Article

Effect of Pu-erh Tea on Body Fat and Lipid Profiles in Rats with Diet-induced Obesity

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Abstract

The antiobesity and antihyperlipidaemic effects of pu-erh tea in rats with high fat diet (HFD)-induced obesity were investigated. Male Sprague-Dawley rats were randomly divided into five groups and fed varying diets for an 8-week period: control diet, HFD, and HFD supplemented with low, moderate or high doses of pu-erh tea extract (0.5 g, 2 g and 4 g/kg BW/day, respectively). Pu-erh tea significantly reduced the total body weight and the weight of various adipose pads. Pu-erh tea administration also significantly lowered plasma total cholesterol, triglyceride concentrations and low-density lipoprotein-cholesterol levels in rats with HFD-induced obesity, but did not affect high-density lipoprotein-cholesterol levels. Moreover, pu-erh tea significantly increased lipoprotein lipase, hepatic lipase and hormone-sensitive lipase activities in epididymal fat tissue in rats with HFD-induced obesity. Analysis of real-time reverse transcription-polymerase chain reaction results indicated that pu-erh tea significantly enhanced mRNA levels of hormone-sensitive lipase in rats with HFD-induced obesity. These results suggest that pu-erh tea attenuated visceral fat accumulation and improved hyperlipidemia in a rat model of HFD-induced obesity.

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... In recent decades, Pu-er tea, especially the ripe one, has attracted more and more attention, mainly due to its diverse catechin structure [2,3] and multiple health-promoting effects [4][5][6][7][8], as well as its special flavor and taste [9]. To date, more than 30 structures have been reported from Pu-er ripe teas produced in different areas, including two new cinchonain-type compounds, puerins A and B, as well as 8-oxo-caffeine and pyrimidines [3,10]. ...
... The 40-60% MeOH eluting fraction was further purified by a combination of CC with Toyopearl HW40C, MCI-gel CHP20P, Sephadex LH-20, Toyopearl HW40F, and semi-preparative HPLC to give four new compounds, 1-4. Four known flavan-3-ols (5)(6)(7)(8) were also determined as (+)-catechin (5) [12], (-)-epicatechin (6) [13], (±)gallocatechin (7) [14], and (-)-epigallocatechin (8) [14], by comparing directly with authentic samples and from their spectroscopic and physical data with literature values. In addition, the one-proton aromatic singlet at δ H 6.10 (1H, s, H-6) suggested the occurrence of a pentasubstituted A ring, and a two-proton aromatic singlet at δ H 6.38 (2H, s, H-2',6') revealed the presence of a 3,4,5-trihydroxylated B ring. ...
... The 40-60% MeOH eluting fraction was further purified by a combination of CC with Toyopearl HW40C, MCI-gel CHP20P, Sephadex LH-20, Toyopearl HW40F, and semi-preparative HPLC to give four new compounds, 1-4. Four known flavan-3-ols (5)(6)(7)(8) were also determined as (+)-catechin (5) [12], (-)-epicatechin (6) [13], (±)gallocatechin (7) [14], and (-)-epigallocatechin (8) [14], by comparing directly with authentic samples and from their spectroscopic and physical data with literature values. In addition, the one-proton aromatic singlet at δ H 6.10 (1H, s, H-6) suggested the occurrence of a pentasubstituted A ring, and a two-proton aromatic singlet at δ H 6.38 (2H, s, H-2',6') revealed the presence of a 3,4,5-trihydroxylated B ring. ...
Article
Pu-er ripe tea is a special microbial post-fermented tea made from Pu-er raw tea, a kind of green tea produced from the leaves of Camellia sinensis var. assamica. It is one of the most consumed teas in the past two decades in China, due to its special flavor, taste, and beneficial effects. This work aimed to obtain diverse catechin structures from Pu-er ripe tea, which led to the isolation of four new phenylpropanoid-substituted flavan-3-ols, puerins C-F (1-4), together with four known flavan-3-ols, (+)-catechin (5), (-)-epicatechin (6), (+/-)-gallocatechin (7), and (-)-epigallocatechin (8). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR, mass and CD spectra. Compounds 1-4, which could be formed in the post-fermentative process of Pu-er tea, were isolated for the first time from tea and Theaceae plant.
... One potential such therapy may lie in a long used traditional beverage produced in southwestern China known as Pu-erh tea. Pu-erh tea, a tea post-fermented by microorganisms [2] has long been consumed for its supposed benefits to health that are only recently being scientific explored, marked effects against oxidation [3][4][5], cancer [6], atherosclerosis [7], obesity [8,9], hypercholesterolemia, [10][11][12], among others. ...
... Despite great progress in both in vivo and in vitro researches into the effects of Pu-erh tea on human, rodents, and cells to ability to reduce body weight, fat mass, and the level of serum triglycerides, cholesterol, and low-density lipoproteins (LDL) while also inducing the level of high-density lipoproteins, and the progression of steatosis [7][8][9][13][14][15][16][17]. Unfortunately, the mechanisms by which Pu-erh tea consumption lowers body fat and lipid profiles is poorly understood. ...
... Decreased body weight gain [203] Salvia miltiorrhiza Tanshinone IIA Decreased body weight gain [195] Roots Glycyrrhiza glabra 18β-glycyrrhetinic acid, licochalcone A Decreased body weight gain, serum triglyceride and total cholesterol levels [197] [198] Vernonia amygdalina Decreased body weight gain [201] Pu-erh tea Decreased body weight gain, serum triglyceride and total cholesterol levels [202] Murraya koenigii Decreased body weight gain, serum triglyceride and total cholesterol levels [185] Houttuynia cordata Thunb. Decreased serum triglyceride levels [206] Nelumbo nucifera Gaertn. ...
... Its leaf powder was added to the diet of dietinduced obese rats for 4 weeks and resulted in a decrease of body weight gain, serum triacylglycerol, serum and brain total cholesterol; effects were stronger than by the antiobesity drug orlistat also tested in this study [201]. Administration of pu-erh tea in rats with high fat diet-induced obesity significantly reduced the total body weight, plasma total cholesterol, triglyceride concentrations and low-density lipoprotein-cholesterol, suggesting an attenuating effect on fat levels and accumulation [202]. ...
Article
Obesity is a global health threat. OECD reported that more than half (52%) of the adult population in the European Union is overweight or obese. Obesity and obesity-related co-morbidities have deep negative effects on morbidity, mortality, professional and personal quality of life. Health-care costs represent a negative impact of this disease, with an associated economic cost of 100 billion US$ per year in the United States. The most prescribed drugs for obesity treatment worldwide are orlistat, and phentermine/topiramate extended release, while the major prescribed drug for the same disease in the US are exenatide and dapagliflozin. The so far developed drugs, targeting weight loss, have a long history of malignant secondary effects. There is still a lack of efficient and safe drugs to treat obesity and related metabolic complications since in many cases cure cannot be reached by bariatric surgery or healthy lifestyle habits. Terrestrial and aquatic organisms are a promising source of valuable, bioactive compounds, often with interest for human health. Some of the natural compounds or organisms have been used for centuries by humans as traditional medicine foods. In this review, we give insights into the adipose tissue function and development, and the progress in traditional anti-obesity pharmacotherapy. A major focus is to highlight the state of the art of natural compounds with anti-obesity properties and their potential as candidates for drug development; an overview is given about natural compounds derived from different marine animal sources, cyanobacteria, marine phytoplankton, fungus or plants.
... One potential such therapy may lie in a long used traditional beverage produced in southwestern China known as Pu-erh tea. Pu-erh tea, a tea post-fermented by microorganisms [2] has long been consumed for its supposed benefits to health that are only recently being scientific explored, marked effects against oxidation [3][4][5], cancer [6], atherosclerosis [7], obesity [8,9], hypercholesterolemia, [10][11][12], among others. ...
... Despite great progress in both in vivo and in vitro researches into the effects of Pu-erh tea on human, rodents, and cells to ability to reduce body weight, fat mass, and the level of serum triglycerides, cholesterol, and low-density lipoproteins (LDL) while also inducing the level of high-density lipoproteins, and the progression of steatosis [7][8][9][13][14][15][16][17]. Unfortunately, the mechanisms by which Pu-erh tea consumption lowers body fat and lipid profiles is poorly understood. ...
Article
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Consumption of Pu-erh has been reported to result in numerous health benefits, but the mechanisms underlying purported weight-loss and lowering of lipid are poorly understood. Here, we used the nematode Caenorhaditis elegans to explore the water extract of Pu-erh tea (PTE) functions to reduce fat storage. We found that PTE down-regulates the expression of the master fat regulator SBP-1, a homologue of sterol regulatory element binding protein (SREBP) and its target stearoyl-CoA desaturase (SCD), a key enzyme in fat biosynthesis, leading to an increased ratio of stearic acid (C18:0) to oleic acid (C18:1n-9), and subsequently decreased fat storage. We also found that both the pharyngeal pumping rate and food uptake of C. elegans decreased with exposure to PTE. Collectively, these results provide an experimental basis for explaining the ability of Pu-erh tea in promoting inhibition of food uptake and the biosynthesis of fat via SBP-1 and SCD, thereby reducing fat storage.
... Compared with the results of previous studies, the inconsistency observed here might have been caused by the lower dose of OTPs or the shorter treatment time in our study. Most of the previous associated studies treated animals with Pu-erh tea extract for 8-12 weeks [27,28,30]. However, in our study, the rats were fed a high-fat diet containing OTPs for approximately 6 weeks. ...
... These results suggest that OTPs accelerated the metabolism of fatty acids in white adipose tissue. Previous studies have also found that consuming oolong tea (partially oxidized), black tea (full oxidized) and Pu-erh tea (oxidized and fermented) significantly decreased visceral fat levels without changing the body weight in mice [27,30]. These studies found that oolong tea, black tea and Puerh tea suppressed adiposity by activating AMPK. ...
Article
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Background Tea polyphenols are the prominent component in tea. After the fermentation process, tea polyphenols are oxidized by polyphenol oxidase to form oxidized tea polyphenols (OTPs). OTPs contain a significant amount of hydrophobic phenyl groups that can bind with non-aqueous materials. Here, we determined whether OTPs can bind with lipids and reduce fat uptake and assessed the effect of OTPs on decreasing obesity and alleviating hyperlipidaemia and other metabolic syndromes. Methods Rats were divided into three groups: control, high-fat diet (HFD) and OTP groups. The control and HFD groups were fed a chow diet and a high-fat diet, respectively, for 12 weeks; the OTP group was fed a high-fat diet for 6 weeks and then a high-fat diet containing 2 % OTP for 6 weeks. The serum and excrement triglyceride (TAG) and total cholesterol (CHOL) concentrations were determined, and liver tissue and white adipose tissue were collected to detect the expression levels of genes involved in lipid metabolism. Results Our results revealed that OTPs failed to decrease the serum concentrations of TAG and CHOL. OTPs alleviated the accumulation of lipids in the liver tissue and changed the expression levels of the regulators of lipid metabolism, i.e., peroxisome proliferation-activated receptors (ppars), compared with the rats fed a high-fat diet alone. We also observed a significantly decreased reduction of weight in the visceral white adipose, enhanced regulation of fatty acid β-oxidation by PPARα and enhanced biosynthesis of mitochondria in the visceral white adipose of the OTP rats compared with the HFD rats. Additionally, OTPs promoted the excretion of lipids. Conclusion Our results suggest that OTPs alleviate the accumulation of lipids in liver and visceral white adipose tissue and promote lipid excretion in rats in vivo.
... A review of the epidemiological literature some 8 years ago did identify tea (-)-epigallocatechin gallate as having antiobesity and antidiabetic activity but human health benefit was not generally conclusive [125]. One report, vide supra, using Pu'er tea as the intervention gave statistically significant reductions in many key variables such as the body mass index, waist-hip ratio, fasting serum glucose and lipoproteins [113], with similar indication from another group [114] and arrested visceral fat gain and lipidaemia in rats fed a high fat diet [126]. ...
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Directed against the global pandemic of inflammatory diseases, this group has outlined perspectives on possible health benefits of tea drinking or ingestion of tea extracts. Drawn from the scientific literature, this group has focussed mainly on Green Tea, Black (red) Tea, and Pu’er Tea but not herbal ‘tea'. This report has considered historical aspects of tea consumption, the chemical composition, principally polyphenols in their multifarious form e.g. catechins, dimers, thearubigens, etc. The focus has been on oxidative stress and related mechanisms and their impact on the incidence of obesity, metabolic syndrome, diabetes, and cardiovascular disease. The main outcome has been the amalgamation of evidence on mainly rodents and humans which generally indicate beneficial effects but as yet, despite the enormous work, potential functional foods based on tea products require further research.
