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Antibacterial mechanism of kojic acid and tea polyphenols against Escherichia coli O157:H7 through transcriptomic analysis 被引量:1
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作者 Yilin Lin Ruifei Wang +4 位作者 Xiaoqing Li Keren Agyekumwaa Addo Meimei Fang Yehui Zhang Yigang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期736-747,共12页
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag... Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry. 展开更多
关键词 Kojic acid tea polyphenols Antibacterial mechanism Escherichia coli O157:H7 RNA-SEQ
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The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model
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作者 Ruonan Yan Chi-Tang Ho +3 位作者 Yanan Liu Shengnan Zhan Zufang Wu Xin Zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期748-764,共17页
The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)impro... The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state imbalance.After fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic cells.Our results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health. 展开更多
关键词 Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism
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Tea Polyphenols Reduce Inflammation of Orbital Fibroblasts in Graves’Ophthalmopathy via the NF-κB/NLRP3 Pathway 被引量:1
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作者 Wei LIU Chao MA +2 位作者 Hao-yu LI Shan-si YUAN Kai-jun LI 《Current Medical Science》 SCIE CAS 2023年第1期123-129,共7页
Objective:This study aimed to explore the effects of tea polyphenols(TP)on inflammation of orbital fibroblasts in Graves’ophthalmopathy(GO)and to provide new ideas for GO treatment.Methods:Primary orbital fibroblasts... Objective:This study aimed to explore the effects of tea polyphenols(TP)on inflammation of orbital fibroblasts in Graves’ophthalmopathy(GO)and to provide new ideas for GO treatment.Methods:Primary orbital fibroblasts were extracted from orbital adipose/connective tissues of patients with and without GO.Real-time quantitative PCR(RT-qPCR)was used to detect the expression of interleukin(IL)-6,IL-1β,and monocyte chemotactic protein(MCP)-1 in non-GO and GO orbital fibroblasts.The CCK-8 assay was used to determine the appropriate concentration of TP for subsequent experiments.RT-qPCR and enzyme-linked immunosorbent assay(ELISA)were performed to investigate the effects of TP on lipopolysaccharide(LPS)-induced production of inflammatory cytokines.Nuclear factor-κB(NF-κB)expression was measured using Western blotting analysis.NOD-like receptor 3(NLRP3)expression was detected using both Western blotting analysis and immunofluorescence staining.Results:The mRNA levels of IL-6,IL-1β,and MCP-1 in GO orbital fibroblasts were significantly higher than those in non-GO cells.TP treatment significantly inhibited LPS-induced production of inflammatory factors,including IL-6,IL-1β,and MCP-1.TP also inhibited the expression levels of NF-κB and NLRP3.Inflammation in the GO orbital fibroblasts was higher than that in non-GO cells.TP inhibited the production of inflammatory cytokines in GO orbital fibroblasts in vitro through the NF-κB/NLRP3 pathway.Conclusion:These findings suggest that TP may have a potential role in GO treatment. 展开更多
关键词 tea polyphenols Graves’ophthalmopathy INFLAMMATION
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Plant-inspired biomimetic hybrid PVDF membrane co-deposited by tea polyphenols and 3-amino-propyl-triethoxysilane for high-efficiency oilin-water emulsion separation
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作者 Lijian Shi Yaping Zhang +2 位作者 Yujia Tong Wenlong Ding Weixing Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期170-180,共11页
Membrane pollution caused by separating oily wastewater is a big challenge for membrane separation technology.Recently,plant-/mussel-inspired interface chemistry has received more and more attention.Herein,a high anti... Membrane pollution caused by separating oily wastewater is a big challenge for membrane separation technology.Recently,plant-/mussel-inspired interface chemistry has received more and more attention.Herein,a high antifouling poly(vinylidene fluoride)(PVDF)membrane,coated with tea polyphenols(TP,extracted from green tea)and 3-amino-propyl-triethoxysilane(APTES),was developed to purify oil-inwater emulsions.ATR-FTIR,XPS and SEM were used to demonstrate the evolution of surface biomimetic hybrid coatings.The performances of the developed membranes were investigated by pure water permeability and oil rejection for various surfactant-stabilized oil-in-water emulsions.The experimental results revealed that the membrane deposited with a mass ratio of 0.1/0.2 exhibited ultrahigh pure water permeability(14570 L·m^(-2)·h^(-1)·bar^(-1),1 bar=0.1 MPa)and isooctane-in-water emulsion permeability(5391 L·m^(-2)·h^(-1)·bar^(-1))with high separation efficiency(>98.9%).Even treated in harsh environment(acidic,alkaline and saline)for seven days,the membrane still maintained considerable underwater oleophobic property(148°–153°).The fabricated plant-inspired biomimetic hybrid membranes with excellent performances light a broad application prospect in the field of oily wastewater treatment. 展开更多
