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1.
Int J Mol Sci ; 21(7)2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276415

RESUMO

Numerous studies highlighted the beneficial effects of the Mediterranean diet (MD) in maintaining health, especially during ageing. Even neurodegeneration, which is part of the natural ageing process, as well as the foundation of ageing-related neurodegenerative disorders like Alzheimer's and Parkinson's disease (PD), was successfully targeted by MD. In this regard, olive oil and its polyphenolic constituents have received increasing attention in the last years. Thus, this study focuses on two main olive oil polyphenols, hydroxytyrosol (HT) and oleuropein aglycone (OLE), and their effects on ageing symptoms with special attention to PD. In order to avoid long-lasting, expensive, and ethically controversial experiments, the established invertebrate model organism Caenorhabditis elegans was used to test HT and OLE treatments. Interestingly, both polyphenols were able to increase the survival after heat stress, but only HT could prolong the lifespan in unstressed conditions. Furthermore, in aged worms, HT and OLE caused improvements of locomotive behavior and the attenuation of autofluorescence as a marker for ageing. In addition, by using three different C. elegans PD models, HT and OLE were shown i) to enhance locomotion in worms suffering from α-synuclein-expression in muscles or rotenone exposure, ii) to reduce α-synuclein accumulation in muscles cells, and iii) to prevent neurodegeneration in α-synuclein-containing dopaminergic neurons. Hormesis, antioxidative capacities and an activity-boost of the proteasome & phase II detoxifying enzymes are discussed as potential underlying causes for these beneficial effects. Further biological and medical trials are indicated to assess the full potential of HT and OLE and to uncover their mode of action.


Assuntos
Acetatos/uso terapêutico , Monoterpenos Ciclopentânicos/uso terapêutico , Neurônios Dopaminérgicos/metabolismo , Doença de Parkinson/prevenção & controle , Álcool Feniletílico/análogos & derivados , Piranos/uso terapêutico , alfa-Sinucleína , Acetatos/farmacologia , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/efeitos dos fármacos , Monoterpenos Ciclopentânicos/farmacologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/fisiologia , Álcool Feniletílico/farmacologia , Álcool Feniletílico/uso terapêutico , Polifenóis/farmacologia , Piranos/farmacologia , Resultado do Tratamento
2.
Anticancer Res ; 40(4): 2025-2032, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234893

RESUMO

BACKGROUND/AIM: The winemaking procedure results in the generation of stems, a by-product that is harmful to the environment. Concomitantly, stems are rich in polyphenols and, hence, they are putatively beneficial for human health. MATERIALS AND METHODS: In this study, the grape stem extracts derived from three native Greek vine varieties, namely Mavrodaphne, Muscat and Rhoditis were examined for their chemical composition and antioxidant and antimutagenic properties using a battery of in vitro biomarkers. RESULTS: All extracts are rich in polyphenols. Moreover, they exhibit potent antioxidant and antimutagenic properties with the extract of Mavrodaphne being the strongest in reducing the DPPH• and O2 -• radicals and the Fe3+ and in protecting plasmid DNA from peroxyl radical-induced oxidative modification. CONCLUSION: Therefore, although they are serious pollutants, grape stems contain phytochemicals with important biological properties and can be used as (ingredients of) bio-functional foods to improve certain aspects of human health.


Assuntos
Antioxidantes/farmacologia , DNA/efeitos dos fármacos , Polifenóis/farmacologia , Vitis/química , DNA/metabolismo , Dano ao DNA/efeitos dos fármacos , Grécia , Humanos , Oxirredução , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Caules de Planta/química , Plasmídeos/efeitos dos fármacos , Plasmídeos/metabolismo , Polifenóis/química , Espécies Reativas de Oxigênio/metabolismo
3.
Mutat Res ; 852: 503168, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32265044