... It is believed that the longer preservation period is better for the quality of pu-erh tea. These features of the tea differ greatly from those of green tea, which is unfermented and is preferably taken as fresh as possible, Some reports, including our previous study, showed that pu-erh tea has an hypolipidemic and antiobesity effects in rat [3][4][5] and human [6]. These ef-fects are the same as those caused by green tea and green tea catechins [7][8][9][10], though the total content of monomeric catechins in pu-erh tea leaves is low (ca. ...
Article
Pu-erh tea is one of post fermented tea manufactured through oxidative maturing by microorganisms. We investigated the preventive effects of pu-erh tea extract on oxazolone-induced type IV allergy in male (ICR) mice. Oral administra-tion of 50 mg/kg water extract of pu-erh tea leaves resulted in significant preventive effects against mouse type IV al-lergy. The hydrophilic Theabrownin-like fraction (TBW-ND), with a high molecular weight of approximately 12,000 or higher, was prepared from pu-erh tea leaves by a solvent-extraction method, followed by Diaion HP-20 column chro-matography and dialysis. Oral and percutaneous administrations of TBW-ND at doses of 18.7 mg/kg and 0.037 mg/ear also resulted in significant preventive effects, which included preventing increases in levels of the proinflammatory cytokine interleukin-12. The anti-allergic ingredients in TBW-ND were predicted to be highly complex compounds containing of polyphenols, polysaccharides and/or proteins. The results suggest pu-erh tea leaves could be a beneficial food for protecting against delayed-type allergy.
... Consumption of a calorie-rich diet results in lipid accumulation [24] excess production of inflammatory cytokines, and macrophage infiltration that favour the progression of liver disease [7]. [25] showed that high-fat diet could induce the hyperlipidemia in rats, and hyperlipidemia could alter the related marker enzyme profiles in serum and liver tissue and progress to liver cirrhosis [26, 27] have revealed that high fat diet promote hyperglycemia. [27] and its effect on muscle and liver physiology as well as endothelial function ...
Article
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Aim Sesamum indicum have been widely used in tradition medicine for thousand of year, it improves liver functions and provides protection against high fat fed metabolic rats. Present investigations were carried out on the hepatoprotective role of sesame meal treatment to high fat fed wistar rat. Healthy adult male wistar rats were divided into five groups. Group I: rats were fed a standard laboratory diet (20g/rat/day), Group II: rats were fed a high-fat diet alone (20mg/rat/day), Group III: rats were fed with combined mixture of 70% of high-fat diet with 30% sesame meal (20mg/rat/day), Group IV: rats were fed a high fat diet was administered with pioglitazone (25mg/kg of body weight) via intravenous in each day, Group V: rats were fed combined mixture of 70% standard laboratory pellet and 30% sesame meal (20mg/rat/day). The rats were sacrificed at the end of the experimental (thirteen week) period. High fat fed rat registered significantly increase in body weight and liver weight at the end of experimental period. The high fat fed rat substantially elevated its serum and liver tissue AST, ALT, ALP, bilirubin with decreased in total protein levels. Whereas the levels of all parameters significantly restored towards normalization by the sesame meal treatment. The results obtained suggest that the sesame meal have potent hepatoprotective action on high fat fed rats. A comparison of the performance in both sesame meal and pioglitazone treatment on high fat fed rat in respect of hepato-protective role is clearly indicate that the sesame meal treatment was more or less very equal to the result of pioglitazone as well as to the normal level.
... CHAPTER 5 Pu-erh Tea: Botany, Production, and Chemistry hypo-cholesterolemic effects, anti-obesity, anti-viral, anti-mutagenic, anti-microbial, anticarcinogenic, anti-diabetic, and neuro-protective effects (Jie et al., 2006;Duh et al., 2004;Qian et al., 2005;Sano et al., 1986;Kuo et al., 2005;Wang et al., 2008;Wang et al., 2010;Syu et al., 2008;Way et al., 2009;Cao et al., 2010;Chen et al., 2009;Gong et al., 2010;Zhang 2010). Pu-erh teas have also been found to prevent tooth decay and ulcers, control halitosis, cure stomach disorders, improve bacterial flora in the intestine, increase bone density, and protect against UV rays . ...
Chapter
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Pu-erh (pu'er) tea refers to processed leaves and buds of the broad-leaf variety of the tea plant (Camellia sinensis var. assamica (L.) O. Kuntze; Theaceae) primarily sourced from China's Yunnan province, as well as from neighboring areas of southwestern China (Sichuan, Guangxi and Guizhou provinces), Laos, Vietnam, Myanmar, Cambodia, and northeastern India. This region is the center of origin of the tea plant. It encompasses the hotspots of biodiversity in Indo-Burma and the mountains of Southwest China. The diverse habitats from where pu-erh tea is sourced results in a botanical product that is highly heterogeneous in terms of sensory profiles and morphological, phytochemical, and genetic variation. p0020 Along with environmental variability, the native tea-growing region is characterized by high cultural diversity and a range of tea production and consumption practices. Pu-erh may be processed as a loose or pressed green tea, or a post-fermented black tea. Green pu-erh has similar health claims to other green teas, while aged green pu-erh and post-fermented black pu-erh have additional health claims unique to fermented foods and beverages. Numerous socio-linguistic groups in the native tea-growing region have produced and consumed pu-erh tea for centuries for its wellbeing and stimulant properties. p0025 Pu-erh tea evolved from its use primarily as a medicine harvested in forests, to a beverage
... It is believed that the longer preservation period is better for the quality of pu-erh tea. These features of the tea differ greatly from those of green tea, which is unfermented and is preferably taken as fresh as possible, Some reports, including our previous study, showed that pu-erh tea has an hypolipidemic and antiobesity effects in rat [3][4][5] and human [6]. These ef-fects are the same as those caused by green tea and green tea catechins [7][8][9][10], though the total content of monomeric catechins in pu-erh tea leaves is low (ca. ...
Article
Full-text available
Pu-erh tea is one of post fermented tea manufactured through oxidative maturing by microorganisms. We investigated the preventive effects of pu-erh tea extract on oxazolone-induced type IV allergy in male (ICR) mice. Oral administration of 50 mg/kg water extract of pu-erh tea leaves resulted in significant preventive effects against mouse type IV allergy. The hydrophilic Theabrownin-like fraction (TBW-ND), with a high molecular weight of approximately 12,000 or higher, was prepared from pu-erh tea leaves by a solvent-extraction method, followed by Diaion HP-20 column chro-matography and dialysis. Oral and percutaneous administrations of TBW-ND at doses of 18.7 mg/kg and 0.037 mg/ear also resulted in significant preventive effects, which included preventing increases in levels of the proinflam-matory cytokine interleukin-12. The anti-allergic ingredients in TBW-ND were predicted to be highly complex compounds containing of polyphenols, polysaccharides and/or proteins. The results suggest pu-erh tea leaves could be a beneficial food for protecting against delayed-type allergy.
... Pu-erh or pu'er is a fermented dark tea, black to brown in colour, with a moderate taste, and is produced only in Yunnan province, China. The role of pu-erh tea as an anti-oxidative agent for reducing cholesterol levels and aiding digestion is well acknowledged (Hou et al., 2009;Cao et al., 2011). There are two main categories of pu-erh tea, namely raw and ripened (Tian et al., 2013). ...
Article
Chinese traditional fermented foods have a very long history, dating back thousands of years and have become an indispensable part of Chinese dietary culture. A plethora of research has been conducted to unravel the composition and dynamics of microbial consortia associated with Chinese traditional fermented foods using culture dependent as well as culture independent methods, like different high throughput sequencing (HTS) techniques. These HTS techniques enable us to understand the relationship between a food product and its microbes to a greater extent than ever before. Considering the importance of Chinese traditional fermented products, the objective of this paper is to review the diversity and dynamics of microbiota in Chinese traditional fermented foods revealed by HTS approaches
... CDTs are mainly produced in southwestern China in Yunnan, Hunan, Hubei, Sichuan, and Guangxi provinces. The CDT variety known as pu-erh tea has been widely reported to promote health (1,2) and to contain many beneficial chemical constituents (3). ...
Article
Chinese dark tea (CDT) was investigated for chemical characteristics using liquid chromatography coupled with tandem mass spectrometry (LC-MS) metabolomics analysis. The LC-MSn method was used for detection of secondary metabolites in 10 CDT varieties. Pattern recognition methods, including principal component analysis (PCA) and orthogonal projection on latent structure-discriminant analysis (OPLS-DA), revealed clear differences and classified the CDT varieties into 2 categories. One category is fermented with Aspergillus niger while the other (fu teas) is fermented with Eurotium cristatum. Chemical analyses identified 25 marker compounds that contribute to the classification of the 2 CDT types. Flavonoid triglycosides and catechin derivatives were the distinctive compounds of fu teas, based on MS/MS fragmentation analysis. Although both fu teas and dark teas are commonly called CDTs, differences between these two CDT types are significant in the chemical classification.
... Numerous studies have been conducted on these effects, including in vivo, in vitro and clinical studies. In general, studies on humans (Fujita & Yamagami, 2007Li et al., 2009), animals (Cao et al., 2011;Ding et al., 2015;Gong, Peng, Chen, Gao, & Zhou, 2010;Hou et al., 2009;Hwang, Lin, Chen, Liuchuang, & Shiao, 2003), and cell lines (Lu & Hwang, 2008;Way et al., 2009) have all confirmed that Pu-erh tea has lipid-lowering effects (Zou, Ding, & Liang, 2012). ...
Article
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In this study, successive extractions of the Pu-erh tea were performed utilising water, chloroform, ethyl acetate, and n-butanol. The different extracts were investigated for regulation of transcription factors involved in lipid metabolism including Farnesoid X Receptor (FXR), Liver X-activated Receptor (LXR), and the Peroxisome Proliferator-Activated Receptor (PPARγ and PPARδ) using reporter gene assays. The data indicated that the ethyl acetate extract had the strongest activation potential for FXR and PPARδ, and Fraction 6 from the ethyl acetate extract obtained by column chromatography had the highest hypolipidaemic potential. Further chromatographic separation of Fraction 6 led to the isolation of 7 flavonoids, and their contents varied between 7.6 and 51.8mg/g. Additionally, sixty-four chemical constituents were identified from Fraction 6 by UPLC-MS/MS and their relative amounts were determined by the ion intensity. These results showed that the flavonoids were the major bioactive compounds in Pu-erh tea responsible for its hypolipidaemic effects.
... Tea is one of the most popular beverages worldwide and can be categorized into three types: nonfermented green, partially fermented oolong, and fully fermented black and Puerh tea [15]. Several biological functions of Pu-erh tea have been reported, such as antiobesity [16], antihyperlipidemia [17], anti-liver fat accumulation [18], and promoting skeletal muscle glucose transport [19]. Also, epigallocatechin gallate, a compound from tea, has been shown to reduce intestinal lipid absorption [20] and lower blood lipids [21]. ...
Article
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This study was to explore the protective effects of Deepure tea against insulin resistance and hepatic steatosis and elucidate the potential underlying molecular mechanisms. C57BL/6 mice were fed with a high fat diet (HFD) for 8 weeks to induce the metabolic syndrome. In the Deepure tea group, HFD mice were administrated with Deepure tea at 160 mg/kg/day by gavage for 14 days. The mice in HFD group received water in the same way over the same period. The age-matched C57BL/6 mice fed with standard chow were used as normal control. Compared to the mice in HFD group, mice that received Deepure tea showed significantly reduced plasma insulin and improved insulin sensitivity. Deepure tea increased the expression of insulin receptor substrate 2 (IRS-2), which plays an important role in hepatic insulin signaling pathway. Deepure tea also led to a decrease in hepatic fatty acid synthesis and lipid accumulation, which were mediated by the downregulation of sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthesis (FAS), and acetyl-CoA carboxylase (ACC) proteins that are involved in liver lipogenesis. These results suggest that Deepure tea may be effective for protecting against insulin resistance and hepatic steatosis via modulating IRS-2 and downstream signaling SREBP-1c, FAS, and ACC.
