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1.
Food Chem ; 303: 125380, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445175

RESUMO

Soybean Bowman-Birk trypsin inhibitor (BBTI), an antinutritional factor of soy products, could strongly inhibit the protein digestion. The inactivation effect and mechanism of BBTI induced by tea polyphenols (TPs) and its major components (EGCG and EGC), were investigated in this study using fluorescence, FTIR, CD spectroscopy, isothermal titration calorimetry (ITC) and molecular docking. EGCG and EGC interacted with BBTI via static quenching process and hydrophobic interaction, with binding constant (Ka) of 2.19 × 103 M-1 and 0.25 × 103 M-1 at 298 K, respectively. TPs, EGCG and EGC induced a transition of BBTI conformation from disorder to order. ITC analysis and molecular docking revealed the interaction of EGCG-BBTI and EGC-BBTI were spontaneous, and hydrophobic interactions and hydrogen bonds were the predominant forces. Overall, this study clearly suggested that EGCG could be a promising inactivating agent for BBTI, which could also improve the safety and nutritional value of soy products.


Assuntos
Catequina/análogos & derivados , Simulação de Acoplamento Molecular , Inibidor da Tripsina de Soja de Bowman-Birk/química , Catequina/química , Catequina/farmacologia , Fluorescência , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica , Termodinâmica , Inibidor da Tripsina de Soja de Bowman-Birk/efeitos dos fármacos , Inibidor da Tripsina de Soja de Bowman-Birk/metabolismo
2.
Cell Biochem Biophys ; 77(4): 367-377, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31659617

RESUMO

Cisplatin is a widely used anti-cancer drug. However, cisplatin is limited in clinical treatment because of its severe nephrotoxicity. This study reported whether O-GSP can antagonize the cisplatin-induced cytotoxicity in HEK293 cells through inducing HO-1 protein expression. We previously demonstrated O-GSP can increase the survival rate of HEK293 and have protective effect on HEK293 cells. Herein, We found that O-GSP can antagonize cisplatin nephrotoxicity through regulating the expression of HO-1. O-GSP promotes the translocation of Nrf2 in the nucleus, and activates the ERKN JNK pathway and p38 MAPK pathway. Interestingly, p38 MAPK plays a major role in HO-1 expression induced by O-GSP. And O-GSP can modulate the decrease of Nrf2 and HO-1 expression induced by cisplatin, and improve the cisplatin-induced activity and apoptosis rate of cells by stimulating the expression of HO-1. However, the protective effects of O-GSP are inhibited by ZnPP IX. Collectively, the results indicated that O-GSP induced the expression of HO-1 through p38MAPK and Nrf2 pathway in HEK293 cells.


Assuntos
Antineoplásicos/farmacologia , Biflavonoides/farmacologia , Catequina/farmacologia , Cisplatino/farmacologia , Heme Oxigenase-1/metabolismo , Proantocianidinas/farmacologia , Regulação para Cima/efeitos dos fármacos , Vitis/química , Apoptose/efeitos dos fármacos , Núcleo Celular/metabolismo , Células HEK293 , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Sementes/química , Sementes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vitis/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Chem Biodivers ; 16(10): e1900347, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31532890

RESUMO

Catechins in green tea are well-known to be effective in reducing the risk of obesity. The purpose of this study was to elucidate the effects of catechins present in green tea on adipocyte differentiation and mature adipocyte metabolism. Treatment of 3T3-L1 mouse adipocyte during differentiation adipocytes with (-)-epigallocatechin (EGC) and gallic acid (GA) resulted in dose-dependent inhibition of adipogenesis. Specifically, EGC increased adiponectin and uncoupling protein 1 (UCP1) transcription in mature adipocytes. Transcription levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) were not significantly impacted by either of the compounds. These results suggest that the EGC is the most effective catechin having anti-obesity activity. Finally, EGC is an attractive candidate component for remodeling obesity.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Catequina/análogos & derivados , Células 3T3-L1 , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Catequina/química , Catequina/isolamento & purificação , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Chá/química
4.
J Med Microbiol ; 68(10): 1552-1559, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31419210

