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1.
Mar Drugs ; 22(6)2024 May 29.
Article de Anglais | MEDLINE | ID: mdl-38921562

RÉSUMÉ

Experiments conducted on triple-negative breast cancer have shown that fucoidan from Lessonia trabeculata (FLt) exhibits cytotoxic and antitumor properties. However, further research is necessary to gain a complete understanding of its bioactivity and level of cytotoxicity. The cytotoxic effect of FLt was determined by the 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Apoptosis was analyzed using annexin V and caspase 3/7 staining kit and DNA fragmentation. In addition, transcriptional expression of antiapoptotic (Bcl-2 and XIAP) and proapoptotic (caspase 8, caspase 9, and AIF) genes were analyzed in TNBC 4T1 cells. After 72 h of culture, the IC50 for FLt was 561 µg/mL, while doxorubicin (Dox) had an IC50 of 0.04 µg/mL. In addition, assays for FLt + Dox were performed. Annexin V and caspase 3/7 revealed that FLt induces early and late-stage apoptosis. DNA fragmentation results support necrotic death of 4T1 cells. Similarly, transcripts that prevent cell death were decreased, while transcripts that promote cell death were increased. This study showed that FLt induces apoptosis by both caspase-dependent and caspase-independent mechanisms. These findings suggest that FLt may have potential applications in breast cancer treatment. Further research will provide more information to elucidate the mechanism of action of FLt.


Sujet(s)
Apoptose , Caspases , Polyosides , Apoptose/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Polyosides/pharmacologie , Animaux , Femelle , Caspases/métabolisme , Souris , Antinéoplasiques/pharmacologie , Doxorubicine/pharmacologie , Humains , Adénocarcinome/traitement médicamenteux , Adénocarcinome/anatomopathologie , Fragmentation de l'ADN/effets des médicaments et des substances chimiques , Tumeurs du sein/traitement médicamenteux , Tumeurs du sein/anatomopathologie , Tumeurs du sein triple-négatives/traitement médicamenteux , Tumeurs du sein triple-négatives/anatomopathologie , Varech
2.
Toxins (Basel) ; 16(4)2024 Apr 12.
Article de Anglais | MEDLINE | ID: mdl-38668613

RÉSUMÉ

BACKGROUND: Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. METHODS: This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A2 (PLA2) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test. RESULTS: FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA2 activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms. CONCLUSION: FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil.


Sujet(s)
Coagulation sanguine , Venins de crotalidé , Fucus , Phospholipases A2 , Polyosides , Undaria , Animaux , Sérums antivenimeux/pharmacologie , Coagulation sanguine/effets des médicaments et des substances chimiques , Bothrops , Bothrops jararaca , Venins de crotalidé/toxicité , Venins de crotalidé/enzymologie , Edible Seaweeds/composition chimique , Fucus/composition chimique , Phospholipases A2/métabolisme , Polyosides/pharmacologie , Polyosides/isolement et purification , Protéolyse/effets des médicaments et des substances chimiques , Algue marine/composition chimique , Undaria/composition chimique , Venomous Snakes
3.
Rev. biol. trop ; Rev. biol. trop;71(1): e54918, dic. 2023. graf
Article de Anglais | LILACS, SaludCR | ID: biblio-1550731

RÉSUMÉ

Abstract Introduction: The therapeutic benefits of the brown algae fucoidan in the treatment of breast cancer have attracted considerable interest in recent years. However, research using spheroids which provide relevant results in trials for antitumor and immunomodulatory products because they adequately simulate the tumor microenvironment, is limited. Objective: To evaluate the antitumor and immunomodulatory activity of Lessonia trabeculata fucoidan (LtF), native to the Peruvian Sea, on two types of multicellular tumor spheroids. Methods: The study was conducted from January to December 2021. Two types of spheroides were elaborated: from 4T1 tumor cells (MTS), and from 4T1 tumor cells+mouse splenocytes (MTSs). The antitumor activity of LtF was evaluated in MTS by quantifying cell viability with MTT. Immunomodulatory activity was determined in MTSs using the IC50 for two types of treatment: simple, fucoidan alone (LtF) and combined, fucoidan+doxorubicin (LtF+Dox). Pro-inflammatory (TNF-α, IL-6) and anti-inflammatory (IL-10, TGF-β) cytokine production was quantified by sandwich ELISA 72 h after treatment. Dox was used as positive control in all assays. Results: LtF exerted antitumor activity as evidenced by increased necrotic zone and cell debris formation compared to the untreated control. Antitumor activity was concentration dependent between 100 and 6 000 μg/ml. In MTSs, simple treatment increased IL-6 and decreased IL-10 and TGF-β production. The combined treatment significantly reduced TGF-β production. In both treatments and Dox, there was an increase in IL-6 compared to the untreated control. The highest production of IL-10 and TGF-β was observed in the untreated control, compatible with a highly immunosuppressive tumor microenvironment. Conclusions: LtF is a good candidate for the treatment of breast cancer and can immunomodulate the tumor microenvironment alone or in combination with Dox.


