Black Tea Extract and its Thearubigins Relieve the Sildenafil‐Induced Delayed Gut Motility in Mice: A Possible Role of Nitric Oxide

In this study we hypothesize that a standardized black tea aqueous extract (BTE) and thearubigins, its main polyphenolic pigments, will improve sildenafil‐induced delay in gastric emptying (GE) and small intestinal transit (SIT) in mice. Twenty groups of mice (n = 8) were given a phenol red meal, and three sets of experiments were performed. In the first and second sets, effects of different concentrations of BTE, thearubigins (TRs), and sildenafil (SLD), alone and in combinations, on GE and SIT were measured. In the third set, influence of n _ω‐Nitro‐l ‐arginine methyl ester hydrochloride (l ‐NAME) pretreatment on effects of these treatments was tested. Black tea extract (3% and 4.5%) and thearubigins (50 and 60 mg/kg) dose‐dependently increased GE and SIT, whereas BTE 6% and thearubigins 70 mg/kg did not affect them. Sildenafil dose‐dependently reduced both GE and SIT. Combination of metoclopramide, BTE 4.5%, thearubigins 60, or l ‐NAME with sildenafil (5 mg/kg) reversed its motility‐delaying effects. Pretreatment with l ‐NAME followed by BTE 4.5%, thearubigins 60, BTE 4.5% + sildenafil 5, or thearubigins 60 + sildenafil 5 only partially affected the accelerating effects of BTE 4.5% and thearubigins 60. In conclusion, a standardized BTE and its thearubigins improve the sildenafil‐induced delayed gut motility in mice. This improvement was partially blocked by l ‐NAME suggesting a possible role of nitric oxide. Thus, BTE 4.5% or TRs 60 mg/kg solution could be considered a reliever therapy for the sildenafil‐induced dyspepsia. Copyright © 2014 John Wiley & Sons, Ltd.     

Extract of black tea (pu-ehr) inhibits postprandial rise in serum cholesterol in mice, and with long term use reduces serum cholesterol and low density lipoprotein levels and renal fat weight in rats

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.     

Weight Reduction Effect of Puerh Tea in Male Patients with Metabolic Syndrome

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/m² in the Puerh tea group (p = 0.076) versus 0.09 kg/m² 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.     

Antilipogenic effect of green tea extract in C57BL/6J‐Lepob/ob mice

The objective of this study was to determine the effects of green tea extract (GTE) on lipid metabolism in obese animal models. Male C57BL/6J‐Lepob/ob mice were divided into control and GTE (0.05 g/100 g diet) groups, which were fed a high‐fat (20 g/100 g diet) diet for 12 weeks. Supplementation of GTE significantly reduced (p < 0.01) perirenal and total white adipose tissue weights compared with the control group. Also, the plasma HDL‐cholesterol level was significantly higher in the GTE group than in the control group, therefore the GTE group showed a higher HDL‐cholesterol/total‐cholesterol ratio (HTR) and lower atherogenic index (AI) level than the control group. A reduction of hepatic triglyceride content and adipose tissue weight in the GTE group was related to the suppression of enzyme activities for fatty acid synthesis (glucose‐6‐phosphate dehydrogenase and malic enzyme) without affecting fatty acid oxidation enzyme (β‐oxidation and carnitine palmitoyl transferase) activities in hepatic and adipose tissue. The current results showed that supplementation of green tea extract is beneficial for antiobesity by the suppression of lipogenesis via regulation of related enzyme activities in hepatic and adipose tissue. Copyright © 2008 John Wiley & Sons, Ltd.     

Protective action of aqueous black tea (Camellia sinensis) extract (BTE) against ovariectomy‐induced oxidative stress of mononuclear cells and its associated progression of bone loss

