooligosacchrides, which indicates an exolitic degradation pathway of fucoidan by a marine bacterium W. fucanilytica CZ1127T.
Tesis sobre el tema "Fucoidan"
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Ghebouli, Radouane. "Intérêt de la vectorisation du t-PA au thrombus : exemple du Fucoidan aminé". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC213/document.
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Les accidents vasculaires cérébraux (AVC) ischémiques, l’infarctus du myocarde (IDM) et l’embolie pulmonaire (EP) sont la première cause de mortalité et de morbidité dans le monde. Leur prise en charge est limitée à la recanalisation des vaisseaux occlus par le thrombus. La thrombolyse intraveineuse par le rt-PA (l’activateur tissulaire du plasminogène recombinant) est le seul traitement médicamenteux utilisé dans ces situations d’urgences vasculaires. En dépit de ces bénéfices, cette thérapie s’entrave de plusieurs effets délétères principalement d’un risque d’hémorragie cérébrale. Augmenter le rendement fibrinolytique du rt-PA via sa vectorisation sans augmenter ses effets délétères serait d’un grand intérêt. Le Fucoidane, un polysaccharide anionique extrait principalement des algues brunes, ayant une affinité de l’ordre du nanomolaire à la P-sélectine, a démontré un ciblage spécifique du thrombus in vivo. Dans notre travail, nous avons développé une molécule bipolaire associant le Fucoidane comme vecteur au thrombus, aminé par des lysines en N–terminales pour lier le rt-PA exogène. Le potentiel de vectorisation du t-PA par le Fucoidane aminé ainsi que la preuve du concept ont été validé par notre travail. Nous avons montré sur des modèles de thrombi in vitro une accélération de lyse des thrombi, et in vivo une augmentation de l’efficacité thrombolytique du t-PA, couplé au Fucoidan aminé, par injection périphériqueAcute ischemic stroke (AIS), acute myocardial infarction (AMI), and pulmonary embolism (PE) are the main cause of mortality and morbidity worldwide. Thrombolysis by intravenous injection (IV) of recombinant tissue plasminogen activator (rt-PA) remains the most common non-interventional treatment to recanalize vessels occluded. However, Its use is limited by significant drawbacks, including bleeding complications. Recent studies showed that Fucoidan (sulfated polysaccharides extracted from brown algae) target in vivo intraluminal thrombus.In this study, we have developed a bipolar construct associating Fucoidan, able to target the thrombus, and a NH2 exposing lysine platform able to bind to t-PA. We hypothesize that this construct was able to vectorize t-PA to the thrombus, would increase its fibrinolytic efficacy and avoid its deleterious effects. In vitro assays, t-PA complexed to amino Fucoidan has shown its over thrombolytic superiority as compared to tPA alone. In vivo mesenteric, arterial and deep vena cava thrombosis and thrombolysis, vascular reperfusion was significantly increased in mice treated with amio Fucoidan complexed to t-PA as compared in mice treated by t-PA alone. This data demonstate that amino Fucoidan is an excellent vector of t-PA to the thrombus
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Oliveira, Ruth Medeiros de. "Avalia??o das atividades farmacol?gicas de fucoidans obtidos do extrato bruto de fucoidan comercial de Fucus vesiculosus". Universidade Federal do Rio Grande do Norte, 2015. http://repositorio.ufrn.br/handle/123456789/21156.
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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Fucoidan ? um termo usado para definir polissacar?deos pertencentes ao grupo das heterofucanas que apresentam na sua constitui??o menos de 90% de L-fucose. Uma exce??o a esta regra ? o fucoidan obtido da alga Fucus vesiculosus. Este fucoidan ? comercializado pela empresa SIGMA-ALDRICH Co. e tem sido utilizado em v?rias pesquisas para avalia??o de suas atividades farmacol?gicas. No entanto, este produto n?o ? uma mol?cula pura, sendo na verdade uma mistura de diferentes fucoidans. Neste trabalho foram obtidos, a partir de precipita??o com acetona, quatro fucoidans a partir do extrato bruto do fucoidan de F. vesiculosus comercializado pela SIGMA-ALDRICH Co. para avalia??o de suas atividades anticoagulante, antioxidante, antiadipog?nica, imunomodulat?ria e antiurol?tica. Na atividade anticoagulante, avaliada pelo teste de TTPa, destacaram-se os fucoidans F0.9, F1.1 e F2.0 que induziram um aumento de oito vezes no tempo de coagula??o, quando comparado ao controle, quando uma massa de 10 ?g foi aplicada. J? para o teste de TP, apenas o fucoidan F0.9 foi capaz de aumentar o tempo de coagula??o em compara??o ao controle. Na capacidade antioxidante total (CAT), a atividade do fucoidan F2.0 correspondeu a aproximadamente 400 equivalentes de ?cido asc?rbico, enquanto que o fucoidan F0.5 foi o menos efetivo, com atividade referente a aproximadamente 38 equivalentes. Com rela??o ao efeito sobre a adipog?nese de c?lulas pr?