关键词 Plant-inspired chemistry Hierarchical nanoparticles tea polyphenols Anti-oil adhesion Acid-base-salt resistance
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Green tea polyphenols alleviate di-(2-ethylhexyl)phthalate-induced liver injury in mice
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作者 Heng Shi Xin-Hai Zhao +6 位作者 Qin Peng Xian-Ling Zhou Si-Si Liu Chuan-Chuan Sun Qiu-Yu Cao Shi-Ping Zhu Sheng-Yun Sun 《World Journal of Gastroenterology》 SCIE CAS 2023年第34期5054-5074,共21页
BACKGROUND Di(2-ethylhexyl)phthalate(DEHP)is a common plasticizer known to cause liver injury.Green tea is reported to exert therapeutic effects on heavy metal exposureinduced organ damage.However,limited studies have... BACKGROUND Di(2-ethylhexyl)phthalate(DEHP)is a common plasticizer known to cause liver injury.Green tea is reported to exert therapeutic effects on heavy metal exposureinduced organ damage.However,limited studies have examined the therapeutic effects of green tea polyphenols(GTPs)on DEHP-induced liver damage.AIM To evaluate the molecular mechanism underlying the therapeutic effects of GTPs on DEHP-induced liver damage.METHODS C57BL/6J mice were divided into the following five groups:Control,model[DEHP(1500 mg/kg bodyweight)],treatment[DEHP(1500 mg/kg bodyweight)+GTP(70 mg/kg bodyweight),oil,and GTP(70 mg/kg bodyweight)]groups.After 8 wk,the liver function,blood lipid profile,and liver histopathology were examined.Differentially expressed micro RNAs(miRNAs)and mRNAs in the liver tissues were examined using high-throughput sequencing.Additionally,functional enrichment analysis and immune infiltration prediction were performed.The miRNA-mRNA regulatory axis was elucidated using the starBase database.Protein expression was evaluated using immunohistochemistry.RESULTS GTPs alleviated DHEP-induced liver dysfunction,blood lipid dysregulation,fatty liver disease,liver fibrosis,and mitochondrial and endoplasmic reticulum lesions in mice.The infiltration of macrophages,mast cells,and natural killer cells varied between the model and treatment groups.mmu-miR-141-3p(a differentially expressed miRNA),Zcchc24(a differentially expressed mRNA),and Zcchc24(a differentially expressed protein)constituted the miRNA-mRNA-protein regulatory axis involved in mediating the therapeutic effects of GTPs on DEHP-induced liver damage in mice.CONCLUSION This study demonstrated that GTPs mitigate DEHP-induced liver dysfunction,blood lipid dysregulation,fatty liver disease,and partial liver fibrosis,and regulate immune cell infiltration.Additionally,an important miRNAmRNA-protein molecular regulatory axis involved in mediating the therapeutic effects of GTPs on DEHP-induced liver damage was elucidated. 展开更多
关键词 Green tea polyphenols Di(2-ethylhexyl)phthalate Liver fibrosis Fatty liver disease MITOCHONDRIA IMMUNE
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Preparation and Drug-Release Property of Polycaprolactone (PCL)/Polyglycolic Acid (PGA) Composite Masterbatch with Drug of Tea Polyphenols (TPs)
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作者 吴改红 刘淑强 +6 位作者 杨雅茹 莫易涵 李杰特 李静静 张菂 杨智超 陆东东 《Journal of Donghua University(English Edition)》 CAS 2023年第3期277-283,共7页
In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medic... In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medical textiles.The surface morphology and the chemical structure of the masterbatches were analyzed.The crystallization,mass losses,strengths and drug-release rates of the composite masterbatches at different PCL/PGA mass ratios were explored.The results show that the degradation rate of the PGA carrier is obvious higher than that of the PCL carrier,and PCL,PGA and the tea polyphenol(TP) drug just physically mix without chemical reaction.During the degradation,the strength of the composite masterbatches gradually decreases.In addition,the drug-release rates of composite masterbatches at different mass ratios are different,and the more the PGA in the composite masterbatches,the faster the drug release of the composite masterbatches.The drug-release rate of the composite masterbatches can be controlled by adjusting the contents of PCL and PGA. 展开更多