Resumen Introduccción: Los beneficios terapéuticos del fucoidan de algas pardas en el tratamiento del cáncer de mama han despertado gran interés en los últimos años. Sin embargo, las investigaciones con esferoides son limitadas, éstos proporcionan resultados relevantes en ensayos de productos antitumorales e inmunomoduladores porque simulan adecuadamente el microambiente tumoral. Objetivo: Evaluar la actividad antitumoral e inmunomoduladora del fucoidan de Lessonia trabeculata (LtF), nativa del Mar Peruano, en dos tipos de esferoides tumorales multicelulares. Métodos: El estudio se realizó de enero a diciembre de 2021. Se elaboraron dos tipos de esferoides: con células tumorales 4T1 (MTS) y con células tumorales 4T1+esplenocitos de ratón (MTSs). La actividad antitumoral de LtF se evaluó en MTS cuantificando la viabilidad celular con MTT. La inmunomodulación se determinó en MTSs utilizando la IC50 para dos tipos de tratamiento: simple, fucoidan solo (LtF) y combinado, fucoidan+doxorubicina (LtF+Dox). La producción de citoquinas proinflamatorias (TNF-α, IL-6) y antiinflamatorias (IL-10, TGF-β) se cuantificó mediante ELISA sándwich 72 h post-tratamiento. En todos los ensayos se utilizó Dox como control positivo. Resultados: En los MTS, el LtF ejerció actividad antitumoral evidenciada por aumento de la zona necrótica y formación de restos celulares respecto al control no tratado. La actividad antitumoral fue concentración-dependiente entre 100 y 6 000 μg/ml. En los MTSs, con el tratamiento simple se incrementó IL-6 y disminuyeron IL-10 y TGF-β. El tratamiento combinado redujo significativamente la producción de TGF-β. Los dos tratamientos y Dox incrementaron IL-6 respecto al control no tratado. La mayor producción de IL-10 y TGF-β se observó en los no tratados, compatible con un microambiente tumoral altamente inmunosupresor. Conclusiones: El LtF es un buen candidato para tratar el cáncer de mama y puede inmunomodular el microambiente tumoral solo o en combinación con Dox.


Sujet(s)
Animaux , Sphéroïdes de cellules , Phaeophyceae , Antinéoplasiques/usage thérapeutique , Pérou
4.
Plants (Basel) ; 12(13)2023 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-37447006

RÉSUMÉ

Brown macroalgae represent one of the most proliferative groups of living organisms in aquatic environments. Due to their abundance, they often cause problems in aquatic and terrestrial ecosystems, resulting in health problems in humans and the death of various aquatic species. To resolve this, the application of Sargassum has been sought in different research areas, such as food, pharmaceuticals, and cosmetics, since Sargassum is an easy target for study and simple to obtain. In addition, its high content of biocompounds, such as polysaccharides, phenols, and amino acids, among others, has attracted attention. One of the valuable components of brown macroalgae is their polysaccharides, which present interesting bioactivities, such as antiviral, antimicrobial, and antitumoral, among others. There is a wide variety of methods of extraction currently used to obtain these polysaccharides, such as supercritical fluid extraction (SFE), pressurized liquid extraction (PLE), subcritical water extraction (SCWE), ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and microwave-assisted extraction (MAE). Therefore, this work covers the most current information on the methods of extraction, as well as the purification used to obtain a polysaccharide from Sargassum that is able to be utilized as alginates, fucoidans, and laminarins. In addition, a compilation of bioactivities involving brown algae polysaccharides in in vivo and in vitro studies is also presented, along with challenges in the research and marketing of Sargassum-based products that are commercially available.