-adipocit?rias (3T3-L1), foi observado que alguns fucoidans causaram uma redu??o da adipog?nese, como foi o caso de F1.1 e F2.0 e este efeito foi associado ? redu??o na express?o das prote?nas reguladoras C/EBP?, C/EBP? e PPAR?. Por outro lado, os fucoidans F0.5 e F0.9 induziram a adipog?nese pelo aumento da express?o desses reguladores proteicos. Al?m disso, o fucoidan F2.0 foi capaz de induzir a hidr?lise de triglicer?deos presentes no interior dos adip?citos. O efeito imunomodulador foi avaliado e foi observado que a presen?a dos fucoidans F0.5, F1.1 e F2.0 reduziram significativamente a produ??o de ?xido n?trico por macr?fagos ativados com LPS, com destaque para o fucoidan F2.0 que, na concentra??o de 100 ?g/mL, conseguiu reduzir, em aproximadamente, 55% o efeito causado pelo LPS. J? com rela??o ao efeito dos fucoidans sobre a forma??o de cristais de oxalato de c?lcio, foi observado que o fucoidan F0.5 interferiu, mais efetivamente, sobre a agrega??o desses cristais e tal efeito n?o foi significativamente diferente com rela??o ao efeito causado pelo extrato bruto. Al?m disso, o fucoidan F0.5 promoveu a forma??o apenas de cristais do tipo dihidratados (COD), enquanto que os fucoidans F1.1 e F2.0 n?o interferiram significativamente sobre a forma??o dos cristais, quando comparados ao controle. Os resultados obtidos neste trabalho indicam que o extrato bruto do fucoidan de Fucus vesiculosus comercializado ?, na verdade, uma mistura de diferentes fucoidans que, por sua vez, possuem composi??es qu?micas diferentes al?m de possu?rem atividades farmacol?gicas diferenciadas e que o uso desses fucoidans ? indicado de acordo com a atividade farmacol?gica a ser avaliada.
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 ?g 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/EBP?, C/EBP? and PPAR?. 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 ?g/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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Tengdelius, Mattias. "Fucoidan-Mimetic Glycopolymers : Synthesis and Biomedical Applications". Doctoral thesis, Linköpings universitet, Kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-131093.
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The marine polysaccharide fucoidan has demonstrated several interesting biological properties, for instance being antiviral, anticoagulant, anti-inflammatory, anticancer, and platelet activating. Many of these properties are desirable for various biomedical applications. Yet, there are few reports on fucoidan being used in such applications. The reasons for this are primarily the heterogeneity and low structural reproducibility of fucoidan. This thesis describes the synthesis of polymers with pendant saccharides bearing the key structural features of fucoidan. These glycopolymers were synthesized via different radical polymerization techniques yielding polymers of different chain lengths and dispersity. These glycopolymers showed antiviral and platelet activating properties similar to those of natural fucoidan, thus making them fucoidan-mimetic glycopolymers. However, compared to fucoidan from natural sources, the fucoidan-mimetic glycopolymers had homogeneous and reproducible structures making them suitable for biomedical applications. Further studies demonstrated that platelet activation, caused by these glycopolymers, showed dose-response curves almost identical to fucoidan. The platelet activation was induced via intracellular signaling and caused platelet surface changes similar to those of fucoidan. Fucoidan-mimetic glycopolymers can therefore be used as unique biomolecular tools for studying the molecular and cellular responses of human platelets. Fucoidan-mimetic glycopolymers generally assert their antiviral activity by blocking viral entry to host cells, thus inhibiting spreading of the viral infection but not acting virucidal, i.e. not killing the viruses. Introduction of hydrophobic groups to the polymer’s chain ends improved the antiviral properties significantly and is an important step towards yielding glycopolymers with virucidal properties. The fucoidan-mimetic glycopolymers were also applied as capping agents when synthesizing gold nanoparticles. These fucoidan-mimetic glycopolymer coated gold nanoparticles showed improved colloidal stability compared to uncapped gold nanoparticles. Furthermore, the nanoparticles also demonstrated selective cytotoxicity against a human colon cancer cell line over fibroblast cells.
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Janodien, Fatima. "Proteome signature of breast cancer cells treated with fucoidan". University of the Western Cape, 2016. http://hdl.handle.net/11394/5315.