... CHAPTER 5 Pu-erh Tea: Botany, Production, and Chemistry hypo-cholesterolemic effects, anti-obesity, anti-viral, anti-mutagenic, anti-microbial, anticarcinogenic, anti-diabetic, and neuro-protective effects (Jie et al., 2006;Duh et al., 2004;Qian et al., 2005;Sano et al., 1986;Kuo et al., 2005;Wang et al., 2008;Wang et al., 2010;Syu et al., 2008;Way et al., 2009;Cao et al., 2010;Chen et al., 2009;Gong et al., 2010;Zhang 2010). Pu-erh teas have also been found to prevent tooth decay and ulcers, control halitosis, cure stomach disorders, improve bacterial flora in the intestine, increase bone density, and protect against UV rays . ...
Chapter
Pu-erh (pu’er) tea refers to processed leaves and buds of the broad-leaf variety of the tea plant ( Camellia sinensis var. assamica (L.) O. Kuntze; Theaceae) primarily sourced from China’s Yunnan province, as well as from neighboring areas of southwestern China, Laos, Vietnam, Myanmar, Cambodia, and northeastern India. This region is the center of origin of the tea plant. The diverse habitats from where pu-erh tea is sourced result in a botanical product that is highly heterogeneous in terms of sensory profiles and morphological, phytochemical, and genetic variation. Pu-erh may be processed as a loose or pressed green tea or a post-fermented black. Unlike other green teas, the heat-processing step is less complete for green pu-erh, and consequently it has a distinct oxidation profile with age. Fresh green pu-erh has similar health claims to other green teas while aged green pu-erh and post-fermented black pu-erh have additional health claims unique to fermented foods and beverages. Black post-fermented pu-erh is distinct from other black teas in that it undergoes fermentation by microbial enzymes. This results in the formation of new chemical constituents and fermentation-derived compounds with pro-biotic health claims.
... Raw tea refers to that in the process of gradual darkening through exposure to daylight, whereas ripened tea refers to that in the process of piling before undergoing proper postfermentation (Wang et al., 2011;Lv et al., 2013). With its cultural connotations, high quality, and unique taste, Pu-erh tea is locally revered as historical tea and has attracted an increasing number of consumers and tea dealers (Cao et al., 2011;Pang et al., 2012). Time Magazine once called it 'China's next hot commodity'. ...
Article
To develop an objective, effective, flexible and cost-saving method to assess Pu-erh tea quality, Pu-erh tea samples of different grade levels and various ages were analysed using sensory evaluation and various instrumental techniques, including chemical analysis and electronic tongue (ET). Results showed that taste profile analysis as a sensory evaluation method can meticulously describe and distinguish different Pu-erh tea samples. Chemical analysis combined with hierarchical cluster analysis can cluster Pu-erh ripened and raw tea both in compressed and scattered forms. However, no obvious variation tendency was observed in the chemical composition parameters of Pu-erh tea of different grade levels or various ages. ET combined with principal components analysis (PCA) is effective in classifying Pu-erh tea samples of different grade levels and various ages. ET followed by linear discriminant analysis (LDA) performs well in identifying Pu-erh tea samples of various ages by establishing a discriminant model.
... 17 In the past few decades, the unique effects of Puer tea have been extensively studied, and results indicate that Puer tea possesses a broad range of health-promoting effects, including hypoglycemic effects 18,19 and improvement of type II diabetes, as well as inhibition of the progression of diabetic complications. 20 Of pertinence to the study reported here, studies in rodents have shown that consumption of Puer tea can decrease weight gain 21,22 and improve hyperlipidemia conditions. 23- 25 The beneficial properties of Puer tea may in part be attributable to the bioactive components theabrownin, 26 theaflavins, 12 and complex polysaccharides. ...
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Objective The goal for this study was to evaluate the effects of daily consumption of Puer tea extract (PTE) on body weight, body-fat composition, and lipid profile in a non-Asian population in the absence of dietary restrictions. Materials and methods A randomized, double-blind, placebo-controlled study design was used. A total of 59 overweight or mildly obese subjects were enrolled upon screening to confirm fasting cholesterol level at or above 220 mg/dL (5.7 mmol/dL). After giving informed consent, subjects were randomized to consume PTE (3 g/day) or placebo for 20 weeks. At baseline and at 4-week intervals, blood lipids, C-reactive protein, and fasting blood glucose were evaluated. A dual-energy X-ray absorptiometry scan was performed at baseline and at study exit to evaluate changes to body composition. Appetite and physical and mental energy were scored at each visit using visual analog scales (0–100). Results Consumption of PTE was associated with statistically significant weight loss when compared to placebo (P<0.05). Fat loss was seen for arms, legs, and the gynoid region (hip/belly), as well as for total fat mass. The fat reduction reached significance on within-group analysis, but did not reach between-group significance. Consumption of PTE was associated with improvements to lipid profile, including a mild reduction in cholesterol and the cholesterol:high-density lipoprotein ratio after only 4 weeks, as well as a reduction in triglycerides and very small-density lipoproteins, where average blood levels reached normal range at 8 weeks and remained within normal range for the duration of the study (P<0.08). No significant changes between the PTE group and the placebo group were seen for fasting glucose or C-reactive protein. A transient reduction in appetite was seen in the PTE group when compared to placebo (P<0.1). Conclusion The results from this clinical study showed that the daily consumption of PTE was associated with significant weight loss, reduced body mass index, and an improved lipid profile.
... Pu-erh tea administration significantly lowered plasma TC and TG concentrations and the LDL-c level but did not affect HDL-c levels. Moreover, pu-erh tea significantly increased LPL, HL, and HSL activities in epididymal fat tissue in rats with HFD-induced obesity (Cao et al., 2011). Resveratrol acted mainly on ATGL to regulate lipolytic activity in humans and murine adipocytes (Lasa et al., 2012) and increased Sirt1, Foxo1, and adiponectin mRNA expressions (Costa Cdos et al., 2011;Timmers et al., 2011;Lasa et al., 2012). ...
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With the improvement of living conditions and the popularity of unhealthy eating and living habits, obesity is becoming a global epidemic. Obesity is now recognized as a disease that not only increases the risk of metabolic diseases such as type 2 diabetes (T2D), non-alcoholic fatty liver disease (NAFLD), cardiovascular disease (CVD), and cancer but also negatively affects longevity and the quality of life. The traditional Chinese medicines (TCMs) are highly enriched in bioactive compounds and have been used for the treatment of obesity and obesity-related metabolic diseases over a long period of time. In this review, we selected the most commonly used anti-obesity or anti-hyperlipidemia TCMs and, where known, their major bioactive compounds. We then summarized their multi-target molecular mechanisms, specifically focusing on lipid metabolism, including the modulation of lipid absorption, reduction of lipid synthesis, and increase of lipid decomposition and lipid transportation, as well as the regulation of appetite. This review produces a current and comprehensive understanding of integrative and systematic mechanisms for the use of TCMs for anti-obesity. We also advocate taking advantage of TCMs as another therapy for interventions on obesity-related diseases, as well as stressing the fact that more is needed to be done, scientifically, to determine the active compounds and modes of action of the TCMs.
... Chinese dark teas have been consumed by many people of Southeast Asia, Europe and America. Most of the preparation of CDTs in animal experiments and clinical trials were crude extracts, the quality of which was still represented by total tea polyphenols (Cao et al., 2011;Duh, Yen, Yen, Wang, & Chang, 2004). From this study, it can be accepted that microbial metabolites of tea polyphenols are stronger antioxidant agents than common tea polyphenols. ...
Article
Phytochemical investigation of the aqueous extract of pu-erh tea afforded eight novel 8-C N-ethyl-2-pyrrolidinone substituted flavan-3-ols (puerins I-VIII) by (1)H, (13)C, two-dimensional nuclear magnetic resonance (NMR) and high-performance liquid chromatography with diode array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS) analysis. Comparative chemical analysis of green tea, black tea and Chinese dark teas confirmed that these compounds were the marker compounds of Chinese dark teas. Furthermore, fungal fermentation was indispensable for the biosynthesis of these novel compounds. Through single fungal fermentation, it was proved that catechins and theanine were the precursors of puerins I-VIII. HPLC-DAD-ESI/MS analysis elucidated the biosynthetic pathway for puerins I-VIII. Puerins I-IV have potential protective effects for the human micro-vascular endothelial cells (HMEC) injury induced by hydrogen dioxide compared to other tea polyphenols. 8-C N-ethyl-2-pyrrolidinone substituted flavan-3-ols could be used in the quality control and authentication of Chinese dark teas.
... A review of the epidemiological literature some 8 years ago did identify tea (-)-epigallocatechin gallate as having antiobesity and antidiabetic activity but human health benefit was not generally conclusive [125]. One report, vide supra, using Pu'er tea as the intervention gave statistically significant reductions in many key variables such as the body mass index, waist-hip ratio, fasting serum glucose and lipoproteins [113], with similar indication from another group [114] and arrested visceral fat gain and lipidaemia in rats fed a high fat diet [126]. ...
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Directed against the global pandemic of inflammatory diseases, this group has outlined perspectives on possible health benefits of tea drinking or ingestion of tea extracts. Drawn from the scientific literature, this group has focussed mainly on Green Tea, Black (red) Tea, and Pu'er Tea but not herbal 'tea'. This report has considered historical aspects of tea consumption, the chemical composition, principally polyphenols in their multifarious form e.g. catechins, dimers, thearubigens, etc. The focus has been on oxidative stress and related mechanisms and their impact on the incidence of obesity, metabolic syndrome, diabetes, and cardiovascular disease. The main outcome has been the amalgamation of evidence on mainly rodents and humans which generally indicate beneficial effects but as yet, despite the enormous work, potential functional foods based on tea products require further research.
... Fermented black tea is known to modulate blood lipids and provide anti-inflammatory effects and protection against antioxidative stress [7][8][9][10]. Pu-erh tea, a black tea produced in Yunnan, China, is a postfermented (secondary fermentation) tea made from the large sundried, raw, green Yunnan leaves. ...
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We explored whether pu-erh tea consumption ameliorates atherosclerosis and the possible mechanism for its effects in apolipoprotein E-deficient (ApoE −/− ) mice. Our data showed that pu-erh tea consumption markedly reduced early fatty streak formation and the advanced fibrofatty plaque sizes. Additionally, the mean proportion of inflammatory macrophages in the plaque decreased, and the number of apoptotic macrophages increased significantly. NF- κ B activity in peritoneal macrophages decreased by 75.6% compared to the controls, similar with the levels of IL-6, IL-12, and TNF- α expression. The tea extract increased the apoptosis of RAW264.7 cells by decreasing NF- κ B activation and reducing the inflammatory cytokine expression. In conclusion, pu-erh tea ameliorates atherosclerosis progress by alleviating the chronic inflammatory state by reducing NF- κ B activation and promoting macrophage apoptosis in atherosclerotic plaques.
... Previous reports show that green tea can suppress adipogenesis and lipid synthesis by increasing energy expenditure via thermogenesis, fat oxidation and fecal lipid excretion [152]. Consistently, evidence on this review showed that black and Pu-erh teas have great potential in ameliorating obesity associated complications by mainly reducing visceral fat deposition and lowering hepatic triglyceride levels [15,117,121,122,127,145]. ...
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Metabolic complications in an obese state can be aggravated by an abnormal inflammatory response and enhanced production of reactive oxygen species. Pro-inflammatory response is known to be associated with the formation of toxic reactive oxygen species and subsequent generation of oxidative stress. Indeed, adipocytes from obese individuals display an altered adipokine profile, with upregulated expression and secretion of pro-inflammatory cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin (IL-6). Interestingly, natural compounds, including phenolic enriched foods are increasingly explored for their ameliorative effects against various metabolic diseases. Of interest is gallic acid, a trihydroxybenzoic acid that has progressively demonstrated robust anti-obesity capabilities in various experimental models. In addition to reducing excessive lipid storage in obese subjects, gallic acid has been shown to specifically target the adipose tissue to suppress lipogenesis, improve insulin signaling, and concomitantly combat raised pro-inflammatory response and oxidative stress. This review will revise mechanisms involved in the pathophysiological effects of inflammation and oxidative stress in an obese state. To better inform on its therapeutic potential and improvement of human health, available evidence reporting on the anti-obesity properties of gallic acid and its derivatives will be discussed, with emphases on its modulatory effect on molecular mechanisms involved in insulin signaling, inflammation and oxidative stress.
