You definitely need tools!
Perfect coldbrew everytime
The ideal way to store your matcha
The ideal way to store your matcha
cancer-prevention
Matcha/green tea has for many centuries been regarded as an essential part of good health in Japan and China. Many believe it can help reduce the risk of cancer, and a growing body of evidence backs this up.
Recent Research Papers on
cancer-prevention
Antioxidant effects of Camellia sinensis L. extract in patients with type 2 diabetes
Author: Asta Spadiene and Nijole Savickiene and Liudas Ivanauskas and Valdas Jakstas and Andrejs Skesters and Alise Silova and Hiliaras Rodovicius
The prevalence of diabetes mellitus (DM) has dramatically increased in the past decade. Furthermore, increasing evidence from research shows that oxidative stress (OS) plays a crucial role in the pathogenesis of diabetes and in its complications. A search for ways to reduce oxidative damage has become the focus of interest for the majority of scientists. In this study, we determined the radical scavenging activity of single green tea constituents by using an on-line high performance liquid chromatography (HPLC)–2,2-diphenyl-1-picrylhydrazyl (DPPH) method and evaluated the antioxidant effects on type 2 diabetic patients by performing a double-blind, placebo-controlled study. Epigallocatechin gallate was identified as the most potent antioxidant, contributing approximately 50% of the total antioxidant capacity of green tea extract. We also found a statistically significant decrement of lipid peroxidation markers in patients treated with green tea extract after 9 months or after 18 months of follow-up. Overall, these findings are attractive for diabetic patients, helping them to keep a high level of performance and well-being, which ultimately may delay the time of disability and reduce mortality.
Green tea decoction improves glucose tolerance and reduces weight gain of rats fed normal and high-fat diet
Author: Chahira Snoussi and Robert Ducroc and Mohamed Hédi Hamdaoui and Karima Dhaouadi and Houda Abaidi and Francoise Cluzeaud and Corinne Nazaret and Maude Le Gall and André Bado
Green tea containing polyphenols exerts antidiabetic and antiobesity effects, but the mechanisms involved are not fully understood. In this study, we first analyzed and compared polyphenol compounds [epigallocatechin gallate (EGCG), epigallocatechin (EGC)] in decoction of green tea leaves versus usual green tea extracts. Second, the effects of acute (30 min) or chronic (6 weeks) oral administration of green tea decoction (GTD) on intestinal glucose absorption were studied in vitro in Ussing chamber, ex vivo using isolated jejunal loops and in vivo through glucose tolerance tests. Finally, we explore in rat model fed normal or high-fat diet the effects of GTD on body weight, blood parameters and on the relative expression of glucose transporters SGLT-1, GLUT2 and GLUT4. GTD cooked for 15 min contained the highest amounts of phenolic compounds. In fasted rats, acute administration of GTD inhibited SGLT-1 activity, increased GLUT2 activity and improved glucose tolerance. Similarly to GTD, acute administration of synthetic phenolic compounds (2/3 EGCG+1/3 EGC) inhibited SGLT-1 activity. Chronic administration of GTD in rat fed high-fat diet reduced body weight gain, circulating triglycerides and cholesterol and improved glucose tolerance. GTD-treated rats for 6 weeks display significantly reduced SGLT-1 and increased GLUT2 mRNA levels in the jejunum mucosa. Moreover, adipose tissue GLUT4 mRNA levels were increased. These results indicate that GTD, a traditional beverage rich in EGCG and EGC reduces intestinal SGLT-1/GLUT2 ratio, a hallmark of regulation of glucose absorption in enterocyte, and enhances adipose GLUT4 providing new insights in its possible role in the control of glucose homeostasis.
Green tea supplementation in mice mitigates senescence-induced changes in brain antioxidant abilities
Author: Yu-Wen Hsu and Chia-Fang Tsai and Hung-Chih Ting and Wen-Kang Chen and Cheng-Chieh Yen
Catechin composition of green tea extract and its anti-senescence effect was investigated with a study of senescence-related redox imbalance in the brains of aged mice. Oral administration of green tea extract at doses of 125, 625 and 1250 mg/kg for 4 weeks alleviated the senescence-mediated redox imbalance, as observed from the significantly reduced (p < 0.05) levels of thiobarbituric acid-reactive substances (TBARS) in the serum and increased glutathione (GSH) and total thiol levels in the plasma compared with that in the aged control group. Moreover, the activities of superoxide dismutase (SOD), catalase, glucose-6-phosphate dehydrogenase (G6PD), glutathione peroxidase (GSH-Px) and glutathione reductase (GSH-Rd) in the brain were also increased, whereas protein carbonyls were reduced. Taken together, these results clearly indicate that green tea extract exhibits potent protective effects against senescence-mediated redox imbalance in the brains of mice by inhibiting oxidative damage and increasing antioxidant enzyme activities.