关键词 polycaprolactone(PCL) polyglycolic acid(PGA) tea polyphenol(TP) composite masterbatch drug release
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Research Progress on the Therapeutic Mechanism of Tea Polyphenols in Neurodegenerative Diseases
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作者 Zhenying Yu Hongyan Wu 《Journal of Biosciences and Medicines》 2023年第11期65-75,共11页
In recent years, the incidence of neurodegenerative diseases, mainly Alzheimer’s disease, Parkinson’s disease, vascular dementia, and cerebral ischemia, has been rising gradually, which has a serious impact on the p... In recent years, the incidence of neurodegenerative diseases, mainly Alzheimer’s disease, Parkinson’s disease, vascular dementia, and cerebral ischemia, has been rising gradually, which has a serious impact on the physiological state and quality of life of human beings in old age, and the current clinical drugs are unsatisfactory in terms of therapeutic efficacy and healing, which has made this kind of diseases become a social medical problem. Tea polyphenols are the main functional components of tea and have great potential in neuroprotection. In this paper, we review the research on tea polyphenols in neurodegenerative diseases, with the aim of providing a new entry point for the treatment of neurodegenerative diseases. 展开更多
关键词 Neurodegenerative Diseases tea polyphenols NEUROPROTECTION
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A review of pharmacological activity and application potential in food of tea polyphenols
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作者 Zhan Li Wang Li +3 位作者 Zhi-Yong Liang Xian-Jun Liu Hao Li Zhan-Dong Li 《TMR Pharmacology Research》 2023年第1期3-13,共11页
Tea polyphenols(TP)is a class of polyhydroxy compounds isolated from tea.Modern biological and medical studies have shown that TP has many pharmacological activities,such as anti-inflammatory,anti-virus,anti-oxidation... Tea polyphenols(TP)is a class of polyhydroxy compounds isolated from tea.Modern biological and medical studies have shown that TP has many pharmacological activities,such as anti-inflammatory,anti-virus,anti-oxidation,anti-tumor and anti-radiation.Furthermore,these substances can be used as a potential drug component to positively guide the occurrence and development of certain diseases.Furthermore,because of the activities of TP,such as anti-oxidation and anti-bacteria,it can be applied in food preservation,color preservation,deodorization,and treatment of food processing by-products.Based on the research progress of TP in recent years,this paper summarizes the pharmacological activities of TP and expounds on its application potential in the field of food.In order to provide a theoretical reference for the research,development and utilization of TP. 展开更多
关键词 tea polyphenols pharmacological activities FOOD application potential
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Protective Effects of Tea Polyphenol on Cerebral Ischemia-Reperfusion Injury in Rats and Its Scavenging Oxy-radical and Anticerebral Lipid Peroxidation Effects 被引量:11
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作者 何冰 陈小夏 陈一岳 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期157-161,共5页
AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cer... AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant. 展开更多
关键词 tea polyphenol Scavenging oxygen free redicals Antilipid peroxidation Ischemia reperfusion
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A novel long-chain acyl-derivative of epigallocatechin-3-O-gallate prepared and purified from green tea polyphenols 被引量:3
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作者 陈平 谭曜 +1 位作者 孙东 郑小明 《Journal of Zhejiang University Science》 CSCD 2003年第6期714-718,共5页
Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long chain acyl derivative of epigallocatechin 3 o gallate (EGCG) ... Lipophilic tea polyphenols (LTP) were prepared by catalytic esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long chain acyl derivative of epigallocatechin 3 o gallate (EGCG) was first isolated from purification of LTP by high speed countercurrent chromatography (HSCCC) using a solvent system composed of n hexane ethyl acetate methanol water (1:1:1:1, v/v). The molecular structure of the acyl derivative, Epigallocatechin 3 O gallate 4′ O hexadecanate , was elucidated by means of elemental analysis, IR, 1H NMR and MS spectra. 展开更多
关键词 Green tea polyphenols Lipophilic tea polyphenols Epigallocatechin-3-O-gallate Epigallocatechin-3-O-gallate-4′-O-hexadecanate Isolation High-speed countercurrent chromatography