5.
Life (Basel) ; 13(7)2023 Jul 11.
Article de Anglais | MEDLINE | ID: mdl-37511913

RÉSUMÉ

Boron neutron capture therapy (BNCT) is based on the preferential uptake of 10B compounds by tumors, followed by neutron irradiation. The aim of this study was to assess, in an ectopic colon cancer model, the therapeutic efficacy, radiotoxicity, abscopal effect and systemic immune response associated with (BPA/Borophenylalanine+GB-10/Decahydrodecaborate)-BNCT (Comb-BNCT) alone or in combination with Oligo-Fucoidan (O-Fuco) or Glutamine (GLN), compared to the "standard" BPA-BNCT protocol usually employed in clinical trials. All treatments were carried out at the RA-3 nuclear reactor. Boron biodistribution studies showed therapeutic values above 20 ppm 10B in tumors. At 7 weeks post-treatment, the ratio of tumor volume post-/pre-BNCT was significantly smaller for all BNCT groups vs. SHAM (p < 0.05). The parameter "incidence of tumors that underwent a reduction to ≤50% of initial tumor volume" exhibited values of 62% for Comb-BNCT alone, 82% for Comb-BNCT+GLN, 73% for Comb-BNCT+O-Fuco and only 30% for BPA-BNCT. For BPA-BNCT, the incidence of severe dermatitis was 100%, whereas it was significantly below 70% (p ≤ 0.05) for Comb-BNCT, Comb-BNCT+O-Fuco and Comb-BNCT+GLN. Considering tumors outside the treatment area, 77% of Comb-BNCT animals had a tumor volume lower than 50 mm3 vs. 30% for SHAM (p ≤ 0.005), suggesting an abscopal effect of Comb-BNCT. Inhibition of metastatic spread to lymph nodes was observed in all Comb-BNCT groups. Considering systemic aspects, CD8+ was elevated for Comb-BNCT+GLN vs. SHAM (p ≤ 0.01), and NK was elevated for Comb-BNCT vs. SHAM (p ≤ 0.05). Comb-BNCT improved therapeutic efficacy and reduced radiotoxicity compared to BPA-BNCT and induced an immune response and an abscopal effect.

6.
J Med Food ; 25(11): 1011-1020, 2022 Nov.
Article de Anglais | MEDLINE | ID: mdl-35984868

RÉSUMÉ

The rising prevalence of metabolic diseases represents a major challenge to public health worldwide. Therefore, there is a strong need to conduct research on the effectiveness of complementary and alternative therapies for metabolic disorders. Fucoidan is a fucose-enriched and sulfated polysaccharide extracted from ubiquitous brown seaweed. The antihypertensive, antidiabetic, antiobesity, and hypolipidemic effects of fucoidan have been reported in preclinical research and clinical trials. This study aims to review the mechanisms of action and the experimental and clinical use of different types of fucoidan for the treatment of metabolic diseases.


Sujet(s)
Maladies métaboliques , Algue marine , Humains , Polyosides/pharmacologie , Polyosides/usage thérapeutique , Algue marine/métabolisme , Maladies métaboliques/traitement médicamenteux
7.
Nanomaterials (Basel) ; 12(12)2022 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-35745396

RÉSUMÉ

The brown seaweed Spatoglossum schröederi synthesizes three bioactive fucoidans, the most abundant of which is fucan A. This fucoidan was extracted and its identity was confirmed by chemical analysis, Fourier-transform infrared spectroscopy (FTIR), and agarose gel electrophoresis. Thereafter, silver nanoparticles containing fucan A (AgFuc) were produced using an environmentally friendly synthesis method. AgFuc synthesis was analyzed via UV-vis spectroscopy and FTIR, which confirmed the presence of both silver and fucan A in the AgFuc product. Dynamic light scattering (DLS), X-ray diffraction, scanning electron microscopy, and atomic force microscopy revealed that the AgFuc particles were ~180.0 nm in size and spherical in shape. DLS further demonstrated that AgFuc was stable for five months. Coupled plasma optical emission spectrometry showed that the AgFuc particles contained 5% silver and 95% sugar. AgFuc was shown to be more effective in inhibiting the ability of parasites to reduce MTT than fucan A or silver, regardless of treatment time. In addition, AgFuc induced the death of ~60% of parasites by necrosis and ~17% by apoptosis. Therefore, AgFuc induces damage to the parasites' mitochondria, which suggests that it is an anti-Trypanosoma cruzi agent. This is the first study to analyze silver nanoparticles containing fucan as an anti-Trypanosoma cruzi agent. Our data indicate that AgFuc nanoparticles have potential therapeutic applications, which should be determined via preclinical in vitro and in vivo studies.