RESUMO

Introductio n. Pseudomonas aeruginosa is an important Gram-negative pathogen that is intrinsically multidrug-resistant (MDR) and frequently associated with healthcare-associated outbreaks. With increasing resistance to antibiotics and with very few novel drugs under development, clinicians often use combinations to treat critically ill patients.Aim. The aim of this study was to evaluate the ability of epigallocatechin (EGCG) to restore the activity of aztreonam against clinical MDR strains of P. aeruginosa.Methodology. Checkerboard and time-kill kinetic assays were performed to assess synergy in vitro and the Galleria mellonella model of infection was used to test the efficacy of the combination in vivo. Accumulation assays were performed to gain insight into the mechanism of action.Results. The results demonstrate that synergy between aztreonam and EGCG exists [fractional inhibitory concentration indices (FICIs) 0.02-0.5], with the combination affording significantly (P=<0.05) enhanced bacterial killing, with a >3 log10 reduction in colony-forming units ml-1 at 24 h. EGCG was able to restore susceptibility to aztreonam to a level equal to or below the breakpoint set by the European Committee for Antimicrobial Susceptibility Testing. In G. mellonella, the combination was superior to monotherapy, with increased larval survival observed (94 % vs ≤63 %). We also demonstrated the relatively low toxicity of EGCG to human keratinocytes and G. mellonella larvae. Accumulation assay data suggest that the mechanism of synergy may be due to EGCG increasing the uptake of aztreonam.Conclusion. EGCG was able to restore the activity of aztreonam against MDR P. aeruginosa. The data presented support further evaluation of the aztreonam-EGCG combination and highlight its potential for use in clinical medicine.


Assuntos
Antibacterianos/farmacologia , Aztreonam/farmacologia , Catequina/análogos & derivados , Polifenóis/farmacologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Animais , Catequina/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Humanos , Larva/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento
5.
Int J Nanomedicine ; 14: 5017-5032, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371944

RESUMO

Background: Epigallocatechin gallate (EGCG), the major anti-inflammatory compound in green tea, has been shown to suppress osteoclast (OC) differentiation. However, the low aqueous solubility of EGCG always leads to poor bioavailability, adverse effects, and several drawbacks for clinical applications. Purpose: In this study, we synthesized EGCG-capped gold nanoparticles (EGCG-GNPs) to solve the drawbacks for clinical uses of EGCG in bone destruction disorders by direct reduction of HAuCl4 in EGCG aqueous solution. Methods and Results: The obtained EGCG-GNPs were negatively charged and spherical. Theoretical calculation results suggested that EGCG was released from GNPs in an acidic environment. Cellular uptake study showed an obviously large amount of intracellular EGCG-GNPs without cytotoxicity. EGCG-GNPs exhibited better effects in reducing intracellular reactive oxygen species levels than free EGCG. A more dramatic anti-osteoclastogenic effect induced by EGCG-GNPs than free EGCG was observed in lipopolysaccharide (LPS)-stimulated bone marrow macrophages, including decreased formation of TRAP-positive multinuclear cells and actin rings. Meanwhile, EGCG-GNPs not only suppressed the mRNA expression of genetic markers of OC differentiation but also inhibited MAPK signaling pathways. Furthermore, we confirmed that EGCG-GNPs greatly reversed bone resorption in the LPS-induced calvarial bone erosion model in vivo, which was more effective than applying free EGCG, specifically in inhibiting the number of OCs, improving bone density, and preventing bone loss. Conclusion: EGCG-GNPs showed better anti-osteoclastogenic effect than free EGCG in vitro and in vivo, indicating their potential in anti-bone resorption treatment strategy.


Assuntos
Catequina/análogos & derivados , Ouro/farmacologia , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Reabsorção Óssea/patologia , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Teoria da Densidade Funcional , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ligantes , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Nanopartículas Metálicas/ultraestrutura , Camundongos Endogâmicos BALB C , Modelos Biológicos , Ligante RANK/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Crânio/patologia , Transcrição Genética/efeitos dos fármacos
6.
J Agric Food Chem ; 67(32): 8839-8846, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334651