The protective action of aqueous black tea extract (BTE) against ovariectomy‐induced oxidative stress of mononuclear cells and its associated progression of bone loss was demonstrated in this study. Eighteen female adult 6‐month‐old Wistar albino rats were divided into three groups: sham‐control (A), bilaterally ovariectomized (B) and bilaterally ovariectomized + BTE supplemented (C). Studies included the measurement of oxidative (nitric oxide, lipid peroxidation) and antioxidative (superoxide dismutase, catalase) markers, inflammatory cytokines (IL‐6, TNF‐α), osteoclast differentiation factor (RANKL) and bone resorption markers (tartrate‐resistant acid phosphatase and hydroxyproline). Also quantitative histomorphometry and histological studies were undertaken. The bone breaking force was measured. The results indicate that BTE was effective in preserving and restoring skeletal health by reducing the number of active osteoclasts. Such changes with BTE supplementation were steadily linked with the reduced oxidative stress of mononuclear cells, serum levels of bone resorbing cytokines, osteoclast differentiation factor and resorption markers. The results of the bone breaking force, histological and histomorphometric analyses further supported the hypothesis. This study suggests that BTE has both protective and restorative actions against ovariectomy‐induced mononuclear cell oxidative stress and associated bone loss. Copyright © 2009 John Wiley & Sons, Ltd.     

Acute and subchronic oral toxicities of Pu-erh black tea extract in Sprague-Dawley rats

Ethnopharmacological relevance

Pu-erh black tea, which is obtained by first parching crude green tea leaves and then undergoes secondary fermentation with microorganisms, has been believed to be beneficial beverages for health for nearly 2000 years in China, Japan and Taiwan area. But its potential toxicity when administered at a high dose as concentrated extracts has not been completely investigated.

The aim of the study

The present study was aimed at evaluating potential toxicity of Pu-erh black tea extracts (BTE) from acute and sub-chronic administration to male and female Sprague-Dawley (SD) rats.

Materials and methods

A single BTE dose of 10,000 mg/kg of body weight was administered by oral gavage for acute toxicity in SD rats. Four groups (10 males and 10 females per group) of dose levels of 1250, 2500, and 5000 mg/kg/day of the test article, as well as controls (distilled water) were tested as the subchronic toxicity study.

Results

No deaths and signs of toxicity occurred during the 14 days of the study. There were no test article related mortalities, body weight gain, feed consumption, clinical observation, organ weight changes, gross finding, clinical or histopathological alterations during the 91-day administration.

Conclusions

The LD₅₀ of BTE can be defined as more than 10,000 mg/kg, and a dose of 5000 mg/kg/day was identified as the no-observed-adverse-effect-level (NOAEL) in this study.     

Betulinic acid has an inhibitory effect on pancreatic lipase and induces adipocyte lipolysis

Betulinic acid is a pentacyclic triterpenic acid that exists naturally in many kinds of food and has many biological functions. The present study investigated the antiobesity properties of betulinic acid and possible mechanisms by which betulinic acid functions. To examine the antilipase function of betulinic acid, the ability of betulinic acid to inhibit pancreatic lipase activity in vitro and to prevent the elevation of plasma triacylglycerol levels was tested after oral administration of a lipid emulsion in rats. In addition, the lipolytic effects of betulinic acid were assayed in rat adipose tissues. The activity of cAMP‐dependent phosphodiesterase was also measured in vitro. Betulinic acid inhibited pancreatic lipase activity in a dose‐dependent manner at concentrations of 1.5–100 µ m (IC₅₀ value of 21.10 µ m ) and prevented the elevation of plasma triacylglycerol levels 2 h after oral administration of the lipid emulsion at a dose of 100 mg/kg. In addition, betulinic acid had a strong lipolytic effect, which was mediated by cAMP‐dependent phosphodiesterase inhibition. In conclusion, betulinic acid may exert antiobesity effects by directly inhibiting pancreatic lipase, which would prevent the absorption of lipid from the small intestine. In addition, it was found that betulinic acid may further accelerate fat mobilization by enhancing the levels of lipolysis in adipose tissues. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of aqueous extracts of black and green teas in arsenic‐induced toxicity in rabbits

