Tesis: "Fucoidan"

1

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.

Texto completo

Resumen

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 périphérique
Acute 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

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

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.

Texto completo

Resumen

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-09T23:35:50Z No. of bitstreams: 1 RuthMedeirosDeOliveira_TESE.pdf: 4171784 bytes, checksum: 9097e00661c5b8a82a6f4a4f71850657 (MD5)
Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-15T22:18:44Z (GMT) No. of bitstreams: 1 RuthMedeirosDeOliveira_TESE.pdf: 4171784 bytes, checksum: 9097e00661c5b8a82a6f4a4f71850657 (MD5)
Made available in DSpace on 2016-08-15T22:18:44Z (GMT). No. of bitstreams: 1 RuthMedeirosDeOliveira_TESE.pdf: 4171784 bytes, checksum: 9097e00661c5b8a82a6f4a4f71850657 (MD5) Previous issue date: 2015-12-18
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.

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

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.

Texto completo

Resumen

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.

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Janodien, Fatima. "Proteome signature of breast cancer cells treated with fucoidan". University of the Western Cape, 2016. http://hdl.handle.net/11394/5315.

Texto completo

Resumen

>Magister Scientiae - MSc
Breast 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

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

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.

Texto completo

Resumen

>Magister Scientiae - MSc
Fucoidan 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)

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

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.

Texto completo

Resumen

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
IntroduÃÃo e objetivos: Os neutrÃfilos desempenham importante papel na pancreatite aguda grave. InfiltraÃÃo de neutrÃfilos no pÃncreas Ã um processo complexo, coordenado por molÃculas de adesÃo especÃficas, tais como a P-selectina. Fucoidina Ã 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 Ã 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.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

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.

Texto completo

Resumen

Made available in DSpace on 2014-12-17T14:03:43Z (GMT). No. of bitstreams: 1 CarolineACX.pdf: 623551 bytes, checksum: 6aed4455120c14dc04af31815ec90ea1 (MD5) Previous issue date: 2005-10-11
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
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

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

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.

Texto completo

Resumen

Philosophiae Doctor - PhD
Recently, 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.

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

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.

Texto completo

Resumen

Made available in DSpace on 2014-12-17T14:03:35Z (GMT). No. of bitstreams: 1 RafaelBGC_DISSERT.pdf: 2123374 bytes, checksum: 0195cd61affe048d50e8378ceba77a87 (MD5) Previous issue date: 2010-10-28
Coordena??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

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

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 completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Magalhaes, Kaline Dantas. "Atividade anticoagulante, antioxidante e antitumoral de heterofucanas da alga Dictyopteris delicatula (Lamouroux, 1809)". Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13382.

Texto completo

Resumen

Made available in DSpace on 2014-12-17T14:13:58Z (GMT). No. of bitstreams: 1 KalineDM_DISSERT.pdf: 984274 bytes, checksum: 8150a2011f0eac140bc8113ffa4bc1ea (MD5) Previous issue date: 2011-12-02
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula (Lamouroux, 1809) and their anticoagulant, antioxidant and antitumor activities were evaluated. All fractions showed anticoagulant activity on aPTT assay, but not on PT assay. Fractions also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. Thus, six fractions (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) we obtained by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. Any fractions changed the PT. However, all fractions were able on double the aPPT on a dose-dependent manner. The heterofucans F0.7v and F1.0v showed low anticoagulant activity while F1.5v presented the most prominent anticoagulant activity .When compared to Clexane?, a low molecular weight heparin, at same concentration F1.5v presented similar anticoagulant activity. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (~45%), whereas fucans F1.3v (0.5 mg/mL) showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress
No presente estudo, seis popula??es de polissacar?deos sulfatados foram obtidas a partir da alga Dictyopteris delicatula (Lamouroux, 1809) e suas atividades anticoagulante, antioxidante e antitumoral avaliadas. Deste modo, as seis fra??es (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) foram obtidas por prote?lise seguida por fracionamento de acetona e gel filtra??o molecular Sephadex G-100. Todas as fra??es apresentaram atividade anticoagulante frente ao ensaio de aPTT, mas n?o sobre o ensaio de PT. As heterofucanas exibiram atividade antioxidante total, capacidade em sequestrar radicais super?xido e propriedade de quelar ferro. As an?lises qu?micas demonstraram que todos os polissacar?deos cont?m heterofucanas composta principalmente por fucose, xilose, glicose, galactose, ?cido ur?nico, e sulfato. Nenhuma das fra??es alterou o PT. Entretanto, todas as fra??es foram capazes de dobrar o aPTT de uma maneira dose dependente. As heterofucanas F0.7v e F1.0v demonstraram baixa atividade anticoagulante, enquanto a F1.5v apresentou a maior atividade anticoagulante e quando comparada com Clexane?, uma heparina de baixo peso molecular, em mesma concentra??o, apresentou antividade anticoagulante semelhante. As fucanas F0.5v e F0.7v a 1,0 mg/mL mostraram alta atividade de quela??o ferica (~ 45%), enquanto a fucana F1.3v (0,5 mg/mL) mostrou consider?vel potencial redutor, cerca de 53,2% da atividade da vitamina C. A melhor atividade antitumoral foi encontrada nas fucanas F1.3v e F0.7v. No entanto, a atividade F1.3v foi muito superior a F0,7v, quase 100% de inibi??o da prolifera??o de c?lulas HeLa (c?lula de c?ncer de colo de ?tero). Estas fucanas foram selecionadas para novos estudos sobre caracteriza??o estrutural, bem como em experimentos in vivo, que j? est?o em andamento
2020-01-01

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Nobre, Leonardo Thiago Duarte Barreto. "Fucana ativa via das Map quinases e inibe a prolifera??o de c?lulas de ov?rio de hamster chin?s (CHO)". Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12583.

Texto completo

Resumen

Made available in DSpace on 2014-12-17T14:03:37Z (GMT). No. of bitstreams: 1 LeonardoTDBN_DISSERT_parcial.pdf: 2023324 bytes, checksum: af543040ab580eb729ea0ba7ac05cd5a (MD5) Previous issue date: 2011-07-08
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
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 schr?ederi. 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.
Fucana ? um termo utilizado para denominar polissacar?deos sulfatados ricos em L-Fucose. As fucanas t?m sido estudadas devido suas atividades farmacol?gicas: antitromb?tica, antiproliferativa e antioxidante. N?s extra?mos tr?s fra??es de fucanas da alga Spatoglossum schr?ederi. Essas fucanas, denominadas de Fuc B 1, Fuc B 1.5 e Fuc B 2, apresentam uma composi??o muito similar como demonstrado pela eletroforese em gel de agarose, e conte?do de a??car e sulfato. O efeito antiproliferativo foi determinado pelas metodologias de MTT e BrdU em c?lulas CHO. O efeito na inibi??o da prolifera??o das tr?s fra??es foi de cerca de 40%. Assim, procedemos somente com a Fuc B 2 devido seu maior rendimento. N?o houve indica??o de apoptose usando a marca??o com anexina V-FITC/ Iodeto de Prop?deo. Identificamos uma parada na fase G1 do ciclo celular. Os ensaios de western blotting mostraram que PKC, pFAK e pERK 1/2 s?o ativadas quando as c?lulas s?o tratadas com Fuc B. O tratamento com o inibidor de MAPK PD98059 aboliu o efeito da fucana. Esses efeitos indicam que a fucana age via ERK para inibir a prolifera??o das c?lulas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Abudabbus, Aisha Ibrahim. "Effects of Fucoidan and Chemotherapeutic agent combinations on Malignant and Non-Malignant breast cell lines". University of the Western Cape, 2017. http://hdl.handle.net/11394/6107.

Texto completo

Resumen

Philosophiae Doctor - PhD (Medical BioScience)
Breast cancer is currently one of the most common malignancies in women. Fucoidan (FUC) is a natural polysaccharide with anticancer properties. Despite a number of in vitro and in vivo studies reporting the efficacy of fucoidan in treating various cancers, few studies have measured the efficacy of fucoidan in combination with cancer drugs. Drugs like cisplatin, doxorubicin and taxol are important in breast cancer treatment. However, in recent years, supplements have gained importance in its treatment. Fucoidan, a sulfated polysaccharide mainly found in brown algae and seaweed, is a new candidate for breast cancer therapy because of its antitumour activity. This study was aimed at determining the cytotoxic, apoptotic and cell cycle distribution effects of fucoidan and its synergistic and/or antagonistic effects in combination with cisplatin, doxorubicin and taxol in the breast cancer cell line, MCF-7, relative to the normal MCF-12A non-malignant breast epithelial cell line.

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Kim, Kyung-Tae. "Seasonal variation of seaweed components and novel biological function of fucoidan extracted from brown algae in Quebec". Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/28833/28833.pdf.

Texto completo

Resumen

Fucus vesiculosus et Ascophyllum nodosum sont des algues brunes comestibles et abondantes au Québec. Cependant, elles ont été négligées en raison de leur valeur potentielle inconnue et de la période de récolte limitée. Afin de valider leur utilité, la composition chimique de ces algues et l’activité inhibitrice des enzymes digestives de l'amidon par les fucoïdanes extraits de ces deux espèces d'algues ont été étudiés en fonction de la saison. Les composants principaux des algues sont dans l’ordre: les polysaccharides> minéraux> protéines> fucoïdane> lipides>> composés phénoliques, et leur quantité est très variable selon la période de récolte. F. vesiculosus contenait une plus grande quantité de protéines et de minéraux, alors que A. nodosum avait relativement plus de polysaccharides. Par conséquent, F. vesiculosus serait plus avantageux comme source d’éléments nutritifs. L’algue A. nodosum récoltée en Juillet a permis d’obtenir le fucoïdane ayant la pureté la plus élevée et le meilleur rendement. Les fucoïdanes extraits des deux espèces d’algues ont inhibé l’activité de l’α-glucosidase alors que seul celui extrait d’A. nodosum a pu, de plus, inhiber l’α-amylase. Le fucoïdane d’A. nodosum était un inhibiteur plus puissant que le fucoïdane de F. vesiculosus pour l’α-glucosidase avec des IC50 variant de 0,013 ~ 0,047 mg/ml, tout comme pour l’α-amylase avec des IC50 de 0,12 ~ 4,62 mg/mL selon le mois. Pour comprendre les facteurs clés expliquant les différences d’inhibition d’α-amylase entre les fucoïdane d’A. nodosum et F. vesiculosus, certaines caractéristiques structurales ont été analysées et comparées à du galactofucoidane qui a servi de contrôle. A partir des résultats obtenus, il est confirmé que la masse moléculaire plus faible (637 kDa) du fucoïdane d’A. nodosum et la présence de sulfates sont liées à son activité inhibitrice. Nous avons émis l’hypothèse que les faibles masses moléculaires permettent d’exposer facilement les groupements sulfate qui peuvent agir sur l’α-amylase par interaction électrostatique, et donc d'inhiber son activité. En conclusion, les algues brunes du Québec présentent un potentiel d’utilisation important pour leur valeur nutritionnelle et leurs composés bioactifs. Le fucoïdane a montré une activité d'inhibition des enzymes digestives de l'amidon (α-amylase et α-glucosidase) et cette activité est différente selon les espèces d'algues et la période de récolte. Une meilleure compréhension du mécanisme inhibiteur par le fucoïdane peut être utile afin de développer un ingrédient fonctionnel permettant de prévenir le diabète de Type-2.
Fucus vesiculosus and Ascophyllum nodosum are edible brown seaweed and abundantly available in Quebec. However, they have been neglected because of their unknown value and technical limitation in harvest. In order to validate their usefulness, chemical composition in seaweeds and starch digestive enzyme inhibition activity by fucoidan extracted from two seaweed species were investigated with different seasons. The major components in both seaweeds were in order: polysaccharide > minerals > protein > fucoidan > lipid > phenol, and their quantity was quite variable depending on harvesting timing. F. vesiculosus contained larger amount of proteins and minerals, while A. nodosum had relatively more polysaccharides. Therefore, F. vesiculosus are advantageous as a nutritional source. Especially, from A. nodosum harvested in July, a fucoidan having higher purity and better yield was obtained. Fucoidans from two seaweeds species inhibited α-glucosidase activity while, only fucoidan from A. nodosum could inhibit α-amylase activity. A. nodosum fucoidan was a more potent inhibitor than F. vesiculosus fucoidan for α-glucosidase with IC50 of 0.013 ~ 0.047 mg/mL, and for α-amylase with IC50 of 0.12 ~ 4.62 mg/mL depending on harvest month. To understand the key factors explaining the difference in α-amylase inhibition between A. nodosum fucoidan and F. vesiculosus fucoidan, structural characteristic was analyzed and compared with galactofucoidan as a control. From the obtained results, it is confirmed that smaller molecular weight (637 kDa) of A. nodosum fucoidan and the presence of sulfates are related to its inhibitory activity. It is proposed that small molecular weight permits to expose easily sulfate groups for interaction with α-amylase throughout electrostatic interactions, and therefore inhibiting its activity. In conclusion, brown seaweeds in Quebec have a considerable importance for nutrition and bioactive products. Fucoidan shows the inhibition activity for starch digestive enzymes (α-amylase and α-glucosidase) and its activity is different depending on seaweed species and harvesting period. Further understanding of the inhibitory mechanism by fucoidan can be useful to develop a functional ingredient to help preventing for Type-2 diabetes.