... The hypotriglyceridemic and anti-obesity effects of teas, including PET, and their derivatives have been well documented in clinical trials and in studies using murine models (reviewed by Lee and Jia 2015;Lee and Foo 2013). Most have focused on their effects on host energy expenditure and lipid metabolism (e.g., Seo et al. 2017;Kemperman et al. 2013;Cao et al. 2011), but only a few have reported their impact on the biodiversity and activity of the host intestinal microbiota. Almost all the microbial studies (reviewed by Valdés et al. 2015) used 16S rRNA-based techniques alone to elucidate the microbiome community structure; with these techniques, conflicting compositional data arising from the biases of PCR-based techniques (Pinto and Raskin 2012) cannot be avoided. ...
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Pu-erh tea is attracting increased attention worldwide because of its unique flavor and health effects, but its impact on the composition and function of the gut microbiota remains unclear. The aim of this study was to investigate the effects of aqueous extracts of fermented (ripe) and non-fermented (raw) Pu-erh teas on the composition and function of the intestinal microbiota of rats with diet-induced obesity. We conducted a comparative metagenomic and meta-proteomic investigation of the microbial communities in cecal samples taken from obese rats treated with or without extracts of raw or ripe Pu-erh teas. By analyzing the composition and diversity of 16S rRNA amplicons and expression profiles of 814 distinct proteins, we found that despite differences in the chemical compositions of raw and ripe Pu-erh teas, administration of either tea at two doses (0.15- and 0.40-g/kg body weight) significantly (P < 0.05) increased microbial diversity and changed the composition of cecal microbiota by increasing the relative abundances of Firmicutes and decreasing those of Bacteroidetes. Community metabolic processes, including sucrose metabolism, glycolysis, and syntheses of proteins, rRNAs, and antibiotics were significantly (P < 0.05) promoted or had a tendency (0.10 < P < 0.05) to be promoted due to the enrichment of relevant enzymes. Furthermore, evidence at population, molecular, and metabolic levels indicated that polyphenols of raw Pu-erh tea and their metabolites potentially promote Akkermansia muciniphila growth by stimulating a type II and III secretion system protein, the elongation factor Tu, and a glyceraldehyde-3-phosphate dehydrogenase. This study provides new evidence for the prebiotic effects of Pu-erh tea.
... Pu-erh tea is characterized by its distinctive aroma, dark red color, and mild taste [1]. Pu-erh tea has been shown to regulate blood lipid concentration, blood glucose, fat levels in the liver, and weight loss [1][2][3][4][5][6]. These bioactive properties of Pu-erh tea are attributed mainly to theabrownin, a complex water soluble polyphenolic substance that is insoluble in nonpolar organic solvents. ...
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Purpose Theabrownin (TB)-containing Pu-erh tea has been shown to be hypolipidemic in rats fed a high-fat diet. Physical exercise such as swinging is also known to reduce obesity. We hypothesized that TB in combination with swinging can synergistically ameliorate obesity and insulin resistance in rats with metabolic syndrome. Methods TB, rosiglitazone, or lovastatin (controls) was administered by gavage to rats fed a diet high in fat, sugar, and salt. A subgroup of the rats was subjected to a 30-min daily swinging exercise regimen, whereas the other rats did not exercise. Results Theabrownin in combination with swinging was found to significantly improve serum lipid status and prevent development of obesity and insulin resistance in rats. Liver transcriptomics data suggested that theabrownin activated circadian rhythm, protein kinase A, the adenosine monophosphate-activated protein kinase, and insulin signaling pathways by enhancing cyclic adenosine monophosphate levels and, hence, accelerating nutrient metabolism and the consumption of sugar and fat. The serum dopamine levels in rats increased significantly after exercise. In parallel work, intraperitoneal dopamine injections were shown to significantly reduce weight gain and prevent the elevation in triglyceride levels that would otherwise be induced by the high fat-sugar–salt diet. Theabrownin prevented obesity and insulin resistance mainly by affecting the circadian rhythm, while swinging exercise stimulated the overproduction of dopamine to accelerate metabolism of glucose and lipid. Conclusions Theabrownin and exercise synergistically ameliorated metabolic syndrome in rats and effectively prevented obesity.
... The primary cause of hepatic insulin resistance is the adipose tissue dysfunction characterized by an increased hepatic glucose production, as well as peripheral insulin resistance in skeletal muscle (Guilherme et al., 2008). Studies in animal models show that a high-fat diet consumption establishes an increase in visceral adiposity and is etiologically associated with dyslipidemia, hyperinsulinemia and hepatic dysfunction, a clinical condition often associated with human obesity (Cao et al., 2011). ...
Article
Introduction: Gallic acid (GA) is a natural endogenous polyphenol found in a variety of fruits, vegetables and wines, with beneficial effects on the energetic homeostasis. Aim: The present study aimed to investigate oral gallic acid effects on liver steatosis and hepatic lipogenesis markers in obese mice evaluating new possible molecular related mechanisms. Methods: Twenty-four Swiss male mice were divided into four groups and fed for 60 days with standard diet (ST), standard diet plus gallic acid (ST + GA), high-fat diet (HFD), and high-fat diet plus gallic acid (HFD + GA). We evaluated the relationship between body weight, food intake and serum levels of total cholesterol, triglycerides, insulin, aspartate and alanine transaminases. Liver histology was analyzed by hematoxylin and eosin staining. These results were accompanied by bioinformatics analyses. The acetyl-CoA carboxylase (ACC), sterol regulatory element binding protein-1 (SREBP-1) and fatty acid synthase (FAS) expression was assessed by quantitative real-time reverse transcriptase PCR (qRT-PCR). Results: The main findings of the present study showed that GA reduced liver steatosis, body weight and plasma insulin levels. Analyzes of hepatic steatosis related genes expression showed that ACC and FAS mRNA were significantly suppressed in liver of HFD + GA mice. These data was corroborated by bioinformatics analysis. Conclusion: These data suggest an important clinical application of GA in the prevention of liver diseases.
... Numerous health benefits of tea leaves beverage consumption are the results of antioxidants presence, e.g. catechins: epigallocatechin-3-gallate (EGCG), epigallocatechin (EGC), epicatechin (EC), and catechin (C), as well as L-theanine or an alkaloid -caffeine [6,7,18,20,32,41]. The healthy effect of tea on the human body is mainly attributed to the increase in the blood antioxidant capacity by polyphenols, which protect cells and tissues from the damaging effects of oxidation, exhibiting anticancer, antimicrobial, and antidiabetic activity, and having many more health benefits [12, 16,19,23,24,28,35,42]. ...
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http://www.ejpau.media.pl/volume20/issue2/art-02.html In recent years an increased interest in healthy lifestyle caused that other types of tea, e.g. Pu Erh, are also increasingly selected by the consumers. Currently, Pu Erh tea is considered to promote weight loss, as well as support the treatment of numerous diseases, by neutralizing free radicals activity in the human body. Present research aimed at the evaluation of antiradical capacity of Pu Erh tea leaves available on the Polish market. The research was conducted on seven Pu Erh teas produced according to the accelerated ripening method (wo dui), supplied by Polish dealers. Pu Erh tea was subjected to traditional brewing methods, followed by DPPH and ABTS radical reducing activity assays. Tea leaves and its brews were also characterized according to the commodity value. The antiradical capacity of Pu Erh tea leaves showed that examined teas exhibited antiradical properties, however in a varied degree, not conditioned by the type of tea and brewing time. The quality of tea had no significant effect on the ability to reduce the DPPH and ABTS radicals, whereas it affected the extraction process efficiency. Pu Erh tea may be a dietary source of antioxidants, helping with the treatment of diseases caused by free radicals activity, such as diabetes or coronary heart disease.
... However, the level of LDL-C was elevated in the groups administrated with Fenghuang Narcissus (T8), Qing Brick (T9), and Mengding Huangya (T12) teas when comparing with the HFD model group.Previous researches reported that obesity and NAFLD could affect lipid metabolism as well as contribute to hypercholesterolemia and hypertriglyceridemia(Gaggini et al., 2013;Shin & Jung, 2017;Vekic et al., 2019). Several studies suggested that the supplementation of tea could lead to the decrease in the level of serum TG(Cao et al., 2011;Chen et al., 2018). However, the effects of tea on lowering serum TC and LDL-C were controversial based on the results from different studies, which might be due to the difference in duration and dose of tea treatment. ...
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Nonalcoholic fatty liver disease (NAFLD) is considered as a severe threat to human health. It has been reported that tea has abundant bioactive compounds and beneficial effects. In our study, the effects of 12 tea extracts on NAFLD were assessed and compared at the dose of 200 mg/kg body weight in mice fed with a high‐fat diet (HFD) for 15 weeks. Enshi Yulu Tea, Fenghuang Narcissus Tea, and Yihong Tea showed strong effects in suppressing the accumulation of epididymal and perirenal adipose tissue as well as the increases of body weight and liver weight. The histopathological analysis revealed that hepatic steatosis and adipocyte hypertrophy induced by a HFD could be ameliorated by tea supplementation. In addition, Enshi Yulu Tea and Qing Brick Tea exerted more remarkable functions on decreasing the level of serum triglyceride and preventing hepatic fat accumulation, respectively. Furthermore, Fenghuang Narcissus Tea, Enshi Yulu Tea, and Qing Brick Tea could reverse the abnormal change in the levels of glutathione and superoxide dismutase. Moreover, 13 phytoconstituents were detected and quantified in these teas with high‐performance liquid chromatography (HPLC) method. The correlation analysis demonstrated that gallic acid might decrease MDA level, and the reduction of liver weight might be attributed to ellagic acid. However, it should be paid attention to some teas that showed hepatotoxicity with elevated levels of aspartate transaminase and alanine aminotransferase. Several teas showed strong effects in the prevention of NAFLD, which could be developed into functional foods against NAFLD.
... A review of the epidemiological literature some 8 years ago did identify tea (-)-epigallocatechin gallate as having antiobesity and antidiabetic activity but human health benefit was not generally conclusive [125]. One report, vide supra, using Pu'er tea as the intervention gave statistically significant reductions in many key variables such as the body mass index, waist-hip ratio, fasting serum glucose and lipoproteins [113], with similar indication from another group [114] and arrested visceral fat gain and lipidaemia in rats fed a high fat diet [126]. ...
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Directed against the global pandemic of inflammatory diseases, this group has outlined perspectives on possible health benefits of tea drinking or ingestion of tea extracts. Drawn from the scientific literature, this group has focussed mainly on Green Tea, Black (red) Tea, and Pu’er Tea but not herbal ‘tea.’ This report has considered historical aspects of tea consumption, the chemical composition, principally polyphenols in their multifarious form e.g., catechins, dimers, thearubigens, etc. The focus has been on oxidative stress and related mechanisms and their impact on the incidence of obesity, metabolic syndrome, diabetes, and cardiovascular disease. The main outcome has been the amalgamation of evidence on mainly rodents and humans which generally indicate beneficial effects but as yet, despite the enormous work, potential functional foods based on tea products require further research.
... On the other hand, numerous animal studies have demonstrated that green tea and its processed products (e.g. oolong tea and black tea) exhibit lipid-lowering effects (16)(17)(18)(19)(20)(21)(22)(23)(24)(25) . The hypotriglyceridaemic effects of green tea and its derivatives have also been well documented in clinical trials and have recently been intensively reviewed (26) . ...
Article
Hyperlipidaemia is a major cause of atherosclerosis and related CVD and can be prevented with natural substances. Previously, we reported that a novel Bacillus-fermented green tea (FGT) exerts anti-obesity and hypolipidaemic effects. This study further investigated the hypotriglyceridaemic and anti-obesogenic effects of FGT and its underlying mechanisms. FGT effectively inhibited pancreatic lipase activity in vitro (IC50, 0·48 mg/ml) and ameliorated postprandial lipaemia in rats (26 % reduction with 500 mg/kg FGT). In hypertriglyceridaemic hamsters, FGT administration significantly reduced plasma TAG levels. In mice, FGT administration (500 mg/kg) for 2 weeks augmented energy expenditure by 22 % through the induction of plasma serotonin, a neurotransmitter that modulates energy expenditure and mRNA expressions of lipid metabolism genes in peripheral tissues. Analysis of the gut microbiota showed that FGT reduced the proportion of the phylum Firmicutes in hamsters, which could further contribute to its anti-obesity effects. Collectively, these data demonstrate that FGT decreases plasma TAG levels via multiple mechanisms including inhibition of pancreatic lipase, augmentation of energy expenditure, induction of serotonin secretion and alteration of gut microbiota. These results suggest that FGT may be a useful natural agent for preventing hypertriglyceridaemia and obesity.
