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1.
Food Chem ; 333: 127456, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663750

RESUMO

Bioprospecting for seaweed-derived multimodal acting products have earned increasing attention in the fight against diseases of multifactorial origin, such as neurodegenerative conditions. This is a pioneer study on the in vitro screening of neuroactive properties of phlorotannin-targeted extracts from edible Fucus species. Phlorotannin extracts exhibited multifunctional antioxidant properties, which were suggested to be responsible for counteracting glutamate toxicity in neuronal human-derived SH-SY5Y cells. They also inhibited the activity of enzymes (cholinesterases, monoaminoxidases A and B, and tyrosinase) linked to a set of events that contribute to the onset/progression of neurodegeneration. In general, the bioactivities were correlated with the total phlorotannin content and phloroglucinol tetramers were suggested to be behind the observed effects. The capacity of the phlorotannin extracts to interact with multiple in vitro targets underpinning neurodegeneration points to the potential interest of the selected seaweed species for development of new added-value products and promising neuroactive agents.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Fucus/química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Alimentos , Ácido Glutâmico/toxicidade , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Neurônios/efeitos dos fármacos , Floroglucinol/química , Floroglucinol/farmacologia , Polifenóis/química , Polifenóis/farmacologia , Análise de Componente Principal , Alga Marinha/química
2.
Mar Drugs ; 18(4)2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32331442

RESUMO

The enzymatic depolymerization of fucoidans from brown algae allowed the production of their standardized derivatives with different biological activities. This work aimed to compare the antiviral activities of native (FeF) and modified with enzyme (FeHMP) fucoidans from F. evanescens. The cytotoxicity and antiviral activities of the FeF and FeHMP against herpes viruses (HSV-1, HSV-2), enterovirus (ECHO-1), and human immunodeficiency virus (HIV-1) in Vero and human MT-4 cell lines were examined by methylthiazolyltetrazolium bromide (MTT) and cytopathic effect (CPE) reduction assays, respectively. The efficacy of fucoidans in vivo was evaluated in the outbred mice model of vaginitis caused by HSV-2. We have shown that both FeF and FeHMP significantly inhibited virus-induced CPE in vitro and were more effective against HSV. FeF exhibited antiviral activity against HSV-2 with a selective index (SI) > 40, and FeHMP with SI ˃ 20, when they were added before virus infection or at the early stages of the HSV-2 lifecycle. Furthermore, in vivo studies showed that after intraperitoneal administration (10 mg/kg), both FeF and FeHMP protected mice from lethal intravaginal HSV-2 infection to approximately the same degree (44-56%). Thus, FeF and FeHMP have comparable potency against several DNA and RNA viruses, allowing us to consider the studied fucoidans as promising broad-spectrum antivirals.


Assuntos
Antivirais/farmacologia , Fucus/química , Polissacarídeos/farmacologia , Vírus/efeitos dos fármacos , Animais , Antivirais/isolamento & purificação , Chlorocebus aethiops , Vírus de DNA/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Polissacarídeos/isolamento & purificação , Vírus de RNA/efeitos dos fármacos , Vaginite/tratamento farmacológico , Vaginite/virologia , Células Vero
3.
Chemosphere ; 244: 125595, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050355

RESUMO

This work reports comprehensive time-series datasets for 137Cs and 99Tc in marine samples from the Danish Straits over the past 40 years, where dynamic inputs from the two European nuclear reprocessing plants Sellafield (SF) and La Hague (LH) and Chernobyl accident are clearly archived. Distinct seasonal variations between 137Cs and 99Tc are observed in Fucus vesiculosus (F. vesiculosus), which needs to be taken into account when using F. vesiculosus as a bio-monitor to represent the concentration of radionuclides in seawater. Comparable transfer factor (TF) for 99Tc from SF to Kattegat between our calculation and earlier studies indicates a relatively steady water mass transport over the past decades. Three distinct events are observed in the temporal evolution of 99Tc/137Cs activity ratio in F. vesiculosu with the first event corresponding with the increased 99Tc discharge from SF, while the other two are very likely related to the major Baltic inflow (MBI) events. The correlation between the 99Tc/137Cs activity ratio and salinity fits well into the binary mixing line with the North Sea (NS) and the Baltic Sea (BS) as end members. A model simulation indicates that water mass from NS constitutes less than 50% in the surface water and 50-100% for most locations in the bottom water of the Danish Straits. Overall observations show that 137Cs and 99Tc in marine samples, especially 99Tc/137Cs isotope ratios, serve as useful oceanic tracers to study different natural processes, such as water mixing and transport dynamics.