RESUMO

A large number of species belonging to the genus Teucrium are used in pharmacy and traditional medicine for the treatment of different diseases. This study aimed to evaluate the polyphenolic composition as well as genotoxic and cytotoxic effects of methanolic extracts from T. arduini and T. flavum, two native species found in Montenegro. We determined the total phenolic and flavonoid contents of these plants using spectrophotometric methods; the qualitative content of polyphenolic compounds was investigated by high-performance liquid chromatography (HPLC). Genotoxicity in cultured human lymphocytes was measured in the cytokinesis-block micronucleus assay (CBMN) and comet assay in the range between 125 and 1000 µg/mL. Cytotoxicity was assessed by the MTT viability assay in normal human MRC-5 fibroblasts and MDA-MB-231 breast carcinoma cells. The content of total phenolics and flavonoids in T. arduini extract was higher than in T. flavum (200.35 mg GA/g vs. 171.08 mg GA/g; 96.32 mg RU/g vs. 78.14 mg RU/g). The polyphenolic composition of both extracts was qualitatively similar and eight phenol compounds were identified. The most commonly present phenol was caffeic acid and among four flavonoids, the most common was quercetin. Both plant extracts were genotoxic in both the CBMN and comet assays at concentrations of 250, 500 and 1000 µg/mL. After 72 h of exposure, the extracts of T. arduini and T. flavum were found to induce cytotoxicity in MRC-5 fibroblasts but not in MDA-MB-231 breast cancer cells. The results suggest that the constituents of both plant species are genotoxic and cytotoxic, therefore these extracts warrant additional evaluation to be safely applied in humans.


Assuntos
Flavonoides/toxicidade , Mutagênicos/toxicidade , Polifenóis/toxicidade , Teucrium/química , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Flavonoides/isolamento & purificação , Humanos , Metanol/química , Testes para Micronúcleos , Montenegro , Mutagênicos/isolamento & purificação , Especificidade de Órgãos , Extratos Vegetais/química , Plantas Medicinais , Polifenóis/isolamento & purificação , Solventes/química
4.
Chemosphere ; 250: 126267, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32114344

RESUMO

Biological methods for the removal of hexavalent chromium (Cr(VI)) from contaminated sites are safe and efficient. This is especially true because they employ microorganisms and nutrients. The use of appropriate nutrients is important for the methods to be economically feasible. This paper aims to investigate the role of polyphenol from sugarcane molasses, an inexpensive material derived from the waste of the sugar industry, as a nutrient that efficiently provides carbon for Cr(VI)-removing bacteria. The colored constituents of sugarcane molasses were characterized based on the activity of Cr(VI)-reduction and the support of bacterial growth. Molasses promoted Cr(VI)-reducing activity in a pH dependent manner. The activity was related to the colored constituents, excluding sugar, by using absorbent-column chromatography. Moreover, the activity was closely related to the polyphenol fractions, which were slightly different from those of the colored constituents. Unlike the colored constituents, the isolated sugar was sufficient to support the growth of bacteria. Polyphenols from sugarcane molasses could reduce Cr(VI) with no effect on bacterial growth. The removal of Cr(VI) combining molasses and Cr(VI)-reducing bacteria may present an additive and/or synergistic effect.


Assuntos
Biodegradação Ambiental , Cromo/química , Polifenóis/química , Bactérias/metabolismo , Carbono , Melaço , Nutrientes , Oxirredução , Saccharum
5.
J Int Soc Sports Nutr ; 17(1): 15, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143716