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>Magister Scientiae - MScBreast cancer is responsible for a large portion of cancer-related deaths. Worldwide, incidence is increasing. Routinely-used treatments for breast cancer are invasive and are associated with a range of side-effects which may affect quality of life. Fucoidan, a marine bioactive compound, found primarily in brown seaweed, has various medicinal qualities. Among its bioactivities studied, it has potent anticancer activity. Despite numerous studies, the mechanism of action of fucoidan on cancer cells remains unclear. This project aims to shed light on the mechanism of action of fucoidan by studying its effect on the MCF7 breast cancer cell proteome. The IC50 obtained for fucoidan treated MCF7 cells was 0.2 mg/ml. Decrease in expression of XIAP and phosphorylation of ERK1/2 was observed, indicating a decrease in inhibition of apoptosis and increased sensitivity to apoptosis, respectively. Literature reports activation of several caspases, including caspase-3, in various cell lines after to fucoidan treatment. Taken together, with data from the current study it can be said that fucoidan treatment led to cell death by apoptosis. SILAC analysis identified over 2000 proteins with more than 1700 at 95% confidence. STRING analysis of enriched proteins revealed 19 cell death related proteins. However, SILAC results were ambiguous with regards to differential protein regulation and should be repeated with lower electrospray ionization flow rates, pairwise and single sample runs, and validation with Western blot analysis of various apoptosis related proteins and biochemical assays.
National Research Foundation
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January, Grant Garren. "Bioprospecting for bioactive polysaccharides from marine algae endemic to South Africa". University of the Western Cape, 2016. http://hdl.handle.net/11394/5322.
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>Magister Scientiae - MScFucoidan is a marine-derived sulphated polysaccharide with bioactive properties ideal for the food, chemical and pharmaceutical industries. The polysaccharide consists largely of L-fucose, has a highly heterogeneous structure and is of diverse origin. Fucoidan was extracted from Ecklonia maxima, Laminaria pallida and Splachnidium rugosum and the effect of different extraction methods on fucoidan heterogeneity was assessed. Extraction methods employed hot water, hydrochloric acid or calcium chloride salt. Fucoidan yield and purity were determined by various colorimetric assays. Highest fucoidan yield was obtained with the hot water extraction method as seen by highest L-fucose content. Splachnidium rugosum extracts contained ~5 times more L-fucose than Ecklonia maxima and Laminaria pallida extracts. The salt extraction method yielded extracts free of contaminants, however L-fucose content in all extracts was >20 times lower. Acid extraction yielded highest levels of uronic acid contamination and liberated sulphate from the fucoidan polysaccharide. The fucose-to-sulphate ratio for Ecklonia maxima was approximately 1:5, whilst the ratios for Splachnidium rugosum and Laminaria pallida were approximately 1:1 and 1:2, respectively. The acid and salt extraction methods removed all traces of protein contaminants, while the hot water method retained very low levels of protein. The extraction method used to isolate fucoidan was a determining factor in yield and purity. Chemical compositional analyses of hot water extracts were assessed by gas chromatography mass spectroscopy. Splachnidium rugosum and Laminaria pallida extracts consisted largely of L-fucose, while Ecklonia maxima fucoidan was characterized with high glucose abundance. Crude hot water and acid extracts from Splachnidium rugosum tissue were fractionated and purified by (anionic) ion exchange chromatography as bioactivity has been correlated to lower molecular weight forms. In water extracts, ion exchange chromatography resulted in close to 90% decrease in L-fucose, sulphate and uronic acid, while protein content increased by 57%. Similar results were reported for acid extracts; however protein content did not change significantly. These results show that method of extraction may affect the composition of fucoidan post-purification. Hot water extraction is recommended due to higher fucoidan yield, as reflected by L-fucose content, and higher sulphate-to-fucose ratio. High protein content after ion exchange chromatography was however of concern. Since mucilage in Splachnidium rugosum thallus was free of protein, fucoidan was precipitated from mucilage with ethanol. Fucoidan yield of mucilage was >15-fold higher than content in purified hot water extracts with a sulphate-to-fucose ratio of ~1:1. The average molecular weight of native fucoidan in mucilage was estimated at 2367 kDa. The polysaccharide was hydrolysed by gamma-irradiation levels of 10-50 kGy to fractions ranging between 60 and 15.5 kDa. Hot water crude fucoidan extracts from Ecklonia maxima, Laminaria pallida, and Splachnidium rugosum were assessed for anti-oxidant activity by measuring the ability to scavenge free radicals and the capacity to reduce copper ions with 2,2-Diphenyl-1-picrylhydrazyl and Cupric Reducing Anti-oxidant Capacity assays, respectively. Ecklonia maxima crude fucoidan displayed highest anti-oxidant activity and capacity, having the potential to scavenge reactive oxygen species as well as the capacity to reduce copper to less toxic forms in mammalian systems. Splachnidium rugosum showed weakest anti-oxidant activity and lowest reducing capacity. The anti-cancer activity of crude and purified hot water Splachnidium rugosum extracts, as well as non-irradiated (native) and gamma-irradiated fucoidan, and commercially procured fucoidan were assessed for anti-cancer activity against MCF-7 breast cancer cells. Splachnidium rugosum crude and purified fucoidan displayed a half maximal inhibitory concentration of 0.7 mg/mL and 0.029 mg/mL, respectively. Low cytotoxicity of crude and purified Splachnidium rugosum fucoidan against non-cancerous breast epithelial cell line MCF-12A was observed, as seen by half maximal inhibitory concentration values of 2 mg/mL and 0.663 mg/mL, respectively. The cancer specific selectivity of purified Splachnidium rugosum fucoidan was therefore much higher as reflected by 10-fold higher selectivity index than that of crude fucoidan. Native and low molecular weight gamma-irradiated fucoidan also showed bioactive properties including anti-cancer activity as seen by the reduction of cell proliferation in vitro, whereas crude fucoidan showed the ability to scavenge free radicals, and the capacity to reduce copper ions.