... Increasing evidence showed that Pu-erh tea exhibited a wide range of health benefits including anti-diabetics, -oxidation, -obesity, -mutagenic, and -atherosclerosis. But few reported on the mechanism of inducing oxidative stress of the liver [22][23][24][25][26]. Oxidative stress status occurs when ROS accumulate. ...
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Reducing oxidative stress and hepatoprotective effect of Pu-erh tea water extracts on rats fed with high-fat diet were researched for explaining health care of Pu-erh tea. Fifty SD rats were divided into five groups. The body weight was measured once a day. The malondialdehyde (MDA) and glucose (Glu) levels and the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide synthase (NOS), and pyruvate kinase (PK) in serum were determined. Furthermore, the hepatic glycogen level (HGL) and the activities of hepatic total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were also measured after continuous administration for 12 weeks. The result demonstrated that Pu-erh extract caused the decreases in body weight, fat index, MDA and NOS levels, and the increases in hepatic T-SOD, CAT and GSH-Px activities, indicating that the extract may be due to inhibiting the increases of body weight and fat index, reducing oxidant stress state and inhibiting lipid peroxidation, thus decreasing the activities of ALT and AST, and protecting the liver in rat. Meanwhile, the extracts could increase the production of hepatic glycogen and the activity of PK, and reduce glucose level, protecting the liver from the diseases associated with type II diabetes.
Article
Puerh tea has been proposed to promote weight loss and favorably modify glucose, insulin and blood lipids. This study tested the effect of daily Puerh tea consumption for 3 months on weight and body mass index (BMI), and select metabolic parameters. The effect of daily Puerh tea intake on weight, BMI and changes in glucose, HbA1c and lipids was evaluated in patients with metabolic syndrome. The patients (N = 70) were randomized into two groups: those taking Puerh tea extract capsule (333 mg Puerh tea extract) three times a day and those taking a placebo tea for 3 months. There was a decrease in body weight of 1.3 kg in the Puerh tea group (p = 0.077) versus 0.23 kg in the placebo arm (p = 0.186). There was also a slight decrease in BMI 0.47 kg/m(2) in the Puerh tea group (p = 0.076) versus 0.09 kg/m(2) in the placebo arm (p = 0.185), suggesting a trend of weight change, but without statistical significance. Subgroup analysis of the male patients demonstrated statistically significant improvements in body weight reduction (p = 0.004) and BMI (p = 0.004). However, the change in other metabolic parameters (cholesterol or triglyceride) or HbA1c was not statistically significant. Intake of Puerh tea for 3 months was associated with a slight reduction in body weight and BMI, especially in the male patients. Therefore, daily Puerh tea consumption may be an alternative choice to modify body weight. Copyright © 2014 John Wiley & Sons, Ltd.
Article
Ethnopharmacological relevance Kucha tea plant (Camellia assamica var. kucha Chang et Wang) is regarded as a mutant variety of wild Pu’er tea plant found in few mountain areas of Yunnan, China. Its fresh young leaves and shoots are picked by the indigenous aborigines in these local areas to prepare an herbal tea for the treatment of common cold empirically. Materials and methods Two extra compounds of relative abundance were detected in Kucha tea in comparison with Pu’er tea, and their chemical structures were identified as chlorogenic acid and theacrine. These two compounds as well as two major compounds, strictinin and caffeine, in Kucha tea were evaluated for their cytotoxicity and inhibitory effects on human influenza virus A/Puerto Rico/8/34 by analyzing viral protein expression and progeny production. Results No or low cytotoxicity was detected for the four Kucha compounds when their concentrations were below 100 μM. Expression of viral NS1 protein was significantly inhibited by chlorogenic acid, theacrine or strictinin, but not caffeine at a concentration of 100 μM. The relative inhibitory potency was detected as chlorogenic acid < theacrine < strictinin, and both theacrine and strictinin displayed significant inhibition at a concentration of 50 μM. According to a plaque assay, viral progeny production was significantly reduced by theacrine or strictinin, but not by chlorogenic acid or caffeine under the same concentration of 100 μM. Conclusion It is suggested that theacrine and strictinin are two major ingredients responsible for the anti-influenza activity of Yunnan Kucha tea traditionally used for the treatment of common cold.
Article
A mechanochemical pretreatment was used prior to aqueous extraction of eleutheroside B from Eleutherococcus senticosus. The effects of the mechanochemical assisted extraction parameters hydroxypropyl-β-cyclodextrin (HP-β-CD) content, particle size, and circulating water temperature on the extraction yield of eleutheroside B were investigated. The mechanochemical assisted extraction process was optimized based on an orthogonal experimental design. The optimum process conditions were a HP-β-CD content of 23% (w/w), a particle size of D95 ≤ 44 μm and circulating water temperature of 40 °C. The mechanochemical assisted extraction process produced a higher eleutheroside B extraction yield, using a shorter extraction time and a greatly simplified process compared with traditional heat-reflux extraction, which makes mechanochemical assisted extraction a potential tool for eleutheroside B extraction from Eleutherococcus senticosus. Moreover, this technique used water as the solvent, making mechanochemical assisted extraction a less expensive and eco-friendly technique compared with traditional heat-reflux extraction.
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Pu-erh tea displays cholesterol-lowering properties, but the underlying mechanism has not been elucidated. Theabrownin is one of the most active and abundant pigments in Pu-erh tea. Here, we show that theabrownin alters the gut microbiota in mice and humans, predominantly suppressing microbes associated with bile-salt hydrolase (BSH) activity. Theabrownin increases the levels of ileal conjugated bile acids (BAs) which, in turn, inhibit the intestinal FXR-FGF15 signaling pathway, resulting in increased hepatic production and fecal excretion of BAs, reduced hepatic cholesterol, and decreased lipogenesis. The inhibition of intestinal FXR-FGF15 signaling is accompanied by increased gene expression of enzymes in the alternative BA synthetic pathway, production of hepatic chenodeoxycholic acid, activation of hepatic FXR, and hepatic lipolysis. Our results shed light into the mechanisms behind the cholesterol- and lipid-lowering effects of Pu-erh tea, and suggest that decreased intestinal BSH microbes and/or decreased FXR-FGF15 signaling may be potential anti-hypercholesterolemia and anti-hyperlipidemia therapies.
Article
An UV-quantitative analysis method for the theabrownin (TB) in Pu-erh tea and its derived products was established in the present study. The results showed that the Pu-erh tea shows characteristic absorption at the wavelength of 270 nm, which can be used as wavelength for the content determination of TB. The preparation methods of standard TB and standard curve were also established. The determination results show that the method is simple, the results have certain credibility, and the established method can be used for the determination of TB in Pu-erh tea and its derived products.
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Obesity is a serious health problem in adults and children worldwide. However, the basic strategies for the management of obesity (diet, exercise, drugs and surgery) have limitations and side effects. Therefore, many researchers have sought to identify bioactive components in food. Tea and coffee are the most frequently consumed beverages in the whole world. Their health benefits have been studied for decades, especially those of green tea. The anti-obesity effect of tea and coffee has been studied for at least ten years. The results have shown decreased lipid accumulation in cells via the regulation of the cell cycle during adipogenesis, changes in transcription factors and lipogenesis-related proteins in the adipose tissue of animal models, and decreased body weight and visceral fat in humans. Tea and coffee also influence the gut microbiota in obese animals and humans. Although the anti-obesity mechanism of tea and coffee still needs further clarification, they may have potential as a new strategy to prevent or treat obesity.
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Chinese dark teas (CDTs) are post-fermented tea products, which are mainly produced in Southwestern China. The health benefits and chemistry of CDTs are increasing trends in the research field of teas. Deactivated leaves of Camellia sinensis and Camellia assamica are post-fermented under controlled conditions to make CDTs, the quality of which is dependent on the microorganisms like Aspergillus, Penicillium and Eurotium species in postfermentation process. It has been proved that CDTs have anti-obesity effects with respect to decreasing the total serum cholesterol, triglyceride, low density lipoprotein cholesterol (LDL-C) by inhibiting the lipid absorption and biosynthesis. Furthermore, CDTs possess antimicrobial, antioxidative and antimutagenic activities. Besides the health benefits, the safety of CDTs was assessed by acute and chronic toxicity evaluation. Postfermentation structurally changes the original compounds of raw CDTs, significantly decreases the contents of catechins and forms some novel catechins derivatives. In the present paper, we review the postfermentation characteristics, biological activities, chemical constituents and composition analysis of CDTs.
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Aflatoxins are toxic metabolites produced by fungi. The objective of this study was to develop an HPLC method to detect the presence of aflatoxins in Pu-erh tea. The developed method had recovery rates of 81.02–90.69%. The results revealed that Pu-erh teas from Yunnan, China, contained aflatoxins, especially AFB1 (8.333 μg/kg in raw and 20.149 μg/kg in ripe tea). All tea samples had aflatoxin levels below the national maximum permissible limits; however, the tea samples had higher aflatoxin levels than those allowed in the European Union, the USA, and Japan. The presence of aflatoxins in Pu-erh tea hinders its international marketability.
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Due to misbalanced energy surplus and expenditure, obesity has become a common chronic disorder that is highly associated with many metabolic diseases. Pu-erh tea, a traditional Chinese beverage, has been believed to have numerous health benefits, such as anti-obesity. However, the underlying mechanisms of its anti-obesity effect are yet to be understood. Here, we take the advantages of transcriptional profile by RNA sequencing (RNA-Seq) to view the global gene expression of Pu-erh tea. The model organism Caenorhabditis elegans was treated with different concentrations of Pu-erh tea water extract (PTE, 0 g/mL, 0.025 g/mL, and 0.05 g/mL). Compared with the control, PTE indeed decreases lipid droplets size and fat accumulation. The high-Throughput RNA-Sequence technique detected 18073 and 18105 genes expressed in 0.025 g/mL and 0.05 g/mL PTE treated groups, respectively. Interestingly, the expression of the vitellogenin family (vit-1, vit-2, vit-3, vit-4 and vit-5) was significantly decreased by PTE, which was validated by qPCR analysis. Furthermore, vit-1(ok2616), vit-3(ok2348) and vit-5(ok3239) mutants are insensitive to PTE triggered fat reduction. In conclusion, our transcriptional profile by RNA-Sequence suggests that Pu-erh tea lowers the fat accumulation primarily through repression of the expression of vit(vitellogenin) family, in addition to our previously reported (sterol regulatory element binding protein) SREBP-SCD(stearoyl-CoA desaturase) axis.
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Fuzhuan brick tea has received increasing attention in recent years owing to its benefits for non-alcoholic fatty liver disease (NAFLD) and associated metabolic syndrome. For exploring the ameliorative mechanism, the liver proteomes from three groups of rats fed either a normal control diet (NCD), a high fat diet (HFD), or a HFD supplemented with high-dose FTE (HFD+HFTE) were comprehensively compared by quantitative proteomics using 2DE-LC-MS/MS. This is the first study of the effects of tea aqueous extract on the liver proteome of rats suffering from metabolic syndrome. The results showed that 57 proteins displayed more than 1.5-fold differences in at least one of two comparisons of HFD versus NCD and HFD versus HFD+HFTE due to HFD feeding and FTE treatment, respectively. Of them, over 75% of proteins exhibited a similar tendency of expression in the two comparisons, meaning FTE was able to correct HFD effects on rat livers. By function analyses, an extensive list of proteins were involved in sugar and lipid metabolism. Compared with HFD-fed rats, the reduced lipogenesis and enhanced β-oxidation, tricarboxylic acid cycle and respiratory chain in HFD+HFTE-fed rats, which mainly contributed to ameliorate hepatic fat accumulation and associated NAFLD. Additionally, some putative drug targets were also revealed such as COX2, PGAM1, ACACB, FAS and ECHS1. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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Caffeinated beverages, most commonly tea and coffee, may have important effects on insulin regulation that may give their consumption an important role among nutritional factors in the development of diseases of glucose and insulin metabolism, such as diabetes and atherosclerotic vascular diseases. These beverages include compounds that may have contradictory effects on insulin and glucose: Caffeine impairs insulin sensitivity, but polyphenolic molecules within tea, coffee, and cocoa augment the effects of insulin. In addition, epidemiologic associations exist between greater consumption of such beverages and lower risk of diabetes. The beneficial effects of such beverages might be enhanced by changing the process of their preparation and substitution of other substances commonly added to caffeinated beverages that impair the effect of insulin, such as sugar or milk.