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Regulatory Mechanism of Tea Polyphenols on Heat Stress in Animals 被引量:2
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作者 周伟光 刘龙洲 +1 位作者 薛波 杨烨 《Agricultural Science & Technology》 CAS 2016年第5期1211-1213,共3页
Teapolyphenols are the generic term of polyphenols in tea.Tea polyphenols are non-toxic and odorless with high oxidation resistance.Heat stress causes oxidative stress,which impairs the capacity of antioxidant defense... Teapolyphenols are the generic term of polyphenols in tea.Tea polyphenols are non-toxic and odorless with high oxidation resistance.Heat stress causes oxidative stress,which impairs the capacity of antioxidant defense system and immunity,thereby seriously affecting the production performance of animals.Teapolyphenols could reduce heatstress response in animals by scavenging harmful free radicals and increasing the activities of antioxidant enzymes. 展开更多
关键词 tea polyphenols Heat stress Oxidative stress Regulatory mechanism
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ROS-related Enzyme Expressions in Endothelial Cells Regulated by Tea Polyphenols 被引量:12
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作者 CHEN-JIANGYING XIU-FASUN +4 位作者 SHU-LINZHANG XI-PINGZHANG LI-MEIMAO XUE-ZHIZUO PINGYAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第1期33-39,共7页
Objective Elevation of reactive oxygen species (ROS), especially the level of superoxide is a key event in many forms of cardiovascular diseases. To study the mechanism of tea polyphenols against cardiovascular diseas... Objective Elevation of reactive oxygen species (ROS), especially the level of superoxide is a key event in many forms of cardiovascular diseases. To study the mechanism of tea polyphenols against cardiovascular diseases, we observed the expressions of ROS-related enzymes in endothelial cells. Methods Tea polyphenols were co-incubated with bovine carotid artery endothelial cells (BCAECs) in vitro and intracellular NADPH oxidase subunits p22phox and p67phox, SOD-1, and catalase protein were detected using Western blot method. Results Tea polyphenols of 0.4 ug/mL and 4.0 ug/mL (from either green tea or black tea) down-regulated NADPH oxidase p22phox and p67phox expressions in a dose-negative manner (P<0.05), and up-regulated the expressions of catalase (P<0.05). Conclusions Tea polyphenols regulate the enzymes involved in ROS production and elimination in endothelial cells, and may be beneficial to the prevention of endothelial cell dysfunction and the development of cardiovascular diseases. 展开更多
关键词 tea polyphenols Endothelial cells NADPH oxidase CATALASE Western blot
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Green tea polyphenols ameliorate non-alcoholic fatty liver disease through upregulating AMPK activation in high fat fed Zucker fatty rats 被引量:11
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作者 Yi Tan Jane Kim +7 位作者 Jing Cheng Madeleine Ong Wei-Guo Lao Xing-Liang Jin Yi-Guang Lin Linda Xiao Xue-Qiong Zhu Xian-Qin Qu 《World Journal of Gastroenterology》 SCIE CAS 2017年第21期3805-3814,共10页
AIM To investigate protective effects and molecular mechanisms of green tea polyphenols(GTP) on nonalcoholic fatty liver disease(NAFLD) in Zucker fatty(ZF) rats.METHODS Male ZF rats were fed a high-fat diet(HFD) for 2... AIM To investigate protective effects and molecular mechanisms of green tea polyphenols(GTP) on nonalcoholic fatty liver disease(NAFLD) in Zucker fatty(ZF) rats.METHODS Male ZF rats were fed a high-fat diet(HFD) for 2 wk then treated with GTP(200 mg/kg) or saline(5 m L/kg) for 8 wk, with Zucker lean rat as their control. At the end of experiment, serum and liver tissue were collected for measurement of metabolic parameters, alanine aminotransferase(ALT) and aspartate aminotransferase(AST), inflammatory cytokines and hepatic triglyceride and liver histology. Immunoblotting was used to detect phosphorylation of AMP-activated protein kinase(AMPK) acetyl-Co A carboxylase(ACC), and sterol regulatory element-binding protein 1c(SREBP1c). RESULTS Genetically obese ZF rats on a HFD presented with metabolic features of hepatic pathological changes comparable to human with NAFLD. GTP intervention decreased weight gain(10.1%, P = 0.052) and significantly lowered visceral fat(31.0%, P < 0.01). Compared with ZF-controls, GTP treatment significantly reduced fasting serum insulin, glucose and lipids levels. Reduction in serum ALT and AST levels(both P < 0.01) were observed in GTP-treated ZF rats. GTP treatment also attenuated the elevated TNFα and IL-6 in the circulation. The increased hepatic TG accumulation and cytoplasmic lipid droplet were attenuated by GTP treatment, associated with significantly increased expression of AMPK-Thr172(P < 0.05) and phosphorylated ACC and SREBP1c(both P < 0.05), indicating diminished hepatic lipogenesis and triglycerides out flux from liver in GTP treated rats. CONCLUSION The protective effects of GTP against HFD-induced NAFLD in genetically obese ZF rats are positively correlated to reduction in hepatic lipogenesis through upregulating the AMPK pathway. 展开更多