Assuntos
Radioisótopos de Césio/análise , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Contaminação Radioativa da Água/estatística & dados numéricos , Países Bálticos , Dinamarca , Fucus/química , Mar do Norte , Oceanos e Mares , Salinidade , Água do Mar , Água
4.
Mar Drugs ; 18(2)2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32046368

RESUMO

Fucoidan is a brown algae-derived polysaccharide having several biomedical applications. This study simultaneously compares the anti-cancer activities of crude fucoidans from Fucus vesiculosus and Sargassum filipendula, and effects of low (LMW, 10-50 kDa), medium (MMW, 50-100 kDa) and high (HMW, >100 kDa) molecular weight fractions of S. filipendula fucoidan against osteosarcoma cells. Glucose, fucose and acid levels were lower and sulphation was higher in F. vesiculosus crude fucoidan compared to S. filipendula crude fucoidan. MMW had the highest levels of sugars, acids and sulphation among molecular weight fractions. There was a dose-dependent drop in focal adhesion formation and proliferation of cells for all fucoidan-types, but F. vesiculosus fucoidan and HMW had the strongest effects. G1-phase arrest was induced by F. vesiculosus fucoidan, MMW and HMW, however F. vesiculosus fucoidan treatment also caused accumulation in the sub-G1-phase. Mitochondrial damage occurred for all fucoidan-types, however F. vesiculosus fucoidan led to mitochondrial fragmentation. Annexin V/PI, TUNEL and cytochrome c staining confirmed stress-induced apoptosis-like cell death for F. vesiculosus fucoidan and features of stress-induced necrosis-like cell death for S. filipendula fucoidans. There was also variation in penetrability of different fucoidans inside the cell. These differences in anti-cancer activity of fucoidans are applicable for osteosarcoma treatment.


Assuntos
Linhagem Celular Tumoral/efeitos dos fármacos , Polissacarídeos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Fucus/química , Humanos , Mitocôndrias/efeitos dos fármacos , Peso Molecular , Osteossarcoma , Feófitas/química , Sargassum/química
5.
Mar Drugs ; 18(1)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936539

RESUMO

Marine organisms are sources of several natural compounds with potential clinical use. However, only a few marine-based pharmaceuticals have been approved for use due to limited knowledge on their biological activities. Here, we identified the functional role of fucoidan extracted from Fucus vesiculosus on ovarian cancer. Fucoidan increased the death of ES-2 and OV-90 cells, through a reduction in proliferation, cell cycle arrest, releases of cytochrome c, reactive oxygen species (ROS) generation, and endoplasmic reticulum (ER) stress. Additionally, fucoidan increased the concentration of cytosolic and mitochondrial calcium in both cells. The decrease of cell proliferation was controlled by the inactivation of PI3K and MAPK signaling cascades in ES-2 and OV-90 cells. In a toxicity assay with normal zebrafish larvae, fucoidan did not induce toxicity, cardiotoxicity, development, kinesis, and apoptosis at different concentrations. However, it disrupted tumor formation and vascular development in a zebrafish xenograft model and angiogenesis transgenic (Tg, fli1-eGFP) model, respectively. Collectively, the results indicate that fucoidan may be a novel pharmaceutical for the management of human ovarian cancer.