RESUMO

BACKGROUND: Maximal strength-speed exercise is a powerful stimulus to acutely increase concentrations of circulating steroid hormones and homocysteine [Hcy]. There is some evidence that antioxidant beverages rich in polyphenols can attenuate [Hcy] levels and modulate endocrine responses in favor of an anabolic environment. Polyphenols-rich pomegranate (POM) have been reported to possess one of the highest antioxidant capacities compared to other purported nutraceuticals and other food stuffs. Studies focused on proving the beneficial effect of POM consumption during maximal strength exercises have only measured physical performance, muscle damage, oxidative stress and inflammatory responses, while POM effects on [Hcy] and hormonal adaptations are lacking. The aim of the present study was to investigate the effect of consuming natural polyphenol-rich pomegranate juice (POMj) on the acute and delayed [Hcy] and steroidal hormonal responses to a weightlifting exercises session. METHODS: Nine elite weightlifters (21.0 ± 1 years) performed two Olympic-weightlifting sessions after ingesting either the placebo (PLA) or POMj supplements. Venous blood samples were collected at rest and 3 min and 48 h after each session. RESULTS: Compared to baseline values, circulating cortisol [C] decreased (p < 0.01) and testosterone/cortisol [T/C] ratio increased immediately following the training session in both PLA and POMj conditions (p = 0.003 for PLA and p = 0.02 for POM). During the 48 h recovery period, all tested parameters were shown to recover to baseline values in both conditions with significant increases in [C] and decreases in [T/C] (p < 0.01 for PLA and p < 0.05 for POMj) from 3 min to 48 h post-exercises. Compared to PLA, a lower level of plasma testosterone [T] was registered 3 min post exercise using POMj supplementation (p = 0.012) and a significant decrease (p = 0.04, %change = - 14%) in plasma [Hcy] was registered during the 48 h recovery period only using POMj. A moderate correlation was observed between [Hcy] and [T] responses (p = 0.002, r = - 0.50). CONCLUSION: In conclusion, supplementation with POMj has the potential to attenuate the acute plasma [T] response, but did not effect 48 h recovery kinetics of [Hcy] following weightlifting exercise. Further studies investigating androgen levels in both plasma and muscular tissue are needed to resolve the functional consequences of the observed acute POMj effect on plasma [T]. TRIAL REGISTRATION: Clinical Trials.gov, ID: NCT02697903. Registered 03 March 2016.


Assuntos
Sucos de Frutas e Vegetais , Homocisteína/sangue , Hidrocortisona/sangue , Polifenóis/administração & dosagem , Romã (Fruta) , Testosterona/sangue , Levantamento de Peso/fisiologia , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Adulto Jovem
6.
Bioresour Technol ; 305: 123130, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32173260

RESUMO

In this study, three types of biomass were first pretreated with an aqueous phase bio-oil instead of traditional acid washing. Then, the washed samples were pretreated with drying (100 â„ƒ, 30 min) and torrefaction (250 â„ƒ, 30 min) using a parabolic-trough solar receiver system. The subsequent pyrolysis was performed at 550 â„ƒ for 10 min using a parabolic-dish solar receiver system. Results showed that the solar energy can effectively ensure the temperature required for biomass drying, torrefaction, and pyrolysis, having thus a potential to replace the conventional electric heating or fossil fuel heating. Such a strategy combines the advantages of the independent pretreatments, i.e., leaching out of metallic species and reduction of oxygen content. Consequently, the high heating value of bio-oil increased remarkably, the generation of acids was strongly inhibited, whereas the formation of phenols and anhydrosugars was promoted. Therefore, the method proposed herein is promising for upgrading of biomass and bio-oil.


Assuntos
Temperatura Alta , Pirólise , Biocombustíveis , Biomassa , Óleos Vegetais , Polifenóis
7.
J Environ Manage ; 261: 110226, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148296

RESUMO

Dye decolorization is of crucial concern for effectively treating dye wastewater. In this study, rapid and effective decolorization of malachite green cationic dye was achieved by tea polyphenols and ferric ions under moderate conditions. Approximately 96.2% of decolorization efficiency could be obtained within the first 10 min at the initial dye concentration of 50 mg/L. The proposed method can perform excellently in a wide pH range of 5-9 and decolorization kinetics of malachite green under different solution pH were well fitted by the pseudo-second-order model. After the decolorization, only a slight reduction of tea polyphenols was observed, while the strength of peaks assigned to nitrogen-containing groups was significantly weakened, indicating that the N-demethylation reaction might occur during the decolorization process. The nucleophilic attack of deprotonated hydroxyl groups of tea polyphenols was proposed as the decolorization mechanism. The presence of ferric ions at an appropriate dosage could promote the deprotonation process and therefore enhance decolorization efficiency, while excess ferric ions in solution might compete with malachite green dye towards reductive sites on tea polyphenols. The findings from this study provided an economical and environmentally friendly technique for the effective decolorization of dye wastewater.