8.
Pharm Res ; 39(6): 1135-1150, 2022 Jun.
Article de Anglais | MEDLINE | ID: mdl-35233729

RÉSUMÉ

PURPOSE: This work investigated the endocytic pathways taken by poly(isobutylcyanoacrylate) (PIBCA) nanoparticles differing in their surface composition and architecture, assuming that this might determine their efficiency of intracellular drug delivery. METHODS: Nanoparticles (A0, A25, A100, R0, R25 ) were prepared by anionic or redox radical emulsion polymerization using mixtures of dextran and fucoidan (0, 25, 100 % in fucoidan). Cell uptake was evaluated by incubating J774A.1 macrophages with nanoparticles. Endocytic pathways were studied by incubating cells with endocytic pathway inhibitors (chlorpromazine, genistein, cytochalasin D, methyl-ß-cyclodextrin and nocodazole) and nanoparticle uptake was evaluated by flow cytometry and confocal microscopy. RESULTS: The fucoidan-coated PIBCA nanoparticles A25 were internalized 3-fold more efficiently than R25 due to the different architecture of the fucoidan chains presented on the surface. Different fucoidan density and architecture led to different internalization pathway preferred by the cells. Large A100 nanoparticles with surface was covered with fucoidan chains in a loop and train configuration were internalized the most efficiently, 47-fold compared with A0, and 3-fold compared with R0 and R25 through non-endocytic energy-independent pathways and reached the cell cytoplasm. CONCLUSION: Internalization pathways of PIBCA nanoparticles by J774A.1 macrophages could be determined by nanoparticle fucoidan surface composition and architecture. In turn, this influenced the extent of internalization and localization of accumulated nanoparticles within cells. The results are of interest for rationalizing the design of nanoparticles for potential cytoplamic drug delivery by controlling the nature of the nanoparticle surface.


Sujet(s)
Nanoparticules , Systèmes de délivrance de médicaments , Émulsions , Polyosides
9.
Mar Drugs ; 20(2)2022 Jan 24.
Article de Anglais | MEDLINE | ID: mdl-35200630

RÉSUMÉ

Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, anti-viral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for COVID-19 recovery. This work aimed to determine the ex-vivo effects of treatment with fucoidan (20 µg/mL) on mitochondrial membrane potential (ΔΨm, using a cationic cyanine dye, 3,3'-dihexyloxacarbocyanine iodide (DiOC6(3)) on human peripheral blood mononuclear cells (HPBMC) isolated from healthy control (HC) subjects, COVID-19 patients (C-19), and subjects that recently recovered from COVID-19 (R1, 40 ± 13 days after infection). In addition, ex-vivo treatment with fucoidan (20 and 50 µg/mL) was evaluated on ΔΨm loss induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP, 150 µM) in HPBMC isolated from healthy subjects (H) and recovered subjects at 11 months post-COVID-19 (R2, 335 ± 20 days after infection). Data indicate that SARS-CoV-2 infection induces HPBMC loss of ΔΨm, even 11 months after infection, however, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered subjects. Therefore, fucoidan may be a potential treatment to diminish long-term sequelae from COVID-19, using mitochondria as a therapeutic target for the recovery of cellular homeostasis.


Sujet(s)
COVID-19 , Agranulocytes/effets des médicaments et des substances chimiques , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Polyosides/pharmacologie , SARS-CoV-2 , Adulte , Sujet âgé , Femelle , Humains , Agranulocytes/physiologie , Mâle , Adulte d'âge moyen , Mitochondries/effets des médicaments et des substances chimiques , Phaeophyceae/composition chimique , Polyosides/composition chimique , Jeune adulte
10.
Sci Total Environ ; 806(Pt 2): 150657, 2022 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-34597566

RÉSUMÉ

Since 2014, the Mexican Caribbean beaches have received massive influxes of the brown seaweed Sargassum (S. fluitans III, S. natans I and S. natans VIII), causing serious ecological and economic effects. Concentrations of arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn) were determined over an annual cycle in pelagic Sargassum species from massive influxes into the Mexican Caribbean. The contribution of trace elements, polysaccharides (alginate and fucoidans), and their main functional groups (uronic acids and sulfate) to arsenic content in Sargassum fluitans - the most abundant species in the Sargassum influx - is discussed. Arsenic was recorded in all samples, yielding mean concentrations of 74.2 ± 2.84 mg kg-1. Significant differences were found between species for As, Cu, Fe, and Pb, but not for Cd and Zn; also, S. fluitans showed significant differences in metal content between seasons for all elements, as well as in alginate and uronic acids from fucoidan. The season of the year, copper, iron, uronic acids, and sulfate content in fucoidan were the main variables associated with arsenic accumulation in S. fluitans as evidenced with a Generalized Linear Model. Arsenic content in Sargassum biomass exceeded the maximum allowable level in the rainy season; therefore, the content of this trace element should be carefully monitored for safe usage of Sargassum biomass.


Sujet(s)
Arsenic , Sargassum , Oligoéléments , Caraïbe , Antilles
11.
Braz. J. Pharm. Sci. (Online) ; 58: e19542, 2022. graf
Article de Anglais | LILACS | ID: biblio-1384004

RÉSUMÉ

Abstract The main aim of the study is to quantify the cytotoxic property of the Fucoidan extracted from the Turbinaria conoides using the MTT assay with the standard fucose. Fucoidan was extracted using the soaked water method and it was determined using the HPLC procedure the obtained Test sample Fucoidan extracted from the Turbinaria conoides and standard fucose was subjected to the cytotoxicity assay against the MCF7 Human breast cancer cell line, A549 lung cancer cell line, and L929 normal mouse fibroblast cell line. From the results it was found that the Test sample showed good IC50 value for MCF7 cell line then A549 with an increasing concentration 24 hours incubation at 37°C The IC50 for MCF7 was 115.21 µg/ml and A549 396.46µg/ml and the Fucoidan extract was checked for its cytotoxicity against the normal mouse fibroblast cell line L929, Fucoidan was found non-lethal to the L929 mouse fibroblast normal cell line. Standard fucose also gave a significant result towards MCF7 and against the L929. This indicates that the Fucoidan extracted from Tubinaria conoides shows better anticancer potential in it. Hence its application can be further extended in the pharmacological fields.