Arsenic causes oxidative stress in the body. Its administration (3 mg/kg/day) for 14 days in rabbits resulted in a significant reduction of whole blood glutathione (GSH), and elevation of thiobarbituric acid reactive substances (TBARS) and the index of nitrite/nitrate (NOx) levels. These are the markers of oxidative stress. Both black tea (BT) and green tea (GT) (Camellia sinensis), when administered to the arsenic‐treated rabbits for 14 days, caused a significant elevation of the depleted GSH level to 53.12% and 57.47%, respectively. On the contrary, in the placebo group the level was 26.59%. The BT and GT reduced the elevated TBARS level to 43.27% and 62.28%, respectively, whereas the corresponding level in the placebo groups was 21.24%. The NOx levels were also reduced to 63.62%, 67.67% and 58.94% in BT, GT and the placebo groups, respectively. When arsenic and black tea were given concurrently to another group the results were even more pronounced. The polyphenol components of black and green tea were 27.69% and 29.71% of the dry weight of the total extracts, respectively. These results indicated that arsenic‐induced toxicities in rabbits were significantly reversed by the black and green tea polyphenols. The greater activity of green tea than that of black tea correlates with the slightly higher content of polyphenols in green tea. Copyright © 2009 John Wiley & Sons, Ltd.     

Korean red ginseng (Panax ginseng) improves insulin sensitivity in high fat fed Sprague-Dawley rats

Many studies have documented that ginseng has antidiabetic and antiobesity effects, but the mechanism of the effects has not been elucidated. The aim of this study was to determine the effect of Korean red ginseng (KRG, Panax ginseng) and investigate the mechanism of antidiabetic and antiobesity effects in obese insulin resistant animal models. Sprague‐Dawley (SD) rats were divided into three groups: a control group (group I) fed a normal diet, another group (group II) fed only high fat diet (HFD) and a third group (group III) fed HFD with KRG (200 mg/kg, oral) for 18 weeks. The body weight, food intake, adipose tissues, liver, kidney, pancreas, adiponectin, and leptin were measured. Blood glucose, insulin tolerance test, and hyperinsulinemic euglycemic clamp test were investigated. A significant weight reduction, especially fat mass reduction, was observed in the KRG treated group. Increased insulin sensitivity was found in the KRG treated group. We observed increased insulin signalling, increased phosphorylation of IR, IRS‐1, Akt, and membranous GLUT4 in muscle by Western blotting assay. In conclusion, KRG may have antidiabetic and antiobesity effects due to partly increased insulin sensitivity by increased adipokine and partly enhanced insulin signalling. Copyright © 2011 John Wiley & Sons, Ltd.     

Vitamin C increases the fecal fat excretion by chitosan in guinea‐pigs,thereby reducing body weight gain

The aims of this study were to investigate the antiobesity properties of chitosan on its own, as well as in the presence of vitamin C, in vivo. Hartley guinea‐pigs were divided into Control (normal diet), F‐control (high fat diet), Chitosan (high fat diet with 5.0% chitosan) and Chito‐vit C (high fat diet with 5.0% chitosan containing 0.5% vitamin C) groups, respectively. The effects of chitosan, both alone and in the presence of vitamin C, on body weight, total fecal weight, fecal composition and plasma lipid level were studied for 5 weeks. The results of this study indicated that the fat‐binding and water‐holding capacity of chitosan might decrease body weight by reducing the absorption of cholesterol and fat, subsequently increasing total fecal weight, fecal fat excretion and fecal water excretion. Vitamin C increased the fecal fat excretion by chitosan in guinea‐pigs, thereby reducing body weight gain. Copyright © 2010 John Wiley & Sons, Ltd.     

Evaluation of reproductive and developmental toxicities of Pu-erh black tea (Camellia sinensis var. assamica) extract in Sprague Dawley rats

Ethnopharmacological relevance

Pu-erh black tea, which is obtained by first parching crude green tea leaves and followed by secondary fermentation with microorganisms, has been believed to be beneficial beverages for health in PR China. But its potential toxicity when administered at a high dose as concentrated extract has not been completely investigated.

Aim of the study

The present study was aimed at evaluating potential reproductive and developmental toxicities of Pu-erh black tea extract (BTE) in Sprague Dawley rats.

Materials and methods

Growing rats were given BTE by gavage at levels of 0, 200, 700 and 2500 mg/kg/day as the F₀ generation in reproductive toxicity study. Additionally, BTE was administered to mate female rats from gestation day 0.5 through 19.5 at the doses of 0, 200, 700 and 2500 mg/kg/day to evaluate the developmental toxicity.

Results

In the reproductive toxicity study, only 2500 mg/kg/day BTE reduced the body weight gain and altered the relative organ weights including testes, prostata and ovary both for F₀ parents and F₁ offspring compared to the controls. High dose of BTE (2500 mg/kg/day) administration caused developmental disturbances in embryo-to-foetus period including resorbed embryos, decreased embryo size and skeletal anomalies.