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Vásquez, Cruzado Fabrizio Marcelo. "Estudio sobre las propiedades inmunomoduladoras y antitumorales del fucoidan de algas pardas en tratamiento combinado con quimioterapia convencional". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2021. https://hdl.handle.net/20.500.12672/17177.

Texto completo

Resumen

El cáncer es considerado un grave problema de salud pública debido a sus altas tasas de morbilidad y mortalidad alrededor del mundo. Los tratamientos más comunes que el paciente recibe para superar la enfermedad son la quimioterapia y la radioterapia. Sin embargo, tienen limitaciones como la quimiotoxicidad y resistencia al tratamiento, problema por el cual se está en la búsqueda de compuestos naturales de baja toxicidad que tengan potencial en las terapias anticancerígenas. El fucoidan es un polisacárido sulfatado encontrado en las paredes celulares de las algas pardas, exhibiendo propiedades bioactivas como inmunomodulador y antitumoral. El objetivo de este trabajo es realizar una revisión sistemática sobre el uso del fucoidan como inmunomodulador y antitumoral en combinación con quimioterápicos convencionales. Se seleccionaron resúmenes, artículos de alto impacto y tesis de distintas plataformas de búsqueda y bases de datos, elaborando tablas que describen los efectos del fucoidan en combinación con los fármacos. Los resultados demostraron que el fucoidan actúa de manera sinérgica con fármacos antineoplásicos en modelos in vitro, in vivo y en estudios preclínicos en pacientes con cáncer, potenciando la actividad inmunomoduladora, antitumoral, reduciendo la quimiotoxicidad y aumentando la tasa de supervivencia, por lo que el fucoidan sería un adyuvante potencial para el tratamiento de diversos tipos de cáncer.
Perú. Universidad Nacional Mayor de San Marcos. Vicerrectorado de Investigación y Posgrado. Programa de Promoción de Trabajo de Investigación para obtener el grado académico de bachiller. B20100220a

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Rios, Matos Dora Luisa. "Producción de citoquinas de respuesta inmune celular en ratones inmunizados y tratados con fucoidan de Lessonia trabeculata (Phaeophyceae, laminariales)". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2020. https://hdl.handle.net/20.500.12672/11736.

Texto completo

Resumen

El fucoidan es un polisacárido extraído de algas pardas y ha sido ampliamente estudiado por sus propiedades anticoagulantes, antivirales, antiinflamatorias, antioxidantes, antitumorales, antiangiogénicas e inmunomoduladoras, que varían de acuerdo a la especie. Lessonia trabeculata es un alga parda del litoral peruano que se emplea en la industria alimentaria; sin embargo, tiene otros usos potenciales que deben ser investigados. El desarrollo de nuevos productos con actividad biológica a partir de estas algas requiere de evaluaciones in vitro e in vivo. El objetivo fue evaluar la producción de citoquinas de respuesta inmune celular: TNF-α, TNF-β, IFN-γ e IL-2, la producción de especies reactivas de oxígeno (ERO) y óxido nítrico (NO) en ratones inmunizados con glóbulos rojos de carnero (GRC) y tratados con diferentes concentraciones del extracto liofilizado rico en fucoidan de Lessonia trabeculata, empleándose como control fucoidan de Fucus vesiculosus. Los ratones fueron tratados durante 14 días por vía oral, para evaluar la respuesta inmune primaria (RIP), y durante 28 días, para la respuesta inmune secundaria (RIS). Las ERO se evaluaron mediante el ensayo de reducción de nitroazul de tetrazolio, y el NO por la reacción de Griess. La expresión génica y la presencia de citoquinas séricas se determinaron mediante PCR convencional y ELISA de tipo sándwich, respectivamente. Los resultados obtenidos demuestran que el extracto liofilizado rico en fucoidan de Lessonia trabeculata no influye en la producción de ERO ni NO, incrementa la expresión de TNF-α y la concentración en suero de TNF-α, IFN-γ e IL-2 e inhibe la expresión de TNF-β en RIP, promueve la expresión de TNF-β e IL-2, inhibe la expresión de TNF-α y reduce la concentración en suero de IL-2 en RIS. Se concluye que el extracto liofilizado rico en fucoidan de Lessonia trabeculata estimula la inmunidad celular en la respuesta primaria y secundaria, sin embargo, es necesario complementar estos resultados con posteriores investigaciones.
Perú. Ministerio de la Producción. Programa Nacional de Innovación para la Competitividad y Productividad (Innóvate Perú)
Universidad Nacional Mayor de San Marcos (Lima). Vicerrectorado de Investigación y Posgrado
Tesis

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Sapharikas, Elène. "Stratégies de thérapie pro-angiogénique de l’artériopathie oblitérante des membres inférieurs". Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05S004.

Texto completo

Resumen

L’artériopathie oblitérante des membres inférieurs conduit progressivement au rétrécissement des artères qui assurent la vascularisation des membres inférieurs. Il en résulte une ischémie des tissus irrigués par ces artères et à terme, en cas d’occlusion artérielle, une ischémie critique conduisant à une amputation du membre. De nouvelles stratégies de thérapie cellulaire basées sur l’injection de cellules progénitrices capables d’induire une angiogenèse thérapeutique se sont développées ces dernières années. Cependant le faible taux d’incorporation des cellules transplantées dans le tissu ischémique limite le développement de ces nouvelles approches. Dans ce contexte, mon travail de thèse a consisté à étudier deux approches thérapeutiques distinctes pouvant améliorer les thérapies pro-angiogènes. La première étude porte sur le fucoïdane, polysaccharide sulfaté d’origine naturelle, antithrombotique favorisant la formation de nouveaux vaisseaux sanguins dans le modèle murin d’ischémie du membre inférieur. Nous avons montré qu’il induisait le recrutement de monocytes en améliorant leur adhésion à l’endothélium activé en condition dynamique, ainsi que leur adhésion à la matrice et leur transmigration in vitro. Cette action est médiée par l’activation des voies de signalisation ERK et p38 et la sécrétion de métalloprotéinases 9. De plus, le fucoïdane entraine une polarisation des macrophages de type pro-angiogènes in vitro. Il augmente leur recrutement dans le muscle ischémié permettant de réduire ainsi la phase inflammatoire post-ischémique, la nécrose et de favoriser le processus de cicatrisation. La deuxième étude porte sur le rôle des neuropilines (NRP), co-récepteurs du VEGF (facteur de croissance pro-angiogène) exprimés à la surface des ECFC, afin de comprendre leur implication au niveau moléculaire dans le mécanisme d’action pro-angiogène des ECFCs et optimiser l’efficacité de la thérapie cellulaire. A l’aide du système d’extinction par ARN interférent, nous avons découvert un mécanisme de compensation jamais étudié auparavant puisque l’inhibition de NRP1 entraine une augmentation de celle de NRP2 et une diminution de la prolifération et de la migration des ECFCs. En revanche, l’extinction de NRP2 n’a pas d’effet sur l’expression de NRP1, mais induit une augmentation de l’adhésion des ECFCs à la matrice extracellulaire associée à une augmentation de la phosphorylation des ERK1/2
Vascular diseases such as Peripheral Arterial Disease may evolve towards critical limb ischemia, requiring revascularization or amputation. New strategies of cell therapy based on the injection of progenitor cells able to induce therapeutic angiogenesis have been recently developed. However the low level of incorporation of transplanted cells in the ischemic tissue limits the development of these new approaches. In this context, my thesis was to study two different therapeutic approaches that can improve the pro-angiogenic therapies. The first focuses on fucoidan, a marine sulphated polysaccharide with antithrombotic properties. We have previously shown promising angiogenic properties of fucoidan in vivo. We found that fucoidan increases monocyte recruitment and improves their adhesion to activated endothelium under dynamic condition. It also increases in vitro transmigration. This action is mediated by the activation of ERK and p38 signaling pathways and metalloproteinase 9 secretion. Further, fucoidan can lead macrophage polarization to the pro-angiogenic type in vitro. It increases macrophage recruitment in ischemic muscle that could reduce post-ischemic inflammatory phase and necrosis leading to healing process. The second study focuses on the role of neuropilin (NRP), co-receptors of VEGF (pro-angiogenic growth factor). The aim of this part was to understand their involvement in the pro-angiogenic properties of ECFC at molecular level and optimize the efficiency of cell therapy. Using siRNA, we found a compensation mechanism never studied before. The NRP1 inhibition leads to an increase in the NRP2 expression and a decrease of ECFC proliferation and migration. The NRP2 silencing has no impact on NRP1, but induces ECFC adhesion to the extracellular matrix correlated with an increased level of ERK1 / 2 phosphorylation

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Jorge, Ricardo Ferreira. "Isolation and structural characterization of fucoidans from the brown algae Fucus vesiculosus". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15669.