Assuntos
Cálcio/metabolismo , Fucus/química , Homeostase/efeitos dos fármacos , Polissacarídeos/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Neovascularização Patológica/prevenção & controle , Neoplasias Ovarianas/tratamento farmacológico , Polissacarídeos/toxicidade , Testes de Toxicidade , Peixe-Zebra
6.
Mar Drugs ; 18(1)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963560

RESUMO

The Asian coastal communities have used the brown seaweeds Fucus vesiculosus and Ascophyllum nodosum since ancient times. Recently, some in vitro and in vivo studies have demonstrated their abilities in reducing risk factors for metabolic syndrome. Here, we analyzed the protective effect of a phytocomplex extracted from these seaweeds on the deposition of fat in the liver after the administration of a high-fat diet (HFD) to rats for five weeks. The administration of F. vesiculosus and A. nodosum led to significant reductions in microvescicular steatosis and plasma biochemical and lipid parameters, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total and conjugated bilirubin, and triglycerides. Furthermore, the postprandial glycemic peak was delayed and significantly reduced (p < 0.01) by the algal extract administration. In conclusion, this extract is effective in reducing microvescicular steatosis and improving glycemic control, thereby lowering the risk of nonalcoholic fatty liver disease, obesity, and diabetes, diseases related to the consumption of fat and sugar-enriched diets.


Assuntos
Ascophyllum/química , Dieta Redutora/efeitos adversos , Fucus/química , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Extratos Vegetais/farmacologia , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Glicemia/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Período Pós-Prandial/efeitos dos fármacos , Ratos , Ratos Wistar , Alga Marinha/química , Triglicerídeos/metabolismo
7.
Carbohydr Polym ; 230: 115604, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887959

RESUMO

Conductive natural-based separators for application in polymer electrolyte fuel cells (PEFCs) were fabricated by combining a bacterial polysaccharide, i.e. bacterial cellulose (BC), and an algae sulphated polysaccharide, i.e. fucoidan (Fuc). The diffusion of fucoidan aqueous solution containing a natural-based cross-linker, viz. tannic acid, into the wet BC nanofibrous three-dimensional network, followed by thermal cross-linking, originated fully bio-based proton exchange membranes (PEMs). The PEMs present thermal-oxidative stability in the range of 180-200 °C and good dynamic mechanical performance (storage modulus ≥ 460 MPa). Additionally, the BC/Fuc membranes exhibit protonic conductivity that increases with increasing relative humidity (RH), which is a typical feature for numerous water-mediated proton conductors. The traditional Arrhenius-type plots demonstrate a linear behaviour with a maximum protonic conductivity of 1.6 mS cm-1 at 94 °C and 98 % RH. The results showed that these fully bio-based conductive membranes have potential as eco-friendly alternatives to other PEMs for application in PEFCs.


Assuntos
Fontes de Energia Bioelétrica , Celulose/análogos & derivados , Membranas Artificiais , Polissacarídeos/química , Prótons , Condutividade Elétrica , Fucus/química , Temperatura Alta , Oxirredução
8.
Chemosphere ; 238: 124652, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31473524

RESUMO

This research aimed to find the best phenotype of the brown algae Fucus vesiculosus (kelp) which has the greater potential to become a sorption byproduct for Zn removal from contaminated waters. Thus, the Zn uptake capacity and sorption mechanisms of the kelp collected from the Baltic Sea shore was, for the first time, investigated under various conditions, and compared to the phenotype habiting on the Irish Sea shore. Sorption studies were performed investigating the effect of algal dosage, Zn sources as well as algal harvesting time of the year on Zn uptake capacity. The results suggested that the Baltic algae is a better bio-sorbent for Zn uptake. Sorption mechanisms were studied by employing various indirect and direct approaches, more importantly, including high resolution synchrotron X-Ray Fluorescence and X-Ray Absorption Spectroscopy (XAS) and molecular modelling (MM). The results revealed that alginate and cellulose are among the main polysaccharide bonding Zn at algal surface, via coordination with O atoms from carboxyl and hydroxyl groups. XAS results giving direct measurements of Zn bonding environment on algal surface are supported by MM outputs and suggested that Zn is surrounded by ca. 5 O atoms at interatomic distances varying from 1.94 to 2.02 Å. The results contribute to understanding sorption mechanisms which can further lead to finding the best eluent for Zn desorption from the used biomass, bio sorbent reconditioning and reuse in multiple sorption desorption cycles as well as process optimization before industrial scaling up.