Conclusion

In conclusion, the no-observed-adverse-effect level of BTE is 700 mg/kg/day both for reproductive toxicity and developmental toxicities.     

不同茶叶及茶多酚对高脂饲料致大鼠脂肪肝的影响

目的:考察不同产地绿茶、红茶以及绿茶多酚对高脂饲料致大鼠脂肪肝的影响.方法:大鼠喂饲高脂饲料制备大鼠脂肪肝模型,喂饲含不同茶叶或茶多酚的高脂饲料,观察体重变化、睾丸脂肪垫重量、血清TG和TC、肝脏脂肪性变、肝匀浆甘油三酯和胆固醇含量.结果:各受试物组睾丸脂肪垫重量均较模型对照组减轻,云南绿茶组和四川绿茶组肝匀浆甘油三酯和胆固醇均明显低于模型对照;茶多酚组肝匀浆甘油三酯也明显低于模型对照组,但高于云南绿茶组和四川绿茶,茶多酚组肝匀浆胆固醇低于模型对照组,但明显高于云南绿茶组和四川绿茶组;云南红茶组肝匀浆甘油三酯和胆固醇与模型对照组相当.结论:云南绿茶和四川绿茶均对高脂饲料致大鼠脂肪肝的形成有明显抑制作用;茶多酚也有一定作用;但云南红茶作用不明显.     

Lapacho Tea (Tabebuia impetiginosa) Extract Inhibits Pancreatic Lipase and Delays Postprandial Triglyceride Increase in Rats

Earlier work in our laboratory indicated that ethanolic extracts of Tabebuia impetiginosa, Arctium lappa L., Calendula officinalis, Helianthus annuus, Linum usitatissimum and L. propolis, inhibit pancreatic lipase in vitro. In a follow‐up study we assessed their effects on plasma triglycerides in rats fed on a fatty meal. Extracts, orlistat or only ethanol were given orally to the rats together with the test meal and the rate of increase of postprandial triglycerides was assessed over 4 h. Clearing of the triglycerides from the blood compartment was abolished by inhibiting lipoprotein lipase with Triton WR‐1339. Our results showed that out of all the extracts, the bark of Tabebuia impetiginosa led to a significant delay in the postprandial increase of plasma triglycerides. However, lapachol, which is contained in the bark of Tabebuia impetiginosa and soluble in ethanol, had no lipase inhibitory effect in vitro and hence this substance did not seem to mediate the pertinent effect. Copyright © 2012 John Wiley & Sons, Ltd.     

Chamomile and Marigold Tea: Chemical Characterization and Evaluation of Anticancer Activity

With the aim to evaluate the selectivity in the antitumor action, the cytotoxic activity of chamomile and marigold tea was tested against various malignant cell lines and against healthy immunocompetent peripheral blood mononuclear cells (PBMC). Chemical profiles of chamomile and marigold infusions and decoctions were analyzed by liquid chromatography/mass spectrometry; their total phenolic content and radical scavenging activity were determined, too. Results from present research demonstrate that chamomile and marigold tea exert selective dose‐dependent cytotoxic action against target cancer cells. It is noteworthy that cytotoxicity of tea prepared from Calendula officinalis is remarkably higher in comparison to that from Matricaria recutita tea. The cytotoxic effect of chamomile tea is very weak to healthy PBMC, while the effect of marigold tea on PBMC is more pronounced. Marigold tea exerts highly selective antitumor effect especially to melanoma Fem‐x cells in comparison to the action to normal healthy PBMC. Chemical analyses show that dominant phenolic compounds in examined infusions and decoctions are flavonoid glycosides and hydroxycinnamic acid derivatives. There are no considerable differences in total phenolic content and antioxidant activity between examined infusions. Antitumor potential of chamomile and marigold tea should be further investigated. Copyright © 2012 John Wiley & Sons, Ltd.     