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Polysaccharides-rich dark tea is believed to be beneficial to health in Southeast Asian. However, the hypolipidemic effect of Chinese Liupao tea polysaccharides (CLTPS) has not been investigated. Here, the potential mechanism by which the oral administration of CLTPS affects lipid metabolism was evaluated using high-fat diet-induced hyperlipidemia rats. In rats supplemented with CLTPS, a suppressive effect on body weight was observed after 4 weeks of intervention. CLTPS significantly improved the levels of lipid profiles, the oxidation of lipids and antioxidant enzyme activity in a dose-dependent manner. The cholesterol-lowering action was paralleled by the stimulation of cholesterol converted to bile acids along with a 1.5-fold increase in faecal excretion. Besides, the prolongation of coagulation factors and the reduction in fibrinogen content showed that CLTPS regulated the coagulation initiated through the intrinsic pathway. With current findings, CLTPS may be valuable as a natural hypolipidemic nutraceutical for human consumption.
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It is a challenging task to discriminate raw pu-erh tea, notably aged raw tea, from ripened pu-erh tea, both of which are the two primary types of pu-erh teas, only based on the taster's sensory evaluation. In the current study, a workflow was proposed to differentiate those two clusters of pu-erh teas, as well as to point out and verify the markers responsible for the discrimination. Initially, an electronic nose was utilized for the rapid discrimination. Then, an efficient method based on ultrasound-assisted extraction-dispersive liquid–liquid microextraction-gas chromatography-mass spectrometry (UAE-DLLME-GC-MS) coupled with chemometric methods was developed to disclose the metabolic profiles and pinpoint the markers for discrimination. Afterwards seven methoxyphenolic derivatives were simultaneously determined in both pu-erh teas. The role of volatile components in the classification of pu-erh teas was proved using the electronic nose (E-nose). Diverse parameters were optimized for UAE-DLLME-GC-MS, and a total of 84 volatile constituents were detected and identified. The methoxyphenolic derivatives as well as some alcohol derivatives were screened out as the primary markers by principle component analysis, and significant differences were revealed for the contents of methoxyphenolic compounds in these two types of pu-erh teas. Taken together, methoxyphenolic compounds as well as alcohol derivatives were found and verified as the markers for the differentiation between raw and ripened pu-erh teas, and either an E-nose or UAE-DLLME-GC-MS could be applied as a reliable tool to achieve the discrimination.
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Background: To study the effects of Pu-erh theabrownin (TB) (Mw > 50kDa) on the metabolism of rats serum by nuclear magnetic resonance (NMR)-based metabolomics and identify candidate marker metabolites associated with Pu-erh TB and, thus, provide fundamental information for better understanding the metabolism of Pu-erh tea in animals. Results: The TB infusion induced different changes in endogenous serum metabolites depending on the type of diet. Compared with the control group, the TB infusion group showed significantly reduced serum glycine and choline levels, as well as significantly increased taurine, carnitine, and HDL (all p<0.05). Compared with the high lipid group, the high lipid-TB infusion group exhibited significantly reduced LDL and acetate levels, as well as significantly increased inositol, carnitine, and glycine levels (all p<0.05). Conclusion: Examination of the variations of these differential expressed metabolites and their individual functions revealed that, the TB extract accelerated the lipid catabolism in rats and might affect the glucose metabolism. Of these, the carnitine level significantly increased after intragastric infusion of TB regardless of the type of diet, and carnitine palmitoyltransferases Ι and ΙΙ activities have significantly changed, suggesting carnitine may be a candidate serum marker for tracking the metabolism of TB in rats.
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α-Glucosidase and lipase inhibitors play important roles in the treatment of hyperglycaemia and dyslipidemia. †These authors make equal contributions to this work.To identify novel naturally occurring inhibitors, a bioactivity-guided phytochemical research was performed on the pu-erh tea. One new flavanol, named (–)-epicatechin-3-O-(Z)-coumarate (1), and 16 known analogs (217) were isolated from the aqueous extract of the pu-erh tea. Their structures were determined by spectroscopic and chemical methods. Furthermore, the water extract of pu-erh tea and its fractions exhibited inhibitory activities against α-glucosidases and lipases in vitro; compound 15 showed moderate inhibitory effect against sucrase with an IC50 value of 32.5μmol/L and significant inhibitory effect against maltase with an IC50 value of 1.3μmol/L. Compounds 8, 10, 11 and 15 displayed moderate activity against a lipase with IC50 values of 16.0, 13.6, 19.8, and 13.3μmol/L, respectively.
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There are presently no miracle drugs for non-alcoholic fatty liver disease (NAFLD). This study investigates the synergistic effect of Silibinin combined with Pu-erh tea extract (PTE) against NAFLD and explores the suggested mechanism of action. Ob/ob mice were fed a high fat diet along with the oral administration of Silibinin (86 mg per kg per day), PTE (250 mg per kg per day) or their combination for 6 weeks. Their lean littermates who were fed with standard chow diet were used as the control group. The blood biochemical index and histopathological evaluation were analyzed. The expression of genes involved in the lipogenesis pathway and cholesterol metabolism were evaluated. When compared with that of the NAFLD group, the body weight and blood lipid of the mice from the PTE group or combination group were significantly reduced. To some degree, fat metabolism and the inflammatory response were ameliorated by Silibinin and PTE used alone or in combination. It was notable that the combination group had a stronger efficacy in adjusting fat metabolism and inhibiting oxidative stress than that of Silibinin or PTE used alone. Silibinin and PTE inhibited fat synthesis by regulating the mRNA expression of CRTC2, SREBP-1c, and SCD-1. Moreover, the cholesterol homeostasis was improved in the treatment groups via regulating the mRNA expression of ABCA1 and ApoB100. The improvement of the combination group was superior to each drug used alone. In conclusion, Silibinin in combination with PTE can prevent NAFLD with greater potential than Silibinin or PTE used alone and may be a new therapeutic strategy.
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Fermented puerh tea, undergone a long-time of secondary oxidization and fermentation, has been more and more popular in recent years. In the present paper, the safety evaluation of aqueous extract from fermented puerh tea (EFPT) was investigated, including oral acute toxicity study in rats and mice, mutation tests made up of Ames test, mouse micronucleus test and mouse sperm abnormality test and 30 days feeding study in rats. Meanwhile, the antihyperlipidemia effect of EFPT was investigated as well. It was found that the oral maximum tolerated dose of EFPT was more than 10.0 g/kg body weight both in rats and mice. And it had no mutagenicity judged by negative experimental results of mutation test. No abnormal symptoms and clinical signs or deaths had been found in rats in each group throughout the experiments. In addition, EFPT showed positive effects on hyperlipidemia.
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Although pu-erh tea has been shown to suppress hyperlipidemia, it is unclear how it modulates fatty acid synthase expression in mice fed on a high-fat diet. We investigated the effects of a pu-erh tea extract (PTE) on diet-induced body fat accumulation. C57BL/6J mice were fed a control diet, a high-fat diet (HFD), and HFD supplemented with 0.225% or 0.45% PTE for 70 d. Supplementation with PTE reduced the body weight gain, and the abdominal and liver fat accumulation. A significant difference in the triglyceride level were observed between the HFD control and HFD+0.45% PTE groups. A PTE intake tended to decrease sterol regulatory element-binding protein (SREBP)-1c and fatty acid synthase (FAS) mRNA expression in the liver of the mice. These findings indicate that PTE reduced lipogenesis by down-regulating SREBP-1c and related molecules, leading to the suppression of body fat accumulation.
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A simple and fast HPLC method using a photodiode array detector was developed for simultaneous determination of four major catechins, gallic acid and caffeine. After multiple extractions with aqueous methanol and acidic methanol solutions, tea extract was separated within 20 min using a methanol-acetate-water buffer gradient elution system on a C(18) column. The sample extraction data demonstrated that the single extraction used in the previous studies with aqueous acetonitrile or methanol is not sufficient; the multiple extraction procedure is essential for the quantitative analysis of catechins, phenolic acids and caffeine in teas. Several green, Oolong, black and pu-erh teas were successfully analyzed by this method. The analytical results obtained indicated that green teas contain higher content of catechins [(-)-epigallocatechin gallate, (-)-epigallocatechin, (-)-epicatechin gallate, and (-)-epicatechin] than both Oolong, pu-erh and black teas because fermentation process during the tea manufacturing reduced the levels of catechins significantly. The fermentation process also remarkably elevated the levels of gallic acid in full-fermented pu-erh and black teas. Another interesting finding is the low level of caffeine in Oolong teas, especially in Fujian Oolong tea.
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Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step in adipocyte lipolysis. The activity of HSL is thought to be primarily regulated by reversible phosphorylation. However, the regulation of HSL activity by pre-translational mechanisms has been poorly studied. The present studies were undertaken to explore the relationship between the levels of HSL protein and mRNA expressions and the lipolytic capacity. The study was performed in human abdominal subcutaneous adipocytes with identical sizes but having either a high (HL) or low (LL) lipolytic capacity (n = 16). Basal and maximal lipolysis induced by catecholamines, an adenylyl cyclase activator forskolin, and a cyclic AMP analogue dibutyryl cAMP were 50% lower in LL- in comparison with HL-fat cells (P < 0.05 or better). No differences in drug sensitivity were found. HSL activity and quantity were about 50% lower in LL- compared with HL-fat cells (P < 0.05). Moreover, the mRNA ratio between HSL and gamma-actin was 35% lower in LL- compared with HL-fat cells (P < 0.05). There was a strong linear correlation between the protein and enzymatic HSL measurements (r2 = 0.91). In addition, the maximum lipolytic capacity was significantly correlated with HSL activity (r2 = 0.75) and HSL protein amount (r2 = 0.64). It is concluded that hormone-sensitive lipase (HSL) expression, measured either as total HSL protein by Western blot analysis or as total amount of activatable HSL enzyme, is a major determinant of the maximum lipolytic capacity of human fat cells. In addition, HSL protein expression is at least, in part, determined by HSL mRNA expression.
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Obesity is a highly prevalent condition with significant health implications. This report summarizes recent clinically relevant findings concerning the pathogenesis and treatment of obesity and considers their implications for psychiatric diagnosis and management. The authors conducted selective reviews of the literature from the last 10 years. Topics included the biological and behavioral factors that contribute to the onset and maintenance of obesity, the relationship between obesity and psychiatric illness and treatment, and the questions of whether and how obesity should be treated. Genetic effects, some mediated by eating behavior, contribute importantly to the potential for obesity, the expression of which is promoted by environmental factors that increase the availability of calorically dense foods and discourage activity. There appear to be behaviorally distinct subsets of obese persons who display particular patterns of disordered eating and elevated rates of psychopathology. Treatment with psychotropic medications may contribute to obesity in ways that are only partly understood. Although successful obesity treatment is associated with clear health benefits and available treatments offer benefit to some, relapse remains the rule. Although the presence or development of obesity is a daunting problem, it should not be ignored by mental health professionals. Treatment should address not only obesity per se, but also its effects on self-esteem in a hostile cultural climate. Ongoing developments in basic and clinical research are likely to increase the range, efficacy, and acceptability of treatment options in the years ahead.
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It has been variously hypothesized that the insulin resistance induced in rodents by a high-fat diet is due to increased visceral fat accumulation, to an increase in muscle triglyceride (TG) content, or to an effect of diet composition. In this study we used a number of interventions: fish oil, leptin, caloric restriction, and shorter duration of fat feeding, to try to disassociate an increase in visceral fat from muscle insulin resistance. Substituting fish oil (18% of calories) for corn oil in the high-fat diet partially protected against both the increase in visceral fat and muscle insulin resistance without affecting muscle TG content. Injections of leptin during the last 4 days of a 4-wk period on the high-fat diet partially reversed the increase in visceral fat and the muscle insulin resistance, while completely normalizing muscle TG. Restricting intake of the high-fat diet to 75% of ad libitum completely prevented the increase in visceral fat and muscle insulin resistance. Maximally insulin-stimulated glucose transport was negatively correlated with visceral fat mass (P < 0.001) in both the soleus and epitrochlearis muscles and with muscle TG concentration in the soleus (P < 0.05) but not in the epitrochlearis. Thus we were unable to dissociate the increase in visceral fat from muscle insulin resistance using a variety of approaches. These results support the hypothesis that an increase in visceral fat is associated with development of muscle insulin resistance.