Assuntos
Biodegradação Ambiental , Fucus/metabolismo , Zinco/isolamento & purificação , Absorção Fisico-Química , Alginatos/metabolismo , Biomassa , Celulose/metabolismo , Fucus/química , Reciclagem/métodos , Zinco/farmacocinética
9.
J Chromatogr A ; 1612: 460658, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703890

RESUMO

Fucoidans represent an intriguing class of fucose-containing sulfated polysaccharides. The biological activities of these polysaccharides are related to their compositional and structural parameters, whereby their degree of sulfation, as well as molecular weight (MW) distribution and chain conformation play important roles. Modern NMR and mass spectrometry techniques allow elucidating details of the glycan structure, but not the structure of the whole molecules in their native state. Accordingly, the knowledge about the latter of the fucoidans is currently still limited. Contrary to traditional MW determination by SEC with column calibration, SEC with triple detection provides not only the absolute Mw, but can also give information on additional molecule characteristics. In the present study, we used this method to compare six fucoidans extracted from Fucus vesiculosus (FV), F. serratus (FS), F. evanescens (FE), Dictyosiphon foeniculaceus (DF), Laminaria digitata (LD), and Saccharina latissima (SL) concerning their molar mass (Mw, Mn, Mp, dispersity) and size (rms radius, Rh) characteristics and distribution as well as their chain conformation in solution. The tested fucoidans displayed considerable structural diversity including large differences in their MW profiles and showed to be heterogeneously composed. Fuc-FV and Fuc-SL showed the broadest MW distributions, those from Fuc-FE and Fuc-DF the narrowest ones. Most of the fucoidan fractions (except for Fuc-DF) turned out to exist as expanded flexible chains in PBS solution. The conformation data suggest branched structures with partly long side chains. The knowledge obtained by this study is useful for further fractionation and structural characterization as well as the interpretation of the bioactivity differences between the various fucoidans.


Assuntos
Feófitas/química , Polissacarídeos/química , Configuração de Carboidratos , Cromatografia em Gel , Fucus/química , Peso Molecular
10.
Sci Rep ; 9(1): 17911, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784603

RESUMO

Antimicrobial resistant strains of infection are afflicting clinical settings, driving the search for novel antimicrobial compounds. Naturally sourced bioactives, for instance those from seaweeds, have the potential to ameliorate this issue. As such, solvent extracts from the edible Irish seaweeds Fucus serratus and Fucus vesiculosus were screened for antimicrobial activity against 28 clinically isolated strains of MRSA, including one GISA (glycopeptide intermediate S. aureus) and two mecC gene containing strains. The water extract of F. vesiculosus was the most promising extract went on to be tested for biofilm prevention and disruption activity. The disk diffusion method was used to investigate the inhibition of the bacterial pathogens tested while MIC, MBC and biofilm disruption and prevention analyses were performed spectroscopically and by plate counts, respectively. Solvent extracts were found to have a wide array of antimicrobial activity against the strains tested, with the water extract from Fucus vesiculosus being the most promising. This extract was also found to both prevent and disrupt MRSA biofilms indicating the potential extract as new antimicrobials, and raising the possibility of their possible use in therapeutics.


Assuntos
Antibacterianos/farmacologia , Fucus/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antibacterianos/toxicidade , Biofilmes/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Extratos Vegetais/toxicidade
11.
Molecules ; 24(19)2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569357