National Research Foundation (NRF)
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Dias, Ana Carla da Silva Carvalho. "Efeito protetor da fucoidina, um inibidor de P e L-selectina, na resposta inflamatÃria sistÃmica e distÃrbios de motilidade gastrintestinal na pancreatite aguda experimental". Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10774.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorIntroduÃÃo e objetivos: Os neutrÃfilos desempenham importante papel na pancreatite aguda grave. InfiltraÃÃo de neutrÃfilos no pÃncreas à um processo complexo, coordenado por molÃculas de adesÃo especÃficas, tais como a P-selectina. Fucoidina à um polissacarÃdeo sulfatado que bloqueia a funÃÃo da L-e P-selectinas. No presente estudo avaliamos se o tratamento com fucoidina poderia impedir a infiltraÃÃo de neutrÃfilos e, assim, reverter a inflamaÃÃo sistÃmica e dismotilidades gastrintestinais associadas à pancreatite aguda grave. MÃtodos: A pancreatite aguda foi induzida em camundongos Swiss pela infusÃo retrÃgrada de Ãcido taurolitocÃlico (3,0%) (TLC-S) no ducto pancreÃtico ou por injeÃÃes intraperitoneais de ceruleÃna (50 Âg/kg/h). Os grupos experimentais receberam fucoidina (25 mg/kg, iv) antes da induÃÃo da pancreatite, e os grupos de controle receberam apenas soluÃÃo salina. ApÃs 24 horas, os nÃveis sÃricos de amilase, lipase, IL-1β, TNF-α, nitrito e de malondialdeÃdo (MDA) pancreÃtico foram medidos. AlÃm disso, a atividade de mieloperoxidase (MPO) (pulmÃo, pÃncreas, estÃmago e jejuno) e avaliaÃÃo histolÃgica (pÃncreas) foram determinadas. O esvaziamento gÃstrico e trÃnsito gastrintestinal foram medidos pelo mÃtodo de centro geomÃtrico. A contratilidade gastrintestinal in vitro foi registrada atravÃs de transdutores de forÃa conectados a sistema computadorizado de aquisiÃÃo de dados. Carbacol (0,01 ÂM - 30 ÂM), KCl 60 mM e estimulaÃÃo elÃctrica (0,5-8,0 Hz; 1ms, 40 V), foram aplicados sobre o fundo gÃstrico e jejuno dos animais 24 horas apÃs a pancreatite induzida por TLC-S. Resultados: Os nÃveis de MDA pancreÃtico, amilase, lipase, nitrito, TNF-α e IL-1β sÃricos, bem como MPO pancreÃtica e pulmonar estavam aumentados tanto no modelo de pancreatite aguda induzida por TLCS quanto no modelo ceruleÃna quando comparado aos grupos controle correspondentes. Fucoidina reduziu significativamente os nÃveis aumentados de amilase, lipase, MPO pancreÃtica e pulmonar, MDA, TNF-α, IL-1β e nitrito em ambos os modelos de pancreatite aguda. As mudanÃas histolÃgicas observadas no pÃncreas em ambos os modelos foram significativamente atenuadas pela fucoidina. O modelo de pancreatite aguda induzida por TLC-S induziu retardo no esvaziamento gÃstrico e trÃnsito gastrointestinal, aumento de MPO no estÃmago e no jejuno, alÃm de hipercontratilidade de jejuno in vitro. Fucoidina reverteu significativamente os distÃrbios gastrintestinais in vivo e in vitro e os nÃveis aumentados de MPO gÃstrica e jejunal induzidos pela injeÃÃo de TLC-S. ConclusÃo: Fucoidina reduziu a gravidade da pancreatite aguda experimental atravÃs da diminuiÃÃo da infiltraÃÃo de neutrÃfilos, inflamaÃÃo sistÃmica e dismotilidades gastrintestinais, sugerindo que a modulaÃÃo das selectinas, pode constituir uma abordagem terapÃutica promissora para pancreatite aguda.