Sujet(s)
Techniques in vitro/instrumentation , Cytotoxines/effets indésirables , Cellules MCF-7 , Cellules A549 , Tumeurs du sein/anatomopathologie , Lignée cellulaire , Chromatographie en phase liquide à haute performance/méthodes , Concentration inhibitrice 50 , Fibroblastes/classification , Fucose/analogues et dérivés , Tumeurs du poumon/anatomopathologie
12.
Mar Drugs ; 19(8)2021 Jul 27.
Article de Anglais | MEDLINE | ID: mdl-34436263

RÉSUMÉ

Marine organisms are a source of active biomolecules with immense therapeutic and nutraceutical potential. Sulfated fucose-rich polysaccharides are present in large quantities in these organisms with important pharmacological effects in several biological systems. These polysaccharides include sulfated fucan (as fucoidan) and fucosylated chondroitin sulfate. The development of these polysaccharides as new drugs involves several important steps, among them, demonstration of the effectiveness of these compounds after oral administration. The oral route is the more practical, comfortable and preferred by patients for long-term treatments. In the past 20 years, reports of various pharmacological effects of these polysaccharides orally administered in several animal experimental models and some trials in humans have sparked the possibility for the development of drugs based on sulfated polysaccharides and/or the use of these marine organisms as functional food. This review focuses on the main pharmacological effects of sulfated fucose-rich polysaccharides, with an emphasis on the antidislipidemic, immunomodulatory, antitumor, hypoglycemic and hemostatic effects.


Sujet(s)
Antinéoplasiques/pharmacologie , Organismes aquatiques , Chondroïtines sulfate/pharmacologie , Polyosides/pharmacologie , Administration par voie orale , Antinéoplasiques/administration et posologie , Chondroïtines sulfate/administration et posologie , Humains , Polyosides/administration et posologie
13.
Front Nutr ; 7: 163, 2020.
Article de Anglais | MEDLINE | ID: mdl-33072794

RÉSUMÉ

Macroalgae stand out for their high content of dietary fiber (30-75%) that include soluble, sulfated (fucoidan, agaran, carrageenan, and ulvan) and non-sulfated (laminaran and alginate) polysaccharides. Many studies indicate that these compounds exert varied biological activities and health-promoting effects and for this reason, there is a growing interest for using them in food products. The aim of this review was to critically evaluate prebiotic properties of algal polysaccharides, i.e., their ability to exert biological activities by modulating the composition and/or diversity of gut microbiota (GM). Pre-clinical studies show that the non-sulfated alginate and laminaran are well-fermented by GM, promoting the formation of short chain fatty acids (SCFAs) including butyrate, and preventing that of harmful putrefactive compounds (NH3, phenol, p-cresol, indole and H2S). Alginate increases Bacteroides, Bifidobacterium, and Lactobacillus species while laminaran mostly stimulates Bacteroides sp. Results with sulfated polysaccharides are more questionable. Agarans are poorly fermentable but agarose-oligosaccharides exhibit an interesting prebiotic potential, increasing butyrate-producing bacteria and SCFAs. Though carrageenan-oligosaccharides are also fermented, their use is currently limited due to safety concerns. Regarding fucoidan, only one study reports SCFAs production, suggesting that it is poorly fermented. Its effect on GM does not indicate a clear pattern, making difficult to conclude whether it is beneficial or not. Notably, fucoidan impact on H2S production has not been evaluated, though some studies report it increases sulfate-reducing bacteria. Ulvan is badly fermented by GM and some studies show that part of its sulfate is dissimilated to H2S, which could affect colonic mitochondrial function. Accordingly, these results support the use of laminaran, alginate and agaro-oligosaccharides as prebiotics while more studies are necessary regarding that of fucoidan, carrageenan and ulvan. However, the realization of clinical trials is necessary to confirm such prebiotic properties in humans.

14.
Mar Drugs ; 18(5)2020 Apr 28.
Article de Anglais | MEDLINE | ID: mdl-32354032

RÉSUMÉ

Fucoidans are sulphated polysaccharides that can be obtained from brown seaweed and marine invertebrates. They have anti-cancer properties, through their targeting of several signaling pathways and molecular mechanisms within malignant cells. This review describes the chemical structure diversity of fucoidans and their similarity with other molecules such as glycosaminoglycan, which enable them to participation in diverse biological processes. Furthermore, this review summarizes their influence on the development of metastasis and drug resistance, which are the main obstacles to cure cancer. Finally, this article discusses how fucoidans have been used in clinical trials to evaluate their potential synergy with other anti-cancer therapies.