Assuntos
Polifenóis , Corantes de Rosanilina , Corantes , Concentração de Íons de Hidrogênio , Íons , Chá
8.
Food Chem ; 317: 126415, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087518

RESUMO

This paper focused on improving antityrosinase ability of quercetin, cinnamic acid, and ferulic acid (named Q-CA-FA) from Asparagus by combining heating with ultrasound treatments. Fluorescence spectroscopy and UPLC-MS were used to evaluate inhibitory mechanisms. Results showed that the impacts of combining heating (150 °C for 30 min) with ultrasound (600 W for 30 min) treatments were similar to heating treatment (150 °C for 120 min) alone, and the inhibition rate could reach 98.2% in the addition of 5 mM Q-CA-FA. Fluorescence quenching indicated that treated Q-CA-FA-tyrosinase complex was more stable, but combining treatments did not change the major force between tyrosinase and polyphenols. Thermodynamic analysis illustrated that the randomness of compounds was also increased. Interestingly, 2-hydroxy-3-(3-hydroxy-4-methoxy-phenyl)-propionic acid 4-(2,3-dihydroxy-propyl)-phenyl ester was newly detected, which might be the major reason for enhancing antityrosinase ability. Taken together, these results provide a creative insight on increasing antityrosinase activity by combining heating with ultrasound treatments.


Assuntos
Monofenol Mono-Oxigenase/metabolismo , Polifenóis/metabolismo , Sonicação , Asparagus (Planta)/química , Asparagus (Planta)/metabolismo , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Cinamatos/metabolismo , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Temperatura Alta , Monofenol Mono-Oxigenase/antagonistas & inibidores , Polifenóis/análise , Quercetina/análise , Quercetina/metabolismo , Espectrometria de Fluorescência , Espectrometria de Massas em Tandem , Termodinâmica
9.
Food Chem ; 317: 126423, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097824

RESUMO

The impact of pH (6-9) and NaCl concentration (0-0.5 mol.L-1) on sunflower protein extraction was studied through design of experiments. The considered criteria were protein extraction yield (total proteins, helianthinin and albumins), chlorogenic acids covalently bound to proteins, and free chlorogenic acid concentration in the aqueous extract. Statistical analysis showed that the obtained by design of experiments the polynomial models of each extraction criteria were reliable for predicting the responses. They were employed in an original multi-objective optimization methodology. The optimal conditions revealed to be pH 7.3/0.3 mol.L-1 NaCl yielded 46.83% and 59.16% of total protein and albumin extraction yield, 1.730 and 1.998 mg.g-1 of chlorogenic acids covalently bound to helianthinin and albumins in aqueous extract, respectively. The sunflower protein isolate obtained after extraction in this condition had good solubility (40-80% at pH 5-8), functional properties (foaming and emulsifying) and a satisfying color.


Assuntos
Helianthus/metabolismo , Extração Líquido-Líquido/métodos , Proteínas de Plantas/isolamento & purificação , Extração em Fase Sólida/métodos , Albuminas/análise , Albuminas/isolamento & purificação , Albuminas/metabolismo , Ácido Clorogênico/química , Ácido Clorogênico/metabolismo , Concentração de Íons de Hidrogênio , Isomerismo , Extração Líquido-Líquido/instrumentação , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Polifenóis/análise , Polifenóis/metabolismo , Ligação Proteica , Cloreto de Sódio/química , Extração em Fase Sólida/instrumentação
10.
Ecotoxicol Environ Saf ; 192: 110311, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061988

