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1.
Mar Drugs ; 16(6)2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29867001

RESUMO

Fucus vesiculosus is a brown seaweed used in the treatment of obesity. This seaweed synthesizes various bioactive molecules, one of them being a sulfated polysaccharide known as fucoidan (FF). This polymer can easily be found commercially, and has antiadipogenic and lipolytic activity. Using differential precipitation with acetone, we obtained four fucoidan-rich fractions (F0.5/F0.9/F1.1/F2.0) from FF. These fractions contain different proportions of fucose:glucuronic acid:galactose:xylose:sulfate, and also showed different electrophoretic mobility and antioxidant activity. Using 3T3-L1 adipocytes, we found that all samples had lipolytic action, especially F2.0, which tripled the amount of glycerol in the cellular medium. Moreover, we observed that FF, F1.0, and F2.0 have antiadipogenic activity, as they inhibited the oil red staining by cells at 40%, 40%, and 50%, respectively. In addition, they decreased the expression of key proteins of adipogenic differentiation (C/EBPα, C/EBPß, and PPARγ). However, F0.5 and F0.9 stimulated the oil red staining at 80% and increased the expression of these proteins. Therefore, these fucoidan fractions have an adipogenic effect. Overall, the data show that F2.0 has great potential to be used as an agent against obesity as it displays better antioxidant, lipolytic and antiadipogenic activities than the other fucoidan fractions that we tested.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Fucus/química , Polissacarídeos/farmacologia , Células 3T3 , Animais , Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Fucose/farmacologia , Galactose/farmacologia , Camundongos , PPAR gama/metabolismo , Alga Marinha/química , Sulfatos/farmacologia , Xilose/farmacologia
2.
Int J Mol Sci ; 18(11)2017 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-29137120

RESUMO

Scorpions of the genus Tityus are responsible for the majority of envenomation in Brazil, the Tityus serrulatus species being the most common and dangerous in South America. In this approach, we have investigated the ability of the aqueous extract from the leaves of Aspidosperma pyrifolium in reducing carrageenan-induced inflammation and the inflammation induced by T. serrulatus envenomation in mice. We also evaluated the cytotoxic effects of this extract, using the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl-2H-tetrazolium (MTT) assay and the results revealed that the extract is safe. Analysis by High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC-DAD) and Liquid Chromatography Coupled with Mass Spectrometry with Diode Array Detection (LC-DAD-MS) showed one major chemical component, the flavonoid rutin and phenolics compounds. For in vivo studies in carrageenan-induced peritonitis model, mice received extracts, dexamethasone, rutin or saline, before administration of carrageenan. For venom-induced inflammation model, animals received T. serrulatus venom and were, simultaneously, treated with extracts, antivenom, rutin or saline. The extract and rutin showed a reduction in the cell migration into the peritoneal cavity, and in the same way the envenomated animals also showed reduction of edema, inflammatory cell infiltration and vasodilation in lungs. This is an original study revealing the potential action of A. pyrifolium against inflammation caused by Tityus serrulatus venom and carrageenan, revealing that this extract and its bioactive molecules, specifically rutin, may present potential anti-inflammatory application.


Assuntos
Anti-Inflamatórios/uso terapêutico , Aspidosperma/química , Peritonite/induzido quimicamente , Peritonite/tratamento farmacológico , Células 3T3 , Animais , Anti-Inflamatórios/farmacologia , Carragenina , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Inflamação/complicações , Inflamação/tratamento farmacológico , Inflamação/patologia , Cinética , Pulmão/efeitos dos fármacos , Pulmão/patologia , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Peritonite/complicações , Peritonite/patologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Rutina/farmacologia , Venenos de Escorpião , Fatores de Tempo
3.
Molecules ; 22(6)2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28604636