Protective effects of polyphenols-enriched extract from Huangshan Maofeng green tea against CCl4-induced liver injury in mice
Author: Yanmang Cui and Xingbin Yang and Xinshan Lu and Jinwen Chen and Yan Zhao
The study was to characterize the polyphenolic composition, antioxidant properties, and hepatoprotective effects of a polyphenols-enriched extract (HMTP) from Huangshan Maofeng green tea. HPLC analysis showed that three predominantly polyphenolic compounds present in HMTP were epigallocatechin (271.2μg/mg extract), rutin (239.3μg/mg) and epicatechin (89.3μg/mg). HMTP was shown to exhibit strong scavenging activities against DPPH, O2−, and OH, and ferric-reducing antioxidant power in vitro. Administration of HMTP at 200, 400 and 800 mg/kg bw in mice prior to CCl4 injury significantly decreased the CCl4-induced elevation of serum ALT, AST and ALP activities, and prevented an increase in hepatic MDA levels (p < 0.05). Mice with HMTP pretreatment displayed a better profile of hepatosomatic index and the improved GSH-Px and SOD activities in the liver, relative to CCl4-intoxicated mice. Liver pathological observation also confirmed the protection on CCl4-caused histological alteration, suggesting that HMTP has potential to be explored as valuable hepatoprotective function food.
Delivery of green tea catechin and epigallocatechin gallate in liposomes incorporated into low-fat hard cheese
Author: Ali Rashidinejad and E. John Birch and Dongxiao Sun-Waterhouse and David W. Everett
The encapsulation of green tea catechin and epigallocatechin gallate (EGCG) in soy lecithin liposomes was examined at four concentrations (0%, 0.125%, 0.25% and 0.5% w/v), and inclusion in cheese at 0% and 0.25% w/v. The empty capsules had a mean diameter of 133nm and significantly (p < 0.05) increased with the addition of catechin or EGCG. Electron microscopy revealed the lamellae and central core of the liposomes. Addition of antioxidants gave a significant (p < 0.05) increase in the size of liposomes. Liposomes had surface potentials of −42.4 to −46.1 mV with no significant difference between treatments, suggesting stable liposome systems. High efficiency (>70%) and yield (∼80%) were achieved from the incorporation of catechin or EGCG inside the liposome structure. Addition of either antioxidant increased the liposome phase transition temperature (>50°C). Nanocapsules containing these antioxidants were effectively retained within a low-fat hard cheese, presenting a simple and effective delivery vesicle for antioxidants.
Su1201 The Expression of the 67 kDa Laminin Receptor (LR) or Green Tea Catechin Epigallocatechin-3-Gallate (EGCG) Receptor May Explain the Different Responses to EGCG in the Cell Lines Infected With H. pylori
Author: Prakitpunthu Tomtitchong and Jean E. Crabtree
Introduction: Epidemiological studies suggest epigallocatechin-3-gallate (EGCG), a natural product from green tea, may have a role in prevention of gastric atrophy and gastric cancer in Asian populations. Anyway, the diversity of results from in vivo studies was observed. Our group reported that EGCG inhibits H. pylori-induced upregulation of COX-2, EGF- related ligand and ADAMs transcripts, ERK phosphorylation and IL-8 activation in gastric and non-gastric epithelial cells. But we have simultaneously observed that EGCG can be a stimulator in some conditions. Recently, an EGCG specific receptor has been identified which is the 67 kDa laminin receptor (LR). We postulate that varying levels of the EGCG receptor, the 67 kDa LR, on different cell lines may modify the in vitro results determining the inhibitory effects of EGCG on cell signaling pathways. Methods: MKN28, MGEC, L5F11 and A431 epithelial cells were incubated with MLuC5 mouse monoclonal IgM before incuba- tion with TRITC-conjugated goat anti-mouse expression of the EGCG receptor. The 67 kDa laminin receptor (LR) or EGCG receptor was evident by immunofluorescence. Expression levels of EGCG receptor were compared with the different responses to EGCG among the four cell lines. Results: Strong expression of the EGCG receptor was evident on MKN28 cells but reduced levels were observed on L5F11 and A431 cells. MGEC cells show no expression of 67 kDa LR. Conclusions: Varying levels of the laminin or EGCG receptor may explain the different responses of the cell lines to EGCG and might explain variation of a role EGCG in prevention of H. pylori-induced gastric carcinogenesis.