Background & Aims: Neutrophils play a critical role in severe acute pancreatitis. Tissue infiltration of neutrophils in the pancreas is a multistep process, coordinated by specific adhesion molecules, such as P-selectin. Fucoidin is a sulphated fucosylated polysaccharide that binds to and blocks the function of L- and P-selectins, and the present study has evaluated whether fucoidin treatment could prevent neutrophil infiltration, and thereby reverse the systemic inflammation and gastrointestinal dysmotility associated with severe acute pancreatitis. Methods: Acute pancreatitis was induced in Swiss mice either by the retrograde infusion of taurolithocholic acid (3.0%) (TLC-S) into the pancreatic duct or by intraperitoneal injections of cerulein (50 Âg/kg/h). The experimental groups received fucoidan (25 mg/kg, i.v.) before pancreatitis induction whist control groups received only saline. After 24 hours, pancreatic malondialdehyde (MDA), serum amylase, lipase, IL-1β, TNF- and nitrite were measured. In addition, myeloperoxidase (MPO) activity (lung, pancreas, stomach and jejunum) and histological assessment (pancreas) were determined. Gastric emptying and gastrointestinal transit (using the geometric center method) were also measured. Gastrointestinal contractility in vitro was recorded through force transducers coupled to a computerized data acquisition system, carbachol (0,01 ÂM â 30 ÂM), KCl 60mM and electrical field stimulation (0.5-8.0 Hz; 1ms; 40 V), was applied on gastric fundus and jejunum of mice 24 hours after TLC-S induced pancreatitis. Results: Pancreatic MDA, serum amylase, lipase, nitrite, TNF- and IL-1β, pancreatic and lung MPO, were increased in both TLCS- and cerulein acute pancreatitis compared with respective control groups. Fucoidan significantly decreased the augmented levels of amylase, lipase, pancreatic and lung MPO, MDA, TNF-, IL-1β and nitrite in both acute pancreatitis models. Pancreas histological changes observed in both models were significantly attenuated by fucoidan. The acute pancreatitis model induced by TLC-S caused delayed gastric emptying and gastrointestinal transit, incresead gastric and jejunum MPO, and jejunum hypercontractility in vitro. Fucoidan significantly reversed the gastrointestinal disorders in vivo and in vitro and augmented levels of gastric and jejunum MPO induced by TLC-S. Conclusion: Fucoidan reduced the severity of acute pancreatitis in mice by decreasing neutrophil infiltration, systemic inflammation and gastrointestinal dysmotility, suggesting that modulation of selectins may constitute a promising therapeutic approach for acute pancreatitis.
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Xavier, Caroline Addison Carvalho. "Efeito do Fucoidam de Fucus vesiculosus em um modelo experimental de artrite reumat?ide". Universidade Federal do Rio Grande do Norte, 2005. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12624.
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Rheumatoid arthritis (RA) is systemic auto imune disorder. It is caracterized by chronic inflammation of joints leading to progressive erosion of cartilage and bone. We investigated the effect of the administration of fucoidan, sulfated polysaccharides, from algae Fucus vesiculosus in the acute (6h) in zymosan-induced arthritis (AZy). Wistar rats (180-230 g) were used for all groups experimental. Non-treated animals received just intraarticular injection of 1 mg the zymosan, control group received intraarticular injection of 50 ?L the saline, groups received either fucoidan of Fucus vesiculosus (15, 30, 50 or 70 mg/Kg) or parecoxib (1 mg/Kg) 1 hour after injection of zymosan. After 6 h, the articular exudates were collected for evaluation of the cell influx and nitrite (Griess reaction) release. The sinovial membranes and articular cartilages were excised for histopathological analysis and by determination of the glycosaminoglycan (GAG), respectively. ZyA led to increased NO and cell influx into the joints. Therapeutic administration of the fucoidan or parecoxib did significantly inhibited the cell influx and the synovitis, as compared to non-treated rats (p<0,05), though being able to reduced NO release. Representative agarose gel electrophoresis of the GAGs, the content of condroitin-sulphate was observed during the process. These findings suggest that the fucoidan from Fucus vesiculosus has potential anti-inflammatory activity
A artrite reumat?ide (AR) ? uma doen?a auto-imune sist?mica, caracterizada por inflama??o cr?nica das articula??es, resultando em progressiva eros?o cartilaginosa e ?ssea. Neste trabalho foi investigado o efeito da administra??o do fucoidam, polissacar?deos sulfatados, da alga marinha Fucus vesiculosus na fase aguda (6h) da artrite induzida por zymosan (AZy). Ratos Wistar (180-230 g) foram utilizados para todos os grupos experimentais. Animais n?o tratados receberam apenas 1 mg de zymosan intraarticular (i.a), o grupo controle recebeu 50 ?L de solu??o salina intraarticular (i.a.), os outros grupos receberam fucoidam de Fucus vesiculosus (15, 30, 50 ou 70 mg/Kg,) ou parecoxib (1 mg/Kg), por via intraperitoneal (i.p.) 1 hora ap?s a inje??o de zymosan (i.a.). Ap?s 6 h, o exsudato articular foi coletado para an?lises do influxo celular e libera??o de nitrito (reagente de Griess). As membranas sinoviais e as cartilagens articulares foram retiradas para an?lises histopatol?gicas e para a determina??o dos glicosaminoglicanos, respectivamente. A AZy caracterizou-se por libera??o aumentada de NO e influxo de c?lulas inflamat?rias, nas juntas. A administra??o terap?utica do fucoidam ou parecoxib inibiu (p<0,05) o influxo celular, a libera??o de ?xido n?trico e a sinovite, comparado ao grupo n?o tratado. Por eletroforese em gel de agarose e tamp?o PDA 0,05M pH9,0 foi observado bandas com migra??es semelhantes ao condroitim sulfato (CS). Estes resultados sugerem que o fucoidam de Fucus vesiculosus tem um potencial anti-inflamat?rio
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Maina, Mwangi Henry. "Structural investigation of the natural products composition of selected South African seaweeds". University of the Western Cape, 2014. http://hdl.handle.net/11394/4339.