RESUMO

The uptake and accumulation of cadmium (Cd) in Salvia miltiorrhiza (Bge.) negatively affects the quality of its harvested roots, and seriously threatens human health. This study investigates the effect of a microbial inoculant (MI) and garbage enzyme (GE) on Cd uptake, the accumulation of bioactive compounds, and the community composition of microbes in the rhizosphere soil of S. miltiorrhiza under Cd stress. S. miltiorrhiza seedlings were transplanted to Cd-contaminated pots and irrigated with an MI, GE, a combination of an MI and GE (MIGE) or water (control). The results indicated that treatments with an MI, GE or MIGE can reduce Cd uptake in S. miltiorrhiza. The MIGE treatment had greater efficiency in reducing Cd uptake than the control (reduction by 37.90%), followed by the GE (25.31%) and MI (5.84%) treatments. Treatments with an MI, GE and MIGE had no significant impact on fresh and dry root biomass. Relative to the control, the MI treatment had the highest efficiency in increasing the accumulation of total tanshinones (an increase of 40.45%), followed by the GE treatment (40.08%), with the MIGE treatment (9.90%) treatment not having a more favorable effect than the separate application of an MI or GE. The salvianolic acid content for all groups was higher than the standard prescribed by Chinese pharmacopoeia, notwithstanding a slightly lower level in the treated groups relative to the control. In addition, metagenomic analysis indicated changes in the relative abundance of soil microbes associated with the bioremediation of heavy metals. The relative abundances of Brevundimonas, Microbacterium, Cupriavidus and Aspergillus were significantly greater in the treated groups than in the Control. These results suggest that using MI and GE, either separately or together, may not only improve the quality of S. miltiorrhiza but may also facilitate the microbial remediation of soil contaminated with Cd.


Assuntos
Cádmio/toxicidade , Salvia miltiorrhiza/efeitos dos fármacos , Salvia miltiorrhiza/metabolismo , Poluentes do Solo/toxicidade , Abietanos/metabolismo , Alcenos/análise , Biodegradação Ambiental , Biomassa , Cádmio/farmacocinética , Raízes de Plantas/efeitos dos fármacos , Polifenóis/análise , Rizosfera , Salvia miltiorrhiza/química , Microbiologia do Solo
11.
Chemosphere ; 250: 126236, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32088617

RESUMO

While polyphenol-based coating has been regarded as a promising alternative to functionalize membrane surface, it usually suffers from problems of low-efficient procedure and low utilization rate of the polyphenolic compounds, hindering its large-scale implementations. To solve these problems, this study provided a first report on inkjet printing of polyphenols (catechol (CA) or tannic acid (TA)) and sodium periodate (SP) on a polyvinylidene fluoride (PVDF) membrane to improve membrane performance. A series of analyses showed the efficient formation of homogenous films on the PVDF membrane surface and the improvement of hydrophilicity by the inkjet printing technique. The PVDF membranes decorated with the optimized polyphenolic coating exhibited a promising oil/water separation efficiency (higher than 99%) with a high average water permeation flux of 5.2 times higher than that of the pristine membrane. Meanwhile, the modified membranes illustrated a good stability under acidic conditions (pH = 2-7). The novel method proposed in this study is facile, cost-saving and environment-friendly. The advantages of the proposed method and the modified membranes demonstrated the great significance of the proposed method in practical applications.


Assuntos
Membranas Artificiais , Polifenóis/química , Interações Hidrofóbicas e Hidrofílicas , Polivinil , Impressão Tridimensional , Purificação da Água/métodos
12.
PLoS One ; 15(2): e0227996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084133

RESUMO

Jujube (Ziziphus lotus L.) fruit has multiple functional properties and represents an interesting source of bioactive compounds. The purpose of this study was to improve the functionality and the sensory properties of sponge cake enriched with Z. lotus fruit. The polyphenols and flavonoids levels in the sponge cake and its antioxidant potential increased with the addition of 0-10 g of jujube powder/100 g of wheat flour. The crumb color parameters, L* and b*, decreased with the addition of jujube powder, whereas the a* value increased. In the texture analysis, addition of jujube powder resulted in an increase of the hardness and chewiness, but the springiness was reduced. The sensory evaluation showed that supplementation of jujube powder did not manifest any undesirable organoleptic response and showed satisfactory consumer acceptability. Overall, the addition at 5% jujube powder showed the finest sensory properties of the sponge cake.