Effect of consumption of catechin-rich green tea on pharmacokinetics of simvastatin in healthy volunteers
Author: S. Yamada and S. Misaka and K. Tanabe and A. Osano and K. Takeuchi and J.P. Werba and H. Watanabe
Background and purpose: Green tea has been reported to have various health benefits including cancer prevention and antiox- idative effect. Catechins, the main flavonoids in green tea, are considered to be potential components of these effects. Recently, a case report suggested that the consumption of catechin-rich green tea is associated with simvastatin intolerance. The present study aimed to evaluate the effect of catechin-rich green tea consumption on the pharmacokinetics of simvastatin lactone (SIM) and simvas- tatin acid (SVA), which are a prodrug and an active metabolite of simvastatin, respectively. Methods: In an open-label, two-way crossover study with 14 days washout, a single oral dose of 10mg SIM was administered to 12 healthy Japanese male volunteers (23–26 years old; body weight, 65.1±2.4 kg) after drinking of green tea (700mL/day, total catechinsof1080mg)orwater for2weeks. Bloodsampleswerecol- lected up to 24h after the administration. Plasma concentrations of SIM and SVA were determined using LC/MS/MS. Pharmacokinetic parameters were estimated by noncompartmental analysis. Results and discussion: Chronic consumption of catechin- rich green tea led to increases in the area under the plasma concentration-time curve (AUC0–∞) andmaximum concentration (Cmax) of SIM by 1.6- and 1.3-folds, respectively, as compared to water. No change was observed in the elimination half-life of SIM between green tea andwater, indicating that catechinsmainlymay inhibit SIMmetabolism in the intestine. In addition, green tea con- sumption significantly increased AUC0–∞ and Cmax of SVA by 1.5 and 1.6-folds, respectively, suggesting that green teamay affect not only the pharmacokinetics, but also the pharmacodynamics of SVA. Conclusion: The chronic consumption of catechin-rich green tea may cause the clinically relevant interaction with simvastatin.
Potentiality of chemometric approaches for the determination of (+)-catechin in green tea leaves at the surface of multiwalled carbon nanotube paste electrode
Author: Saeed Masoum and Mohsen Behpour and Fatemeh Azimi and Mohammad Hassan Motaghedifard
Differential pulse voltammetry technique assisted by chemometric methods such as multivariate curve resolution-alternating least squares (MCR-ALS) has been proposed as a valuable approach for (+)-catechin determination in the presence of gallic acid at the surface of multiwalled carbon nanotube paste electrode. Central composite design and response surface methodology were used to optimize the influencing parameters. To determine (+)-catechin in the presence of unexpected electroactive interference with a very high degree of overlapping, second-order electrochemical data were generated by changing the pulse height as an instrumental parameter. After potential shift correction, MCR-ALS results show that second-order calibration could be applied with great success for electroanalytical determination of highly overlapped electroactive species. The linear least-squares calibration curve based on the area under concentration profile was provided over the range of 0.10–2.69 μM for (+)-catechin, whereas detection limit was found to be 0.017 μM. Also in this study, the effect of rotational ambiguity associated with a particular MCR solution under a set of constraints was investigated.