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Philosophiae Doctor - PhDRecently, a great deal of interest has developed towards the isolation of bioactive compounds from marine sources due to their numerous health benefits. Furthermore, marine algae are valuable sources of structurally diverse metabolites with scientifically proven therapeutic claims. The cell walls are rich in sulfated polysaccharides such as fucoidans in brown algae, carrageenans in red algae and ulvans in green algae. These sulfated polysaccharides exhibit many beneficial biological activities such as anticoagulant, antiviral, antioxidative, anticancer and immunomodulating activities. They have great potential for further development as products in cosmeceutical, pharmaceutical and nutraceutical areas. Although the mechanism of action is still not clear, their biological activities could be mainly attributed to their major secondary metabolites namely; phlorotannins, terpenoids and fucoidans. There was use of comprehensive chromatographic separations and a full analysis of isolates using one or other of the spectroscopic techniques. Antioxidant and cytotoxicity tests were perfomed in details for Ecklonia maxima. Furthermore, structural and electronic features of the phlorotannins were compared in an attempt to provide an explanation for the differences in their radical scavenging properties. In this regard, two main radical scavenging mechanisms, hydrogen atom transfer (HAT) and electron transfer (ET), were assessed in order to determine the preferred mode of radical scavenging. Fully relaxed geometry optimizations of the neutral and the radical species were performed utilizing DFT/B3LYP and DFT/UB3LYP methods respectively. In further studies, the structural and functional properties of sulfated polysaccharides from the three brown and one red seaweeds were investigated. This was through detailed analysis of chemical composition of crude and purified polysaccharides using PMP - derivatization of hydrolysed sugars, anion exchange, molecular weight determination, ion chromatography , FT-IR, NMR to methylation analysis. The work reports isolation and characterization of compounds from four algae: Ecklonia maxima, phlorotannin derivatives, namely phloroglucinol (22), eckol (23), 7-phloroeckol (24), 2-phloroeckol (25) and a sterol, 24-ethylidine cholesterol (26); Splachinidium rugosum, 24-ethylidine cholesterol ( 26), 1, 3-Dicapryloyl-2-oleoylglycerol (27), E-3,7,11,15-tetramethylhexa dec-2-en-1-ol (phytol) (2 8); Macrocystis angustifolia, 24-ethylidine cholesterol (26); a red seaweed Aeodes orbitosa, and E -3, 7, 11, 15-tetramethylhexad ec-2-en-1-ol (28) and 17-(5-Ethyl-6-methylheptan-2-yl)-10,13-dimethyl-2,3,4,7, 8,9,11,12,14,15,16,17-dodecahydro-1 H-cyclopenta[a]phenanthren-3-ol (β-sitosterol) (29). Experimental findings and theoretical predictions of phlorotannins indicated that the radical scavenging activities followed the order 22< 23 < 25 < 24. Theoretical studies further indicated the ET mechanism is more significant than the HAT mechanism due to the high BDE values. Their polysaccharide structures were tentatively shown to have a backbone of (1-3) and (1-4) linkages with sulfate groups at O-2 and O-2, 3 positions. The only red algae studied contained, 2-O-methyl-D-galactose with (1-3) and (1-4)-glycosidic linkages possessing sulfate groups at positions 2 and 6.
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C?mara, Rafael Barros Gomes da. "Atividades anticoagulante e antioxidante de extratos brutos ricos em polissacar?deos sulfatados das macroalgas marinhas marrons Canistrocarpus cervicornis, Dictyota mertensii e Dictyopteris delicatula e de Heterofucanas de Canistrocarpus cervicornis". Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12571.