Sujet(s)
Antinéoplasiques/usage thérapeutique , Tumeurs/traitement médicamenteux , Polyosides/usage thérapeutique , Algue marine/composition chimique , Résistance aux substances , Humains , Biologie marine , Métastase tumorale
15.
Int J Biol Macromol ; 145: 500-509, 2020 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-31874267

RÉSUMÉ

The in vivo antifibrotic effect of a fucoidan extract (FE) from Sargassum fluitans Borgesen was evaluated in a carbon tetrachloride-induced liver damage model in rats over twelve weeks. Chemical analysis showed the FE to contain carbohydrates, sulfates, uronic acids, protein, phenols, and to have a molecular weight of ~60 kDa. Physiological, biochemical, histological and genetic assays were done. Daily oral administration of FE (50 mg/kg) reduced liver enzymatic activity, liver infiltration of inflammatory cells, collagen fiber deposition and gene expression cytokines such as interleukin beta 1 (IL-ß1), tumor necrosis factor alpha (TNF-α), transforming growth factor beta 1 (TGF-ß1), Smad-3, Smad-2, collagen 1 alpha 1 (col1α1) and tissue inhibitor of metalloproteinase 1 (TIMP-1). It also increased RNA expression of Smad-7 and metalloproteinase 2 and 9 (MMP2 and MMP9). The fucoidan extract exhibited an antifibrotic effect mediated by the inhibiting TGF-ß1/Smad pathway, as well as anti-inflammatory effects.


Sujet(s)
Cirrhose du foie/traitement médicamenteux , Extraits de plantes/pharmacologie , Polyosides/composition chimique , Sargassum/composition chimique , Animaux , Tétrachloro-méthane/toxicité , Intoxication au tétrachlorure de carbone/traitement médicamenteux , Intoxication au tétrachlorure de carbone/génétique , Intoxication au tétrachlorure de carbone/anatomopathologie , Modèles animaux de maladie humaine , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Foie/effets des médicaments et des substances chimiques , Cirrhose du foie/induit chimiquement , Cirrhose du foie/anatomopathologie , Extraits de plantes/composition chimique , Polyosides/pharmacologie , Rats , Transduction du signal/effets des médicaments et des substances chimiques , Protéines Smad/génétique , Protéine Smad-3/génétique , Facteur de croissance transformant bêta/génétique , Facteur de croissance transformant bêta-1/génétique
16.
Polymers (Basel) ; 11(8)2019 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-31395803

RÉSUMÉ

Chitosan, fucoidan, and polyvinyl alcohol are categorized as polymers with biomedical applications. Ampicillin, on the other hand, is considered as an important antibiotic that has shown effectivity in both gram-positive and gram-negative micro-organisms. The aforementioned polymers possess unique properties that are considered desirable for cell regeneration although they exhibit drawbacks that can affect their final application. Therefore, films of these biomaterials were prepared and they were characterized using FTIR, SEM, XRD, degree of swelling and solubility, and MTT assay. The statistical significance of the experiments was determined using a two-way analysis of variance (ANOVA) with p < 0.05. The characterization techniques demonstrated that the obtained material exhibits properties suitable for cell regeneration, and that a higher concentration of natural polymers promotes cells proliferation to a greater extent. The presence of PVA, on the other hand, is responsible for matrix stability and dictates the degree of swelling and solubility. The SEM images demonstrated that neither aggregations nor clusters were formed, which is favorable for the biological properties without detrimental to the morphological and physical features. Cell viability was comparatively similar in samples with and without antibiotic, and the physical and biological properties were not negatively affected. Indeed, the inherent bactericidal effect of chitosan was reinforced by the presence of ampicillin. The new material is an outstanding candidate for cell regeneration as a consequence of the synergic effect that each component provides to the blend.