Green tea (Camellia sinensis) extract inhibits both the metastasis and osteolytic components of mammary cancer 4T1 lesions in mice
Author: Ke-Wang Luo and Chun-Hay Ko and Grace Gar-Lee Yue and Julia Kin-Ming Lee and Kai-Kai Li and Michelle Lee and Gang Li and Kwok-Pui Fung and Ping-Chung Leung and Clara Bik-San Lau
Green tea (Camellia sinensis, CS), a kind of Chinese tea commonly consumed as a healthy beverage, has been demonstrated to have various biological activities, including antioxidation, antiobesity and anticancer. Our study aims to investigate the antitumor, antimetastasis and antiosteolytic effects of CS aqueous extract both in vitro and in vivo using metastasis-specific mouse mammary carcinoma 4T1 cells. Our results showed that treatment of 4T1 cells with CS aqueous extract resulted in significant inhibition of 4T1 cell proliferation. CS extract induced 4T1 apoptosis in a dose-dependent manner as assessed by annexin-V and propidium iodide staining and caspase-3 activity. Western blot analysis showed that CS increased the expression of Bax-to-Bcl-2 ratio and activated caspase-8 and caspase-3 to induce apoptosis. CS also inhibited 4T1 cell migration and invasion at 0.06–0.125 mg/ml. In addition, CS extract (0.6 g/kg, orally fed daily for 4 weeks) was effective in decreasing the tumor weight by 34.8% in female BALB/c mice against water treatment control (100%). Apart from the antitumor effect, CS extract significantly decreased lung and liver metastasis in BALB/c mice bearing 4T1 tumors by 54.5% and 72.6%, respectively. Furthermore, micro-computed tomography and in vitro osteoclast staining analysis suggested that CS extract was effective in bone protection against breast cancer-induced bone destruction. In conclusion, the present study demonstrated that the CS aqueous extract, which closely mimics green tea beverage, has potent antitumor and antimetastasis effects in breast cancer and could protect the bone from breast cancer-induced bone destruction.
Enhanced inhibition of prostate cancer xenograft tumor growth by combining quercetin and green tea
Author: Piwen Wang and Jaydutt V. Vadgama and Jonathan W. Said and Clara E. Magyar and Ngan Doan and David Heber and Susanne M. Henning
The chemopreventive activity of green tea (GT) is limited by the low bioavailability and extensive methylation of GT polyphenols (GTPs) in vivo. We determined whether a methylation inhibitor quercetin (Q) will enhance the chemoprevention of prostate cancer in vivo. Androgen-sensitive LAPC-4 prostate cancer cells were injected subcutaneously into severe combined immunodeficiency (SCID) mice one week before the intervention. The concentration of GTPs in brewed tea administered as drinking water was 0.07% and Q was supplemented in diet at 0.2% or 0.4%. After 6-weeks of intervention tumor growth was inhibited by 3% (0.2% Q), 15% (0.4% Q), 21% (GT), 28% (GT+0.2% Q) and 45% (GT+0.4% Q) compared to control. The concentration of non-methylated GTPs was significantly increased in tumor tissue with GT+0.4% Q treatment compared to GT alone, and was associated with a decreased protein expression of catechol-O-methyltransferase and multidrug resistance-associated protein (MRP)-1. The combination treatment was also associated with a significant increase in the inhibition of proliferation, androgen receptor and phosphatidylinositol 3-kinase/Akt signaling, and stimulation of apoptosis. The combined effect of GT+0.4% Q on tumor inhibition was further confirmed in another experiment where the intervention started prior to tumor inoculation. These results provide a novel regimen by combining GT and Q to improve chemoprevention in a non-toxic manner and warrant future studies in humans.
Other Popular Research Topics
Cognitive Function
Matcha consumption leads to much higher intake of green tea phytochemicals compared to regular green tea. Previous research on caffeine, L-theanine, and epigallocatechin gallate (EGCG) repeatedly demonstrated benefits on cognitive performance.
Learn More
Heart Health
According to Harvard Medical School, “lowering your risk of cardiovascular disease may be as easy as drinking green tea. Studies suggest this light, aromatic tea may lower LDL cholesterol and triglycerides, which may be responsible for the tea's association with reduced risk of death from heart disease and stroke.”
Learn More
Mental Health
Matcha contains an amino acid called L-theanine, which has been shown to reduce physiological and psychological stresses. L-theanine also improves cognition and mood in a synergistic manner with caffeine, and promotes alpha wave production in the brain
Learn More
Immunity
A recent study in the journal Proceedings of the National Academy of Sciences concluded that drinking matcha daily greatly enhanced the overall response of the immune system. The exceedingly high levels of antioxidants in matcha mainly take the form of polyphenols, catechins, and flavonoids, each of which aids the body’s defense in its daily struggles against free radicals that come from the pollution in your air, water and foods.
Learn More