关键词 Non-alcoholic fatty liver disease Green tea polyphenols Hepatic lipogenesis Inflammatory cytokines AMP-activated protein kinase
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Protective effect of tea polyphenols against paracetamol-induced hepatotoxicity in mice is significanly correlated with cytochrome P450 suppression 被引量:13
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作者 Xia Chen Chang-Kai Sun Guo-Zhu Han Jin-Yong Peng Ying Li Yan-Xia Liu Yuan-Yuan Lv Ke-Xin Liu Qin Zhou Hui-Jun Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第15期1829-1835,共7页
AIM: To investigate the hepatoprotective activity of tea polyphenols (TP) and its relation with cytochrome P450 (CYP450) expression in mice. METHODS: Hepatic CYP450 and CYPbs levels were measured by UV-spectroph... AIM: To investigate the hepatoprotective activity of tea polyphenols (TP) and its relation with cytochrome P450 (CYP450) expression in mice. METHODS: Hepatic CYP450 and CYPbs levels were measured by UV-spectrophotometry in mice 2 d after intraperitoneal TP (25, 50 and 100 mg/kg per day). Then the mice were intragastricly pre-treated with TP (100, 200 and 400 mg/kg per day) for six days before paracetamol (1000 mg/kg) was given. Their acute mortality was compared with that of control mice. The mice were pre-treated with TP (100, 200, and 400 mg/kg per day) for five days before paracetamol (500 mg/kg) was given. Hepatic CYP2E1 and CYPIA2 protein and mRNA expression levels were evaluated by Western blotting, immunohistochemical staining and transcriptase-polymerase chain reaction. RESULTS: The hepatic CYP450 and CYPb5 levels in mice of TP-treated groups (100, 200 and 400 mg/kg per day) were decreased in a dose-dependent manner compared with those in the negative control mice.TP significantly attenuated the paracetamol-induced hepatic injury and dramatically reduced the mortality of paracetamol-treated mice. Furthermore, TP reduced CYP2E1 and CYPIA2 expression at both protein and mRNA levels in a dose-dependent manner. CONCLUSION: TP possess potential hepatoprotective properties and can suppress CYP450 expression. 展开更多
关键词 tea polyphenols Cytochrome P450 Paracetamol-induced hepatotoxicity
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Antioxidant and anti-inflammatory roles of tea polyphenols in inflammatory bowel diseases 被引量:14
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作者 Van-Long Truong Woo-Sik Jeong 《Food Science and Human Wellness》 SCIE 2022年第3期502-511,共10页
Polyphenols,including phenolic acids,flavonoids,and procyanidins,are abundant in food and beverage derived from plants.Tea(Camellia sinensis)is particularly rich in polyphenols(e.g.,catechins,theaflavins,thearubigins,... Polyphenols,including phenolic acids,flavonoids,and procyanidins,are abundant in food and beverage derived from plants.Tea(Camellia sinensis)is particularly rich in polyphenols(e.g.,catechins,theaflavins,thearubigins,gallic acid,and flavonols),which are thought to contribute to the health benefits of tea.High intake of tea polyphenols has been described to prevent and/or attenuate a variety of chronic pathological conditions like cardiovascular diseases,neurodegenerative diseases,diabetes,and cancer.This review focuses on established antioxidant and anti-inflammatory properties of tea polyphenols and underlying mechanisms of their involvement in inflammatory bowel diseases(IBD).Tea polyphenols act as efficient antioxidants by inducing an endogenous antioxidant defense system and maintaining intracellular redox homeostasis.Tea polyphenols also regulate signaling pathways such as nuclear factor-κB,activator protein 1,signal transducer and activator of transcriptions,and nuclear factor E2-related factor 2,which are associated with IBD development.Accumulating pieces of evidence have indicated that tea polyphenols enhance epithelial barrier function and improve gut microbial dysbiosis,contributing to the management of inflammatory colitis.Therefore,this study suggests that supplementation of tea polyphenols could prevent inflammatory conditions and improve the outcome of patients with IBD. 展开更多
关键词 ANTIOXIDANT ANTI-INFLAMMATION Epithelial barrier function Inflammatory bowel diseases Gut microbiota tea polyphenols