RESUMO

Baccharis trimera (Less.) DC (gorse) is a plant popularly used for the treatment of obesity. In this study, we prepared three B. trimera extracts aqueous extract (AE), decoction (AE-D), and methanol extract (ME) and investigated their antioxidant effects in six different tests and their anti-adipogenic effect in 3T3-L1 cells. The extracts showed a dose-dependent antioxidant activity in all tests. AE was the most potent antioxidant in copper and ferric ion chelation assays, whereas AE-D was the most potent in superoxide and hydroxyl radical scavenging assays, reducing power assay, and total antioxidant capacity analysis. Only ME showed a cytotoxic effect against 3T3-L1 cells. Lipid accumulation decreased in 3T3-L1 adipocytes in the presence of AE and AE-D extracts (0.5 to 1.0 mg/mL). In addition, the extracts dramatically attenuated the levels of adipogenic transcriptional factors, including CCAAT enhancer-binding protein α (C/EBPα), CCAAT enhancer-binding protein ß (C/EBPß), and gamma receptors by peroxisome proliferators (PPARγ), during adipogenesis. AE-D (1.0 mg/mL) caused an approximately 90% reduction in the levels of these molecules. We propose that B. trimera has an anti-adipogenic effect and could be used in the development of functional foods.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/genética , Obesidade/tratamento farmacológico , PPAR gama/genética , Extratos Vegetais/administração & dosagem , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia/efeitos dos fármacos , Animais , Antioxidantes/química , Baccharis/química , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Obesidade/genética , Obesidade/patologia , Extratos Vegetais/química
4.
J Ethnopharmacol ; 153(3): 890-5, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24704487

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Envenoming caused by scorpion sting is a serious public health problem. In Brazil, 13,038 accidents caused by venomous animals have been reported. Of this total, 53% of the cases and 14 deaths were caused by scorpions. Furthermore, Tityus serrulatus (Buthidae) is the most dangerous scorpion due to the high toxicity of its venom. The treatment is the common supportive therapy and the serum therapy, but some people do not have access to both therapies and seek healing through the use of medical plants. AIM OF THE STUDY: This study evaluated the ability of the crude extract and fractions from the leaves of Ipomoea asarifolia in neutralizing the main biological effects caused by Tityus serrulatus envenoming in mice. MATERIALS AND METHODS: BALB/c mice were pretreated (i.v.) with 100 µλ of aqueous extracts and fractions dichloromethane, ethyl acetate, and n-butanol (CH2Cl2, EtOAc, and n-BuOH, respectively) of Ipomoea asarifolia, rutin or saline. Then, the animals received 100 µλ (i.p.) of venom of Tityus serrulatus (0.8 mg/kg). After six hours, the peritoneal lavage was performed with PBS and the number cells were determined using a Neubauer chamber. The supernatants were collected for determination of cytokines, such as IL-6, IL-12, and IL-1ß. RESULTS: The aqueous extract, fractions and rutin, at all doses, significantly reduced cell migration, which was endorsed by the reduction of the levels of certain cytokines. CONCLUSION: This is the first study that demonstrated the potential effect of Ipomoea asarifolia against inflammation caused by Tityus serrulatus venom, suggesting that these extracts and/or their bioactive molecules, especially the flavonoid rutin, have potential use in the therapy of this envenomation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antídotos/uso terapêutico , Ipomoea , Extratos Vegetais/uso terapêutico , Rutina/uso terapêutico , Venenos de Escorpião/toxicidade , Células 3T3 , Animais , Anti-Inflamatórios/farmacologia , Antídotos/farmacologia , Movimento Celular/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fitoterapia , Extratos Vegetais/farmacologia , Folhas de Planta , Rutina/farmacologia , Escorpiões
5.
Lasers Med Sci ; 29(4): 1385-95, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24526326