RESUMO

Natural products are one of the main sources for discovering new lead compounds. We previously reported that cinnamon extract has a promising effect in regulating lipid tissue volume and insulin sensitivity in vivo. However, its effective component and the underlying mechanism are not known. In the present study, we analyzed the effect of different components of cinnamon on regulating insulin sensitivity in 3T3-L1 adipocytes. Functional assay revealed that, of the six major components of cinnamon extracts, the B-type procyanidin, procyanidin C1, improves the differentiation of 3T3-L1 cells (TG content: 1.10 ± 0.09 mM at a dosage of 25 µM vs 0.67 ± 0.02 mM in vehicle group, p < 0.001) and promotes insulin-induced glucose uptake (8.58 ± 1.43 at a dosage of 25 µM vs 3.05 ± 1.24 in vehicle group, p < 0.001). Mechanism studies further suggested that procyanidin C1 activates the AKT-eNOS pathway, thus up-regulating glucose uptake and enhancing insulin sensitivity in mature adipocytes. Taken together, our study identified B-type procyanidin C1, a component of cinnamon extract, that stimulates preadipocyte differentiation and acts as a potential insulin action enhancer through the AKT-eNOS pathway in mature adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Biflavonoides/farmacologia , Catequina/farmacologia , Cinnamomum zeylanicum/química , Insulina/metabolismo , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Animais , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 250-255, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257808

RESUMO

OBJECTIVE: To investigate the protective effects of procyanidin on periprosthetic osteolysis caused by tricalcium phosphate (TCP) wear particles in the mouse calvaria and its mechanism. METHODS: Forty-eight male ICR mice were randomly divided into sham group, TCP group, and procyanidin (0.2 mg/kg, 1 mg/kg, 5 mg/kg)-treated group (n=12). A periprosthetic osteolysis model in the mouse calvaria was established by implanting 30 mg of TCP wear particles onto the surface of bilateral parietal bones following removal of the periosteum. On the 2nd day post-operation, procyanidin (1 mg/kg, 5 mg/kg) was locally injected to the calvaria under the periosteum every other day. After 2 weeks, all the mice were sacrificed to collect the blood samples and the calvaria. Periprosthetic osteolysis and osteoclastogenesis in the mouse calvaria were observed by tartrate resistant acid phosphatase (TRAP) staining and HE staining. mRNA levels of TRAP, capthesin K, c-Fos and NFATc1 in the periprosthestic bone tissue were examined by real-time fluorescence quantitative PCR. Serum contents of total anti-oxidation capacity (T-AOC) and MDA, and superoxide dismutase (SOD) activity were determined by chemical colorimetry. Protein expressions of autophagic biomarkers such as Beclin-1 and LC-3 in periprosthetic bone tissue of the calvaria were examined by Western blot. RESULTS: Compared with sham group, periprosthetic osteolysis, osteoclastogenesis, mRNA levels of TRAP, capthesin K, c-Fos and NFATc1, and serum MDA content were increased significantly in the TCP group (P<0.05), whereas serum T-AOC level and SOD activity were decreased. The protein expressions of Beclin-1 and LC-3, and the conversion of LC3-II from LC3-I were both up-regulated markedly in the mouse calvaria of TCP group (P<0.05). Compared with TCP group, osteolysis, osteoclastogenesis, mRNA levels of TRAP, capthesin K, c-Fos and NFATc1 and serum MDA content were decreased obviously in the procyanidine group (P<0.05), serum T-AOC level and SOD activity were increased, the expressions of Beclin-1 and LC-3, and the conversion of LC3-II from LC3-I were down-regulated obviously in the mouse calvaria of procyanidin group (P<0.05). CONCLUSION: Procyanidin has a protective effect of periprosthetic osteolysis caused by TCP wear particles in the mouse calvaia, its mechanism may be mediated by inhibition of oxidative stress and autophagy.


Assuntos
Biflavonoides/farmacologia , Fosfatos de Cálcio/efeitos adversos , Catequina/farmacologia , Osteólise , Proantocianidinas/farmacologia , Próteses e Implantes/efeitos adversos , Animais , Autofagia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo , Distribuição Aleatória , Crânio
8.
Bioengineered ; 10(1): 282-291, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31311401