RESUMO

In this study, potential antifungal properties of a brown alga Fucus vesiculosus were evaluated. The algal extract was obtained with the use of supercritical fluid extraction (scCO2) at a temperature of 50 °C under a pressure of 300 bar. The aqueous solution of the extract at the concentration of 0.05%, 0.2%, 0.5% and 1.0% was studied against pathogenic fungi on a liquid RB medium. This study is the first report on antifungal properties of the brown algae F. vesiculosus scCO2 extract against Fusarium culmorum and Fusarium oxysporum phytopathogens. The concentrations of the studied extract (0.5% and 1.0%) were demonstrated to have an ability to inhibit 100% growth of macroconidia within 144 h, as well as an ability to cause their total degradation. As a result of the study, the antifungal effect of fucosterol against F. culmorum was also indicated. The total macroconidia growth was inhibited by 1.0% fucosterol. Moreover, at lower concentrations (0.05-0.2%) of fucosterol, macroconidia were characterized by shorter length and structural degradation was observed. The mycelial growth of Fusarium oxysporum (Fo38) by 1% scCO2 F. vesiculosus extract was analyzed at the level of 48% after 168 h of incubation, whereas 100% extract was found to be effective in F. culmorum (CBS122) and F. oxysporum (Fo38) growth inhibition by 72% and 75%, respectively after 168 h of incubation.


Assuntos
Antifúngicos/farmacologia , Fucus/química , Fusarium/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/isolamento & purificação , Fracionamento Químico , Testes de Sensibilidade Microbiana
12.
Mar Drugs ; 17(9)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527536

RESUMO

Fucoidan extracts may have beneficial effects in age-related macular degeneration(AMD). Over-the-counter fucoidan preparations are generally undefined, crude extracts. In thisstudy, we investigated the effect of a crude fucoidan extract from Fucus distichus subspeciesevanescens (Fe) on the retinal pigment epithelium (RPE). Fe extract was investigated for chemicalcomposition and molar mass. It was tested in primary RPE and RPE cell line ARPE19. Oxidativestress was induced with tert-butyl hydroperoxide, cell viability evaluated with MTT assay, VEGFsecretion assessed in ELISA. Phagocytosis was evaluated in a fluorescence microscopic assay.Wound healing ability was tested in a scratch assay. Additionally, the inhibition of elastase andcomplement system by Fe extract was studied. The Fe extract contained about 61.9% fucose andhigh amounts of uronic acids (26.2%). The sulfate content was not as high as expected (6.9%). It wasnot toxic and not protective against oxidative stress. However, Fe extract was able to reduce VEGFsecretion in ARPE19. Phagocytosis was also reduced. Concerning wound healing, a delay could beobserved in higher concentrations. While some beneficial effects could be found, it seems tointerfere with RPE function, which may reduce its beneficial effects in AMD treatment.


Assuntos
Fucus/química , Degeneração Macular/tratamento farmacológico , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular , Avaliação Pré-Clínica de Medicamentos , Humanos , Degeneração Macular/patologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Polissacarídeos/isolamento & purificação , Polissacarídeos/uso terapêutico , Cultura Primária de Células , Epitélio Pigmentado da Retina/metabolismo , Suínos , Testes de Toxicidade , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos
13.
Molecules ; 24(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546839

RESUMO

Brown macroalgae, particularly those from Fucus genus, are a rich and balanced source of bioactive nutrients and phytochemicals, such as dietary fibres (fucoidans, laminarins, and/or alginates), phlorotannins, and fucoxanthin, and some minerals, such as iodine, which have been demonstrated to possess numerous health-promoting properties. In fact, aqueous extracts of Fucus vesiculosus have been used as food supplements due to its rich content in bioactive compounds, though no study has been published on the optimization of this operation. Therefore, this study aimed to evaluate the impact of different extraction temperatures (25 °C, 50 °C, 75 °C, 100 °C, and 120 °C) and times (5 min, 1 h, 2 h, and 4 h) on the recovery of those bioactive compounds. The temperature was observed to positively influence the extraction of crude mass and of fucose polysaccharides only at 75 °C and above, and of iodine extraction at 50 °C and above. At these temperatures, time also showed to increase yields. Yields of crude extract, fucose, and iodine were successfully mathematically modelled with a power law, and its maximum yields were obtained at the highest temperature studied (120 °C) and longest extraction time (4 h). Iodine yield at these conditions provided extracts with relevant content to contribute to the recommended daily ingestion. Phlorotannins were significantly recovered at 120 °C though evidence of degradation was observed during time.