RESUMO

Low-level laser therapy (LLLT) has been shown to be effective in promoting cell proliferation. There is speculation that the biostimulatory effect of LLLT causes undesirable enhancement of tumor growth in neoplastic diseases since malignant cells are more susceptible to proliferative stimuli. This study evaluated the effects of LLLT on proliferation, invasion, and expression of cyclin D1, E-cadherin, ß-catenin, and MMP-9 in a tongue squamous carcinoma cell line (SCC25). Cells were irradiated with a diode laser (660 nm) using two energy densities (0.5 and 1.0 J/cm(2)). The proliferative potential was assessed by cell growth curves and cell cycle analysis, whereas the invasion of cells was evaluated using a Matrigel cell invasion assay. Expression of cyclin D1, E-cadherin, ß-catenin, and MMP-9 was analyzed by immunofluorescence and flow cytometry and associated with the biological activities studied. LLLT induced significantly the proliferation of SCC25 cells at 1.0 J/cm(2), which was accomplished by an increase in the expression of cyclin D1 and nuclear ß-catenin. At 1.0 J/cm(2), LLLT significantly reduced E-cadherin and induced MMP-9 expression, promoting SCC25 invasion. The results of this study demonstrated that LLLT exerts a stimulatory effect on proliferation and invasion of SCC25 cells, which was associated with alterations on expression of proteins studied.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Terapia com Luz de Baixa Intensidade , Neoplasias Bucais/patologia , Neoplasias Bucais/radioterapia , Caderinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Ciclina D1/metabolismo , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Bucais/metabolismo , Invasividade Neoplásica , beta Catenina/metabolismo
6.
Carbohydr Polym ; 98(1): 224-32, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23987339

RESUMO

Fucan is a term used to denominate sulfated L-fucose rich polysaccharides. Here, a heterofucan, named fucan B, was extracted from the Spatoglossum schröederi seaweed. This 21.5 kDa galactofucan inhibited CHO-K1 proliferation and migration when fibronectin was the substrate. Fucan B derivatives revealed that such effects depend on their degree of sulfation. Fucan B did not induce cell death, but promoted G1 cell cycle arrest. Western blotting and flow cytometry analysis suggest that fucan B binds to fibronectin and activates integrin, mainly integrin α5ß1, which induces FAK/RAS/MEK/ERK activation. FAK activation inhibits CHO-K1 migration on fibronectin and ERK blocks cell cycle progression. This study indicates that fucan B could be applied in developing new antitumor drugs.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Antineoplásicos/metabolismo , Células CHO , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cricetinae , Cricetulus , Descoberta de Drogas , Ativação Enzimática/efeitos dos fármacos , Fibronectinas/metabolismo , Fucose/química , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Polissacarídeos/metabolismo
7.
World J Microbiol Biotechnol ; 28(3): 1097-105, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22805831

RESUMO

Chitooligosaccharides (COS) are partially hydrolyzed compounds derived from chitosan that exhibit a number of biological activities, including antitumor, antibacterial and antifungal properties. In this work, we examined the cytotoxicity of pure COS and oligomers A, B and C (solutions composed of different amounts of COS) produced by enzymatic hydrolysis using a crude enzyme extract produced by the fungus Metarhrizium anisopliae. The antiproliferative effect of these molecules was analyzed using tumor cell lines (HepG2 and HeLa cells) and in a normal cell line (3T3). The antioxidant activity was analyzed in several in vitro experiments. Glucosamine showed higher toxicity (approximately 92%) to all cell lines studied. However, the oligomers obtained after hydrolysis demonstrated no toxic effects on the normal cells (3T3). Furthermore, we showed that a small amount of other COS can decrease the cytotoxic effect of glucosamine against 3T3 cells, indicating that glucosamine could be used as an antitumor drug in the presence of other COS. In addition, different effects were found in antiproliferative assays, which depended on the COS composition in the oligomers (A, B and C), showing that a combination of them may be essential for developing antineoplastic drugs. Superoxide anion scavenging was the main antioxidant activity demonstrated by the COS and oligomers. This activity was also dependent on the oligomer composition of the chitosan hydrolysates. Further work will identify the ideal proportions of COS and glucosamine for maximizing the effects of these biological activities.