Texto completo

Resumen

Mestrado em Biotecnologia - Biotecnologia Molecular
agricultural, pharmaceutical, cosmetic or bioenergy applications. They contain bioactive compounds, namely, polysaccharides Fucoidan. These polysaccharides are mainly constituted by fucose residues and sulfate esters, and have been reported to possess a broad variety of bioactivities, such as anticoagulant, anti-thrombotic, anti-inflammatory, anti-tumor, antiviral and antioxidant. In this work, the fucoidans from brown seaweed Fucus vesiculosus from “Ria de Aveiro” were isolated and characterized in order to add value to this natural resource of the region. The polysaccharides from the algae were extracted with hot water and fractioned by ethanol precipitation and calcium chloride salts. They were further purified by using anion-exchange chromatography, allowing to separate the neutral polysaccharides (laminaranas) from those negatively charged (sulfated fucoidans and alginate). The purified polysaccharides showed high content of fucose (41 mol%) and sulfates (50 mol%), having also galactose residues (6 mol%), which confirm the presence of only sulfated fucoidans. Glycosidic linkages analysis show the presence of high amounts of terminal fucose (25%) and (1→3,4)-Fuc (26%), allowing to infer that the fucoidans were highly branched. These fucoidans are composed also by (1→2)-Fuc (14%) and (1→3)-Fuc linkages (10-16%). In this work it was also tested an alternative extraction technology, the microwave hydrodiffusion and gravity system, where it was possible to extract sugars, although in low yields. However, this methodology allowed to extract polysaccharides, constituted mainly by fucose and uronic acids, as well as mannitol, without the need to add any solvent, obtaining at the end the dry alga. The current work allowed to characterize the structure of the fucoidans isolated from “Ria de Aveiro” F. vesiculosus. The presence of high content of sulfate residues and the high branch degree of the purified fucoidans allow to infer that these polysaccharides could have potential to be studied for biomedical applications, according to their biological activities.
As algas castanhas fazem parte de um grupo de organismos cuja utilização tem vindo a crescer nas áreas da alimentação, agricultura, farmacêutica, cosmética e bioenergia. Estas algas são constituídas por diversos compostos com atividades biológicas destacando-se as fucoidanas. Estas são polissacarídeos compostos maioritariamente por fucose e ésteres de sulfato, apresentando várias atividades biológicas, tais como anticoagulante, anti trombótica, anti-inflamatória, anti-tumoral, antivírica e antioxidante. Neste trabalho foram isoladas e caracterizadas as fucoidanas da alga castanha, Fucus vesiculosus, da Ria de Aveiro de forma a potenciar este recurso natural da região. Os polissacarídeos constituintes da alga foram extraídos com água quente e fracionados por precipitação em etanol e sais de cloreto de cálcio. Os polissacarídeos foram purificados utilizando uma cromatografia de troca aniónica, permitindo separar os polímeros neutros (laminaranas) dos carregados negativamente (fucoidanas sulfatadas e alginatos). Os polissacarídeos purificados eram constituídos por fucose (41 mol%) e sulfatos (50 mol%), contendo também galactose (6% mol), comprovando a presença de apenas fucoidanas sulfatadas. A análise das ligações glicosídicas, mostrou a presença de fucose terminal (25%) e (1→3,4)-Fuc (26%), demonstrando que as fucoidanas eram muito ramificadas. Outras ligações presentes são (1→2-)-Fuc (15%) e (1→3)-Fuc. Neste trabalho foi também testada uma tecnologia de extração alternativa, o sistema de micro-ondas de hidro-difusão e gravidade, onde foi possível extrair alguns açúcares, embora com rendimentos reduzidos. Esta metodologia permitiu extrair os polissacarídeos, constituídos por fucose e ácidos urónicos, e também manitol sem necessidade de adicionar qualquer solvente e permitindo obter a alga seca no final da extração. Este trabalho permitiu caracterizar estruturalmente as fucoidanas isoladas do F. vesiculosus da Ria de Aveiro. A elevada quantidade de ésteres de sulfato e o elevado grau de ramificação sugere que estes polissacarídeos têm potencial para serem estudados em relação às suas atividades biológicas para serem usados em aplicações biomédicas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Oroya, Lazo Carlos Andrés. "Estudio in vivo de la actividad moduladora del fucoidan de Lessonia trabeculata Villouta & Santelices (1986) sobre parámetros de la inmunidad innata y humoral". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/10564.

Texto completo

Resumen

Evalúa el efecto inmunomodulador del fucoidan de Lessonia trabeculata en un modelo murino. Se trataron ratones por vía oral con fucoidan de L.trabeculata y se inmunizaron con glóbulos rojos de carnero (GRC). Un grupo de ratones recibió una dosis de 5 y otro, de 10 mg/kg p.c. Se emplearon 2 grupos controles: uno fue tratado con fucoidan de Fucus vesiculosus a la dosis de 5 mg/kg p.c. y otro, con solución salina (0.9%). En los 4 grupos se evaluó tanto la respuesta inmune primaria, como la secundaria. Concluidos los tratamientos se extrajeron los macrófagos peritoneales para evaluar parámetros de la inmunidad innata; Especies reactivas de oxígeno (ERO), especies reactivas de nitrógeno (ERN) y fagocitosis; y parámetros de la inmunidad humoral: presencia de anticuerpos hemaglutinantes (IgM) y opsonizantes (IgG). Los resultados obtenidos para los citados parámetros fueron contrastados con la presencia de mRNA transcripcional para IL-4, IL-5, IL-6 e IL-10 en esplenocitos. Adicionalmente se determinó la presencia de IL-10 sérico por ELISA. Los resultados indican que el fucoidan puede aumentar la producción de ERO en la respuesta inmune primaria (RIP), no detectándose diferencias en la respuesta inmune secundaria (RIS). La producción de ERN aumentó de forma dosis dependiente en la RIP y RIS. La fagocitosis mediada por anticuerpos en la RIS aumentó significativamente solo en el grupo tratado con fucoidan de L. trabeculata con dosis 10 mg/kg p.c. También se observó que la expresión transcripcional de IL-4, IL-5, IL-6 e IL-10 por esplenocitos fue modulada y dependiente del tratamiento, dosis y tipo de respuesta inmune. En contraste, no se encontraron diferencias estadísticamente significativas entre L.trabeculata y F.vesiculosus, y dosis en la producción de hemaglutininas anti-GRC, ni en la concentración de IL-10 en suero. Se concluye que el tratamiento con fucoidan de L. trabeculata por vía oral en ratones inmunizados posee capacidad de estimular diferentes parámetros inmunes como la producción de ERO y ERN, fagocitosis mediada por anticuerpos y expresión transcripcional de IL-4, IL-5, IL-6 e IL-10.
Tesis

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Toccas, Salas Mary Luz. "Estudio del efecto del fucoidan de Lessonia trabeculata nativa (alga parda) sobre la capacidad migratoria y clonogénica de la línea celular de carcinoma mamario murino 4T1". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2020. https://hdl.handle.net/20.500.12672/13998.

Texto completo

Resumen

El fucoidan es un polisacárido sulfatado presente en las algas pardas, cuya estructura y composición varía entre las diferentes especies de algas y se ha demostrado que posee efectos anticancerígenos, entre otros. El objetivo del presente estudio fue evaluar el efecto del fucoidan de Lessonia trabeculata (FLt) sobre la capacidad migratoria y clonogénica de la línea celular de carcinoma mamario murino 4T1. Se determinó la citotoxicidad de FLt mediante el ensayo MTT; se calculó la IC50 (concentración que inhibe el 50% de la población) y el índice de selectividad (IS). Como controles de actividad se consideraron el estándar de fucoidan de Fucus vesiculosus (FFv) y el quimioterápico doxorrubicina (Dox). Las células VERO-76 fueron empleadas como control de células normales. Se realizó el ensayo de migración celular por el método de “cierre de herida” y el ensayo clonogénico considerando 3 concentraciones de FLt, seleccionadas a partir de su IC50. Los resultados muestran que el FLt redujo la viabilidad celular de 4T1, con una IC50 de 950 µg/mL, y ejerció menor toxicidad sobre VERO-76, demostrando toxicidad selectiva sobre 4T1 (IS= 3.15). El FFv ejerció menor efecto citotóxico sobre ambas líneas celulares. El FLt inhibió significativamente y de manera dosis-dependiente la migración celular y la capacidad clonogénica o formación de colonias de 4T1 en concentraciones de 700, 950 (IC50) y 1200 µg/mL respecto al control no tratado (p<0.0001) a las 12 y 24 h de exposición. Adicionalmente se consideró el tratamiento combinado [Dox + FLt] IC50, demostrándose que el FLt IC50 incrementa la efectividad de doxorrubicina sobre 4T1. Se concluye que el FLt tiene el potencial de inhibir la proliferación, migración y capacidad clonogénica de 4T1 in vitro de manera selectiva y dosis-dependiente.
Perú. Consejo Nacional de Ciencia y Tecnología. Fondo Nacional de Desarrollo Científico y Tecnológico (Fondecyt). Proyecto de Investigación Básica. N° 133-2017
Tesis

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Pan, Cheng-Hsin y 潘承昕. "The effect of molecular weight of fucoidan on genipin-crosslinked chitosan/fucoidan complex membranes". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/67321072992267313745.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

Oliveira, Ana Catarina Freitas Salazar. "Fucoidan-based strategies envisioning antitumor therapies". Doctoral thesis, 2020. http://hdl.handle.net/1822/76431.