Assuntos
Fucus/química , Compostos Fitoquímicos/isolamento & purificação , Água/química , Benzotiazóis/química , Misturas Complexas , Depuradores de Radicais Livres/química , Fucose/análise , Iodo/análise , Cinética , Ácidos Sulfônicos/química
14.
Molecules ; 24(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547311

RESUMO

Recent studies have reported that dietary fiber improved metabolic syndrome (MetS). However, the effects of fucoidans on MetS were still not clear. In this study, we evaluated the activity of fucoidan from Fucus vesiculosus (FvF) on attenuating MetS and first elucidated the underlying mechanism. In vitro, FvF treatment remarkably lowered the level of reactive oxygen species (ROS) compared with the sodium palmitate (PA)-induced insulin resistance (IR) group. The phosphorylation level of c-Jun N-terminal kinase (JNK) was significantly decreased, while phosphorylation of protein kinase B (pAkt) level increased, compared with that of the HepG2 cells treated with PA. Thus, FvF increased glucose consumption and relieved IR via ROS-mediated JNK and Akt signaling pathways. In addition, these changes were accompanied by the activation of adenosine 5'-monophosphate-ativated protein kinase (AMPK) and its downstream targets (e.g., HMG-CoA reductase (HMGCR), acetyl-CoA carboxylase (ACC), and sterol-regulatory element-binding protein-1c (SREBP-1C)), which improved lipid metabolism in IR HepG2 cells. In vivo, FvF improved hyperglycemia and decreased serum insulin level in mice with MetS. Furthermore, we evaluated the inhibition of glucose transport by in vitro (Caco-2 monolayer model), semi-in vivo (everted gut sac model) and oral glucose tolerance test (OGTT), which indicated that FvF could significantly reduce the absorption of glucose into the blood stream, thus it could improve blood-glucose levels and IR in mice with MetS. Moreover, FvF decreased serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels and liver lipid accumulation, while increased the serum high density lipoprotein cholesterol (HDL-C) level in mice with MetS. Therefore, FvF could be considered as a potential candidate for the treatment of MetS by alleviating IR, inhibiting glucose transportation, and regulating lipid metabolism.


Assuntos
Fucus/química , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Polissacarídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Células Hep G2 , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Carbohydr Polym ; 223: 115034, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426965

RESUMO

Fucoidan is a marine-origin sulfated polysaccharide that can show anticancer activity, to which both pro- and anti-angiogenic responses have been reported. Due to this unpredictability, the angiogenic potential of an effective anticancer crude fucoidan (CF), at a concentration of 0.5 mg mL-1, was evaluated. Tube formation assays demonstrated that CF, either administered while endothelial cells seeding or after their adhesion, migration and organization, inhibited or disrupted the formation of tubular-like structures, respectively. Although CF did not significantly reduced vascular endothelial growth factor (VEGF) secretion, it significantly reduced the expression of platelet-derived growth factor (PDGF), compromising the blood vessels maturation. Two chicken embryo chorioallantoic membrane (CAM) assays were performed: one without tumor (CAM I) and the other with an onplanted tumor mass (CAM II); the CF injection reduced the number of blood of vessels and significantly decreased the tumor size, respectively. In vitro and in vivo results support the effectiveness of fucoidan as a natural antitumor therapeutic agent.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Fucus/química , Neovascularização Patológica/tratamento farmacológico , Polissacarídeos/uso terapêutico , Inibidores da Angiogênese/farmacologia , Animais , Linhagem Celular , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Humanos , Polissacarídeos/farmacologia , Microambiente Tumoral/efeitos dos fármacos
16.
Mar Drugs ; 17(8)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357497