A Randomized,Double‐blind,Placebo‐controlled Clinical Trial Examining the Effects of Green Tea Extract on Systemic Lupus Erythematosus Disease Activity and Quality of Life

Antiinflammatory and immunomodulatory benefit of green tea (Camellia sinensis) in autoimmune disease has been proven in recent studies. The objective of this study was to assess the effects of green tea on disease activity and quality of life in systemic lupus erythematosus patients. A randomized controlled trial on subjects with lupus was conducted, and 68 patients in the age range of 39.1 ± 10.3 years and body mass index of 25.7 ± 5.21 kg/m² completed the 12‐week study. Patients were randomly divided into two groups of intervention (1000 mg green tea extract, two capsules/day) and control (1000 mg of starch, two capsules/day). Main outcome measure, systemic lupus erythematosus disease activity, was assessed by the systemic lupus erythematosus disease activity index at the first and after 3 months of intervention. In addition, patient's quality of life was evaluated by short form of quality‐of‐life questionnaire at baseline and after 3 months. Green tea extract supplementation significantly reduced disease activity in lupus patients (p < 0.004); in addition, it significantly increased the vitality (p < 0.006) and general health (p < 0.01). This study showed that daily consumption of green tea extracts for 12 weeks improves the systemic lupus erythematosus disease activity as well as some aspects of quality of life. Copyright © 2017 John Wiley & Sons, Ltd.     

Pancreatic Lipase Inhibitory Activity of Phlorotannins Isolated from Eisenia bicyclis

Pancreatic lipase is a potential therapeutic target for the treatment of diet‐induced obesity in humans. In an ongoing search for new pancreatic lipase inhibitors from natural sources, a methanolic extract of marine brown algae, Eisenia bicyclis, showed a significant inhibitory effect against pancreatic lipase. Bioassay‐guided isolation of this methanolic extract using a pancreatic lipase inhibitory assay led to the isolation and identification of six known phlorotannins: eckol (1), fucofuroeckol A (2), 7‐phloroeckol (3), dioxindehydroeckol (4), phlorofucofuroeckol A (5), and dieckol (6). The structures were established on the basis of nuclear magnetic resonance and mass spectrometry spectroscopic data interpretation. Among the isolated phloroglucinol polymers, compounds 2 and 3 showed potent inhibitory effects on pancreatic lipase with IC₅₀ values ranging from 37.2 ± 2.3 to 12.7 ± 1.0 μM, respectively. Copyright © 2012 John Wiley & Sons, Ltd.     

The effect of green tea ointment on episiotomy pain and wound healing in primiparous women: A randomized,double‐blind,placebo‐controlled clinical trial

The delayed healing of episiotomy wound and its associated pain is a major problem in obstetrics. Because green tea has analgesic and wound‐healing properties, the present study was conducted to determine the effect of green tea ointment on episiotomy pain and wound‐healing. The green tea extract was also standardized by measuring its Phenolic and flavonoid compounds, antioxidant activity, and one of its active components, that is, Epigallocatechin gallate. The present clinical trial was conducted on 99 primiparous women visiting Afzalipour Hospital in Kerman in 2015. The subjects were randomly divided into 3 groups, including a green tea ointment group, a placebo ointment group, and a routine care group. The 2 ointment groups smeared 2 cm of the green tea or placebo ointments onto their sutured area twice daily for a total of 10 days. The severity of pain was assessed in the subjects using the visual pain scale and wound‐healing using the Redness, Edema, Ecchymosis, Discharge, Approximation (REEDA) scale before the intervention and on the 5th and 10th days after delivery. To standardize the extract, Epigallocatechin gallate was measured by high‐performance liquid chromatography (HPLC). Phenolic and flavonoid compounds, as well as antioxidant activity of the extract were also determined by spectrometry methods. Before the intervention, no significant differences were observed between the 3 groups in terms of their personal and obstetric details (p > .05), the severity of pain (p = .118), and the REEDA score (p = .212). On the 5th and 10th days after delivery, the severity of pain was significantly lower in the green tea group than in the other 2 groups (p < .0001). The mean REEDA score on the 5th and 10th days showed a better and faster healing in the green tea group compared to the other 2 groups (p < .0001). Total content of phenolic and flavonoids contents of green tea were 74.2 mg/g Gallic acid equivalent and 16.3 mg/g Rutin equivalent, respectively, and its antioxidant capacity was 46% of b‐carotene. Green tea ointment appears to be effective in relieving episiotomy pain and improving wound‐healing in this study. Further studies are recommended to be conducted on the effectiveness and safety of the different doses of green tea ointment.