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The maturation of lipoprotein lipase (LPL) into a catalytically active enzyme was believed to occur only after its transport from the endoplasmic reticulum (ER) to the Golgi apparatus. To test this hypothesis, LPL located in these two subcellular compartments was separated and compared. Heparin affinity chromatography resolved low affinity, inactive LPL displaying ER characteristics from a high affinity, active fraction exhibiting both ER and Golgi forms. The latter forms were further separated by beta-ricin chromatography and were found to have comparable activities per unit of LPL mass. Thus, LPL must reach a functional conformation in the ER. Active LPL, regardless of its cellular location, exhibited the expected dimer conformation. However, inactive LPL, found only in the ER, was highly aggregated. Kinetic analysis indicated a concurrent formation of LPL dimer and aggregate and indicated that the two forms have dissimilar fates. Whereas the dimer remained stable even when confined to the ER, the aggregate was degraded. Degradation rates were not affected by proteasomal or lysosomal inhibitors but were markedly reduced by ATP depletion. Lowering the redox potential in the ER by dithiothreitol caused the dimer to associate with calnexin, BiP, and protein-disulfide isomerase to form large, inactive complexes; dithiothreitol removal induced complex dissociation with restoration of the functional LPL dimer. In contrast, the LPL aggregate was only poorly associated with ER chaperones, appearing to be trapped in an irreversible, inactive conformation destined for ER degradation.
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The successful management of obesity requires a long-term approach that is tailored to an individual's lifestyle and needs. Initial treatment should focus on lifestyle modifications-dietary interventions and increased physical activity-with behavioral modification strategies used adjunctively. Several antiobesity drugs are approved by the Food and Drug Administration for use in obese patients, as well as in overweight individuals with at least one obesity-related comorbidity. Most are approved only for short-term weight loss, but sibutramine and orlistat are approved for long-term weight loss and maintenance. In addition to weight reduction, in clinical trials these drugs provided beneficial actions on several cardiovascular risk factors. Several other drugs currently approved for other uses show promise in their ability to cause weight loss. Surgical options should be reserved for severely obese patients with significant medical comorbidities or physical conditions.
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To characterize the meal patterns of free feeding Sprague-Dawley rats that become obese or resist obesity when chronically fed a high-fat diet. Male Sprague-Dawley rats (N = 120) were weaned onto a high-fat diet, and body weight was monitored for 19 weeks. Rats from the upper [diet-induced obese (DIO)] and lower [diet-resistant (DR)] deciles for body-weight gain were selected for study. A cohort of chow-fed (CF) rats weight-matched to the DR group was also studied. Food intake was continuously monitored for 7 consecutive days using a BioDAQ food intake monitoring system. DIO rats were obese, hyperphagic, hyperleptinemic, hyperinsulinemic, hyperglycemic, and hypertriglyceridemic relative to the DR and CF rats. The hyperphagia of DIOs was caused by an increase in meal size, not number. CF rats ate more calories than DR rats; however, this was because of an increase in meal number, not size. When expressed as a function of lean mass, CF and DR rats consumed the same amount of calories. The intermeal intervals of DIO and DR rats were similar; both were longer than CF rats. The nocturnal satiety ratio of DIO rats was significantly lower than DR and CF rats. The proportion of calories eaten during the nocturnal period did not differ among groups. The hyperphagia of a Sprague-Dawley rat model of chronic diet-induced obesity is caused by an increase in meal size, not number. These results are an important step toward understanding the mechanisms underlying differences in feeding behavior of DIO and DR rats.
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Although described initially as an intracellular adipocyte-specific triacylglycerol lipase, it is now clear that HSL (hormone-sensitive lipase) is expressed in multiple tissues and plays a number of roles in lipid metabolism, including that of a neutral cholesteryl ester hydrolase. The major isoform is a single polypeptide with a molecular mass of approx. 84 kDa and which comprises three major domains: a catalytic domain, a regulatory domain encoding several phosphorylation sites and an N-terminal domain involved in protein-protein and protein-lipid interactions. The activity of HSL is regulated acutely by several mechanisms, including reversible phosphorylation by a number of different protein kinases, translocation to different sites within the cell and interaction with a number of proteins, some of which may serve to direct the inhibitory products of HSL away from the protein. It is also apparent from work with HSL null mice that more than one enzyme species may be classified as a hormone-sensitive lipase. The possible presence of HSL in macrophages remains controversial, and the role of the protein in pancreatic beta-cells has yet to be fully elucidated. Altered expression of HSL in different cell types may be associated with a number of pathological states, including obesity, atherosclerosis and Type II diabetes.
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A variety of methods are currently used to analyze HL and LPL activities in mice. In search of a simple methodology, we analyzed mouse preheparin and postheparin plasma LPL and HL activities using specific polyclonal antibodies raised in rabbit against rat HL (anti-HL) and in goat against rat LPL (anti-LPL). As an alternative, we analyzed HL activity in the presence of 1 M NaCl, a condition known to inhibit LPL activity in humans. The assays were validated using plasma samples from wild-type and HL-deficient C57BL/6 mice. We now show that the use of 1 M NaCl for the inhibition of plasma LPL activity in mice may generate incorrect measurements of both LPL and HL activities. Our data indicate that HL can be measured directly, without heparin injection, in preheparin plasma, because virtually all HL is present in an unbound form circulating in plasma. In contrast, measurable LPL activity is present only in postheparin plasma. Both HL and LPL can be measured using the same assay conditions (low salt and the presence of apolipoprotein C-II as an LPL activator). Total lipase activity in postheparin plasma minus preheparin HL activity reflects LPL activity. Specific antibodies are not required.
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The tea plant Camellia sinesis is cultivated in >30 countries. Epidemiologic observations and laboratory studies have indicated that polyphenolic compounds present in tea may reduce the risk of a variety of illnesses, including cancer and coronary heart disease. Most studies involved green tea, however; only a few evaluated black tea. Results from studies in rats, mice, and hamsters showed that tea consumption protects against lung, forestomach, esophagus, duodenum, pancreas, liver, breast, colon, and skin cancers induced by chemical carcinogens. Other studies showed the preventive effect of green tea consumption against atherosclerosis and coronary heart disease, high blood cholesterol concentrations, and high blood pressure. Because the epidemiologic studies and research findings in laboratory animals have shown the chemopreventive potential of tea polyphenols in cancer, the usefulness of tea polyphenols for humans should be evaluated in clinical trials. One such phase 1 clinical trial is currently under way at the MD Anderson Cancer Center in collaboration with Memorial Sloan-Kettering Cancer Center. This study will examine the safety and possible efficacy of consuming the equivalent of ≥10 cups (≥2.4 L) of green tea per day. The usefulness of tea polyphenols may be extended by combining them with other consumer products such as food items and vitamin supplements. This “designer-item” approach may be useful for human populations, but it requires further study.
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The effects of the aqueous extracts of Welsh onion green leaves (WOE) on the expression of scavenger receptor class BI (SR-BI) and ATP-binding cassette A1 (ABCA1), the two high-density lipoprotein (HDL) receptors, presented in macrophage RAW 264.7 cells were investigated. WOE in the range of 0–0.5mg/ml increased the protein expression of ABCA1 and SR-BI by a dose- and time-dependent manner in macrophages. On the other hand, lipopolysaccharide (LPS) at 200ng/ml decreased ABCA1 and SR-BI protein expression, and WOE in the range of 0–1.0mg/ml blocked LPS-decreased ABCA1 and SR-BI protein expression. Quercetin and kaempferol, the two major flavonoids presented in WOE, in the range of 0–3.4μg/ml also showed an inductive effect on the ABCA1 and SR-BI protein and a protective effect under LPS stimulation. Furthermore, determined by reverse transcription-polymerase chain reaction (RT-PCR), WOE in the range of 0–1.0mg/ml increased the ABCA1 and SR-BI mRNA levels after 12h treatment. LPS also obviously decreased ABCA1 and SR-BI mRNA in RAW 264.7 cells. These LPS resulted mRNA inhibitions were also markedly prevented by the addition of WOE, quercetin and kaempferol, respectively. These results suggest that WOE and its two major flavonoids, quercetin and kaempferol; have potential effect on increasing HDL receptor expression in macrophages.
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An isocratic HPLC procedure was developed for simultaneous determination of six catechins, gallic acid, and three methylxanthines in tea water extract. A baseline separation was achieved on a Cosmosil C18-MS packed column with a solvent mixture of methanol/doubly distilled water/formic acid (19.5:80.2:0.3, v/v/v) as mobile phase. A gradient HPLC procedure was also provided for the separation of these tea components. The contents of catechins, gallic acid, and methylxanthines have been measured in infusions of a range of green tea, oolong tea, and pu-erh tea products sold and consumed in the China, Japan, and Taiwan. When 15 Chinese green tea and 13 Japanese green tea products were analyzed by the HPLC method, the mean levels of the total catechins, (−)-epigallocatechin 3-gallate, (+)-catechin, and caffeine were found to be very similar in these two groups, but other minor catechins such as (−)-epigallocatechin, (−)-epicatechin, and (−)-gallocatechin 3-gallate were found to be higher in Japanese green tea products, whereas (−)-epicatechin 3-gallate, gallic acid, theophylline, and theobromine were found to be higher in Chinese green tea products. Oolong tea products possessed lower levels of catechins, whereas pu-erh tea products contained negligible amounts of these constituents. The new HPLC method is rapid, reliable, and reproducible and should be highly recommended to tea industries for routine analysis of commercial tea samples. Keywords: Catechins; gallic acid; caffeine; theophylline; theobromine; green tea; oolong tea; paochong tea; pu-erh tea; black tea; isocratic HPLC
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Normal adult female rats fed a variety of supermarket foods in addition to lab chow rapidly gained weight and became obese compared to rats fed only lab chow. Group housing the animals in an enriched environment did not alter the development of dietary obesity, but housing the rats in activity wheels reduced, although did not prevent, the obesity. The dietary obese rats did not normally defend their excessive weights since they were less willing to eat quinine diets, worked less for food, failed to increase their activity when deprived, and regained their weight at a slower rate following a fast than did controls. The similarity between this behavioral pattern and that displayed by hypothalamic obese rats and overweight humans is discussed.
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We compared, across several physiological variables, rats most and least susceptible to develop obesity when given a high-fat diet. After 4 wk of eating a high-fat diet (60% of calories from fat), rats in the upper (obesity prone, OP) and lower (obesity resistant, OR) quartiles for weight gain were further studied. OP rats ate significantly more than OR rats, but this did not completely explain differences in their susceptibility to dietary obesity. No differences in 24-h energy expenditure were found between groups. OR rats had a significantly lower 24-h respiratory quotient, indicative of a greater relative proportion of fat oxidation and lower plasma levels of free fatty acids (FFA) than OP rats. Thus the ability to avoid dietary obesity produced by a high-fat diet may depend on an ability to increase fat oxidation in response to increased fat intake. Insulin sensitivity, measured by a euglycemic insulin clamp, was significantly higher in OR than OP rats. We cannot determine from these data whether insulin resistance developed as a consequence of elevated FFA levels or whether the ability to oxidize FFA declined as a result of development of insulin resistance. In summary, we propose that rats able to resist becoming obese on a high-fat diet have the ability to adjust the composition of fuel oxidized to the fuel composition of the diet with a minimum increase in body fat. The specific mechanisms by which this occurs are unknown but may be related to effects of diet on insulin sensitivity.
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Chronic diet-induced obesity developed in 50-60% of male Sprague-Dawley rats fed a relatively high-calorie diet for 90 days. The remaining rats decreased their caloric intake and resisted the development of obesity. All male Fischer F-344 rats fed this diet for 85 days became obese but to only half the degree of the obese Sprague-Dawley rats. The development of chronic obesity in both rat strains was associated with decreased norepinephrine (NE) levels in hearts and aortas and decreased NE turnover in aortas compared with chow-fed controls. However, 40-50% of the Sprague-Dawley rats did not become obese on this diet, yet showed similar findings suggesting an effect of dietary composition on sympathetic function. The more profoundly obese Sprague-Dawley rats additionally showed decreased or absent NE turnover in their hearts and pancreases. Since sympathetic function in both strains of rats with diet-induced obesity was either depressed or normal, it appears unlikely that the initial enhancement of sympathetic activity seen during short-term overfeeding plays an important continuing role in combating more chronic states of obesity in the rat.