RESUMO

Fucoidans extracted from brown algae exert manifold biological activities paving the way for the development of numerous applications including treatments outside tumor therapy such as age-related macular degeneration or tissue engineering. In this study, we investigated the antiproliferative effects of fucoidans extracted from six different algae (Fucus vesiculosus, F. serratus, F. distichus subsp. evanescens, Dictyosiphon foeniculaceus, Laminaria digitata, Saccharina latissima) as well as three reference compounds (Sigma fucoidan, heparin, enoxaparin) on tumor (HL-60, Raji, HeLa, OMM-1, A-375, HCT-116, Hep G2) and non-tumor (ARPE-19, HaCaT) cell lines. All fucoidans were extracted according to a standardized procedure and tested in a commercially available MTS assay. Cell viability was measured after 24 h incubation with test compounds (1-100 µg/mL). Apart from few exceptions, fucoidans and heparins did not impair cell viability. In contrast, fucoidans significantly increased cell viability of suspension cell lines, but not of adherent cells. Fucoidans slightly increased viability of tumor cells and had no impact on the viability of non-tumor cells. The cell viability of HeLa and ARPE-19 cells negatively correlated with protein content and total phenolic content (TPC) of fucoidans, respectively. In summary, none of the tested fucoidans turned out to be anti-proliferative, rendering them interesting for future studies and applications.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Polissacarídeos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fucus/química , Células HCT116 , Células HL-60 , Células HeLa , Células Hep G2 , Humanos , Feófitas/química
17.
Mar Drugs ; 17(6)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167455

RESUMO

Fucus vesiculosus is an edible brown macroalga, with health benefits associated with its consumption and also a source of bioactive molecules. It is acknowledged that the biochemical composition of macroalgae changes when exposed to different environmental conditions occurring on different habitats, such as the water temperature, and light intensity. In the present study, the polar lipidome of Fucus vesiculosus was characterized for the first time using modern high-resolution HILIC-MS, and MS/MS approaches, to evaluate the phenotypic variability in two seasons of the year, e.g., winter and spring. A total of 187 molecular species were identified over eighteen classes of glycolipids, phospholipids and betaine lipids. Principal component analysis (PCA) multivariate statistical analysis and cluster analysis of polar lipid classes, polar lipid species and total fatty acids (FA) datasets, showed clustering according to the seasonal groups. While the lipid profile of Fucus vesiculosus harvested in the winter and spring yielded the same molecular species, the relative abundance of these species was significantly different. In the winter, changes were mainly due to the increased relative abundance of some molecular species of glycolipids and phospholipids, bearing octadeca(poly)enoic (18:3, 18:4) and eicosa(poly)enoic (20:4, 20:5) FA and betaine lipids species with short saturated FA (14:0) and polyunsaturated FA (PUFA). Importantly, glycolipids with n-3 PUFA and sulfolipids, have been reported to have important biological activities and therapeutic value. Overall, Fucus vesiculosus is a promising source of bioactive compounds that can be used as functional food or ingredients for human nutrition, feed, pharma, and cosmetic formulations. In this study, samples harvested in the winter season maximized yields of these bioactive components, when compared with samples harvested in the spring.


Assuntos
Fucus/química , Lipídeos/química , Estações do Ano , Fucus/metabolismo , Lipídeos/análise , Espectrometria de Massas , Compostos Fitoquímicos/química
18.
Mar Drugs ; 17(4)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934874

RESUMO

Seaweeds are of significant interest in the food, pharmaceutical, and agricultural industries as they contain several commercially relevant bioactive compounds. Current extraction methods for macroalgal-derived metabolites are, however, problematic due to the complexity of the algal cell wall which hinders extraction efficiencies. The use of advanced extraction methods, such as enzyme-assisted extraction (EAE), which involve the application of commercial algal cell wall degrading enzymes to hydrolyze the cell wall carbohydrate network, are becoming more popular. Ascophyllum nodosum samples were collected from the Irish coast and incubated in artificial seawater for six weeks at three different temperatures (18 °C, 25 °C, and 30 °C) to induce decay. Microbial communities associated with the intact and decaying macroalga were examined using Illumina sequencing and culture-dependent approaches, including the novel ichip device. The bacterial populations associated with the seaweed were observed to change markedly upon decay. Over 800 bacterial isolates cultured from the macroalga were screened for the production of algal cell wall polysaccharidases and a range of species which displayed multiple hydrolytic enzyme activities were identified. Extracts from these enzyme-active bacterial isolates were then used in EAE of phenolics from Fucus vesiculosus and were shown to be more efficient than commercial enzyme preparations in their extraction efficiencies.