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Previous issue date: 2010-10-28Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
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
No presente estudo, extratos brutos ricos em polissacar?deos sulfatados foram obtidos a partir de tr?s esp?cies de Dictyotales (uma ordem de macroalgas marrons): Canistrocarpus cervicornis, Dictyota mertensii e Dictyopteris delicatula, e suas atividades anticoagulante e antioxidante foram avaliadas. Todos os extratos apresentaram atividade anticoagulante frente ao ensaio de aPTT, mas n?o sobre o ensaio de PT. Os extratos tamb?m exibiram atividade antioxidante total, capacidade em sequestrar radicais super?xido e propriedade de quelar ferro. O extrato obtido a partir de C. cervicornis apresentou os melhores resultados e foi escolhido para ter seus polissacar?deos sulfatados fracionados e subsequentemente analisados. Deste modo, seis fra??es (CC-0.3, CC-0.5, CC-0.7, CC-1.0, CC-1.2 e CC-2.0) foram obtidas por prote?lise seguida de precipita??o sequencial com acetona. Eletroforese em gel de agarose corada com azul de toluidina comprovou a presen?a de polissacar?deos sulfatados em todas as fra??es. As an?lises qu?micas mostraram que todas as fra??es apresentam heterofucanas constitu?das principalmente por fucose, galactose, ?cido glucur?nico e sulfato. Nenhuma fra??o alterou o PT. Entretanto todas as fra??es foram capazes de dobrar o aPTT de uma maneira dose dependente. As fra??es, CC-0.3, CC-0.5, CC-0.7 e CC-1.0, precisaram de apenas 0,100 mg/mL para dobrar o tempo de coagula??o, concentra??o que ? apenas 1,25 vezes maior do que aquela utilizada com Clexane? (heparina de baixo peso molecular) para se obter o mesmo efeito. As heterofucanas apresentaram apreci?vel capacidade antioxidante total, baixa capacidade em sequestrar radicais hidroxila e uma boa efici?ncia em sequestrar radicais super?xido (exceto CC-1.0). CC-1.2 mostrou uma capacidade de sequestrar 43,1 % dos radicais super?xido. Este resultado foi maior do que o apresentado pela mesma concentra??o de ?cido g?lico (41,8 %), um antioxidante conhecido. Al?m disso, as heterofucanas mostraram uma excelente atividade em quelar ferro (exceto CC-0.3). CC-0.5, CC-0.7 e CC-1.0 apresentaram as maiores atividades com 47,0 % de quela??o f?rrica, um resultado 2 vezes menor do que o exibido pela mesma concentra??o de EDTA. Estes resultados indicaram claramente os efeitos ben?ficos de heterofucanas extra?das de C. cervicornis como potenciais agentes anticoagulante e antioxidante. Entretanto, passos adicionais de purifica??o, estudos estruturais, al?m de experimentos in vivo, s?o necess?rios para que estas fucanas possam vir a ser utilizadas como agentes terap?uticos
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Kilian, Linda [Verfasser] y Siegmund [Akademischer Betreuer] Lang. "Molekularbiologische und mikrobielle Studien zur enzymatischen Spaltung von Fucoidan / Linda Kilian ; Betreuer: Siegmund Lang". Braunschweig : Technische Universität Braunschweig, 2012. http://d-nb.info/1175823716/34.
Texto completoLibros sobre el tema "Fucoidan"
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Cancer cells with fucoidan seaweed commits suicide (Korean edition). unknown, 2008.
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Green, Olivia. Anti-cancer Nutrients : Fucoidan & AHCC: What you need to know about Fucoidan & AHCC. Understand their benefits and side effects for cancer treatment. Createspace Independent Publishing Platform, 2018.
Buscar texto completoCapítulos de libros sobre el tema "Fucoidan"
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Olatunji, Ololade. "Fucoidan". En Springer Series on Polymer and Composite Materials, 95–120. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-34709-3_5.
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Sinurat, Ellya, Dina Fransiska, Nurhayati y Hari Eko Irianto. "Fucoidan". En Marine Biochemistry, 285–304. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003303916-12.
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Sezer, Ali Demir y Erdal Cevher. "Fucoidan: A Versatile Biopolymer for Biomedical Applications". En Active Implants and Scaffolds for Tissue Regeneration, 377–406. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/8415_2011_67.
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Vimala, Thangaraj, Thinanoor Venugopal Poonguzhali y Muthu Sakthivel. "Potential Health Benefits of Fucoidan: An Update". En Phycobiotechnology, 141–85. Series statement: Innovations in biotechnology; volume 3: Apple Academic Press, 2020. http://dx.doi.org/10.1201/9781003019510-7.
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Mussatto, Solange I. "Microwave-Assisted Extraction of Fucoidan from Marine Algae". En Methods in Molecular Biology, 151–57. New York, NY: Springer New York, 2015. http://dx.doi.org/10.1007/978-1-4939-2684-8_9.
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Danilova, Irina G., Saied A. Aboushanab, Ksenia V. Sokolova, Gokare A. Ravishankar, Ambati Ranga Rao y Elena G. Kovaleva. "Anti-Diabetic Properties of Fucoidan from Different Fucus Species". En Sustainable Global Resources of Seaweeds Volume 2, 579–95. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92174-3_31.
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Anastyuk, Stanislav D., Natalia M. Shevchenko y Vladimir I. Gorbach. "Fucoidan Analysis by Tandem MALDI-TOF and ESI Mass Spectrometry". En Methods in Molecular Biology, 299–312. New York, NY: Springer New York, 2015. http://dx.doi.org/10.1007/978-1-4939-2684-8_19.