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Several studies show a relationship between abdominal obesity and cardiovascular diseases, partially mediated through an altered metabolism of dyslipidemia. The present study was aimed at testing the robustness of this association across three contrasted populations and at assessing the performances of abdominal obesity as a screening tool for dyslipidemia. Data were drawn from three population health surveys recently conducted in two regions of a developed country (Switzerland, mostly of Caucasian origin, n = 2650) and in a less developed country (Seychelles, Indian Ocean, mostly of black descent, n = 806). Dyslipidemia was defined as a ratio of total cholesterol to high-density lipoprotein cholesterol (TC-HDL) greater than 5. Two anthropometric circumference measurements, waist-to-hip ratio (WHR) and waist circumference (WC), were used to define abdominal obesity either as WHR >/= 0.9 in men and WHR >/= 0.8 in women or as WC >/= 94 cm and WC >/= 80 cm, respectively. A consistent direct association between abdominal obesity and dyslipidemia (odds ratios varying from 1.85 to 4.56) was found in the three populations, independently of gender, age, body mass index, blood pressure, and smoking. This consistency across ethnicities and environments strengthens the hypothesis of a common etiopathological mechanism. The sensitivity for detecting dyslipidemia was generally higher for abdominal obesity, based on either WHR or WC, than for criteria based on the other risk factors under study. In addition, the sensitivity was higher in the study populations with a low prevalence of dyslipidemia (Swiss women and Seychellois of both sexes) than in the others. These findings support that WHR and WC may be useful as simple and inexpensive screening tools to select individuals eligible for more sophisticated and costly serum lipid determinations, especially in developing countries.
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The tea plant Camellia sinesis is cultivated in >30 countries. Epidemiologic observations and laboratory studies have indicated that polyphenolic compounds present in tea may reduce the risk of a variety of illnesses, including cancer and coronary heart disease. Most studies involved green tea, however; only a few evaluated black tea. Results from studies in rats, mice, and hamsters showed that tea consumption protects against lung, forestomach, esophagus, duodenum, pancreas, liver, breast, colon, and skin cancers induced by chemical carcinogens. Other studies showed the preventive effect of green tea consumption against atherosclerosis and coronary heart disease, high blood cholesterol concentrations, and high blood pressure. Because the epidemiologic studies and research findings in laboratory animals have shown the chemopreventive potential of tea polyphenols in cancer, the usefulness of tea polyphenols for humans should be evaluated in clinical trials. One such phase 1 clinical trial is currently under way at the MD Anderson Cancer Center in collaboration with Memorial Sloan-Kettering Cancer Center. This study will examine the safety and possible efficacy of consuming the equivalent of > or =10 cups (> or =2.4 L) of green tea per day. The usefulness of tea polyphenols may be extended by combining them with other consumer products such as food items and vitamin supplements. This "designer-item" approach may be useful for human populations, but it requires further study.
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Beneficial health effects of tea have been demonstrated in animal experiments and some human studies. The two most extensively investigated diseases are cancer and heart disease. Although mechanisms of protective activity of tea against these diseases have been proposed, there are inconsistencies in the relationship between tea consumption and the risk of these diseases in humans. The bioavailability of active components is beginning to be understood, but further research is required to determine whether the results from animal studies are applicable to humans. Also discussed are the possible effects of tea in increasing thermogenesis and bone density as well as decreasing risk of cataracts and arthritis. The potential health benefits of tea consumption warrant further investigation.
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The last decade has witnessed a major reassessment of our perceptions about the acute coronary syndromes. Today, we recognize that thrombosis underlies most acute complications of atherosclerosis, notably unstable angina and acute myocardial infarction. A consensus has emerged that inflammation plays a decisive role in the pathophysiology of these acute thrombotic events (Figure 1). Knowledge of the underlying mechanisms has increased substantially since this topic was last reviewed in these pages 6 years ago. The present article provides an update of this rapidly moving field. Figure 1. Initiation, progression, and complication of human coronary atherosclerotic plaque. Top, Longitudinal section of artery depicting “timeline” of human atherogenesis from normal artery (1) to atheroma that caused clinical manifestations by thrombosis or stenosis (5, 6, 7). Bottom, Cross sections of artery during various stages of atheroma evolution. 1, Normal artery. Note that in human arteries, the intimal layer is much better developed than in most other species. The intima of human arteries contains resident smooth muscle cells often as early as first year of life. 2, Lesion initiation occurs when endothelial cells, activated by risk factors such as hyperlipoproteinemia, express adhesion and chemoattractant molecules that recruit inflammatory leukocytes such as monocytes and T lymphocytes. Extracellular lipid begins to accumulate in intima at this stage. 3, Evolution to fibrofatty stage. Monocytes recruited to artery wall become macrophages and express scavenger receptors that bind modified lipoproteins. Macrophages become lipid-laden foam cells by engulfing modified lipoproteins. Leukocytes and resident vascular wall cells can secrete inflammatory cytokines and growth factors that amplify leukocyte recruitment and cause smooth muscle cell migration and proliferation. 4, As lesion progresses, inflammatory mediators cause expression of tissue factor, a potent procoagulant, and of matrix-degrading proteinases that weaken fibrous cap of plaque. 5, If fibrous cap ruptures at point of weakening, coagulation factors …
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Compelling evidence from meta-analysis of a number of clinical studies on a large aggregate of patients has established an increased level of triglycerides as an independent risk factor for atherosclerotic heart disease. The finding of triglyceride-rich lipoproteins in human atheromata has provided substantial pathophysiologic evidence for a direct role in atherogenesis. Hypertriglyceridemia is commonly embedded in the context of a metabolic syndrome that includes central obesity, insulin resistance, low levels of HDL cholesterol, and often hypertension. Hypertriglyceridemia also appears to underlie the phenomenon of small dense LDL in most instances. Therapeutic interventions must be directed at underlying obesity, insulin resistance, and diabetes when present, as well as addressing metabolic determinants of dyslipidemia per se. Diet, exercise, weight loss, and avoidance of alcohol are the cornerstones of treatment. The choice of medication should be based on the lipoprotein phenotype. Niacin, fibric acid derivatives, and omega-3 fatty acids are most useful in treating severe hypertriglyceridemia. HMG-CoA reductase inhibitors are useful in some phenotypes with moderately increased triglyceride levels. Evidence from a number of clinical trials indicates that mitigation of risk of coronary heart disease, and possibly stroke, can be effected by reducing levels of plasma triglycerides.
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The effects of pu-erh tea, which is prepared by fermentation of tea, on oxidative damage and nitric oxide scavenging, compared with various other brands of tea were investigated. The total antioxidant activity was determined using the Trolox equivalent antioxidant capacity (TEAC) assay. The results showed that TEAC values of the 200 microg/mL water extracts of pu-erh tea (WEPT), green tea, oolong tea, and black tea were 86.3, 85.3, 87.4, and 80.3 (microg/mL), respectively, indicating that WEPT showed a significant antioxidant activity. WEPT, like green tea extract, oolong tea extract, and black tea extract, exhibited a remarkable protective effect in lipid (liposome) and nonlipid (protein and deoxyribose) model systems, implying that it is an inhibitor of lipid and nonlipid oxidative damage. It also exhibited metal-binding ability, reducing power, and scavenging effect for free radicals. Moreover, WEPT showed a decreasing effect on nitric oxide production of lipopolysaccharide-induced RAW 264.7 macrophages. In addition, the results revealed that epicatechin (EC), flavonoid, ascorbic acid, and polyphenolic compounds are present in WEPT, which may partially account for the protective effect on oxidative damage. Thus, WEPT may have potential as an antioxidant and as a nitric oxide scavenging agent.
Article
Long-term feeding of tea catechins suppressed body fat accumulation in high-fat diet-induced obesity in mice, and that their effects might be attributed, at least in part, to the activation of hepatic lipid metabolism. Consecutive intake of tea catechins (588 mg/day) reduced body fat, especially abdominal fat in humans. These results demonstrate that intake of tea catechins is beneficial for body fat accumulation.
Article
The four major commercial teas, oolong, black, pu-erh, and green teas, have been manufactured in southeast Asia. In this study, we evaluated the growth suppressive and hypolipidemic effect of these four different tea leaves by oral feeding to male Sprague-Dawley rats for 30 weeks. The results showed that the suppression of body weights of tea leaves-fed groups were in the order: oolong tea > pu-erh tea > black tea > green tea. Pu-erh tea and oolong tea could lower the levels of triglyceride more significantly than that of green tea and black tea, but pu-erh tea and green tea were more efficient than oolong tea and black tea in lowering the level of total cholesterol. In lipoprotein, 4% pu-erh tea could increase the level of HDL-C and decrease the level of LDL-C, but other teas simply decrease the levels of both. The activity of antioxidant enzyme SOD is increased in all tea-fed groups as compared to the basal diet-fed group. Finally, relative weight ratios of liver to epididylmal adipose tissue were lower in feeding oolong tea and pu-erh tea groups. On the basis of these findings, it seemed that the fully fermented pu-erh and black tea leaves and partially fermented oolong tea leaves were more effective on their growth suppressive and hypolipidemic effects as compared to the nonfermented green tea leaves.
Article
Although high-density lipoproteins (HDL) possess many features that contribute to the association between elevated HDL cholesterol and protection from atherosclerosis, these lipoproteins may be modified in certain individuals and/or circumstances to become proinflammatory. The ability of HDL to inhibit or paradoxically to enhance vascular inflammation, lipid oxidation, plaque growth, and thrombosis reflects changes in specific enzyme and protein components. The anti-inflammatory and proinflammatory functional properties of HDL can now be assessed using cell-based and cell-free assays. Acute or chronic systemic inflammation and the metabolic syndrome appear to render HDL proinflammatory. In contrast, statins and experimental agents such as apolipoprotein A-1 mimetics render HDL more anti-inflammatory. Functional characterization of HDL is a promising method for enhanced assessment of cardiovascular risk and effectiveness of risk reduction.
Article
Green tea catechins (GTCs) are polyphenolic flavonoids formerly called vitamin P. GTCs, especially (-)-epigallocatechin-3-gallate (EGCG), lower the incidence of cancers, collagen-induced arthritis, oxidative stress-induced neurodegenerative diseases, and streptozotocin-induced diabetes. Also, inhibition of adipogenesis by green tea and green tea extract has been demonstrated in cell lines, animal models, and humans. The obesity-preventive effects of green tea and its main constituent EGCG are widely supported by results from epidemiological, cell culture, animal, and clinical studies in the last decade. Studies with adipocyte cell lines and animal models have demonstrated that EGCG inhibits extracellular signal-related kinases (ERK), activates AMP-activated protein kinase (AMPK), modulates adipocyte marker proteins, and down-regulates lipogenic enzymes as well as other potential targets. Also, the catechin components of green tea have been shown to possess anti-carcinogenic properties possibly related to their anti-oxidant activity. In addition, it was shown that dietary supplementation with EGCG could potentially contribute to nutritional strategies for the prevention and treatment of type 2 diabetes mellitus. In this review, the biological activities and multiple mechanisms of EGCG in cell lines, animal models, and clinical observations are explained.
Article
A water-soluble extract of a traditional Chinese fermented black tea, pu-ehr, decomposes bile acid cholesterol micelles. This black tea extract (BTE) was studied to see if it could decrease the postprandial elevation of blood cholesterol levels after a single administration in ddY mice. It was found that BTE (0.3 g/kg) significantly decreased the postprandial rise in blood cholesterol levels after oral administration of cholesterol (130 mg/kg). A non-fermented tea (i.e. green tea) extract did not prevent the postprandial increase in blood cholesterol. In a subsequent study, 5-week-old Sprague-Dawley (SD) rats were fed BTE for 3 weeks, following which a dose-dependent and significant decrease in serum total cholesterol levels (1.36 mmol/L, 0.1% BTE, p < 0.05) was found and also in renal fat weight (0.3% BTE, p < 0.05). LDL cholesterol levels (0.51 mmol/L, 0.1% BTE, p < 0.05) were also significantly decreased. There were no significant changes in the weights of other organs or in the serum levels of other clinical markers. Thus, BTE has a specific antihypercholesterol effect in rodents, which might potentially aid in the management of hyperlipidaemia in man.
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