Texto completo

Resumen

Tese de doutoramento em Engenharia de Tecidos, Medicina Regenerativa e Células Estaminais
Current cancer treatments present some drawbacks, namely unwanted side effects of chemotherapeutics, due to their toxicity over healthy tissues. Trying to overcome this impactful limitation, the use of natural compounds that may present diminished effects over non-cancer cells is of great interest. Among them, fucoidan, a sulfated polysaccharide extracted from brown algae, has been highlighted over the last years due to its interesting biological features. Since different fucoidans may present distinct antitumor behaviors, one of the main goals of this PhD work was to optimize fucoidan usage by developing more effective antitumor therapies. Accordingly, in Chapter III, different fucoidan extracts from Fucus vesiculosus were tested over human breast cancer and normal cells. Three types of biological outcomes were observed: i) toxicity to cancer and normal cells; ii) toxicity to cancer cells at lower concentrations than normal cells (an effective antitumor behavior) and iii) toxicity to normal cells at lower dosages than cancer cells (for high concentrations). These discrepant activities were attributed to differences in the sulfates position and branching of fucoidan. The anti angiogenic potential of the effective fucoidan extract (type ii) was also validated by an endothelial cell tube formation assay (in vitro) and a Chick Chorioallantoic Membrane assay (in vivo) (Chapter IV). The cytotoxic effect of the same fucoidan extract was also demonstrated to human melanoma cells (Chapter V). In a complementary approach, a skin patch to treat melanoma was developed by the immobilization of fucoidan at the surface of an electrospun nanofibrous mesh. Empowering the use of this marine-origin polymer, the fucoidan extract type iii was chosen to develop a drug delivery system for breast cancer. Gemcitabine, a chemotherapeutic drug, was successfully encapsulated into fucoidan/chitosan nanoparticles showing higher toxicity to cancer cells than to normal endothelial cells (Chapter VI). Aiming to reduce gemcitabine side-effects and to develop more precise therapies, an ErbB-2 antibody was immobilized at the surface of the previously described nanoparticles (Chapter VII). The targeting to cancer cells was confirmed in a co-culture system (increased toxicity to cancer cells) and in vivo, observing the impaired tumor growth and reduced lungs metastasis. These studies proposed fucoidan-based strategies (either extracts or systems) that should be further explored in the development of more effective antitumor therapies based in natural compounds.
Os tratamentos atualmente utilizados para o cancro apresentam algumas limitações. A utilização de compostos naturais, que poderão apresentar efeitos reduzidos sobre células não cancerígenas, constitui uma potencial alternativa. De entre os vários compostos, a fucoidana, um polissacarídeo sulfatado extraído de algas castanhas, apresenta propriedades biológicas interessantes. Uma vez que diferentes fucoidanas podem apresentar diferentes comportamentos antitumorais, um dos principais objetivos deste trabalho de doutoramento foi otimizar a utilização da fucoidana para o desenvolvimento de abordagens terapêuticas. Neste sentido, no Capítulo III, diferentes fucoidanas extraídas de Fucus vesiculosus foram testadas sobre células tumorais de mama e células normais. Três comportamentos biológicos distintos foram observados: i) toxicidade para células tumorais e normais; ii) toxicidade para células tumorais a concentrações mais baixas do que para células normais (i.e. comportamento antitumoral efetivo) e iii) toxicidade para células normais a concentrações mais baixas que células tumorais (para concentrações elevadas). A discrepância entre estes comportamentos foi atribuída a diferenças na posição dos grupos sulfato e às ramificações na cadeia polimérica. O potencial anti angiogénico do extrato antitumoral efetivo foi validado através de um ensaio de formação de vasos (in vitro) e implantação na membrana corioalantóide (in vivo) (Capítulo IV). Os efeitos citotóxicos deste extrato foram também demonstrados sobre uma linha celular de melanoma. Numa abordagem complementar, uma membrana para o tratamento do melanoma foi desenvolvida mediante imobilização da fucoidana na superfície de malhas de nanofibras produzidas por electrofiação (Capítulo V). Para potenciar o uso deste polímero de origem marinha, a fucoidana tipo iii foi utilizada no desenvolvimento de um sistema de libertação de fármaco para o tratamento do cancro da mama. Gemcitabina, um fármaco quimioterapêutico, foi eficazmente encapsulada em nanopartículas (NPs) de fucoidana/quitosano, demonstrando maior toxicidade sobre células tumorais do que sobre células endoteliais (Capítulo VI). Tendo por objetivo reduzir os efeitos secundários do fármaco e para desenvolver terapias mais precisas, um anticorpo (ErbB-2) foi imobilizado à superfície das NPs (Capítulo VII). A capacidade das NPs serem direcionadas para as células tumorais foi confirmada através de um sistema de co-cultura (maior toxicidade para as células tumorais). Ensaios in vivo, demonstraram comprometimento do crescimento dos tumores e metastização nos pulmões. Estes estudos apresentam estratégias à base de fucoidana (quer na forma de extratos quer de sistemas) tendo em vista o desenvolvimento de terapias antitumorais mais eficientes.
I would like to acknowledge all the funding that allowed me to perform all this work referred specifically in each chapter and Norte 2020, for financing my PhD scholarship “Norte-08-5369-000037”.

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Irhimeh, MR. "Clinical haemopoietic implications of fucoidan treatment". Thesis, 2008. https://eprints.utas.edu.au/12940/2/Irhimeh_Whole.pdf.

Texto completo

Resumen

Haematopoiesis is a term that describes the formation of mature cellular blood components from haemopoietic progenitor stem cells (HPC). The majority of HPC reside in the bone marrow (BM) with a small number continually escaping into the circulation then re-homing back into the BM in a process called trafficking. Stromal cells in the BM constitutively express and secrete stromal cell derived factor (SDF-1). This highly conserved chemokine binds to heparin and to CXCR4 receptor acting as a chemo-attractant for CXCR4\(^+\) cells; the system plays a role in regulating stem cell trafficking. This study examined the clinical effects of ingesting fucoidan extracted from brown macro-algae (Undaria pinnatifida) in vitro and in vivo in a series of single blinded placebo-controlled clinical trials. Fucoidans comprise sulphated long branched chains of sugar, containing large amounts of fucose and galactose. Fucoidan is biologically active and is known to modulate coagulation, inflammation, cell proliferation and adhesion, tumorigenesis and resistance to viral infection. To study its clinical value an ELISA assay based on a novel antibody was established to quantify the level of the bio-available fucoidan in human plasma after oral doses. The consequences of ingesting fucoidan on healthy volunteers were investigated in detail by studying different biological and pathological parameters including liver and kidney functions. This study established that daily ingestion of 3 g of different fucoidan extracts for 2 weeks is safe. To study the anticoagulant activity of fucoidan, haemostasis was examined closely in vitro and in vivo. Although, fucoidan is a highly potent anticoagulant in vitro there was limited activity when used orally. Fucoidan was found also to positively regulate the lipid profile by reducing cholesterol and triglyceride plasma levels. The effect of fucoidan on HSPC trafficking was tested. Ingestion of fucoidan increased the expression of CXCR4 on CD34\(^+\) cells and increased the plasma level of SDF-1 and IFN-γ. A decrease in CD4\(^+\) and CD8\(^+\)+ cells was also observed in volunteers who ingested fucoidan. When either peripheral blood or cord blood CD34+ cells were cultured in vitro in a cytokine expansion system CXCR4 on CD34\(^+\) cells was down-regulated. This study also showed that fucoidan slows down the CD34\(^+\) cell cycle and interacts and binds with different cytokines (SCF, TPO, Flt-3 and SDF-1) and presents them to cells. In conclusion, this study showed that fucoidan has several clinical effects including effects on lipids regulation, haemostasis, immune system, haematopoiesis, trafficking of HSPC and related cytokines.

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Shiu, Sin-Yun y 許馨勻. "The Effect of Molecular Weight of Fucoidan on Chitosan/Fucoidan Nanoparticles via Oral Delivery System against Colon Cancer". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/jr8cr2.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
105
Fucoidan is a complex sulfated polysaccharide that is found in brown algae. Recently, the diverse biological activities of fucoidan have been studied intensively. In particular, the antitumor activity has recently attracted considerable attention. Fucoidan has also been shown to induce a substantial reduction in viable cell numbers and apoptosis of human colon cancer HT-29 cells. Fucoidan polymers can modulate cell growth in different manners depending on their molecular weight.　However, in the stomach and small intestine may lead hydrophilic macromolecules of fucoidan cannot diffuse across the cells through the lipid-bilayer cell membranes. In this study, fucoidan was extracted from the Laminaria japonica, hydrolyzed by hydrogen peroxide and subsequently fractionated using an ultrafiltration system, which produced three fucoidan fractions with different molecular weights. To overcome the poor oral bioavailability, a pH sensitive Chitosan/Fucoidan nanoparticle (CS/F NP) was prepared to against colon cancer. The objectives of this study were to determine the physicochemical properties of these fucoidan fractions and to investigate the relationship between their molecular characteristics and promote in vitro anticancer activity with CS/F NPs. We successfully prepared three fucoidan fractions with 436 kDa, 23-128 kDa and 8 kDa, named HF, MF and LF, respectively. The results suggest that the nanoparticles composed of chitosan and fucoidan were successfully prepared based on their electrostatic interaction. The size of CS/F NPs was around 149-228 nm. The CS/F NPs reveals significant pH sensitive property and high loading efficiency as the weight ratio of chitosan to fucoidan was 3:1. According to control release studies, the encapsulated fucoidan was released from NPs under simulated intestinal pH environment (pH=7.4). In vitro studies suggested that LF inhibited the growth of HT-29 cell better with the IC50 was 245.53 μg/mL. After preparation for CS/LF NPs, the IC50 was 203.29 μg/mL. Indicating that the preparation of fucoidan nanoparticles will not affect its anticancer activity. The results of transepithelial electric resistance (TEER) of Caco-2 show that NPs effectively enhanced opening of cell tight junctions. Briefly, all the results mentioned above suggest that LF should be explored as a potential anticancer agent, and the CS/F NPs developed in this study are a promising carrier for oral delivery of fucoidan against colon cancer and improve its bioavailability.

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Lin, Shu-Yun y 林淑筠. "Determination of Ingredient Concentrations in Commercial Fucoidan Products". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/j47kgv.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
106
In this study, we investigated the general testing specifications and indicative ingredient concentrations of different fucoidan products in Taiwan market. Eleven kinds of commercially available fucoidan products were collected to measure the content of uronic acid, sulfate and total sugar, then compared with in vitro antioxidative capacities (DPPH and ABTS free Radical scavenging ability), and further analyze the cconcentrations of the fucose, index component of fucoidan by high performance liquid chromatography. The concentrations of uronic acid were between 0.15 ± 0.00~19.44 ± 0.20 g/100 g, the concentrations of sulfate were 0.21 ± 0.01~20.73 ± 0.46 g/100 g. Among them, the highest value was sample A which used Okinawa brown algae as raw material. The total sugar concentrations were between 0.06 ± 0.01~681.91 ± 16.61 mg/g, and the sample J showed the lowest level. In vitro antioxidative capacity tests, sample E was the best one for DPPH and ABTS free radical scavenging abilities. The fucose content was the highest 40.21 ± 0.33 g/100 g in sample A. This study established the relevant test specifications for different fucoidan products and the regulatory compliance of the commercially available fucoidan products.

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Hsieh, Kun-Lin y 謝坤霖. "Synthesis of vaccine nanocarrier of fucoidan hybrid biocompatible polymer". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/31272236897984459936.

Texto completo

Resumen

碩士
國立臺灣科技大學
材料科學與工程系
105
In this study, we synthesized biocompatible vaccine nanocarrier hybrid polysaccride Fucoidan. Our research including two parts: In the first part, Gelaitn was hybrided with Fucoidan by chemical crosslinking method, a mean size was observed by DLS & SEM images, which located between 200~400nm nanoparticle, crosslinking structure has been comfirmed by IR spectrum. A high loading efficiency (45%) and high stability carrier (only 10% of drug were loss during 2 weeks) was prepared, which was measured by UV-vis spectrum. Furthermore, we observed drug loading image by CLSM after stability test. In the second part, we utilized Click chemistry to combine Fucoidan and Polycaprolactone, which created Fucoidan-graft-Polycaprolactone amphiphilic polymer(FD@PCL), we comfirmed azide and alkynyl group IR signal at 2100cm-1, and then we identified Triazole ring signal around 8.0ppm of 1H NMR, under FD: PCL=1:50 synthesis condition. Moreover, we produced high stability, high drug loading efficiency carrier transforming from THF to water condition, surprisingly we discovered that size distribution approximately located at 200nm and increased while drug loading, eventually demonstrated 86% encapsulation efficiency, which maintain below 10% loss during one month, measuring by UV-vis spectrum. At last, we observed nanoparticles containing green fluorescence images by CLSM. Keywords:Gelatin、Biocompatible polymers、Fucoidan、vaccine carrier、 Chemical crosslink、Amphiphilic polymer、Polycaprolactone.

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

Lin, Xiao-Zhen y 林筱蓁. "The fabrication and characterization of fucoidan-cisplatin conjugate nanoparticles". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/99813125106989618155.

Texto completo

Resumen

碩士
國立臺灣海洋大學
生命科學暨生物科技學系
103
Fucoidan is a sulfated polysaccharide and has been demonstrated having a variety of immunomodulatory effects, such as promoting activation of T cells and enhancing anti-tumor responses, inhibit cancer cell drug efflux pump of multidrug resistance. Cisplatin is a widely used as chemotherapy drug in the treatment of human solid tumors. Thakral et al. showed that the interaction of the platinum (II) atom with the negative charge of the anion polymer could cause spontaneous folding to form a nano-conjugate. Hence, the aim of this study was to fabricate the fucoidan-cisplatin conjugate nanoparticles. The diameter of fucoidan-cisplatin conjugate nanoparticles (FuCis) was between 150 and 600 nm. Moreover, the FuCis could enhance the immune activity and reveal a better chemotherapeutic efficiencies in vitro.