RESUMO

Transforming growth factor (TGF)-ß1 plays a crucial role in the epithelial-to-mesenchymal transition (EMT) in many cancer types and in thyroid cancers. Epigallocatechin-3-gallate (EGCG), the most important ingredient in the green tea, has been reported to possess antioxidant and anticancer activities. However, the cellular and molecular mechanisms explaining its action have not been completely understood. In this study, we found that EGCG significantly suppresses EMT, invasion and migration in anaplastic thyroid carcinoma (ATC) 8505C cells in vitro by regulating the TGF-ß/Smad signaling pathways. EGCG significantly inhibited TGF-ß1-induced expression of EMT markers (E-cadherin reduction and vimentin induction) in 8505C cells in vitro. Treatment with EGCG completely blocked the phosphorylation of Smad2/3, translocation of Smad4. Taken together, these results suggest that EGCG suppresses EMT and invasion and migration by blocking TGFß/Smad signaling pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Catequina/análogos & derivados , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais/efeitos dos fármacos , Células Epiteliais da Tireoide/efeitos dos fármacos , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/antagonistas & inibidores , Caderinas/genética , Caderinas/metabolismo , Catequina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Humanos , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Células Epiteliais da Tireoide/metabolismo , Células Epiteliais da Tireoide/patologia , Fator de Crescimento Transformador beta1/farmacologia , Vimentina/agonistas , Vimentina/genética , Vimentina/metabolismo
9.
Phytother Res ; 33(9): 2274-2287, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31309655

RESUMO

Catechin in green tea might be able to reduce inflammatory mediators; therefore, in this study, we aimed to indicate green tea effects on inflammatory mediators such as tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), and interleukin-6 (IL-6). The advanced search methods of electronic databases were used to find randomized clinical trials that assessed green tea effect on inflammatory mediators among adult population. Google Scholar, PubMed/Medline, EMBASE, SCOPUS, and ISI Web of Science were searched until January 2019. Delphi checklist was used for assessing the quality of included articles. Mean changes in serum inflammatory biomarkers were calculated by subtracting endpoint values from the baseline in each study arm. Then the effect size for each selected study was estimated as the difference between mean changes in the intervention and control groups. We included 16 articles in our meta-analysis and 17 articles in systematic review. Our results indicated that green tea could not significantly decrease serum CRP levels and significantly increased IL-6 and significantly decreased TNF-α levels. In conclusion, green tea might not be able to change inflammatory mediators especially in diseases with low inflammation, but scientists who want to assess green tea effect on inflammatory mediators should perform their study on patients with high inflammation. Studies exclusive on male or female and considering nutrients intake as a confounding factor are a necessity.


Assuntos
Proteína C-Reativa/uso terapêutico , Catequina/uso terapêutico , Mediadores da Inflamação/uso terapêutico , Inflamação/tratamento farmacológico , Chá/química , Proteína C-Reativa/farmacologia , Catequina/farmacologia , Feminino , Humanos , Inflamação/sangue , Mediadores da Inflamação/farmacologia , Interleucina-6/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Fitoterapia ; 137: 104240, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201887

RESUMO

Anhua dark tea known as the earliest produced Chinese dark tea, has been commercially available and famous for its unique flavor and health care effect. NMDA receptors are glutamate-coupled ion channels that critically involved in survival of neuronal cells and neurodegenerative diseases. Thus, it is considered a promising target for the therapy of neurodegenerative disease. In this study, four catechins including two new catechins derivatives (1-2), together with thirteen known flavonoids were isolated from Anhua dark tea. The structures of compounds 1-2 [2S,3R-6-methoxycarbonylgallocatechin (1) and 2R,3R-6-methoxycarbonylgallocatechin (2)] were determined on the basis of their spectroscopic data. The preliminary bioassay indicated that compound 1 showed the best neuroprotective effects via N-methyl-d-aspartate (NMDA) receptors inhibition. Compound 1 protected SH-SY5Y cells against NMDA-induced injury and cell apoptosis via the modulation of NR2B expression, the activation of PI3K/Akt signaling and caspase-dependent pathway. The results suggested compound 1 would be a potent dietary therapy reagent for prevention of excitable brain injury.