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Tea polyphenols and their chemopreventive and therapeutic effects on colorectal cancer 被引量:8
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作者 Shi-Tong Wang Wen-Qi Cui +3 位作者 Dan Pan Min Jiang Bing Chang Li-Xuan Sang 《World Journal of Gastroenterology》 SCIE CAS 2020年第6期562-597,共36页
Colorectal cancer(CRC),a multifactorial disease,is usually induced and developed through complex mechanisms,including impact of diet and lifestyle,genomic abnormalities,change of signaling pathways,inflammatory respon... Colorectal cancer(CRC),a multifactorial disease,is usually induced and developed through complex mechanisms,including impact of diet and lifestyle,genomic abnormalities,change of signaling pathways,inflammatory response,oxidation stress,dysbiosis,and so on.As natural polyphenolic phytochemicals that exist primarily in tea,tea polyphenols(TPs)have been shown to have many clinical applications,especially as anticancer agents.Most animal studies and epidemiological studies have demonstrated that TPs can prevent and treat CRC.TPs can inhibit the growth and metastasis of CRC by exerting the antiinflammatory,anti-oxidative or pro-oxidative,and pro-apoptotic effects,which are achieved by modulations at multiple levels.Many experiments have demonstrated that TPs can modulate several signaling pathways in cancer cells,including the mitogen-activated protein kinase pathway,phosphatidylinositol-3 kinase/Akt pathway,Wnt/β-catenin pathway,and 67 kDa laminin receptor pathway,to inhibit proliferation and promote cell apoptosis.In addition,novel studies have also suggested that TPs can prevent the growth and metastasis of CRC by modulating the composition of gut microbiota to improve immune system and decrease inflammatory responses.Molecular pathological epidemiology,a novel multidisciplinary investigation,has made great progress on CRC,and the further molecular pathological epidemiology research should be developed in the field of TPs and CRC.This review summarizes the existing in vitro and in vivo animal and human studies and potential mechanisms to examine the effects of tea polyphenols on CRC. 展开更多
关键词 tea polyphenols Colorectal cancer Gut microbiota Signal pathway ANTIINFLAMMATION MECHANISMS
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Extraction of Theanine from Waste Liquid of Tea Polyphenol Production in Aqueous Two-phase Systems with Cationic and Anionic Surfactants 被引量:8
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作者 张军伟 王艳 彭奇均 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期31-36,共6页
Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that ... Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-'. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine. 展开更多
关键词 aqueous two-phase system SURFACTANT THEANINE waste liquid of tea polyphenol production EXTRACTION
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Focusing on the recent progress of tea polyphenol chemistry and perspectives 被引量:12
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作者 Shiming Li Liang Zhang +2 位作者 Xiaochun Wan Jianfeng Zhan Chi-Tang Ho 《Food Science and Human Wellness》 SCIE 2022年第3期437-444,共8页
Myriad evidence attests to the health-promoting benefits of tea drinking.While there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable co... Myriad evidence attests to the health-promoting benefits of tea drinking.While there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable components.The chemical characterization and physical characteristics of tea polyphenols have been comprehensively studied over the previous years.Still the emergence of new chemistry in tea,particularly the property of scavenging reactive carbonyl species(RCS)and the newly discovered flavoalkaloid compounds,has drawn increasing attention.In this review,we summarize recent findings of a new class of compounds in tea-flavonoid alkaloids(flavoalkaloids),which exist in fresh tea leaves and can be generated during the process of post-harvesting,and also postulate the formation mechanism of flavoalkaloids between catechins and theanine-derived Strecker aldehyde.Additionally,we detail the up-to-date research results of tea polyphenols regarding their ability to trap RCS and their in vivo aminated metabolites to suppress advanced glycation ends products(AGEs).We further raise questions to be addressed in the near future,including the synthetic pathways for the generation of flavoalkaloids and AGEs in fresh tea leaves before processing and the concentrations of tea polyphenols that affect their RCS scavenging capability due to their pro-oxidant nature.More intensive research is warranted to elucidate the mechanisms of action underlying the biological activity of flavoalkaloids and the pharmacological application of tea polyphenols in scavenging RCS and impeding detrimental AGEs. 展开更多