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

Hou, Wen-Ping y 侯文萍. "In Vitro immunomodulatory Function of Fucoidan from Cladosiphon okamuranus". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/10436235989962664017.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
103
Fucoidan refers to a type of polysaccharide which contains substantial percentages of L-fucose and sulfate ester groups. It has many physiological activities such as anti-tumor, immunomodulatory, anti-inflammatory, anti-clotting, anti-thrombotic, anti-viral, anti-oxidation, and anti-lipemia. In this study, fucoidan isolated from Cladosiphon okamuranus investigated for its immunomodulatory potential by using in vitro assays. The glycosidase inhibitory assay showed that fucoidan has the ability to inhibit α-glucosidase and α-amylase. In vitro, fucoidan has the ability to scavenge free radicals. The immune-stimulating activity of fucoidan was elucidated by using RAW264.7, Jurkat and HB4C5 cells. The result showed that fucoidan enhanced proliferation of RAW 264.7 cells under the influence of significantly decreased the level of Nitro-Blue tetrazolium chloride (NBT), restrained the secretion of IL-6 and TNF-α, stimulated production of IL-10 and also enhanced phagocytosis activity of RAW264.7. Fucoidan also enhanced HB4C5 cell proliferation and significantly stimulated secretion of IgM and does not affect the IgG, as well as stimulated interferon-γ production of Jurkat cell. Based on these results, fucoidan has a potential to be used as a natural reagent for immune regulation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Barbosa, Ana Isabel Ferreira. "Delivery of methotrexate using fucoidan/chitosan pH sensitive nanoparticles". Master's thesis, 2017. https://hdl.handle.net/10216/106503.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Barbosa, Ana Isabel Ferreira. "Delivery of methotrexate using fucoidan/chitosan pH sensitive nanoparticles". Dissertação, 2017. https://hdl.handle.net/10216/106503.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

LAN, CHI-CHANG y 籃啟昌. "Preparation of Low-Molecular-Weight Fucoidan from Undaria pinnatifida". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/26900602907719903547.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Gonçalves, Joana Daniela Ferreira. "Development of multifunctional fucoidan-coated nanoparticles for combined cancer therapy". Master's thesis, 2018. http://hdl.handle.net/10773/25897.

Texto completo

Resumen

Magnetic nanoparticles, namely magnetite nanoparticles (NP) have been subject of research and development for application in the biomedical field, especially in magnetic hyperthermia as a therapy for cancer. NPs are often coated with various materials such as silicates and natural or synthetic polymers such as chitosan or polyethylene glycol (PEG), in order to improve biocompatibility but also to enhance their colloidal stability. Fucoidan is a polysaccharide extensively studied for biomedical applications mainly due to its biocompatibility and antitumor properties. In this work, NP of magnetite coated with fucoidan are developed and evaluated for the application in magnetic hyperthermia for cancer treatment, combining magnetic hyperthermia therapy with the antitumor properties of fucoidan. The NP are synthesized by the co-precipitation method at room temperature and, afterwards, subjected to a hydrothermal treatment with different time (1, 2, and 3 h) and temperature (150 or 200 ºC) conditions. The coating of the particles with fucoidan are performed using two methodologies: i) after their synthesis (post-synthesis coating) and ii) simultaneously with the synthesis (in situ coating). Different concentrations of fucoidan are tested in the post-synthesis coatings to evaluate their influence on the physicochemical properties and the thermal efficiency of NP. In the in situ coating syntheses, in addition to evaluating the effect of different concentrations of fucoidan, the influence of the reaction temperature on the functionalization of the NP surface are also studied. NP are characterized in terms of crystallinity and particle size, specific surface area, morphology, colloidal stability and thermal efficiency. In general, NPs synthesized and coated with fucoidan have nearly round shape morphology, and in terms of size NPs with smaller size exhibited a larger surface area. The hydrothermal treatment promoted the increase of NP crystallinity and size as a function of the time and temperature of the hydrothermal treatment. There is also an increase in polydispersity which resulted in a decrease in heating efficiency by hyperthermia. The coating with fucoidan showed to improve the colloidal stability and, consequently, the thermal efficiency due to the reduction of the interactions between the NP. For the synthesis of NP by co-precipitation and post-synthesis coated, better results were obtained in terms of stability, due to the fact that the NPs obtained in situ are smaller and have a greater tendency to agglomerate. The sample giving the best results in the heat release was the one synthesized by co-precipitation at room temperature and coated post-synthesis with a concentration of fucoidan of 2 mg/mL, presenting an Intrinsic Loss Power (ILP) of 2.6 nHm2/kg, which according to literature is considered sufficient in terms of thermal efficiency (2 to 4 nHm2/kg). In addition, this sample had an average size within the recommended range for introduction into the body (less than 20 nm) mainly for its potential application in magnetic hyperthermia. However, NP synthesized and coated simultaneously with 2 mg/mL fucoidan also showed a high thermal efficiency (1.7 nHm2/kg) and its preparation process is simpler. For all of the above described, the results obtained in this work demonstrated that NP of magnetite coated with fucoidan have potential for application in magnetic hyperthermia and may also have, as a consequence of the intrinsic characteristics of fucoidan, antitumoral properties, which allow to potentiate the cancer treatment
As nanopartículas magnéticas, nomeadamente as nanopartículas (NP) de magnetite têm sido alvo de investigação e desenvolvimento para aplicação na área biomédica, em especial na hipertermia magnética como terapia para o cancro. As NP são frequentemente revestidas com diversos materiais, tais como sílicas e polímeros naturais ou sintéticos como a quitosana ou o polietilenoglicol (PEG), visando melhorar a biocompatibilidade mas também potenciar a sua estabilidade coloidal. A fucoidana é um polissacarídeo que tem sido bastante estudado para aplicações biomédicas devido principalmente à sua biocompatibilidade e propriedades antitumorais. Neste trabalho foram desenvolvidas NP de magnetite revestidas com fucoidana e foi avaliado a seu potencial de aplicação em hipertermia magnética, com o intuito de poderem ser usadas na terapia do cancro, combinando a terapia por hipertermia magnética com as propriedades antitumorais da fucoidana. As NP foram sintetizadas pelo método de co-precipitação à temperatura ambiente e, posteriormente, sujeitas a um tratamento hidrotermal com diferentes condições de tempo (1, 2 e 3 h) e temperatura (150 ou 200 ºC). O revestimento das partículas com fucoidana foi feito utilizando duas metodologias: i) após a sua síntese (revestimento pós-síntese) e ii) simultaneamente com a síntese (revestimento in situ). No revestimento pós-síntese testaram-se diferentes concentrações de fucoidana para avaliar a sua influência nas propriedades físico-químicas e na eficiência térmica das NP. Nas sínteses com revestimento in situ para além de avaliar o efeito de diferentes concentrações de fucoidana, estudou-se ainda a influência da temperatura de reação na funcionalização da superfície das NP. As NP foram caracterizadas em termos de cristalinidade e tamanho de partícula, área superficial específica, morfologia, estabilidade coloidal e eficiência térmica. De uma forma geral, as NP sintetizadas e revestidas com fucoidana apresentaram uma morfologia quase esférica, e em termos de tamanho as NP com menor tamanho exibiram uma maior área superficial. O tratamento hidrotermal promoveu o aumento da cristalinidade e do tamanho das NP em função do aumento do tempo e temperatura do tratamento hidrotermal. Ocorreu também um aumento da polidispersividade que se traduziu numa diminuição da eficiência de aquecimento por hipertermia. O revestimento com fucoidana revelou ter influência na dispersão coloidal das NP, sendo que houve uma melhoria na estabilidade coloidal e, consequentemente, na sua eficiência térmica devido à redução das interações entre as NP. Para a sintese de NP por co-precipitação e revestidas pós–síntese, obtiveram-se os melhores resultados em termos de estabilidade, que se deverá ao facto de as NP obtidas in situ serem mais pequenas e possuirem uma maior tendência para se aglomerarem. A amostra que apresentou melhores resultados na libertação de calor foi a sintetizada por co-precipitação à temperatura ambiente e revestida pós-síntese com uma concentração de fucoidana de 2 mg/mL, apresentando um Poder de Libertação Intrínseco (ILP, do inglês Intrinsic Loss Power) de 2.6 nHm2/kg, e que de acordo com a literatura estará na faixa considerada adequada para tratamentos por hipertermia magnética (2 a 4 nHm2/kg). Adicionalmente, esta amostra possui NP com tamanho médio dentro da gama recomendável para a introdução no organismo (inferior a 20 nm) e em especial para a sua potencial aplicação em hipertermia magnética. No entanto, as NP sintetizadas e revestidas simultaneamente com 2 mg/mL de fucoidana apresentaram também uma eficiência térmica elevada (1.7 nHm2/kg ), sendo que o seu processo de preparação é mais simples. Por tudo, o descrito, os resultados obtidos neste trabalho demonstraram que as NP de magnetite revestidas com fucoidana têm potencial para a aplicação em hipertermia magnética podendo ainda ter, dadas as caracteristicas intrinsecas da fucoidana, actividade antitumoral, potenciando o tratamento do cancro
Mestrado em Materiais e Dispositivos Biomédicos

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Hu, Chun-Hao y 胡鈞皓. "Fucoidan synergizes with anticancer therapeutic agents to induce NSCLC apoptosis". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/19703282117079413128.

Texto completo

Resumen

碩士
國立陽明大學
醫學生物技術暨檢驗學系
104
Fucoidan, a sulfated polysaccharide, is extracted from brown algae, Fucus vesiculosus or Laminaria japonica. Recent studies show that fucoidan exhibits immunomodulatory and anti-cancer activities. In this study, we showed that the combination of fucoidan and therapeutic agents (include cisplatin and gefitinib) synergistically inhibited cell viability in non-small cell lung cancer. Specifically, we demonstrated that the effect of simultaneous treatment, induced apoptosis in the testing cells partially contributed from caspase 3 activation. Moreover, we found that combination of fucoidan and gefitinib induces down-regulation of Rad51 via ER stress in A549 cells, a DNA repair protein involves in lung tumorigenesis. In addition, we adopted the sequential therapy method and examined the effect of a sequential treatment of fucoidan and therapeutic agents in NSCLCs. We found that the sequential therapy (fucoidan followed by therapeutic agents) could enhanced inhibition of viability in NSCLCs. We further examine the efficacy of various molecular-weight of fucoidan, we utilized centrifugal filter tubes to separate the fractions of fucoidan. We found that low molecular-weight (50~3 KD) of fucoidan presented highly inhibition of cell viability, compared to original fucoidan. Our results suggested that small molecule of fucoidan combination with therapeutic agents might be a promising therapeutic strategy for the treatment of NSCLCs.