Assuntos
Ascophyllum/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Fracionamento Químico/métodos , Polissacarídeo-Liase/biossíntese , Polissacarídeo-Liase/química , Bactérias/enzimologia , Bactérias/isolamento & purificação , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Fucus/química , Hidrólise , Microbiota , Fenóis/isolamento & purificação , Polissacarídeo-Liase/isolamento & purificação , Proteólise , Alga Marinha/microbiologia
19.
Bull Exp Biol Med ; 166(6): 766-769, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31028586

RESUMO

The effect of sulfated polysaccharide from brown alga Fucus evanescens (fucoidan) administered via different routes (peroral and parenteral) on the dynamic of some lipid metabolism parameters and markers of systemic inflammation in mice with experimental dyslipidemia induced by prolonged administration of poloxamer P-407. It was found that fucoidan corrected the main parameters of lipid metabolism, reduced the level of endothelial dysfunction marker endothelin-1 and proinflammatory cytokines TNFα, IFNγ in blood serum in animals with experimental dyslipidemia. These findings open prospects for using fucoidan in the complex treatment of metabolic disorders and atherosclerotic inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Dislipidemias/tratamento farmacológico , Fucus/química , Regulação da Expressão Gênica/efeitos dos fármacos , Polissacarídeos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Dislipidemias/induzido quimicamente , Dislipidemias/genética , Dislipidemias/imunologia , Endotelina-1/genética , Endotelina-1/imunologia , Inflamação/prevenção & controle , Interferon gama/genética , Interferon gama/imunologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Poloxâmero/administração & dosagem , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
20.
Mar Drugs ; 17(3)2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30857204

RESUMO

Phlorotannins are phloroglucinol-based phenolic compounds, occurring particularly in brown macroalgae, that have been recognized for their promising bioactive properties. In this study, the extraction of phlorotannins from Fucus vesiculosus was evaluated with particular emphasis on the influential parameters, including the solvent concentration, solvent-solid ratio, extraction temperature and extraction time, using a single-factor design followed by a Box-Behnken design. The maximum total phlorotannin content, determined using the 2,4-dimethoxybenzaldehyde (DMBA) method, corresponded to 2.92 ± 0.05 mg of phloroglucinol equivalents/g dry seaweed (mg PGE/g DS), and was achieved for extracts carried out with acetone 67% (v/v), a solvent-solid ratio of 70 mL/g and temperature at 25 °C. This crude extract, together with a semi-purified phlorotannin fraction, were further evaluated for their anti-enzymatic capacity against α-glucosidase, α-amylase and pancreatic lipase, both showing promising inhibitory effects, particularly against α-glucosidase for which a greater inhibitory effect was observed compared to the pharmaceutical drug acarbose (IC50 = 4.5 ± 0.8 and 0.82 ± 0.3 µg/mL, respectively, against 206.6 ± 25.1 µg/mL). Additionally, the ultra-high-pressure liquid chromatography coupled to mass spectrometry (UHPLC-MS) analysis carried out on the ethyl acetate fraction revealed the presence of fucols, fucophlorethols, fuhalols and several other phlorotannin derivatives. Moreover, possible new phlorotannin compounds, including fucofurodiphlorethol, fucofurotriphlorethol and fucofuropentaphlorethol, have been tentatively identified in this extract. Overall, this study provides evidence that F. vesiculosus phlorotannin-rich extracts hold potential for the management of the activity of α-glucosidase, α-amylase and pancreatic lipase, which are well known to be linked to metabolic disorders such as diabetes and obesity.


Assuntos
Inibidores Enzimáticos/farmacologia , Fucus/química , Extratos Vegetais/farmacologia , Alga Marinha/química , Taninos/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/uso terapêutico , Lipase/antagonistas & inibidores , Lipase/metabolismo , Espectrometria de Massas , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo , Floroglucinol/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Taninos/química , Taninos/isolamento & purificação , Taninos/uso terapêutico , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
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