17.
Rev. peru. biol. (Impr.) ; 26(3)ago. 2019.
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1508843

RÉSUMÉ

Las algas pardas constituyen una fuente de alto contenido de polisacáridos como los fucoidanos que poseen importantes propiedades inmunomoduladoras. El objetivo fue determinar la viabilidad de células mononucleares de sangre periférica humana (CMSPh), producción de óxido nítrico (NO), especies reactivas de oxígeno (ROS) y de las citoquinas proinflamatorias IL-1α, IL-6, TNF-α e IFN-γ en cultivos tratados con fucoidan de Lessonia trabeculata. Se empleó fucoidan de Lessonia trabeculata proveniente de la bahía San Nicolás de Marcona-Ica. Las CMSPh se aislaron empleando Ficoll-Hypaque, se distribuyeron a una concentración de 1x105 células/pocillo en medio RPMI-1640 completo y se trataron con diferentes concentraciones de fucoidan durante 24 y 48 h. La actividad citotóxica se determinó por la reducción de MTT, la producción de NO por la reacción de Griess y las ROS por la reducción del NBT. La producción de citoquinas se cuantificó por ELISA. El fucoidan de L. trabeculata estimuló la proliferación de CMSPh y produjo el incremento de ROS a concentraciones de 100-2000 μg/mL respecto al control (p<0.001), la reacción para nitritos resultó negativa. El fucoidan incrementó la producción de IL-1α y TNF-α a concentraciones de 100 y 10 μg/mL respectivamente, mientras que la producción de IL-6 e IFN-γ no mostró diferencias significativas. Se concluye que el fucoidan de L. trabeculata estimula la proliferación de CMSPh, producción de especies reactivas de oxígeno y las citoquinas proinflamatorias IL-1α y TNF-α que poseen importantes propiedades inmunomoduladoras.


Brown algae are a source of high content of polysaccharides such as fucoidans that have important immunomodulatory properties. The aim was to determine the viability of human peripheral blood mononuclear cells (hPBMC), production of nitric oxide (NO), reactive oxygen species (ROS) and the proinflammatory cytokines IL-1α, IL-6, TNF-α and IFN -γ in cultures treated with fucoidan from Lessonia trabeculata. Fucoidan from Lessonia trabeculata from San Nicolás de Marcona-Ica Bay was used. The hPBMC were isolated using Ficoll-Hypaque, distributed at a concentration of 1x105 cells/well in complete RPMI-1640 medium and treated with different concentrations of fucoidan for 24 and 48 h. The cytotoxic activity was determined by the reduction of MTT, NO production by the Griess reaction and ROS by the reduction of NBT. The production of cytokines was quantified by ELISA. The fucoidan of L. trabeculata stimulated the proliferation of hPBMC and produced the increase of ROS at concentrations of 100-2000 μg/mL with respect to the control (p <0.001), the reaction for nitrites was negative. Fucoidan increased the production of IL-1α and TNF-α at concentrations of 100 and 10 μg/mL respectively, while the production of IL-6 and IFN-γ did not show significant differences. It is concluded that the fucoidan of L. trabeculata stimulates the proliferation of hPBMC, production of reactive oxygen species and the proinflammatory cytokines IL-1α and TNF-α that possess important immunomodulatory properties.

18.
J Innate Immun ; 11(4): 330-346, 2019.
Article de Anglais | MEDLINE | ID: mdl-30557873

RÉSUMÉ

Exposition of neutrophils (polymorphonuclear neutrophils, PMNs) to bacterial products triggers exacerbated activation of these cells, increasing their harmful effects on host tissues. We evaluated the possibility of interfering with the classic immune innate responses of human PMNs exposed to bacterial endotoxin (lipopolysaccharide, LPS), and further stimulated with bacterial formyl peptide (N-formyl-methionine-leucine-phenylalanine, fMLP). We showed that the low- molecular-weight fucoidan (LMW-Fuc), a polysaccharide extracted from brown algae, attenuated the exacerbated activation induced by fMLP on LPS-primed PMNs, in vitro, impairing chemotaxis, NET formation, and the pro-survival and pro-oxidative effects. LMW-Fuc also inhibited the activation of canonical signaling pathways, AKT, bad, p47phox and MLC, activated by the exposition of PMN to bacterial products. The activation of PMN by sequential exposure to LPS and fMLP induced the release of L-selectin+ microparticles, which were able to trigger extracellular reactive oxygen species production by fresh PMNs and macrophages. Furthermore, we observed that LMW-Fuc inhibited microparticle release from activated PMN. In vivo experiments showed that circulating PMN-derived microparticles could be detected in mice exposed to bacterial products (LPS/fMLP), being downregulated in animals treated with LMW-Fuc. The data highlight the autocrine and paracrine role of pro-inflammatory microparticles derived from activated PMN and demonstrate the anti-inflammatory effects of LMW-Fuc on these cells.