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Inn, Christina Wong Lee y 王莉瑩. "Immunomodulatory Function of Fucoidan Isolated from Brown Algae, Sargassum Species". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/03971866205967278318.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
101
Fucoidan refers to a type of polysaccharide which contains substantial percentages of L-fucose and sulfate ester groups, mainly derived from brown seaweed. In this study, fucoidan isolated from Sargassum specieswas investigated for its immunomodulatory potential by using in vitro and in vivo assays. In vitro, the immune-stimulating activity of fucoidan was elucidated by using RAW264.7, J774.1, Jurkat, THP-1, SI102 and HB4C5 cells. The result showed that fucoidan enhanced cell proliferation of SI102, HB4C5, THP-1 J774.1 and RAW264.7cells,significantly stimulated IgM production of SI102 and HB4C5 cells,stimulated interleukin-2 and interferon-γ production of Jurkat, enhanced phagocytosis activity of THP-1 and J774.1,enhanced Nitro-Blue tetrazolium chloride (NBT) reducing ability of RAW264.7 and J774.1 cells and inhibited excessive production of nitric oxide (NO) in lipopolysaccharide induced RAW264.7. In vivo, female BALB/c mice were orally administrated with fucoidan at the doses of 824, 1648 and 3296 mg/kg body weight for 8 weeks. In non-specific immunity experiment,the resultsdemonstrated that fucoidan significantly decreased the level of serum IgA and IgE antibodies, enhanced splenic NK cell activity and phagocytic capacity in blood monocytes,increased the secretion of interleukin-2 and decreased the secretion of interleukin-10in ConA stimulated spleen cells. In specific immunity experiment, fucoidan can increase the secretion of anti-OVA IgG,increased the secretion of interleukin-2 and decreased the secretion of interleukin-10 in OVA stimulated spleen cells.This study suggested that fucoidan isolated from Sargassum species possesses immunomodulatory properties and can be used as potential natural reagent for immune regulation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

LI, KUAN-LUN y 李貫綸. "Fucoidan Improves PM2.5-induced Myocardial Injury and Its Mechanism of Action". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3r74qs.

Texto completo

Resumen

碩士
中國文化大學
生物科技研究所
105
Suspended particulates in the atmosphere are complex particulate matter, the main source of particulate matter are haze on the surface, dust, dust storms, burning energy, minerals, second-hand smoke and volcanic eruptions. The particle diameter less than 10μm suspended particles is called PM10, can reach through the human respiratory system and accumulate in lung. In addition, suspended particles of less than 2.5μm (PM2.5), which surface area is greater and volume is less than PM10, make it easier to adsorb toxic substance, and interfere with pulmonary gas exchange. Our results indicated that: 1) PM2.5 exposure caused blood pressure increase, abnormal cardiac electrophysiologies (prolongation of QT interval and action potential platform stage), and structral remodeling (cardiac hypertrophy and fibrosis); 2) Fucoidan supplement can rescue these PM2.5-induced myocardial injury; 3) We also focused on the mechanism, expression of genes related to abnormal cardiac electrophysiologies and structral remodeling decreased after feeding fucoidan; 4) Organic and inorganic compounds in PM2.5 decreased after feeding fucoidan in mice blood and organs. According to the results from my experiments, after feeding fucoidan, high blood pressure, abnormal cardiac electrophysiologies, hypertrophy, and fibrosis caused by PM2.5 in heart can be rescued. Besides, we can design some further studies based on our PM2.5-induced high blood pressure mice.

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Reys, Lara Priscila Lopes. "Algae-origin Fucoidan on development of therapeutic approaches for Diabetes Mellitus". Doctoral thesis, 2021. http://hdl.handle.net/1822/75388.

Texto completo

Resumen

Tese de Doutoramento em Engenharia de Tecidos, Medicina Regenerativa e Células Estaminais
Diabetes mellitus (DM) is a metabolic disorder that affects 450 million people worldwide, being the sixth most common cause of death. Therefore, it is crucial to develop new therapeutic strategies and relevant models for diabetes in order to accelerate the discovery of new treatments. In this perspective, marine origin polymers represent a relatively untapped source that can be used in the creation of platforms/models to attend these needs. Algae, for instance, synthesize sulfated polysaccharides with several bioactivity properties, which added to their structural role, open new avenues in biomaterials research. The main focus of this thesis consists in the demonstration of the potential of fucoidan on the development of therapeutic approaches for diabetes mellitus treatment. Fucoidan (Fu) is an underexploited sulfated polysaccharide extracted from brown algae, which has interesting chemical and biological properties. The major obstacle for using fucoidan on polymeric devices for biomedical applications is the higher solubility in water. In order to control the solubility of fucoidan in water and increase its processability, a chemical modification was studied, a methacrylation reaction, enabling its further gelation by photocrosslinking. Quasi-spherical hydrogel particles were thus prepared, supporting the culture of human pancreatic cells (1.1B4HP), as well as the sustained delivery of insulin. Moreover, alternative methodologies based in blends of fucoidan with other natural/synthetic polymers were also explored. In particular, attention was given to agarose, with attractive gelling properties mediated by temperature. The properties of the resulting hydrogel were assessed, envisaging its use on the encapsulation of pancreatic cells (1.1B4HP cells) as a system to protect those cells from the host immune system. As pancreatic cells and islets are highly vascularized, a platform device was developed based on fibrous meshes of PCL/fucoidan using airbrush technique, with capacity to promote angiogenesis. Additionally, the anti-oxidant effect of fucoidan on beta cells was also assessed, enabling to protect those cells from oxidative stress. This fucoidan was combined with alginate, developing hydrogels capable to support the encapsulation of pancreatic cells and islets with insulin secretion responsive to glucose concentration in medium. Altogether the results obtained under the scope of this thesis gave interesting insights on the use of the new fucoidan-based structures as functional biomaterials with a potential pivotal role for diabetes treatment.
A diabetes mellitus (DM) é um distúrbio metabólico que afeta cerca de 450 milhões de pessoas em todo o mundo, sendo a sexta causa de morte. Por conseguinte, é crucial desenvolver novas estratégias/modelos terapêuticos para a diabetes levando à descoberta de novos tratamentos. Nesta perspetiva, os polímeros de origem marinha representam uma fonte relativamente inexplorada que pode ser usada na criação de plataformas/modelos para atender a essas necessidades. As algas, são um exemplo, porque sintetizam uma grande variedade de polímeros e compostos mais pequenos com várias propriedades bioativas. O foco principal desta tese consiste na demonstração do potencial do fucoidan no desenvolvimento de novas abordagens terapêuticas desenvolvidas para o tratamento da diabetes mellitus. Fucoidan (Fu) é um polissacarídeo sulfatado extraído de algas castanhas, com propriedades químicas e biológicas interessantes sendo pouco explorado. O principal obstáculo para o uso de fucoidan em dispositivos poliméricos para aplicações biomédicas é ser bastante solúvel em água. Para controlar a solubilidade do Fu na água e aumentar sua processabilidade, foi estudada uma modificação química, uma reação de metacrilação, permitindo a sua gelificação através da foto reticulação. Desta forma, foram preparadas partículas quase-esféricas, permitindo o contacto direto com células pancreáticas humanas (1.1B4HPcélulas) bem como o encapsulamento/libertação de insulina foram abordados. Além disso, metodologias alternativas baseadas em misturas do Fu com outros polímeros naturais/sintéticos também foram exploradas. A agarose teve uma atenção particular, com propriedades gelificantes atrativas dependentes da temperatura. As propriedades do hidrogel resultante foram avaliadas, antevendo a sua utilização no encapsulamento de 1.1B4HP células, para proteger essas células do sistema imunitário do hospedeiro. Como as células pancreáticas e as ilhotas Langerhans são altamente vascularizadas, foi desenvolvido um bicomposito de nanofibras PCL/Fu usando uma técnica de aerografia, esse dispositivo/plataforma tinha a capacidade de promover a angiogênese. O efeito antioxidante do fucoidan nas células beta também foi avaliado, permitindo proteger as células do stress oxidativo. Hidrogéis de fucoidan e alginato foram desenvolvidos, sendo capazes de suportar o encapsulamento das ilhotas Langerhans e promover a secreção à insulina em resposta à concentração de glucose presente no meio. Em conclusão, os resultados obtidos no âmbito desta tese foram interessantes e promissores, demonstraram a capacidade do fucoidan a ser usado como base em estruturas e mecanismos que poderão ser fundamentais para o tratamento da diabetes.
The authors especially acknowledge financial support from the Portuguese Foundation for Science FCT (Grant SFRH/BD/112139/2015), PTDC/CTM-CTM//29813/2017 with support from Fundo Social Europeu and the Programa Operacional de Potencial Humano and the research project EXPL/MAR BIO/0165/2013, from European Union with co-funding of INTERREG POCTEP projects 0330- IBEROMARE_1_P and 0687_NOVOMAR_1_P INTERREG Espanha Portugal 2014-2020 project 0302_CVMAR_I_1_P and Atlantic Area project 2011/1/164 MARMED, through ERDF as well as from Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through Structured projects NORTE-01-0145-FEDER-000021 and NORTE-01-0145-FEDER-000023.

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Lin, Mi-Hsuan y 林宓璇. "Study on the Putative Structure and the Biological Functions of Fucoidan". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/59245635011318004556.

Texto completo

Resumen

碩士
國立陽明大學
醫學生物技術暨檢驗學系
102
Fucoidan, a water-soluble and sulfated-fucans having complicated chemical structures, commonly found in brown seaweeds. Our previous studies demonstrated that fucoidan inhibits the growth of lung cancer cells and breast cancer cells. Here, we focus on the relationship between its chemical composition and in vitro anticancer activity. The major low molecular mass of fucoidan is named LMF and estimated average molecular mass about 500 Da by size-exclusion high-performance liquid chromatography (SEC-HPLC). To examine the content of fucose of LMF, we hydrolyzed the LMF via autoclave (121℃) and acetic acid. The residue was further applied the high-performance anion exchange chromatography (HPAEC) to identify the content of fucose from hydrolyzed LMF. We found that the released fucose from LMF was increased with a time-dependent manner by autoclave or a does-dependent of acetic acid in autoclave. Next, we examined the anti-cancer activity of the hydrolyzed LMF. Our previous studies demonstrated that fucoidan enhances transforming growth factor β (TGFβ) and its receptors (TGFRs) degradation in cancer cells. Here we found that LMF enhanced TGFRs degradation, whereas, the hydrolyzed LMF did not affect expression of TGFRs and decrease the viability of cancer cells. Furthermore, we examined the components of LMF by electrospray ionization mass spectrometry (ESI/MS), we found that the sulfated fucose group presented on the LMF. The results showed an essential factor in this study, the hydrolyzed LMF lost the sulfated group from fucose that the higher content of sulfated fucose group of LMF (SO3-LMF) induced the expression of LC3-II (an autophagy marker), but not hydrolyzed LMF. Taken together, we proposed that the bioactivity of fucoidan may be contributed from the content of sulfated fucose group on low molecular mass fucoidan.

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Tsai, Yi-Hsin y 蔡宜欣. "Effects of Fucoidan Supplementation on Exercise Performance and Fatigue in Mice". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/45437445183621281857.