Assuntos
Catequina/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Chá/química , Apoptose , Catequina/análogos & derivados , Linhagem Celular Tumoral , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Neuroblastoma , Fármacos Neuroprotetores/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
11.
Int J Pediatr Otorhinolaryngol ; 124: 106-110, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176023

RESUMO

INTRODUCTION: That EGCG has strong antioxidant and anti-inflammatory activities as well as antibacterial activity against many streptococcus species suggests that it may be beneficial in the treatment of AOM. OBJECTIVE: Aim of the study is to reveal the molecular and biochemical effects of EGCG on LPS induced otitis media in rats. METHODS: Forty-two male albino Wistar rats were randomly divided into 7 groups. Inflammation was induced by administrating 50 µL of 1 mg/ml lipopolysaccharide (LPS). EGCG used 50 and 100 mg/kg/day and combined penicillin G (PENG) 48 h after LPS injection. RESULTS: The combined EGCG 50 and PENG group and the group with EGCG 50 alone showed the best anti-inflammatory effect on LPS-induced AOM. TNF-α and IL-1ß gene expression significantly down regulated EGCG 50 and combined with PENG compared to the otitis media group. The combination of PenG and EGCG 50 led to the best histopathological improvement. Both the inflammation and the membrane thickness of this group were at almost the same level as the healthy group and tympanum was seen normal. CONCLUSION: The results of this study make it clear that EGCG plays an important role in antioxidant and anti-inflammatory activity during AOM.


Assuntos
Antioxidantes/uso terapêutico , Catequina/análogos & derivados , Otite Média/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Antioxidantes/farmacologia , Catequina/farmacologia , Catequina/uso terapêutico , Regulação para Baixo , Quimioterapia Combinada , Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/genética , Lipopolissacarídeos , Masculino , Otite Média/induzido quimicamente , Otite Média/patologia , Penicilina G/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/genética , Membrana Timpânica/patologia
12.
Environ Pollut ; 252(Pt B): 1318-1324, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31252129

RESUMO

The increase in ambient fine dust particles (FDP) due to urbanization and industrialization has been identified as a major contributor to air pollution. It has become a serious issue that threatens human health because it causes respiratory diseases and skin aging. In the present study, the protective effect of the green tea catechin, (-)-epigallocatechin gallate (EGCG), against FDP (ERM-CZ100)-stimulated skin aging in human dermal fibroblasts (HDFs) was investigated. The results demonstrate that EGCG significantly and dose-dependently scavenged intracellular reactive oxygen species (ROS) in and increased the viability of FDP-stimulated HDFs. In addition, EGCG dose-dependently recovered collagen synthesis and inhibited intracellular elastase and collagenase activities. Moreover, EGCG decreased the expression of human matrix metalloproteinases (MMPs) via regulation of nuclear factor kappa B (NF-κB), activator protein 1 (AP-1), and mitogen-activated protein kinases (MAPKs) signaling pathways in FDP-stimulated HDFs. This study suggests that EGCG is a potential anti-aging candidate that can be used for FDP-induced skin aging as a therapeutic agent itself or as an ingredient in pharmaceutical and cosmeceutical products.


Assuntos
Catequina/análogos & derivados , Sistema de Sinalização das MAP Quinases/fisiologia , NF-kappa B/metabolismo , Material Particulado/efeitos adversos , Envelhecimento da Pele/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Catequina/farmacologia , Linhagem Celular , Colagenases , Poeira/análise , Fibroblastos/efeitos dos fármacos , Humanos , Inibidores de Metaloproteinases de Matriz/farmacologia , Elastase Pancreática/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Pele/fisiopatologia , Envelhecimento da Pele/fisiologia , Chá/química
13.
Chemosphere ; 233: 110-119, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31173951

RESUMO

Conventional microbial treatments are challenged by new synthetic refractory dyes. In this work, tea residue was found serving as an effective activator to boost the decolorization performance of anthraquinone dye (reactive blue 19, RB19) by a new bacterial flora DDMY2. The unfermented West Lake Longjing tea residue showed the best enhancement performance. Seventeen main kinds of components in tea residue had been selected to take separate and orthogonal experiments on decolorization of RB19 by DDMY2. Results suggested epigallocatechin gallate (EGCG) in tea residue played important roles in boosting the treatment performance. Illumina MiSeq sequencing results confirmed that EGCG and tea residue pose similar impact on the change of DDMY2 community structure. Some functional bacterial genera unclassified_o_Pseudomonadales, Stenotrophomonas and Bordetella were enriched during the treatment of RB19 by EGCG and tea residue. These evidences suggested EGCG might be the key active component in tea residue that responsible for the enhancement effect on decolorization performance. These results revealed the activating mechanism of tea residue from the perspective of composition.


Assuntos
Antraquinonas/metabolismo , Bactérias/metabolismo , Corantes/metabolismo , Chá/química , Antraquinonas/química , Bactérias/efeitos dos fármacos , Biodegradação Ambiental , Catequina/análogos & derivados , Catequina/farmacologia , Corantes/química , Esgotos/microbiologia , Resíduos
14.
Molecules ; 24(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058847

RESUMO

Due to changes in the dietary structure of individuals, the incidence of digestive tract tumors has increased significantly in recent years, causing a serious threat to the life and health of patients. This has in turn led to an increase in cancer prevention research. Many studies have shown that epigallocatechin-3-gallate (EGCG), an active ingredient in green tea, is in direct contact with the digestive tract upon ingestion, which allows it to elicit a significant antagonizing effect on digestive tract tumors. The main results of EGCG treatment include the prevention of tumor development in the digestive tract and the induction of cell cycle arrest and apoptosis. EGCG can be orally administered, is safe, and combats other resistances. The synergistic use of cancer drugs can promote the efficacy and reduce the anti-allergic properties of drugs, and is thus, favored in medical research. EGCG, however, currently possesses several shortcomings such as poor stability and low bioavailability, and its clinical application prospects need further development. In this paper, we have systematically summarized the research progress on the ability of EGCG to antagonize the activity and mechanism of action of digestive tract tumors, to achieve prevention, alleviation, delay, and even treat human gastrointestinal tract tumors via exogenous dietary EGCG supplementation or the development of new drugs containing EGCG.


Assuntos
Catequina/análogos & derivados , Ciclo Celular/efeitos dos fármacos , Neoplasias Gastrointestinais/tratamento farmacológico , Administração Oral , Disponibilidade Biológica , Catequina/administração & dosagem , Catequina/farmacocinética , Catequina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Humanos , Chá/química
15.
J Biomed Sci ; 26(1): 32, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31064352

RESUMO

BACKGROUND: Our previous studies have demonstrated that Ca2+ desensitizing catechin could correct diastolic dysfunction in experimental animals with restrictive cardiomyopathy. In this study, it is aimed to assess the effects of green tea extract catechin on cardiac function and other clinical features in pediatric patients with cardiomyopathies. METHODS: Twelve pediatric cardiomyopathy patients with diastolic dysfunction were enrolled for the study. Echocardiography, ECG, and laboratory tests were performed before and after the catechin administration for 12 months. Comparison has been made in these patients before and after the treatment with catechin. Next Generation Sequencing was conducted to find out the potential causative gene variants in all patients. RESULTS: A significant decrease of isovolumetric relaxation time (115 ± 46 vs 100 ± 42 ms, P = 0.047 at 6 months; 115 ± 46 vs 94 ± 30 ms, P = 0.033 at 12 months), an increase of left ventricle end diastolic volume (40 ± 28 vs 53 ± 28 ml, P = 0.028 at 6 months; 40 ± 28 vs 48 ± 33 ml, P = 0.011 at 12 months) and stroke volume (25 ± 16 vs 32 ± 17 ml, P = 0.022 at 6 months; 25 ± 16 vs 30 ± 17 ml, P = 0.021 at 12 months) were observed with echocardiography in these patients 6-month after the treatment with catechin. Ejection fraction, left ventricular wall thickness, biatrial dimension remained unchanged. No significant side effects were observed in the patients tested. CONCLUSIONS: This study indicates that Ca2+ desensitizing green tea extract catechin, is helpful in correcting the impaired relaxation in pediatric cardiomyopathy patients with diastolic dysfunction.


Assuntos
Camellia sinensis/química , Cardiomiopatias/tratamento farmacológico , Catequina/farmacologia , Extratos Vegetais/farmacologia , Adolescente , Criança , Pré-Escolar , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Lactente , Masculino
16.
J Appl Microbiol ; 127(3): 763-777, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31125995

RESUMO

AIMS: Pseudomonas fluorescens are important psychrotrophic food spoilage bacteria that are frequently detected in dairy, meat and aquatic products. Quorum sensing (QS) is an intercellular communication and gene regulation mechanism that enables bacteria to monitor their cell densities and regulate a variety of physiological processes. Hence, targeting the bacterial QS system might be a feasible approach to improve food quality and safety by regulating the spoilage caused by P. fluorescens. METHODS AND RESULTS: In this study, we screened a food-derived three-dimensional (3D) compound database to search for potential QS inhibitors (QSIs) with higher security. The 3D structures of LuxI- and LuxR-type proteins of P. fluorescens P07 were used as targets to screen for QSIs. A total of 25 compounds with high docking scores were tested for their anti-QS activities by indicator strains. The results show that 19 compounds possessed anti-QS activities. Among them, (+)-catechin had the strongest anti-QS activity. The results show that (+)-catechin significantly inhibited the production of extracellular enzymes, swimming motility, biofilm formation, acyl-homoserine lactones and extracellular polymeric substances (EPSs) of P. fluorescens P07. The inhibitory mechanism of (+)-catechin on the QS system of P. fluorescens P07 was discussed in the context of molecular docking analysis and real-time quantitative PCR (RT-qPCR). CONCLUSIONS: Virtual screening was useful in finding novel QSIs with high security of P. fluorescens P07 from a food-derived 3D compound database. The high hit rate suggested that foods are rich sources of QSIs, and have great potential for exploration. SIGNIFICANCE AND IMPACT OF THE STUDY: The modelled LuxI- and LuxR-type proteins could be used as targets to discover P. fluorescens P07 QSIs. (+)-catechin, (-)-epicatechin, propyl gallate, hesperidin and lycopene which were identified as potent QSIs, and may be applied in food preservation and biofilm elimination.


Assuntos
Catequina/farmacologia , Pseudomonas fluorescens/fisiologia , Percepção de Quorum/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Catequina/química , Catequina/isolamento & purificação , Biologia Computacional , Bases de Dados de Compostos Químicos , Simulação de Acoplamento Molecular
17.
Molecules ; 24(10)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137712

RESUMO

Utilizing bioassay- and TLC-guided column chromatography, fifteen secondary metabolites from Populus alba and eight compounds from Salix subserrata were isolated, including a novel plant metabolite salicyl ether and characterized using ultralviolet light (UV) absorbance, mass spectrometry (MS), 1H-, 13C-NMR (nuclear magnetic resonance), heteronuclear single quantum coherence spectroscopy (HSQC) and heteronuclear multiple bond correlation (HMBC). The extracts, their sub-fractions and the isolated compounds exhibited promising antioxidant activities in vitro in DPPH and FRAP assays. Also, the extracts of P. alba leaf (PL), shoots (PS), and S. subserrata leaf (SL) demonstrated substantial antioxidant activities in vivo in the multicellular model organism Caenorhabditis elegans. For the first time, the isolated secondary metabolites, aromadendrin, tremuloidin, salicin, isorhamnetin-3-O-ß-d-rutinoside, gallocatechin, triandrin, and chrysoeriol-7-O-glucuronide were investigated. They exhibited substantial antioxidant activities in vivo. Salicin, isorhamnetin-3-O-ß-d-rutinoside and gallocatechin, in particular, protected the worms against a lethal dose of the pro-oxidant juglone (80 µM), decreased the endogenous reactive oxygen species (ROS) level to 45.34%, 47.31%, 68.09% and reduced juglone- induced hsp-16.2::GFP (green fluorescence protein) expression to 79.62%, 70.17%, 26.77%, respectively. However, only gallocatechin induced higher levels of sod-3 expression. These findings support the traditional use of Populus alba and Salix subserrata for treating inflammation especially when ROS are involved.


Assuntos
Caenorhabditis elegans/fisiologia , Estresse Oxidativo , Fenóis/farmacologia , Populus/química , Salix/química , Animais , Antioxidantes/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Compostos de Bifenilo/química , Caenorhabditis elegans/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/farmacologia , Flavonoides/análise , Recuperação de Fluorescência Após Fotodegradação , Proteínas de Fluorescência Verde/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenóis/isolamento & purificação , Picratos/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo
18.
Int J Mol Sci ; 20(10)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31100973