Assuntos
Quitosana/metabolismo , Glucosamina/antagonistas & inibidores , Glucosamina/toxicidade , Oligossacarídeos/metabolismo , Animais , Antioxidantes/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Metarhizium/enzimologia , Camundongos
8.
Mar Drugs ; 9(6): 952-966, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21747741

RESUMO

Fucan is a term used to denominate a type of polysaccharide which contains substantial percentages of l-fucose and sulfate ester groups. We obtained five heterofucans from Sargassum filipendula by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucose, glucuronic acid, galactose and sulfate. These fucans did not show anticoagulant activity in PT and aPTT tests. Their antioxidant activity was evaluated using the follow tests; total antioxidant capacity, scavenging hydroxyl and superoxide radicals, reducing power and ferrous ion [Fe(II)] chelating. All heterofucans displayed considerable activity, especially SF-1.0v which showed the most significant antioxidant potential with 90.7 ascorbic acid equivalents in a total antioxidant capacity test and similar activity when compared with vitamin C in a reducing power assay. The fucan antiproliferative activity was performed with HeLa, PC3 and HepG2 cells using MTT test. In all tested conditions the heterofucans exhibited a dose-dependent effect. The strongest inhibition was observed in HeLa cells, where SF-1.0 and SF-1.5 exhibited considerable activity with an IC50 value of 15.69 and 13.83 µM, respectively. These results clearly indicate the beneficial effect of S. filipendula polysaccharides as antiproliferative and antioxidant. Further purification steps and additional studies on structural features as well as in vivo experiments are needed to test the viability of their use as therapeutic agents.


Assuntos
Antioxidantes/química , Proliferação de Células/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/farmacologia , Sargassum/química , Alga Marinha/química , Anticoagulantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Fucose/química , Galactose/química , Glucose/química , Ácido Glucurônico/química , Células HeLa , Células Hep G2 , Humanos , Tempo de Tromboplastina Parcial/métodos , Sulfatos/química
9.
Int J Mol Sci ; 12(5): 3352-65, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21686189

RESUMO

In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula 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. 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.


Assuntos
Anticoagulantes , Antineoplásicos Fitogênicos , Antioxidantes , Extratos Vegetais , Alga Marinha/química , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Furanos/química , Furanos/isolamento & purificação , Furanos/farmacologia , Células HeLa , Humanos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
10.
Mar Biotechnol (NY) ; 13(1): 41-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20333426

RESUMO

Ploidy manipulation has been rarely used in the genetic improvement of cultured marine shrimps. Although polyploid induction has been proven to be successful in Penaeids, including the species Litopenaeus vannamei, the methodology still requires some improvements. In the present work, different thermal shock treatments on ploidy manipulation were tested and a protocol for detecting polyploid individuals was also established. Fertilized eggs were treated by cold (10°C) and heat (38°C) thermal shocks for 8, 12, 15, 18, 20, and 22 min to induce polyploidy. Nuclear measurements within distinct treatments revealed a significant deviation in relation to the mean diameter of nuclei in the control individuals. Triploid and tetraploid metaphases were observed within treated individuals, confirming the increase of interphasic nuclear diameter. The cold thermal shock was more efficient than the hot ones, besides leading to a higher and more homogeneous hatchery rate. A mean number of three nucleoli per nucleus were observed in diploid individuals, while treated samples usually presented up to five nucleoli per nucleus. The standardization of protocols to obtain and detect polyploid products allows further utilization of such methods on a commercial scale in order to evaluate the performance of polyploid individuals in the genetic improvement of L. vannamei.


Assuntos
Penaeidae/genética , Poliploidia , Adaptação Fisiológica/genética , Animais , Aquicultura/métodos , Temperatura Baixa , Análise Citogenética/métodos , Temperatura Alta , Penaeidae/embriologia , Ploidias , Estresse Fisiológico
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