Assuntos
Sensação/fisiologia , Lanches , Ziziphus/química , Antioxidantes/análise , Cor , Flavonoides/análise , Frutas/química , Humanos , Extratos Vegetais/química , Polifenóis/análise , Pós
13.
Bioresour Technol ; 302: 122843, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32006926

RESUMO

The composite catalysts were synthesized with SiC powder and ZSM-5 and were characterized by Brunauer-Emmett-Teller, X-ray diffraction, thermogravimetric analysis, pyridine-infrared spectroscopy, and scanning electron microscopy. The catalysts showed a high heating rate and excellent catalytic performance for pyrolysis vapors, and the product fractional distribution and chemical compositions of bio-oil in a tandem system (microwave pyrolysis and microwave ex-situ catalytic reforming) was examined. Experimental results confirmed the quality of bio-oil produced by the microwave-induced catalytic reforming was better than that product through electric heating. Additionally, 36.94 wt% of bio-oil was obtained using the catalyst with 20%ZSM-5/SiC under the following conditions: feed-to-catalyst ratio, 2:1; pyrolysis temperature, 550 °C; and catalytic temperature, 350 °C. The selectivities of hydrocarbons reached up to 75.88%. After five cycles, the activity of the regenerated composite catalyst was retained at 95% of the original catalyst.


Assuntos
Micro-Ondas , Soja , Biocombustíveis , Catálise , Calefação , Temperatura Alta , Óleos Vegetais , Polifenóis , Pirólise
14.
J Photochem Photobiol B ; 204: 111587, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32062387

RESUMO

Although the photothermal therapy (PTT) has achieved tremendous progress in the recent times, still it has to improve an extensive way to achieve the efficient targeted photothermal removal of the tumor cells. Owing to this requirement, we demonstrated a novel class of reduced graphene oxide based photothermal therapeutic agent for the ablation of lung cancer cells (A549). A single step bio facile fabrication of graphene nanosheets using Memecylon edule leaf extract intermediated reduction of Graphene Oxide (GO). This process does not include the utilization of any toxic or harmful reducing agents. The relative results of different characterizations of graphene oxide and Memecylon edule leaf extract RGO delivers a potential representation by excluding the groups containing oxygen from GO and consecutive stabilization of the developed RGO. The reduced GO functionalization with the oxidized polyphenols results in their stability by avoiding the aggregation. The poly phenol anchored Reduced Graphene Oxide (RGO) exhibited exceptional near-infrared (NIR) irradiation of the lung cancer cells directed in vitro to deliver cytotoxicity. In an area of restricted success in the treatment of cancer, the results of our translation can provide a path for designing targeted PTT agents and also responds to stimulus environment for the safe ablation of the devastating disease.


Assuntos
Grafite/química , Raios Infravermelhos , Nanoestruturas/química , Polifenóis/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cães , Química Verde , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Células Madin Darby de Rim Canino , Magnoliopsida/química , Magnoliopsida/metabolismo , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Fototerapia/métodos , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
15.
Ann Palliat Med ; 9(2): 331-338, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32008337

RESUMO

BACKGROUND: This study investigates the effect of epigallocatechin gallate (EGCG) from tea leaves on hyperuricemia and explores the underlying mechanisms in vitro and in vivo. METHODS: The effects of EGCG on proliferation of BRL 3A rat liver cells were evaluated by CCK8 and after stimulation by xanthine the uric acid and xanthine oxidase (XOD) levels were evaluated by a kit; In an in vivo experiment, rats were treated with oxonic acid potassium salt combined with ethylamine pyrimidine to induce high uric acid hematic disease (7 days), The serum uric acid levels and XOD levels were evaluated by a kit, The expressions of OTA1 and GLUT9 were detected by RT-qPCR and Immunohistochemical. RESULTS: EGCG had no effect on proliferation, and significantly reduced serum uric acid levels and inhibited XOD activity (P<0.05). The rat model exhibited a significant rise in blood uric acid levels (54.59 mg/dL), and EGCG significantly reduced the high level of serum uric acid and inhibited XOD activity in the serum and liver tissues (P<0.05). RT-PCR showed that EGCG significantly increased mOAT1 expression in the kidney tissues and reduced mGLUT9 expression (P<0.05). Immunohistochemical results showed that EGCG significantly increased OAT1 expression in the kidney tissues and decreased GLUT9 expression (P<0.05). CONCLUSIONS: These results demonstrate that EGCG has obvious anti-hyperuricemia effects in vitro and in vivo via the inhibition of XOD activity and GLUT9 expression and the promotion of OAT1 expression.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Polifenóis/farmacologia , Ácido Úrico/metabolismo , Xantina Oxidase/metabolismo , Animais , Catequina/metabolismo , Fígado/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos , Ratos Sprague-Dawley , Chá , Ácido Úrico/sangue
16.
Int. j. morphol ; 38(1): 135-139, Feb. 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1056411