Texto completo

Resumen

碩士
國立體育大學
運動科學研究所
103
Purpose: Laminaria Japonica Fucoidan (FD) is a well-known bioactive constituent of seaweed extract which possess a wide spectrum of activities in biological systems including anti-cancer, anti-inflammation and modulation of immune systems. However, there are few studies for the use of FD as supplement for exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of FD on ergogenic and anti-fatigue functions following physiological challenge. Method: Male ICR strain mice were randomly assigned to three groups (n = 8 per group) for treatment: (1) Vehicle control; (2) 31 mg•ml-1 of FD (FD-1X); (3) 62 mg•ml-1 of FD (FD-2X). The three groups were orally administered for 14 days. Exercise performance and anti-fatigue function were evaluated by forelimb grip strength, exhaustive swimming time, and levels of serum lactate, ammonia, glucose, and creatine kinase after 15-min swimming exercise. Result: The forelimb grip strength were significantly higher by 1.17- (P = 0.007) and 1.21-fold (P = 0.001) with FD-1X and FD-2X compared with vehicle control group. The endurance swimming time was significantly increased by 1.58- (P = 0.045) and 1.23-fold (P = 0.03) with FD-1X and FD-2X compared to vehicle treatment. Serum glucose levels, values of the FD-2X groups was significantly higher by 1.16-fold (P < 0.0001) compared than the vehicle. Only FD-2X had significant decrease by 17.7% compared with vehicle control group (P =0.0544) in serum ammonia levels. Serum lactate levels were significantly lower by 18.5% (P = 0.0032) and 22.5% (P = 0.0006), respectively, with FCD-1X and FD-2X supplementations than the vehicle treatment. Therefore, FD could be a potential agent with an anti-fatigue pharmacological effect.

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Atashrazm, F. "The anti-cancer activity of the natural product, fucoidan, in haematological malignancies". Thesis, 2016. https://eprints.utas.edu.au/23015/1/Atashrazm_whole_thesis.pdf.

Texto completo

Resumen

Leukaemia is the most common form of haematological malignancy and includes a group of diseases characterised by an uncontrolled growth of malignant haematopoietic cells. It accounts for about 33% and 3% of cancer cases in children and adults, respectively. Worldwide, approximately 350,000 new cases of leukaemia are diagnosed each year, with more than 250,000 deaths. Acute myeloid leukaemia (AML) is the most common form of acute leukaemia, accounting for around 85% of adult cases, and a leading cause of cancer death in young adults. Although chemotherapy is often effective in the treatment of AML, at least in the short term, the agents currently in use are associated with a wide range of side effects including increasing the risk of developing therapy-related cancers. Therefore, there is considerable interest in the anti-cancer potential of natural agents with lower toxicities. Fucoidan is a fucose-rich sulphated polysaccharide that exists in the cell wall matrix of brown seaweeds. This component has shown immunomodulatory and anti-tumour activities. However, the underlying mechanisms of these activities remain largely unknown. Herein, the anti-tumour activities of fucoidan were examined in in vitro and in vivo models of AML, and its activity as a potential adjunct therapy was investigated. Investigation of the effects of fucoidan on leukaemic cells (NB4; a t(15;17) positive acute promyelocytic leukaemia, KG-1a; a minimally differentiated AML, HL60; a t(15;17) negative acute promyelocytic leukaemia and K562; an acute erythroleukaemia cell line) revealed evidence that fucoidan has a selective inhibitory effect on acute promyelocytic leukaemia (APL) and not other types of AML cells, initiating apoptosis. Examination of the pathways mediating the observed apoptotic mechanisms revealed the observed effect was caspase-dependent as it was significantly attenuated by pre-treatment with a pan-caspase inhibitor. P21/WAF1/CIP1 was significantly up-regulated leading to cell cycle arrest. Fucoidan decreased the activation of ERK1/2, and down-regulated the activation of AKT through hypo-phosphorylation of Thr(308) residue but not Ser(473). The anti-tumour activity of fucoidan was supported by in-vivo evidence which demonstrated that oral doses of fucoidan significantly delayed tumour growth in the APL xenograft model in athymic Balb/c nude mice, potentially by increasing the cytolytic activity of NK cells. This is the first study to reveal the anti-tumour activity of fucoidan on leukaemia in vivo. The selective inhibitory effect of fucoidan on APL cells and its protective effect against APL development in mice may prove that fucoidan may be useful in treatment of certain types of leukaemias. APL is one of the most aggressive types of AML characterised by differentiation arrest and accumulation of abnormal promyelocytes. Current APL therapies are associated with various side effects such as hyper-leucocytosis and differentiation syndrome which occurs in a quarter of the patients and is a serious and potentially fatal complication. There is therefore interest in the possibility of reducing the incidence of these morbidities through the use of adjunctive therapies which permit lower doses of toxic therapies to be used whilst maintaining efficacy. Herein, the synergistic effects of fucoidan on current APL therapy, arsenic trioxide (ATO) and all-trans retinoic acid (ATRA), were investigated. In vitro, the effect of fucoidan combined with both therapeutic and lower doses of these drugs was examined in APL cells. Fucoidan in combination with ATO enhanced apoptosis in APL cells at both therapeutic and lower doses of ATO as indicated by an increased sub G0/G1 population, DNA fragmentation and annexin V positive apoptotic cells. Furthermore, the combination of fucoidan with low doses of ATRA and ATO significantly enhanced cell differentiation as indicated by G0/G1 arrest and increased CD11b expression. The triple combination of these agents resulted in the greatest myeloid differentiation in APL cells compared to single or double combinations. The efficacy of fucoidan as an adjuvant to the anti-leukaemic activity of ATO or ATRA was identified in vivo in athymic Balb/c nu/nu mice bearing APL. Tumour growth was monitored by measurement of tumour size and survival. When fucoidan and sub-therapeutic doses of ATO were administered in APL-bearing mice, the median survival and tumour volume doubling time significantly increased in mice treated with fucoidan alone and combined with ATO but not ATO alone compared to the control group. When fucoidan plus low dose ATRA were administered as the therapy regimen in APL-bearing mice, the median survival and tumour volume doubling time significantly increased in all treated groups compared to the control group. Moreover, the differentiation of APL cells obtained from animal’s tumour mass significantly increased in mice treated with fucoidan alone and fucoidan+ATRA but not ATRA alone compared to the control group. A further novel finding was that the differentiated APL cells derived from the excised tumour mass exhibited a down regulation of CD44 in fucoidan+ATRA treated mice. The presence of differentiated leukaemic cells with low or no expression of CD44 may be associated with decreased migration of these cells in APL. Taken together these findings provide important evidence that fucoidan may prove an effective adjuvant therapeutic agent in the treatment of selected leukaemia sub-type APL and may permit lower doses of ATO and ATRA to be employed to achieve better efficacy of treatment accompanied by lower toxicity.

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Ferreira, Sara Ataíde. "Development of fucoidan/chitosan nanoparticulate systems for protein administration through mucosal routes". Master's thesis, 2012. http://hdl.handle.net/10400.1/3668.

Texto completo

Resumen

Dissertação de mest., Engenharia Biológica , Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2012
Presently, the administration of therapeutic proteins through non-parenteral routes poses a challenge due to stability problems, mainly attributed to pH and high enzymatic content present in mucosal surfaces. Therefore, the administration of proteins through mucosal routes requires the development of suitable carriers which confer stability and protection against harsh environments of the organism and that further facilitate macromolecule permeation. Polymeric nanoparticles have been proposed as valuable systems to overcome these biological barriers, showing, in some cases, useful properties of controlled release and cellular internalization. In this context, there is also a growing tendency towards the use of natural polymers such as polysaccharides, because of their unique properties and high biocompatibility and biodegradable profile. In this work, fucoidan/chitosan (FUC/CS) nanoparticles were prepared by polyelectrolyte complexation. The aim lying in the development of these carriers is the expectation that they confer stability and protection to the biomolecules against mucosal environments, such as pH and enzymatic contents, providing a non-parenteral route for the administration of protein-based drugs. In this study, bovine albumin serum, insulin and ovalbumin were used as model proteins. Several FUC/CS mass ratios (4/1 to 1/4) were tested, resulting in nanoparticles with different sizes (338-676 nm) and zeta potentials (+41 a -49 mV). Nanoparticles FUC/CS = 1/4 and 4/1 were proposed for BSA encapsulation and variables such as order of polymer addition over each other and the polymeric solution with which the protein was mixed at first, were tested for their ability to affect the nanoparticles encapsulation efficiency. Efficiencies as high as 100% were registered (FUC/CS = 4/1) and the tested variables were found to have a stronger effect on the formulation FUC/CS = 1/4. The small sizes and high negative and positive charges displayed by the developed nanoparticles, in addition of their ability to associate macromolecules, were considered to hold potential for an application in mucosal delivery.
Presentemente, a administração de proteínas terapêuticas por vias não-parentéricas representa um desafio, devido aos problemas de estabilidade, principalmente atribuídos ao pH e conteúdo enzimáticas em superfícies mucosas. O uso de vias mucosas para a administração de proteínas exige assim, o desenvolvimento de transportadores adequados que confiram estabilidade e proteção contra ambientes agressivos encontrados no organismo e que ainda facilitam a permeação das macromoléculas. As nanopartículas poliméricas surgem então com o fim de ultrapassar estas barreiras biológicas, evidenciando ainda, em alguns casos, propriedades úteis de libertação controlada e internalização celular. Neste contexto, sugere ainda uma tendência crescente para o uso de polímeros naturais, tais como polissacáridos, devido às suas características únicas e propriedades de elevada biocompatibilidade e perfil biodegradabilidade. Neste trabalho, foram preparadas nanopartículas fucoidan/quitosano (FUC/CS) por complexação polieletrolítica. Ao desenvolver estes sistemas a expectativa é de que eles confiram estabilidade e proteção para as biomoléculas contra ambientes das mucosas, tais como o pH e elevados conteúdo enzimáticos, proporcionando uma rota não-parenteral para a administração de medicamentos à base de proteínas.Neste estudo, a albumina de soro bovino, insulina e ovalbumina foram utilizadas como proteínas modelos. Foram testados vários rácios mássicos de FUC/CS (4/1 a 1/4), que resultaram na criação de nanopartículas com diferentes tamanhos (338-676 nm) e potenciais zeta (+41 a -49 mV). As FUC/CS= 1/4 e 4/1, foram propostas para o encapsulamento da BSA, onde as variáveis tais como a ordem de adição de polímeros (protocolo A e B) e a pré-incorporação da proteína, numa das soluções poliméricas, foram testadas pela capacidade de manipular a eficiência de encapsulação (EE) das nanopartículas. Eficiências de encapsulação de 100% foram registadas (FUC/CS= 4/1) e a as variáveis testadas mostraram ter maior influência nas formulações FUC/CS=1/4. Os pequenos tamanhos e as elevadas cargas negativas e positivas das nanopartículas desenvolvidas, foram considerados adequados para a aplicação na administração de macromoléculas pela via mucosa.

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

林如欣. "Curcumin-loaded Chitosan/Fucoidan Nanoparticles via Oral Delivery System against Colon Cancer". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/23580907717701531878.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Hsu, Chin-Hao y 許晉豪. "Development and Characterization of Fucoidan-based Drug Delivery System for Cancer Therapy". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/33bd95.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

CHENG, CHIA-HO y 鄭佳和. "Use of the Health Belief Model to Examine Adults’ Fucoidan Buying Behaviors". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/dr9fk9.

Texto completo

Resumen

碩士
大仁科技大學
製藥科技研究所
106
Fucoidan, which had various biological activity, was found mainly in various species of brown seaweed and have been found in animal species, including the sea cucumber. Based on health belief model (HBM), this study aimed to explore and clarify the adults’ fucoidan buying behaviors. In this study, 379 convenient samples around Taiwan were solicited, and then data were analyzed by using descriptive statistics, dependent samples t-test, independent samples t-test, chi-square test, one-way ANOVA, and Pearson correlation with SPSS software package. The results indicated that there were only 35 respondents (9.2%) used fucoidan (multiple choice question) to supply nutrition (18 respondents, 51.3%) and to regulate the immune system (16 respondents, 45.7%). Some health belief constructs were significant different along with the demographic factors of age, residence, and health condition. There was no significant different between demographic factors and fucoidan buying behaviors. The perceived benefits and perceived barriers of health belief constructs were significant correlation with fucoidan buying behaviors. In conclusions, fucoidan had various pharmacological activity and biomedical applications, but not been very clear use until now. We suggested that the pharmacist should promote the health benefits of fucoidan to customers.