关键词 tea chemistry Flavonoalkaloids RCS adducts Aminated tea polyphenols AGES
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Green tea polyphenols inhibit testosterone production in rat Leydig cells 被引量:4
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作者 Marina S. Figueiroa Juliany S. B. Cesar Vieira Disleide S. Leite Ruben C. O. Andrade Filho Fabiano Ferreira Patricia S. Gouveia Daniel P. Udrisar Maria I. Wanderley 《Asian Journal of Andrology》 SCIE CAS CSCD 2009年第3期362-370,共9页
This study investigated the acute effects of green tea extract (GTE) and its polyphenol constituents, (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin (EC), on basal and stimulated testosterone prod... This study investigated the acute effects of green tea extract (GTE) and its polyphenol constituents, (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin (EC), on basal and stimulated testosterone production by rat Leydig cells in vitro. Leydig cells purified in a Percoll gradient were incubated for 3 h with GTE, EGCG or EC and the testosterone precursor androstenedione, in the presence or absence of either protein kinase A (PKA) or protein kinase C (PKC) activators. The reversibility of the effect was studied by pretreating cells for 15 min with GTE or EGCG, allowing them to recover for 1 h and challenging them for 2 h with human chorionic gonadotropin (hCG), luteinizing hormone releasing hormone (LHRH), 22(R)-hydroxycholesterol or androstenedione. GTE and EGCG, but not EC, inhibited both basal and kinase-stimulated testosterone production. Under the pretreatment conditions, the inhibitory effect of the higher concentration of GTE/EGCG on hCG/LHRH-stimulated or 22(R)- hydroxycholesterol-induced testosterone production was maintained, whereas androstenedione-supported testosterone production returned to control levels. At the lower concentration of GTE/EGCG, the inhibitory effect of these polyphenols on 22(R)-hydroxycholesterol-supported testosterone production was reversed. The inhibitory effects of GTE may be explained by the action of its principal component, EGCG, and the presence of a gallate group in its structure seems important for its high efficacy in inhibiting testosterone production. The mechanisms underlying the effects of GTE and EGCG involve the inhibition of the PKA/PKC signalling pathways, as well as the inhibition of P450 side-chain cleavage enzyme and 17β-hydroxysteroid dehydrogenase function. 展开更多
关键词 green tea polyphenols Leydig cells protein kinase A protein kinase C TESTOSTERONE
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Improving the stability and bioavailability of tea polyphenols by encapsulations:a review 被引量:7
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作者 Zhiya Yin Ting Zheng +3 位作者 Chi-Tang Ho Qingrong Huang Qingli Wu Man Zhang 《Food Science and Human Wellness》 SCIE 2022年第3期537-556,共20页
Tea polyphenols(TPPs)have attracted significant research interest due to their health benefits.However,TPPs are sensitive to certain environmental and gastrointestinal conditions and their oral bioavailability was fou... Tea polyphenols(TPPs)have attracted significant research interest due to their health benefits.However,TPPs are sensitive to certain environmental and gastrointestinal conditions and their oral bioavailability was found to be very low.Delivery systems made of food-grade materials have been reported to improve the shelf-life,bioavailability and bioefficacy of TPPs.This review discusses the chemistry of TPPs;the setbacks of TPPs for application;and the strategies to counteract application limitations by rationally designing delivery systems.An overview of different formulations used to encapsulate TPPs is provided in this study,such as emulsion-based systems(liposome,nanoemulsion,double emulsion,and Pickering emulsion)and nano/microparticles-based systems(protein-based,carbohydrate-based,and bi-polymer based).In addition,the stability,bioavailability and bioactivities of encapsulated TPPs are evaluated by various in vitro and in vivo models.The current findings provide scientific insights in encapsulation approaches for the delivery of TPPs,which can be of great value to TPPs-fortified food products.Further explorations are needed for the encapsulated TPPs in terms of their applications in the real food industry as well as their biological fate and functional pathways in vivo. 展开更多
关键词 tea polyphenols ENCAPSULATION Stability BIOAVAILABILITY Bioefficacy
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