Sujet(s)
Microparticules membranaires/métabolisme , Pièges extracellulaires/métabolisme , Sélectine L/métabolisme , Granulocytes neutrophiles/immunologie , Polyosides/pharmacologie , Animaux , Survie cellulaire , Cellules cultivées , Chimiotaxie , Humains , Immunité innée , Lipopolysaccharides/immunologie , Souris , Souris de lignée BALB C , N-Formyl-méthionyl-leucyl-phénylalanine/immunologie , Activation des neutrophiles , Stress oxydatif , Phaeophyceae/immunologie , Espèces réactives de l'oxygène/métabolisme , Transduction du signal
19.
Int Immunopharmacol ; 62: 96-108, 2018 Sep.
Article de Anglais | MEDLINE | ID: mdl-29990699

RÉSUMÉ

Ifosfamide (IFO) is an antineoplastic drug that is commonly used to treat gynecological and breast cancers. Hemorrhagic cystitis (HC) is a common side effect associated with IFO injection, which courses with neutrophil accumulation and affects 6-50% of patients depending on dose intensity. Here, we investigated the role of neutrophils in this inflammatory process. Female Swiss mice (n = 8/group) were injected with saline, IFO (400 mg/kg, i.p.), fucoidan (a P- and L-selectins inhibitor, 100 mg/kg, i.v.) or IFO + fucoidan (1-100 mg/kg) alone or combined with mesna (80 mg/kg i.p.). Another group of mice received anti-Ly6G antibody (500 µg/mouse, once daily for 2 days) for neutrophil depletion before IFO injection. In another experimental setting, animals received granulocyte colony-stimulating factor (G-CSF, 400 µg/kg), IFO (200 mg/kg), G-CSF (25-400 µg/kg, for 5 days) + IFO (200 mg/kg, i.p.) or fucoidan + G-CSF + IFO. Bladder injury was evaluated 12 h after IFO injection. IFO 400 mg/kg significantly increased visceral hyperalgesia, bladder edema, hemorrhage, vascular permeability, MPO, IL-1ß and IL-6 tissue levels, and COX-2 immunostaining and expression versus the saline group (P < 0.05). Conversely, fucoidan (100 mg/kg) significantly attenuated these parameters compared to IFO-injected mice (P < 0.05). Additionally, fucoidan potentiated mesna protective effect when compared with IFO + mesna group (P < 0.05). Accordingly, neutrophil depletion with anti-Ly6G reduced inflammatory parameters and bladder injury compared to IFO (P < 0.05). In contrast, G-CSF enhanced IFO (200 mg/kg)-induced HC, which was significantly attenuated by treatment with fucoidan (P < 0.05). Therefore, neutrophils contribute to the pathogenesis of HC.


Sujet(s)
Antinéoplasiques alcoylants/effets indésirables , Cystite/induit chimiquement , Hémorragie/induit chimiquement , Ifosfamide/effets indésirables , Infiltration par les neutrophiles/effets des médicaments et des substances chimiques , Agents protecteurs/usage thérapeutique , Animaux , Cystite/immunologie , Cystite/anatomopathologie , Cystite/prévention et contrôle , Association de médicaments , Femelle , Hémorragie/immunologie , Hémorragie/anatomopathologie , Hémorragie/prévention et contrôle , Mesna/administration et posologie , Mesna/usage thérapeutique , Souris , Polyosides/administration et posologie , Polyosides/usage thérapeutique , Agents protecteurs/administration et posologie
20.
Nanotechnology ; 2018 Feb 09.
Article de Anglais | MEDLINE | ID: mdl-29424698

RÉSUMÉ

Fucoidan-loaded nanoparticles emerge as great candidates to oral anticoagulant therapy, due to increasing of bioavailability and circulation time of this natural anticoagulant. Crosslink between chitosan chains are performed using glutaraldehyde to confer higher gastric pH resistance to nanoparticle matrices. In this work, chitosan-fucoidan nanoparticles, without (NpCF) and with glutaraldehyde crosslink (NpCF 1% and NpCF 2%), were prepared to evaluate their anticoagulant, antithrombotic and hemorrhagic profile. Nanoparticles were characterized by average diameter, polydispersity index, zeta potential, Fourier transform infrared spectroscopy and fucoidan in vitro release. Anticoagulant and antithrombotic activities were determined by in vitro and in vivo models, respectively. Hemorrhagic profile was in vivo evaluated by tail bleeding assay. Preparations showed nanometric and homogeneous average diameters. Zeta potentials of NpCF and NpCF 1% were stable over gastrointestinal pH range, which was confirmed by low fucoidan release in gastric and enteric media. In pH 7.4, NpCF and NpCF 1% demonstrated fucoidan release of 65.5% and 60.6%, respectively, within the first 24 hours. In comparison to fucoidan, NpCF and NpCF 1% showed increased in vitro anticoagulant activity. A significant difference on oral antithrombotic profile of NpCF 1% was found in comparison to fucoidan. Bleeding profile of NpCF and NpCF 1% showed no differences to control group, indicating the safety of these systems. Surprisingly, oral antithrombotic profile of commercially available fucoidan, from Fucus vesiculosus, has not been previously determined, which reveals new possibilities. In this work, significant advances were observed in anticoagulant and antithrombotic profiles of fucoidan through the preparation of NpCF 1%.

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