RESUMO

La angiogénesis es el proceso por el cual se forman nuevos vasos sanguíneos a partir de otros ya existentes. Para que esto se lleve a cabo de forma correcta debe existir un balance entre los factores proangiogénicos y los factores antiangiogénicos dentro del microambiente tisular. Por otra parte, la existencia de productos químicos naturales como los polifenoles, que son capaces de adquirirse en la dieta, inducen a estos factores a intervenir en el proceso de angiogénesis. Se administraron los polifenoles en filtros de metilcelulosa sobre la membrana alantocoriónica de huevos White Leghorn, manteniendo el posterior desarrollo normal del feto. Se utilizaron 15 fetos de pollo fijados en formalina tamponada, a los cuales se extrajo el corazón. El procesamiento de las muestras de corazón se realizó a través de técnicas histológicas, histoquímicas e inmunohistoquímica. Finalmente se evaluó la presencia del VEGF y la capacidad de formar vasos sanguíneos bajo el tratamiento con los polifenoles. La inmunorreactividad fue cuantificada mediante Image J®. Los resultados indican que Ácido cafeico y Pinocembrina disminuyen la densidad microvascular y la expresión de VEGF en corazones de fetos de pollo tratados con estos polifenoles. Tanto el Ácido Cafeico como la Pinocembrina cumplen un rol inhibitorio en el proceso de angiogénesis fisiológica en corazón de pollo, pudiendo modular las vías de señalización mediadas por los VEGFR o modulando la disponibilidad de VEGF. Estos polifenoles podrían utilizarse para el estudio de otros tejidos asociados a angiogénesis patológica.


Angiogenesis is the process by which new blood vessels are formed from other existing ones. A balance between proangiogenic factors and anti-angiogenic factors within the microenvironment must exist for the process to be carried out correctly. Similarly, the existence of natural chemicals such as polyphenols, which are capable of being acquired in the diet, induce these factors in the angiogenic process. Polyphenols were administered in the methylcellulose filters on the of chorioallantoic membrane of White Leghorn eggs, maintaining the normal posterior development of the fetus. 15 chicken fetuses were fixed in buffered formalin, obtaining the hearts to histological processing, performing histological, histochemical and immunohistochemical techniques. VEGF levels and the ability of the blood vessels growing under the stimulation of the polyphenols were evaluated. Immunoreactivity was quantified by Image J. The results indicate that caffeic acid and pinocembrin decreased microvascular density and VEGF expression in hearts stimulated with these polyphenols. Both the caffeic and pinocembrin acids play an inhibitory role in the physiological angiogenesis process in the chicken heart, which decrease the microvascular density and could act by modulating the signaling pathways mediated by the VEGFR or by modulating the availability of VEGF. The use of these polyphenols could be useful in studies of other tissues associated with pathological angiogenesis.