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

Zou, Ciao-Ting y 鄒喬婷. "Therapeutic Effects and Mechanisms of Fucoidan on Lung Inflammation Induced by Cigarette Smoke". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/19629731573768396485.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Wu, Cian-Yi y 吳芊逸. "Study of anti-aging on human skin by cosmetics containing small molecular fucoidan". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/44252871962884447146.

Texto completo

Resumen

碩士
弘光科技大學
化妝品科技研究所
104
According to cell experiments and animal experiments, Fucoidan has an outstanding performance in anti-inflammation, anti-tumor and anti-cancer. The experiments also pointed out Fucoidan’s hyperplasia effect on fibroblast growth. In this study, the author moved one step further to investigate small molecular Fucoidan cream’s performance in anti-aging. The author prepared three creams containing 1.00%, 3.00%, and 10.00% of small molecular Fucoidan respectively for anti-bacterial test, stability test and human subject research. According to the test redness, the subject’s derma redness was improved by 7.34% (*p<0.05) and their derma collagen structure was improved by 24.99% (*p<0.05) after they used the cream containing 1.00% of small molecular Fucoidan for 14 days, the subjects’ derma Texture was 32.10% improved (*p<0.05) and the derma pores were 37.18% improved (*p<0.05) after they used the cream containing 3.00% of small molecular Fucoidan for 7 days, the subjects’ derma collagen structure was 21.82% improved (*p<0.05) after they used the cream containing 10.00% of small molecular Fucoidan for 7 days. The author went on to investigate the effects produced by the creams containing different percentages of small molecular Fucoidan cream for users of different age groups. The experiments indicated a significant effect on derma collagen structure after users in the age group 54~60 used the cream containing 10.00% of small molecular Fucoidan, a significant effect on derma Texture after users in the age group 40~50 used the cream containing 3.00% of small molecular Fucoidan, and an increase of the derma pores after users in the age group 30~39 used the cream containing 1.00% of small molecular Fucoidan. In summary, the subject’s derma Texture, pores, Spots, elasticity, derma melanin, derma redness, derma collagen structure and pigmentation- redness had been improved significantly after they used three creams containing 1.00%, 3.00% and 10.00% of small molecular Fucoidan respectively for either 7 days or 14 days. The results proved small molecular Fucoidan cream’s effect on anti-aging.

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Chen, Shu-Jyun y 陳書竣. "5-FU-Loaded Chitosan/Fucoidan Nanoparticles for Immune and Chemotherapy in Cancer Treatment". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/m748cc.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
103
5-Fluorouracil (5-FU) is widely used in the treatment of cancer, and fucoidan can function as an adjuvant to regulate immune cells such as enhancing cell maturation and inducing immune responses. In this study, we developed 5-FU coated chitosan/fucoidan (CS/F) functional nanoparticles (NPs), which are expected as a desired treatment to combine immunotherapy with chemotherapy for cancer treatment. As the CS to F weight ratio was 5:1, the NP shows the best performance. Its diameter was 151.19 ± 9.06 nm, the zeta potential was 28.11 ± 3.01 mV and PDI was 0.22 ± 0.03. The encapsulation efficiency of 5-FU in CS/F NPs was 73.84 ± 0.83%, the loading capacity was 5.03 ± 0.05%. We observe in vitro drug release by modifying the weight ratio of polymer (CS and F) to 5-FU. As the polymer ratio increases, the release rate and amount of 5-FU are decreased; as 5-FU ratio increases, 5-FU is burst released from NPs and unable to maintain a long time. The 5-FU coated CF/S NPs have a strong toxic effect on colon carcinoma cell line HT-29 cells and can inducing HT-29 cells apoptosis. Furthermore, HT-29 cellular uptake of NPs was observed by confocal laser scanning transmission electron microscope. However, The 5-FU coated CF/S NPs showed no toxic effects on mouse fibroblasts cell line L929. In addition, the 5-FU coated CF/S NPs can induce TNF-α and GM-CSF secretion of macrophage (RAW264.7), and regulate the immune response promptly. According to the results, the 5-FU coated CF/S NPs are potential cancer therapy agents and expected as a desired treatment combining immunotherapy with chemotherapy to treat cancer.

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Hung, Chien-Fei y 洪千斐. "Investigation of extraction of fucoidan from Sargassum siliquosumand the analysis of itsmonosaccharide composition". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/34056832592793901794.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
103
Algae are widely distributed throughout global waters, and the Phaeophyta possess a polysaccharide called fucoidan which has many bioactivities. Fucoidan is water-soluble, and its main components are fucose and sulphate groups. The bioactivities of fucoidan are associated with its structure, monosaccharide composition, the content and the location of sulphate groups, and its molecular weight. The purpose of this study is to investigate the best method for extracting fucoidan from Sargassum siliquosum by the use of hot water bath extraction, microwave-assisted extraction (MAE), and ultrasonic-assisted extraction (UAE). The total sugar, reducing sugar, sulphate group content, and the functional group of the extracted fucoidan were then determined. Also, a HPLC method was established for analyzing the content of mannose, galactose, glucose, xylose and fucose in fucoidan. The optimal hydrolysis time of the sample and the optimal derivatization time for those monosaccharides were also explored. The powder of Sargassum siliquosum was extracted by using water bath extraction (80℃, 4 hours with ddH2O and 0.1 N HCl), microwave-assisted extraction (1000W, 600W and 300W for 1 and 2 minutes), and ultrasonic-assisted extraction (1400W and 800W for 30 and 60 minutes). The result showed that the best extraction solid/solvent ratio (g/mL) was 1:40. The hot water bath extraction method was found to have the highest yield: 4.21% and 6.91% were obtained by respectively using H2O and 0.1 N HCl as the extraction solvent. MAE and UAE can help to do the extraction in a shorter time while getting reasonable yields. Before doing HPLC analysis, fucoidan was hydrolyzed into monosaccharides with trifluoroacetic acid (TFA) at 120℃ for 3 hours. The hydrolyzed fucoidan is then derivatized with 1-phenyl-3-methyl-5-pyrazolone (PMP) at 70℃ for 1 hour to form monosaccharide-PMP derivatives. The separation of the five monosaccharides was performed by using a C18 column along with UV detection under 245 nm. The mobile phase used were acetonitrile: phosphate buffer (pH 6.7) = 20:80 (v/v). Large varieties of monosaccharide contents were found to relate while the extraction method of fucoidan. However, all methods showed that xylose and glucose were the least, while fucose was the highest. Sulphate content was the highest when extracted with H2O (46.03 ± 0.12 %). The analysis method established by this study was also validated. The limit of detection of mannose, glucose, galactose, xylose, and fucose of fucoidan were 0.02473, 0.21264, 0.02847, 0.02771 and 0.10256 mg/L respectively. The recoveries were among 68.8-137 %.

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Yang, Tzu-Wei y 楊子薇. "The Effect of Melatonin-Loaded Hydroxyapatite-Fucoidan Complex on Osteogenesis of Mouse Osteoblasts". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/r4x4ta.

Texto completo

Resumen

碩士
國立臺灣海洋大學
食品科學系
105
Recent reports have revealed that fucoidan has osteoconductive property, which can elevate osteoblast-related gene expressions. Another well-known candidate for bone tissue engineering applications is hydroxyapatite (HAP). The characteristics of hydroxyapatite, including size, shape, and surface charge, are the primary parameters for cellular uptake. Therefore, the aim of this study is surface modification of hydroxyapatite nanoparticles (n-HAP-N) and hydroxyapatite microparticles (μ-HAP-N) to combine with fucoidan, and then to encapsulate melatonin for evaluating its effect on differentiation of murine osteoblast-like cell line (MC3T3-E1). Hydroxyapatite nanoparticles and microparticles were 20 nm and 5 μm. in the diameter. Fourier-transform infrared spectrometer (FT-IR) and Ninhydrin test were used to confirmed the adsorption and binding of the 12-aminododecanoic acid on the HAP surfaces. Elemental analyzer calculated fucoidan grafting content of nano and micro hydroxyapatite- fucoidan complexes (HAP-N-F), which were 7 μg/mg and 15 μg/mg. X-ray diffraction (XRD) revealed that surface modifications did not change the crystal structure of HAP and successfully encapsulate melatonin. Complexes with dosage 1 mg/mL co-cultured with pre-osteoblast cells showed good biocompatibility. The results showed that added fucoidan to n-HAP-N and μ-HAP-N can enhance alkaline phosphatase (ALP), among which μ-HAP-N-F showed greater ALP activity. Melatonin-loaded hydroxyapatite-fucoidan complexes (HAP-N-F/M) can increased ALP activity and enhanced calcium deposit by releasing melatonin. In summary, melatonin-loaded hydroxyapatite-fucoidan complexes were successfully synthesized and could be a potential candidate for bone-tissue engineering applications.

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Liu, Yun-Chun y 劉芸君. "Prevention of foam cell fomation by epigallocatechin gallate/protamine/fucoidan self-assembly nanoparticles". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/a259gb.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Pountney, DC. "Performance of the black tiger prawn (Penaeus Monodon) fed fucoidan under sub-optimal conditions". Thesis, 2016. https://eprints.utas.edu.au/23097/1/Pountney_whole_thesis.pdf.

Texto completo

Resumen

The Australian wild caught prawn sector has been in a state of steady decline in terms of tonnages and value over the past decade; while the aquaculture sector for prawns has been increasing over the same period. Prawn production within the aquaculture sector accounted for 6% of the total aquaculture production value for 2012-13. The industry does experience periods of extreme environmental conditions due to the geographic location where prawns are farmed, causing financial loses. These extreme conditions include high temperatures and heavy rainfall due to onset of the monsoonal season. Environmental stress caused by acute changes in temperature and salinity impact upon the immune system and aerobic metabolism of prawns, increasing susceptibility to disease, such as Gill-Associated Virus (GAV). Immunostimulants such as fucoidan and β-glucan have shown potential to increase immune response and survival to diseases in penaeid prawns. Preliminary screening of commercially available fucoidan products were included in formulated feeds at 0.2 g.kgˉ¹ (Undaria pinnatifida [UP85 and F50], Fucus vesiculosus [FV90]) and 33 g.kgˉ¹ (Ascophyllum nodosum, MMB), and were fed to juvenile Penaeus monodon twice daily for 15 d to determine effects on growth performance, immune response and digestive gland (DG) histology. At the conclusion of the experiment the mean feed intake (FI), specific growth rate (SGR), weight gain (WG), feed efficiency ratio (FER) and survival were not different between feed treatments. Total haemocyte count (THC) and phenoloxidase activity (PO activity) did not increased in P. monodon fed fucoidan, although prawns fed the FV90 had increased granular haemocyte count (GHC) compared to prawns fed F50. DGs presented as tightly packed tubules contained within the inter-connective tissue with star-shaped tubule lumens, indicative of healthy animals.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Tesis sobre el tema "Fucoidan"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros