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1.
Ecotoxicol Environ Saf ; 266: 115568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832482

RESUMO

The tea plant accumulates elevated levels of fluoride (F) from environmental sources. Drinking tea containing high F levels poses a potential threat to human health. Selenium (Se) was applied by foliar spray to investigate its effects on F accumulation and physiology in tea plant. Foliar application of different forms of Se, i.e., Na2SeO3, Kappa-selenocarrageenan, Selenomethionine and Nanoselenium, reduced F content in tea leaves by 10.17 %-44.28 %, 16.12 %-35.41 %, 22.19 %-45.99 % and 22.24 %-43.82 %, respectively. Foliar spraying Se could increase F accumulation in pectin through increasing pectin content and pectin demethylesterification to bind more F in the cell wall, which decreased the proportion of water-soluble fluoride in tea leaves. Application of Se significantly decreased the contents of chromium (39.6 %-72.0 %), cadmium (48.3 %-84.4 %), lead (2.2 %-44.4 %) and copper (14.1 %-44.6 %) in tea leaves. Foliar spraying various forms of Se dramatically increased the Se content and was efficiently transformed into organic Se accounting for more than 80 % in tea leaves. All Se compounds increased peroxidase activity by 3.3 %-35.5 % and catalase activity by 2.6 %-99.4 %, reduced malondialdehyde content by 5.6 %-37.1 %, and increased the contents of chlorophyll by 0.65 %-31.8 %, carotenoids by 0.24 %-27.1 %, total catechins by 1.6 %-21.0 %, EGCG by 4.4 %-17.6 % and caffeine by 9.1 %-28.6 %. These results indicated that Se application could be served as a potential efficient and safe strategy diminishing the concentration of F in tea leaves.


Assuntos
Camellia sinensis , Selênio , Humanos , Selênio/metabolismo , Fluoretos/análise , Antioxidantes/metabolismo , Camellia sinensis/química , Folhas de Planta/metabolismo , Chá , Pectinas/metabolismo
2.
Molecules ; 28(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37570841

RESUMO

Theaflavins (TFs), the primary bioactive components in black tea, are poorly absorbed in the small intestine. However, the biological activity of TFs does not match their low bioavailability, which suggests that the gut microbiota plays a crucial role in their biotransformation and activities. In this study, we aimed to investigate the biotransferred metabolites of TFs produced by the human gut microbiota and these metabolites' function. We profiled the microbial metabolites of TFs by in vitro anaerobic human gut microbiota fermentation using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods. A total of 17 microbial metabolites were identified, and their corresponding metabolic pathways were proposed. Moreover, full-length 16S rRNA gene sequence analysis revealed that the TFs altered the gut microbiota diversity and increased the relative abundance of specific members of the microbiota involved in the catabolism of the TFs, including Flavonifractor_plautii, Bacteroides_uniformis, Eubacterium_ramulus, etc. Notably, the antioxidant capacity of the TF sample increased after fermentation compared to the initial sample. In conclusion, the results contribute to a more comprehensive understanding of the microbial metabolites and antioxidant capacity of TFs.


Assuntos
Camellia sinensis , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Cromatografia Líquida , Antioxidantes/farmacologia , Antioxidantes/análise , Chá/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/análise , Fezes/química , Espectrometria de Massas em Tandem , Camellia sinensis/genética
3.
Proc Natl Acad Sci U S A ; 115(18): E4151-E4158, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29678829

RESUMO

Tea, one of the world's most important beverage crops, provides numerous secondary metabolites that account for its rich taste and health benefits. Here we present a high-quality sequence of the genome of tea, Camellia sinensis var. sinensis (CSS), using both Illumina and PacBio sequencing technologies. At least 64% of the 3.1-Gb genome assembly consists of repetitive sequences, and the rest yields 33,932 high-confidence predictions of encoded proteins. Divergence between two major lineages, CSS and Camellia sinensis var. assamica (CSA), is calculated to ∼0.38 to 1.54 million years ago (Mya). Analysis of genic collinearity reveals that the tea genome is the product of two rounds of whole-genome duplications (WGDs) that occurred ∼30 to 40 and ∼90 to 100 Mya. We provide evidence that these WGD events, and subsequent paralogous duplications, had major impacts on the copy numbers of secondary metabolite genes, particularly genes critical to producing three key quality compounds: catechins, theanine, and caffeine. Analyses of transcriptome and phytochemistry data show that amplification and transcriptional divergence of genes encoding a large acyltransferase family and leucoanthocyanidin reductases are associated with the characteristic young leaf accumulation of monomeric galloylated catechins in tea, while functional divergence of a single member of the glutamine synthetase gene family yielded theanine synthetase. This genome sequence will facilitate understanding of tea genome evolution and tea metabolite pathways, and will promote germplasm utilization for breeding improved tea varieties.


Assuntos
Camellia sinensis/genética , Evolução Molecular , Duplicação Gênica , Genoma de Planta , Chá , Camellia sinensis/metabolismo
4.
J Pharmacol Exp Ther ; 371(3): 663-674, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31582423

RESUMO

At concentrations found in humans after ingestion of one to two cups of green tea, epicatechin-3-gallate (ECG) modulates Na/K-ATPase conformation and activity. Akin to ouabain, an archetypal Na/K-ATPase ligand of the cardiotonic steroid (CTS) family, ECG also activates protein kinase C epsilon type (PKCε) translocation and increases the force of contraction of the rat heart. This study evaluated whether, like ouabain, ECG also modulates Na/K-ATPase/Src receptor function and triggers pre- and postconditioning against ischemia/reperfusion (I/R) injury. In vitro, ECG activated the purified Na/K-ATPase/Src complex. In Langendorff-perfused rat hearts, submicromolar concentrations of ECG administered either before or after ischemia reduced infarct size by more than 40%, decreased lactate dehydrogenase release, and improved the recovery of cardiac function. ECG protection was blocked by PKCε inhibition and attenuated by mitochondrial KATP channel inhibition. In a unique mammalian cell system with depleted Na/K-ATPase α1 expression, ECG-induced PKCε activation persisted but protection against I/R was blunted. Taken together, these results reveal a Na/K-ATPase- and PKCε-dependent mechanism of protection by ECG that is also distinct from the mechanism of action of ouabain. These ECG properties likely contribute to the positive impact of green tea consumption on cardiovaascular health and warrant further investigation into the role of cardiac Na/K-ATPase signaling in the cardioprotective effect of green tea consumption. SIGNIFICANCE STATEMENT: Consumption of green tea, the richest dietary source of ECG, is associated with a reduced risk of cardiac mortality. Antioxidant effects of ECG and other tea polyphenols are well known, but reported for concentrations well above dietary levels. Therefore, the mechanism underlying the cardioprotective effect of green tea remains incompletely understood. This study provides experimental evidence that ECG concentrations commonly detected in humans after consumption of a cup of tea trigger the Na/K-ATPase/Src receptor in a cell-free system, activate a CTS-like signaling pathway, and provide PKCε-dependent protection against ischemia/reperfusion injury in rat hearts. Mechanistic studies in mammalian cells with targeted Na/K-ATPase depletion revealed that although Na/K-ATPase does not mediate ECG-induced PKCε activation, it is required for ECG-induced protection against ischemia/reperfusion injury.


Assuntos
Catequina/análogos & derivados , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Catequina/farmacologia , Células Cultivadas , Masculino , Extratos Vegetais/farmacologia , Canais de Potássio/fisiologia , Proteína Quinase C-épsilon/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos , Chá
5.
Cancer Cell Int ; 19: 206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31388333

RESUMO

BACKGROUND: Micronuclei (MNi) are extensively used to evaluate genotoxic effects and chromosome instability. However, the roles of kinetochore of MN in mitosis have not been completely addressed. METHODS: The HeLa CENP B-GFP H2B-mCherry cells are applied to address these questions via the long-term live-cell imaging. In the cells, the kinetochore-positive micronucleus (K+MN) contained CENP B-GFP, while the kinetochore-negative micronucleus (K-MN) did not. RESULTS: K-MN-bearing cells produced much more chromosome fragments than did MN-free cells. Most of the chromosome fragments eventually merged into K-MNi. K+MN-bearing cells yielded more kinetochore-positive lagging chromosomes (K+LCs) and K+MNi than MN-free cells did. The results suggested the differences in the fates of K+MNi and K-MNi in mitosis. The cycle of K-MN → Chromosome fragment → K-MN may occur in generations of K-MN-bearing cells, while part of K+MNi might reincorporate into the main nucleus. The K+MN-bearing cells prolonged significantly duration of mitosis compared with MN-free cells. The presence of micronuclei, regardless of K-MN and K+MN, enhanced apoptosis cell death. And K+MN-bearing cells were inclined to apoptosis more than K-MN-bearing cells. The results suggested differences in fates between K-MN-bearing and K+MN-bearing cells. CONCLUSIONS: Kinetochore determined the fates of micronuclei. Kinetochore in micronuclei indirectly prolonged the duration of mitosis. Kinetochore enhanced cytotoxicity of micronuclei. Our data are direct evidences showing the roles of kinetochore of micronucleus in mitosis of HeLa cells.

6.
J Food Sci Technol ; 56(10): 4632-4647, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686695

RESUMO

This study investigated the effect of brewing apparatus on the aromatic feature of tea infusion. Huangshan Maofeng tea infusion was brewed under glass tumblers (GT) or thermos vacuum mugs (TVM) for up to 180 min. Tea infusion sensory attributes were evaluated using quantitative descriptive analysis and the composition of volatiles were analyzed using headspace solid phase microextraction coupled with gas chromatography-mass spectrometry. Results showed that GT tea infusion at each brewing duration possessed stronger 'Pure', 'Fresh' and 'Grassy' attributes than TVM tea infusion, whereas TVM tea infusion showed a higher intensity on 'Steamed' aroma. A total of 74 volatiles were detected in tea infusion, and aldehydes and alcohols appeared to be the major volatiles. Total aldehydes concentration percentage decreased in tea infusion with brewing process, whereas an increase on total alcohol percentage was found. Principal component analysis indicated that brewing duration and apparatus played vital roles in altering the volatile composition in tea infusion, whereas orthogonal partial least squares discriminant analysis (OPLS-DA) revealed that GT tea infusion samples were separated from TVM tea infusion samples. OPLS-DA also screened 20 volatiles that significantly contributed to the differentiation of GT and TVM tea infusion.

7.
J Food Sci Technol ; 55(10): 4276-4286, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30228426

RESUMO

We describe a novel analytical method for quantification of free amino acids in tea using variable mobile phase pH, elution gradient and column temperature of reversed-phase high-performance liquid chromatography (RP-HPLC). The study of mobile phase pH 5.7 was chosen to simultaneous quantification of 19 free amino acids in tea, while it improved maximum resolution of glutamine, histidine and theanine. Elution gradient was adapted for enhancing the solution of free amino acids, mainly because of adjustment of mobile phase A and B. The column temperature of 40 °C was conducive to separate free amino acids in tea. The limit of detection (LOD) and limit of quantitation (LOQ) of this method were in the range of 0.097-0.228 nmol/mL and 0.323-0.761 nmol/mL, respectively. The relative standard deviation of intraday and interday ranged in 0.099-1.909% and 3.231-7.025%, respectively, indicating that the method was reproducible and precise, while recovery ranged between 81.06-112.78%, showing that the method had an acceptable accuracy. This method was applied for the quantification of free amino acids in six types of tea. Multivariate analysis identified serine, glutamine, theanine and leucine as the most influencing factor for classify among analyzed sample.

8.
J Sci Food Agric ; 97(5): 1509-1516, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27404035

RESUMO

BACKGROUND: Brick tea usually contains very high fluoride, which may affect human health. Biosorbents have received much attention for selective removal of fluoride because of low cost, environmental friendliness, and relative safeness. RESULTS: In the present study, a highly selective fluoride tea waste based biosorbent, namely, aluminum (Al) oxide decorated tea waste (Tea-Al), was successfully prepared. The Tea-Al biosorbent was characterized by energy-dispersive spectrometry, Fourier transform infrared spectroscopy, powder X-ray diffraction and X-ray photoelectron spectroscopic analysis. The Tea-Al sample exhibited remarkably selective adsorption for fluoride (52.90%), but a weaker adsorption for other major constituents of brick tea infusion, such as catechins, polyphenols and caffeine, under the same conditions. Fluoride adsorption by Tea-Al for different times obeyed the surface reaction and adsorption isotherms fit the Freundlich model. In addition, the fluoride adsorption mechanism appeared to be an ion exchange between hydroxyl and fluoride ions. CONCLUSION: Results from this study demonstrated that Tea-Al is a promising biosorbent useful for the removal of fluoride in brick tea infusion. © 2016 Society of Chemical Industry.


Assuntos
Óxido de Alumínio/química , Camellia sinensis/química , Fluoretos/química , Chá/química , Adsorção , Contaminação de Alimentos/prevenção & controle
9.
Pharm Biol ; 55(1): 2123-2128, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28938867

RESUMO

CONTEXT: Tea (Camellia sinensis (L.) Kuntze [Theaceae]) is used to induce urination and inducing nervous excitation. Green and black teas have multifarious physiological functions. The different effects of green and black tea aqueous extracts (GTEs and BTEs) on hyperuricemia are not definitely reported. OBJECTIVE: The different effects of GTEs and BTEs on lowering serum uric acid (UA) in hyperuricemic mice were determined. MATERIALS AND METHODS: Kunming mice were divided into nine groups (n = 6/each group). GTEs and BTEs at the doses of 0.5, 1 and 2 g/kg were orally administrated to mice for seven days, respectively. Hepatic xanthine oxidase (XOD) and adenosine deaminase (ADA) activities as mechanisms of actions were assessed. RESULTS: Research indicated that the LD50 of tea extract is greater than 2 g/kg in mice. UA levels were suppressed significantly with dose-dependent treatment of 0.5, 1 and 2 g/kg BTEs (up to 25.5%, 28.7% and 29.8%, respectively); the serum UA levels were decreased by GTEs but not significant. The activities of XOD and ADA in high dose (2 g/kg) groups of both GTEs and BTEs were notably lower than those of the model group. DISCUSSION AND CONCLUSIONS: The results suggested that both GTEs and BTEs have hypouricaemic and renal protective effects on hyperuricemic mice and the latter one was better. Our study sheds light on the research and development of anti-hyperuricemic functional foods and drugs from tea.


Assuntos
Hiperuricemia/sangue , Hiperuricemia/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Chá , Ácido Úrico/sangue , Administração Oral , Animais , Biomarcadores/sangue , Camellia sinensis , Relação Dose-Resposta a Droga , Masculino , Camundongos , Extratos Vegetais/isolamento & purificação , Resultado do Tratamento , Ácido Úrico/antagonistas & inibidores
10.
Physiol Genomics ; 48(10): 739-748, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27519543

RESUMO

Binding of ouabain to cardiac Na+/K+-ATPase initiates cell signaling and causes contractility in cardiomyocytes. It is widely accepted that caveolins, structural proteins of caveolae, have been implicated in signal transduction. It is known that caveolae play a role in Na+/K+-ATPase functions. Regulation of caveolin-1 in ouabain-mediated cardiac signaling and contractility has never been reported. The aim of this study is to compare ouabain-induced cardiac signaling and contractility in wild-type (WT) and caveolin-1 knockout (cav-1 KO) mice. In contrast with WT cardiomyocytes, ouabain-induced signaling e.g., activation of phosphoinositide 3-kinase-α/Akt and extracellular signal-regulated kinases (ERK)1/2, and hypertrophic growth were significantly reduced in cav-1 KO cardiomyocytes. Interactions of the Na+/K+-ATPase α1-subunit with caveolin-3 and the Na+/K+-ATPase α1-subunit with PI3K-α were also decreased in cav-1 KO cardiomyocytes. The results from cav-1 KO mouse embryonic fibroblasts also proved that cav-1 significantly attenuated ouabain-induced ERK1/2 activation without alteration in protein and cholesterol distribution in caveolae/lipid rafts. Intriguingly, the effect of ouabain induced positive inotropy in vivo (via transient infusion of ouabain, 0.48 nmol/g body wt) was not attenuated in cav-1 KO mice. Furthermore, ouabain (1-100 µM) induced dose-dependent contractility in isolated working hearts from WT and cav-1 KO mice. The effects of ouabain on contractility between WT and cav-1 KO mice were not significantly different. These results demonstrated differential roles of cav-1 in the regulation of ouabain signaling and contractility. Signaling by ouabain, in contrast to contractility, may be a redundant property of Na+/K+-ATPase.


Assuntos
Caveolina 1/metabolismo , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ouabaína/farmacologia , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Colesterol/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Fosfatidilinositol 3-Quinases/metabolismo
11.
Ecotoxicol Environ Saf ; 131: 14-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27162130

RESUMO

This study investigated the fluoride present in tea plants (Camellia sinensis (L.) O. Kuntze) and its relationship to soils, varieties, seasons and tea leaf maturity. The study also explored how different manufacturing processes affect the leaching of fluoride into tea beverages. The fluoride concentration in the tea leaves was significantly correlate to the concentration of water-soluble fluoride in the soil. Different tea varieties accumulated different levels of fluoride, with varieties, Anji baicha having the highest and Nongkang zao having the lowest fluoride concentration. In eight different varieties of tea plant harvested over three tea seasons, fluoride concentration were highest in the summer and lowest in the spring in china. The fluoride concentration in tea leaves was directly related to the maturity of the tea leaves at harvest. Importantly, the tea manufacturing process did not introduced fluoride contamination. The leaching of fluoride was 6.8% and 14.1% higher in black and white tea, respectively, than in fresh tea leaves. The manufacturing step most affecting the leaching of fluoride into tea beverage was withering used in white, black and oolong tea rather than rolling or fermentation. The exposure and associated health risks for fluoride concentration in infusions of 115 commercially available teas from Chinese tea markets was determined. The fluoride concentration ranged from 5.0 to 306.0mgkg(-1), with an average of 81.7mgkg(-1). The hazard quotient (HQ) of these teas indicated that there was no risk of fluorosis from drinking tea, based on statistical analysis by Monte Carlo simulation.


Assuntos
Camellia sinensis/química , Fluoretos/análise , Folhas de Planta/química , Chá/química , Camellia sinensis/crescimento & desenvolvimento , China , Manipulação de Alimentos , Humanos , Método de Monte Carlo , Medição de Risco , Estações do Ano , Solo/química , Chá/efeitos adversos
12.
Int J Mol Sci ; 17(7)2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27428960

RESUMO

Tea (Camellia sinensis L.) is recalcitrant to Agrobacterium-mediated genetic transformation largely due to the bactericidal effects of tea polyphenols and phenolics oxidation induced by necrosis of explant tissue over the process of transformation. In this study, different antioxidants/adsorbents were added as supplements to the co-cultivation and post co-cultivation media to overcome these problems for the transformation improvement. Tea-cotyledon-derived calli were used as explants and Agrobacterium rhizognes strain ATCC 15834 was used as a mediator. Results showed that Agrobacterium growth, virulence (vir) gene expression and browning of explant tissue were greatly influenced by different supplements. Murashige and Skoog (MS) basal salts medium supplemented with 30 g·L(-1) sucrose, 0.1 g·L(-1) l-glutamine and 5 g·L(-1) polyvinylpolypyrrolidone (PVPP) as co-cultivation and post co-cultivation media could maintain these parameters better that ultimately led to significant improvement of hairy root generation efficiency compared to that in the control (MS + 30 g·L(-1) sucrose). Additionally, the reporter genes ß-glucuronidase (gusA) and cyan fluorescent protein (cfp) were also stably expressed in the transgenic hairy roots. Our study would be helpful in establishing a feasible approach for tea biological studies and genetic improvement of tea varieties.


Assuntos
Agrobacterium/crescimento & desenvolvimento , Antioxidantes/farmacologia , Camellia sinensis/genética , Meios de Cultivo Condicionados/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Agrobacterium/efeitos dos fármacos , Agrobacterium/genética , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Transformação Genética
13.
Foods ; 13(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38472905

RESUMO

Green tea catechins (GTCs) are dietary polyphenols with broad bioactivities that undergo extensive microbial metabolism in the human gut. However, microbial-transferred metabolites and their health benefits are not fully understood. Herein, the microbial metabolism of GTCs by human fecal microbiota and dynamic alteration of the microbiota were integrally investigated via in vitro anaerobic fermentation. The results showed that the human gut microbiota exhibited a strong metabolic effect on GTCs via UHPLC-MS/MS analysis. A total of 35 microbial-transferred metabolites were identified, far more than were identified in previous studies. Among them, five metabolites, namely EGCG quinone, EGC quinone, ECG quinone, EC quinone, and mono-oxygenated EGCG, were identified for the first time in fermented GTCs with the human gut microbiota. Consequently, corresponding metabolic pathways were proposed. Notably, the antioxidant, α-amylase, and α-glucosidase inhibitory activities of the GTCs sample increased after fermentation compared to those of the initial unfermented sample. The results of the 16S rRNA gene sequence analysis showed that the GTCs significantly altered gut microbial diversity and enriched the abundancy of Eubacterium, Flavonifractor, etc., which may be further involved in the metabolisms of GTCs. Thus, these findings contribute to a better understanding of the interactions between GTCs and gut microbiota, as well as the health benefits of green tea consumption.

14.
Foods ; 13(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38890983

RESUMO

Metabolic syndrome (MetS) significantly predisposes individuals to diabetes and is a prognostic factor for the progression of diabetic nephropathy (DN). This study aimed to evaluate the efficacy of (-)-gallocatechin gallate (GCG) in alleviating signs of MetS-associated DN in db/db mice. We administered GCG and monitored its effects on several metabolic parameters, including food and water intake, urinary output, blood glucose levels, glucose and insulin homeostasis, lipid profiles, blood pressure, and renal function biomarkers. The main findings indicated that GCG intervention led to marked improvements in these metabolic indicators and renal function, signifying its potential in managing MetS and DN. Furthermore, transcriptome analysis revealed substantial modifications in gene expression, notably the downregulation of pro-inflammatory genes such as S100a8, S100a9, Cd44, Socs3, Mmp3, Mmp9, Nlrp3, IL-1ß, Osm, Ptgs2, and Lcn2 and the upregulation of the anti-oxidative gene Gstm3. These genetic alterations suggest significant effects on pathways related to inflammation and oxidative stress. In conclusion, GCG demonstrates therapeutic efficacy for MetS-associated DN, mitigating metabolic disturbances and enhancing renal health by modulating inflammatory and oxidative responses.

15.
J Hazard Mater ; 469: 134098, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38522198

RESUMO

To investigate the efficacy of epigallocatechin gallate (EGCG) and its underlying mechanism in preventing bisphenol-A-induced metabolic disorders, in this study, a mice model of metabolic disorders induced by BPA was developed to investigate the efficacy and mechanism of EGCG using microbiomes and metabolomics. The results showed that EGCG reduced body weight, liver weight ratio, and triglyceride and total cholesterol levels in mice by decreasing the mRNA expression of genes related to fatty acid synthesis (Elov16) and cholesterol synthesis (CYP4A14) and increasing the mRNA expression of genes related to fatty acid oxidation (Lss) and cholesterol metabolism (Cyp7a1). In addition, EGCG normalized BPA-induced intestinal microbial dysbiosis. Metabolic pathway analysis showed that low-dose EGCG was more effective than high-dose EGCG at affecting the biosynthesis of L-cysteine, glycerophosphorylcholine, and palmitoleic acid. These results provide specific data and a theoretical basis for the risk assessment of BPA and the utilization of EGCG.


Assuntos
Compostos Benzidrílicos , Catequina/análogos & derivados , Doenças Metabólicas , Fenóis , Camundongos , Animais , Colesterol , RNA Mensageiro , Ácidos Graxos
16.
Phytomedicine ; 133: 155919, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39153277

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is a major clinical and global public health issue, with no specific pharmacological treatment available. Currently, there is a lack of approved drugs for the clinical treatment of NAFLD. Large-leaf yellow tea polysaccharides (YTP) is a natural biomacromolecule with excellent prebiotic properties and significant therapeutic effects on multiple metabolic diseases. However, the specific mechanisms by which YTP regulates NAFLD remain unclear. PURPOSE: This study aims to explore the prebiotic effects of YTP and the potential mechanisms by which it inhibits hepatic cholesterol accumulation in NAFLD mice. METHODS: The effects of YTP on lipid accumulation were evaluated in NAFLD mice through obesity trait analysis and bile acids (BAs) metabolism assessment. Additionally, fecal microbiota transplantation (FMT) was performed, and high-throughput sequencing was employed to investigate the mechanisms underlying YTP's regulatory effects on gut microbiota and BA metabolism. RESULTS: Our study demonstrated that YTP altered the constitution of colonic BA, particularly increasing the levels of conjugated BA and non-12OH BA, which suppressed ileum FXR receptors and hepatic BA reabsorption, facilitated BA synthesis, and fecal BA excretion. The modifications were characterized by a decrease in the levels of FXR, FGF15, FGFR4, and ASBT proteins, and an increase in the levels of Cyp7a1 and Cyp27a1 proteins. YTP might affect enterohepatic circulation and by the activated the hepatic FXR-SHP pathway. Meanwhile, YTP reshaped the intestinal microbiome structure by decreasing BSH-producing genera and increasing taurine metabolism genera. The correlation analysis implied that Muribaculaceae, Pseudomonas, acterium_coprostanoligenes_group, Clostridiales, Lachnospiraceae_NK4A136_group, Delftia, Dubosiella, and Romboutsia were strongly correlated with specific BA monomers. CONCLUSIONS: YTP modulates bile salt hydrolase-related microbial genera to activate alternative bile acid synthesis pathways, thereby inhibiting NAFLD progression. These results suggest that YTP may serve as a potential probiotic formulation, offering a feasible dietary intervention for NAFLD.


Assuntos
Ácidos e Sais Biliares , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Polissacarídeos , Chá , Animais , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Ácidos e Sais Biliares/metabolismo , Polissacarídeos/farmacologia , Masculino , Camundongos , Chá/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Prebióticos , Fatores de Crescimento de Fibroblastos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Amidoidrolases/metabolismo
17.
Food Chem ; 456: 139936, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38865822

RESUMO

Large-leaf yellow tea (LYT)-derived peptides (TPP) are rich in amino acids required for damage repair, such as Glu, Arg, and Pro, and can be used to alleviate acute colitis. However, its effect and mechanisms against colitis remain unclear. This study utilized TPP to intervene in dextran sodium sulfate-induced acute colitis in C57BL/6 J mice. Results confirmed that TPP ameliorated acute colitis symptoms by inhibiting pro-inflammatory cytokines, restoring gut microbiota dysbiosis, particularly by increasing the abundance of beneficial bacteria Akkermansia and Lactobacillus while declining harmful microbiota Escherichia-Shigella. Besides, TPP intervention reshaped the gut microbiota phenotype by increasing the aerobic phenotype and reducing the potentially pathogenic phenotype. Levels of short-chain fatty acids, including acetic acid, propanoic acid, isobutyric acid, and butyric acid, were also enhanced in a dose-dependent manner to help restore gut microbiota equilibrium. This study supports using TPP as a viable plant protein-derived dietary resource for alleviating inflammatory bowel disease.


Assuntos
Colite , Sulfato de Dextrana , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Peptídeos , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/microbiologia , Sulfato de Dextrana/efeitos adversos , Camundongos , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Peptídeos/química , Masculino , Humanos , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Proteínas de Plantas/química , Proteínas de Plantas/administração & dosagem , Chá/química , Camellia sinensis/química , Modelos Animais de Doenças
18.
Food Sci Nutr ; 12(2): 776-785, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38370081

RESUMO

Dietary habits and exercise play an important role in the well-being of human health. Currently, how long of drinking tea combined with exercise could efficiently ameliorate hepatic steatosis and obesity still needs to be investigated. Here, short-term and long-term green tea drinking combined with exercise were studied to improve hepatic steatosis and obesity in high-fat diet-induced (HF) mice. Our results showed that Yunkang 10 green tea (GT) combined with exercise (Ex) exhibited synergistic prevention effects on ameliorating hepatic steatosis and obesity. Especially, 22-week intervention with GT or Ex improved all symptoms of obesity, which indicated that long-term intervention exhibited profound preventive effects than the short term. Moreover, the combined intervention of 22 weeks inhibited the activation of NF-κB pathway and the expression of proinflammatory cytokines, which suggests that tea combined exercise may improve liver steatosis mainly by inhibiting inflammation. The key molecules for regulating lipid and glucose metabolism SCD1 were obviously downregulated, and GLU2 and PPARγ were significantly upregulated by GT and exercise in the liver of high-fat diet-induced mice. This study demonstrated that long-term intervention with GT and exercise effectively relieved hepatic steatosis and obesity complications by ameliorating hepatic inflammation, reducing lipid synthesis, and accelerating glucose transport.

19.
Foods ; 13(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39272601

RESUMO

This study investigated the effects of various characteristic components of tea-theaflavins, catechins, thearubigins, theasinensins, theanine, catechin (C), catechin gallate (CG), epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallocatechin (GC), and gallocatechin gallate (GCG)-on acrylamide formation. The results revealed that most of tea's characteristic components could significantly eliminate acrylamide, ranked from highest to lowest as follows: GC (55.73%) > EC (46.31%) > theaflavins (44.91%) > CG (40.73%) > thearubigins (37.36%) > ECG (37.03%) > EGCG (27.37%) > theabrownine (22.54%) > GCG (16.21%) > catechins (10.14%) > C (7.48%). Synergistic elimination effects were observed with thearubigins + EC + GC + CG, thearubigins + EC + CG, thearubigins + EC + GC, theaflavins + GC + CG, and thearubigins + theaflavins, with the reduction rates being 73.99%, 72.67%, 67.62%, 71.03%, and 65.74%, respectively. Tea's components reduced the numbers of persistent free radicals to prevent acrylamide formation in the model system. The results provide a theoretical basis for the development of low-acrylamide foods and the application of tea resources in the food industry.

20.
J Control Release ; 374: 39-49, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39111597

RESUMO

Immunological adjuvants are vaccine components that enhance long-lasting adaptive immune responses to weakly immunogenic antigens. Monophosphoryl lipid A (MPLA) is a potent and safe vaccine adjuvant that initiates an early innate immune response by binding to the Toll-like receptor 4 (TLR4). Importantly, the binding and recognition process is highly dependent on the monomeric state of MPLA. However, current vaccine delivery systems often prioritize improving the loading efficiency of MPLA, while neglecting the need to maintain its monomeric form for optimal immune activation. Here, we introduce a Pickering emulsion-guided MPLA monomeric delivery system (PMMS), which embed MPLA into the oil-water interface to achieve the monomeric loading of MPLA. During interactions with antigen-presenting cells, PMMS functions as a chaperone for MPLA, facilitating efficient recognition by TLR4 regardless of the presence of lipopolysaccharide-binding proteins. At the injection site, PMMS efficiently elicited local immune responses, subsequently promoting the migration of antigen-internalized dendritic cells to the lymph nodes. Within the draining lymph nodes, PMMS enhanced antigen presentation and maturation of dendritic cells. In C57BL/6 mice models, PMMS vaccination provoked potent antigen-specific CD8+ T cell-based immune responses. Additionally, PMMS demonstrated strong anti-tumor effects against E.G7-OVA lymphoma. These data indicate that PMMS provides a straightforward and efficient strategy for delivering monomeric MPLA to achieve robust cellular immune responses and effective cancer immunotherapy.

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