Assuntos
Animais , Ácidos Cafeicos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Embrião de Galinha , Polifenóis/farmacologia
17.
Chemosphere ; 250: 126214, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32088615

RESUMO

In this study, in-situ Fenton oxidation was used for the de-complexation and degradation of tannin-Cr(III) complexes. Cr(III) can be oxidized into free Cr(VI) under the effect of ·OH and oxidation products of tannin can be used as reductant for Cr(VI) to establish a redox cycle of Cr(III)-Cr(VI)-Cr(III). Thus, it is crucial to investigate the interactions of Cr(III) with tannin derived oxidation products due to negligible accumulation of Cr(VI) during Fenton oxidation treatment. Here, sequential filtration/ultrafiltration was applied to reveal the distribution characteristics of TOC and Cr fractions during the oxidation of tannin-Cr(III). As the increase of colloidal size of tannic acid products, residual TOC and Cr mainly distribute in larger size range after the oxidation of tannin-Cr(III) which can be ascribed to re-complexation between oxidation products and Cr(III). Besides, analytical results indicate that carboxyl group and hydroxyl group in oxidation products may cause the re-complexation of Cr(III), resulting in the formation of highly conjugated materials containing Cr(III). It can be concluded that due attention should be paid to the efficient removal technology and mechanism for polymer-Cr complexes, as well as the oxidation intermediates in the role of conversion and removal of Cr species.


Assuntos
Cromo/química , Polifenóis/química , Modelos Químicos , Oxirredução , Taninos
18.
Chem Commun (Camb) ; 56(21): 3187-3190, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32068230

RESUMO

The isomers vescalagin and castalagin protect SH-SY5Y cells from Aß42-mediated death. This is achieved better by vescalagin due to the spatial organization of its OH group at the C1 position of the glycosidic chain, improving its capacity to remodel the secondary structure of toxic Aß42 oligomers.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Taninos Hidrolisáveis/farmacologia , Polifenóis/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/toxicidade , Morte Celular/efeitos dos fármacos , Humanos , Taninos Hidrolisáveis/química , Estrutura Molecular , Polifenóis/química , Polifenóis/toxicidade , Agregados Proteicos/efeitos dos fármacos , Estrutura Secundária de Proteína , Células Tumorais Cultivadas
19.
J Agric Food Chem ; 68(10): 2849-2860, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32027498

RESUMO

Dr. Ragai K. Ibrahim, Professor Emeritus at Concordia University, Montréal, Canada, passed away on the November 19, 2017 at the age of 88 years. Dr. Ibrahim dedicated his entire professional life to polyphenols and spent most of his academic career (1967-1997) at the Department of Biology of Concordia University in Montréal. He has been an active member of the Groupe Polyphénols since the beginning. This paper is a tribute to Dr. Ibrahim from some of his former students. An overview of the evolution of polyphenol research since the late 1950s and the outstanding contribution that Dr. Ibrahim had to this topic is given. The input of Dr. Ibrahim's research to the enzymology and genetics of polyphenol biosynthesis is discussed. Furthermore, the links between Dr. Ibrahim's work and some aspects of modern studies on the health benefits of polyphenols are presented.


Assuntos
Extratos Vegetais/biossíntese , Plantas/metabolismo , Polifenóis/biossíntese , Canadá , História do Século XX , História do Século XXI , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas/química , Polifenóis/química , Polifenóis/farmacologia
20.
Food Chem ; 315: 126277, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004983

RESUMO

This study reports the effects of seasonal variation on the total polyphenol and flavonoid content and the in vitro antioxidant activity of Secondatia floribunda A. DC. The extracts were prepared from the inner bark and heartwood of samples harvested in the 2015 to 2016. The total phenolic and flavonoid content was determined by specific qualitative tests. The in vitro antioxidant capacity was analyzed using the following tests: 1-1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2'-azinobis-3-ethylbenzenothiazoline-6-sulfonic acid (ABTS+), ferric reducing antioxidant power (FRAP) and iron (Fe2+) chelating activity. The total polyphenol and total flavonoid content varied over the harvest period. The DPPH and ABTS tests revealed that in the dry season had the most potent in vitro antioxidant activity, although the extracts obtained during the rainy season presented the higher Fe2+ chelating and Ferric reducing activities. In conclusion, the phenolic content and in vitro antioxidant activity are correlated, and both are influenced by seasonality.


Assuntos
Antioxidantes/análise , Apocynaceae/química , Polifenóis/análise , Flavonoides/química , Extratos Vegetais/química , Estações do Ano
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