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Matsuda, Yoshiko, Kiichiro Teruya, Sakiko Matsuda, Ayumi Nakano, Takuya Nishimoto, Masashi Ueno, Akitomo Niho et al. "Anti-Cancer Effects of Enzyme-Digested Fucoidan Extract from Seaweed Mozuku". En Basic and Applied Aspects, 295–300. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-3892-0_49.
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Lakmal, H. H. Chaminda, Ji-Hyeok Lee y You-Jin Jeon. "Enzyme-Assisted Extraction of a Marine Algal Polysaccharide, Fucoidan and Bioactivities". En Polysaccharides, 1–11. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-03751-6_46-1.
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Lakmal, H. H. Chaminda, Ji-Hyeok Lee y You-Jin Jeon. "Enzyme-Assisted Extraction of a Marine Algal Polysaccharide, Fucoidan and Bioactivities". En Polysaccharides, 1065–77. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16298-0_46.
Texto completoActas de conferencias sobre el tema "Fucoidan"
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WANG, Xue-lian y Yan ZHAO. "Molecular Actions of Marine Bioactive Compound Fucoidan". En 2nd International Conference on Biomedical and Biological Engineering 2017 (BBE 2017). Paris, France: Atlantis Press, 2017. http://dx.doi.org/10.2991/bbe-17.2017.38.
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Shu-Ping Zhang, Xu Wang, Shu-Hua Chen y Xiang Zhao. "Study on the desalination of crude extract of Fucoidan". En 5th International Conference on Responsive Manufacturing - Green Manufacturing (ICRM 2010). IET, 2010. http://dx.doi.org/10.1049/cp.2010.0473.
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Veerichetty, Veerabhuvaneshwari y Ashra Sindhikkaa Mohammed Rafi. "Comparative antioxidant capacity of fucoidan batches extracted from Sargassum species". En THE 8TH ANNUAL INTERNATIONAL SEMINAR ON TRENDS IN SCIENCE AND SCIENCE EDUCATION (AISTSSE) 2021. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0108910.
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Wu, Szu-yuan. "Abstract 4151: Fucoidan reduced radiation-induced fibrosis and secondary primary cancers". En Proceedings: AACR Annual Meeting 2018; April 14-18, 2018; Chicago, IL. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1538-7445.am2018-4151.
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Supanto, K. M., E. Saepudin y E. Sinurat. "Modification of fucoidan from Sargassum filipendula by sulfate enrichment and its antioxidant activity". En PROCEEDINGS OF THE 4TH INTERNATIONAL SYMPOSIUM ON CURRENT PROGRESS IN MATHEMATICS AND SCIENCES (ISCPMS2018). AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5132491.
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Delma, Caroline R., Guru Prasad Srinivasan, Nune Raviprakash, Sunil K. Manna, Somasundaram T. Somasundaram y Natarajan Aravindan. "Abstract 5508: Fucoidan fromTurbinaria conoidesattenuates pancreatic cancer progession by regulating p53 - NFκB crosstalk". En Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA. American Association for Cancer Research, 2015. http://dx.doi.org/10.1158/1538-7445.am2015-5508.
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Liao, Yu-Hsiang, Ming-You Shie, Yi-Wen Chen, Wan-Ni Huang y Yu-Fang Shen. "Development of A Three-dimensional Sponge Dressing Containing Fucoidan for Skin Damage Repair". En 2022 IEEE 22nd International Conference on Bioinformatics and Bioengineering (BIBE). IEEE, 2022. http://dx.doi.org/10.1109/bibe55377.2022.00047.
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Sopelkina, K. I., I. V. Geide y I. S. Selezneva. "Search for ways to obtain fucoidan from brown algae Fucus Vesiculosus and Laminariae Thalli". En THE VII INTERNATIONAL YOUNG RESEARCHERS’ CONFERENCE – PHYSICS, TECHNOLOGY, INNOVATIONS (PTI-2020). AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0032834.
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Potoroko, I., A. Paymulina, D. Uskova, N. Popova y M. Velyamov. "Improvement of Saccharomyces cerevisiae and Lactococcus delbrueckii ssp. bulgaricus bioactivity by sonochemically microstructured fucoidan". En INTERNATIONAL CONFERENCE ON FOOD SCIENCE AND BIOTECHNOLOGY (FSAB 2021). AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0068773.
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Khalafu, Sharifah Habibah Syed, Wan Aida Wan Mustapha, Seng Joe Lim y Mohamad Yusof Maskat. "The effect of deodorization on volatile compositions of fucoidan extracted from brown seaweed (Sargassum sp.)". En THE 2016 UKM FST POSTGRADUATE COLLOQUIUM: Proceedings of the Universiti Kebangsaan Malaysia, Faculty of Science and Technology 2016 Postgraduate Colloquium. Author(s), 2016. http://dx.doi.org/10.1063/1.4966781.
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