RESUMO

It is known that green tea helps prevent obesity and diabetes mellitus. In this study, we aimed to determine whether green tea ameliorates hyperglycemia and the mechanism involved in diabetic rodents. Green tea consumption reduced blood glucose and ameliorated glucose intolerance, which was assessed using an oral glucose tolerance test in both streptozotocin-induced type 1 diabetic rats and type 2 diabetic KK-Ay mice. Green tea also reduced the plasma fructosamine and glycated hemoglobin concentrations in both models. Furthermore, it increased glucose uptake into the skeletal muscle of both model animals, which was accompanied by greater translocation of glucose transporter 4 (GLUT4). Moreover, epigallocatechin gallate (EGCG), the principal catechin in green tea, also ameliorated glucose intolerance in high-fat diet-induced obese and diabetic mice. These results suggest that green tea can ameliorate hyperglycemia in diabetic rodents by stimulating GLUT4-mediated glucose uptake in skeletal muscle, and that EGCG is one of the effective compounds that mediate this effect.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Transportador de Glucose Tipo 4/metabolismo , Hiperglicemia/prevenção & controle , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Extratos Vegetais/farmacologia , Chá/química , Animais , Catequina/análogos & derivados , Catequina/farmacologia , Dieta Hiperlipídica , Frutosamina/sangue , Glucose/metabolismo , Intolerância à Glucose/metabolismo , Intolerância à Glucose/prevenção & controle , Teste de Tolerância a Glucose , Hemoglobina A Glicada , Hiperglicemia/metabolismo , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/prevenção & controle , Ratos , Ratos Wistar , Roedores , Estreptozocina/farmacologia
19.
Molecules ; 24(9)2019 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31060206

RESUMO

Chemical and biological investigation of green tea has been generally performed while using different infusions that are prepared without consideration of the effects of sample preparation conditions. In this study, for the first time, the effects of green tea brewing conditions on the antioxidant activity and chemical profiles of metabolome and catechin compounds were examined at 60 °C and 95 °C for a period of 5-300 min. The antioxidant capacities of the tea infusions, which were assessed as per 2,2-diphenyl-1-picryl-hydrazyl hydrate (DPPH) radical scavenging activity, depended more on temperature than time. Metabolomics study that was based on ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF/MS) revealed that the metabolic profiles, including 33 differential metabolites, were significantly changed by temperature and time, with the effects of time being more evident at 95 °C starting after 30 min. Infusions that were brewed at 95 °C for greater than 30 min yielded distinct profiles in the hierarchical clustering analysis. The quantification of eight catechins by UHPLC-QqQ/MS showed that the total catechin level peaked at 95 °C brewing at 10 min, after which the levels of four epi-forms of catechins decreased and those of four non-epi-forms increased, implying the epimerization of catechins over time. These results suggest that the brewing conditions for sample preparation of green tea should be put into careful consideration in studies where green tea extracts are applied as aqueous infusions.


Assuntos
Antioxidantes/análise , Catequina/análise , Metabolômica/métodos , Chá/química , Antioxidantes/química , Antioxidantes/farmacologia , Catequina/química , Catequina/farmacologia , Cromatografia Líquida de Alta Pressão , Temperatura Alta , Espectrometria de Massas , Extratos Vegetais/química
20.
Molecules ; 24(10)2019 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31109031

RESUMO

The structure of a new procyanidin tetramer, which we call a crown procyanidin tetramer, with an unprecedented macrocyclic structure has been characterized for the first time. Its comprehensive spectroscopic analysis revealed that it is a symmetric procyanidin tetramer composed of four (-)-epicatechin sub-units linked alternatively via 4ß→8 or 4ß→6 B-type interflavanyl linkages to form the macrocyclic structure. This NMR-characterized carbon skeleton has never been reported before for procyanidins in grape or in wine, neither in the plant kingdom. Surprisingly, the crown procyanidin tetramer appeared to be specifically localized in grape skin, contrasting with the oligomeric and polymeric procyanidins present in seed, skin, and bunch stem. Moreover, this crown procyanidin tetramer showed promising protective effects against amyloid-ß induced toxicity.


Assuntos
Biflavonoides/química , Biflavonoides/farmacologia , Catequina/química , Catequina/farmacologia , Proantocianidinas/química , Proantocianidinas/farmacologia , Multimerização Proteica , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/toxicidade , Animais , Biflavonoides/isolamento & purificação , Catequina/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Proantocianidinas/isolamento & purificação , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Vitis/química
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