Research Database
The only comprehensive database for clinical and medical research papers on the healthy benefits of matcha/green tea
Recent Research Papers on
mental-health
Author: Manal E.A. Elhalwagy and Nevine S. Darwish and Enass M. Zaher
The ameliorative effect of daily administrated dose of green tea extract (60 mg polyphenols/animal/day) was investigated on albino rats Rattus norvegicus (150–180 gm) intoxicated with 1/30 and 1/60 LD50 fenitrothion organophosphate insecticide for 28 days. Blood samples were taken at 14 and 28 days for further biochemical parameters. Histopathological studies were carried out in the liver and kidney at the end of the experiment. Significant inhibition in plasma cholinesterase (ChE), a biomarker of Ops, was recorded. Damage in the liver and kidney tissues was observed and confirmed with elevation of plasma alanine aminotransferase (ALT), aspartate aminotaransferase (AST), albumin, urea and creatinine, as well as an elevation in the oxidative stress (OS) marker malondialdehyde (MDA). Decrease in total glutathione (GSH) content in erythrocytes and fluctuation in glutathione S-transferase (GST) activity in plasma was also observed. Green tea supplementation (60 mg/animal/day) partially counteracts the toxic effect of fenitrothion on oxidative stress parameters and repairs tissue damage in the liver and kidney, especially when supplemented to 1/60 LD50 intoxicated animals depending on the duration. It seems that enzyme and metabolite markers of these organs need more time to be restored to the control level.
Author: Vilma Simões Pereira Panza and Elisabeth Wazlawik and Gustavo Ricardo Schütz and Leandro Comin and Karl Christian Hecht and Edson Luiz da Silva
Objective This study investigated the effects of the consumption of green tea (GT) for 7 d on biomarkers of oxidative stress in young men undergoing resistance exercise. Methods Fourteen subjects performed a bench press exercise (four sets, 10 to 4 repetitions) after undergoing a period without (control group) or with the intake of GT (GT group; 2 g of leaves in 200 mL of water, three times per day). Blood samples were obtained before and after exercise and analyzed for total antioxidant capacity (ferric reducing ability of plasma [FRAP]), total polyphenols, reduced glutathione (GSH), lipid hydroperoxide (LH) and thiobarbituric acid–reactive substances, creatine kinase (CK), aspartate aminotransferase (AST), xanthine oxidase (XO), hypoxanthine, and uric acid (UA). Results In the control group, exercise did not affect the values of LH, thiobarbituric acid–reactive substances, and FRAP, although it did reduce the levels of GSH (P < 0.05). In addition, exercise increased CK, AST, and XO activities, although it did not change the values for hypoxanthine or UA. Green tea reduced the postexercise concentration of LH and increased the values of total polyphenols, GSH, and FRAP. GT also inhibited a significant rise in CK and XO activities induced by exercise. Furthermore, GT decreased the AST activity and hypoxanthine and UA concentrations before and after exercise. The assessment of food consumption revealed that the participants had an unbalanced diet, particularly in relation to vitamin E and carotenoids. Conclusion Consumption of GT, a beverage rich in polyphenols, may offer protection against the oxidative damage caused by exercise, and dietary guidance for sports participants should be emphasized.
Author: Tae Il Kim and Yong Kyung Lee and Sang Gi Park and Im Seop Choi and Jung Ok Ban and Hyoung Kook Park and Sang-Yoon Nam and Young Won Yun and Sang Bae Han and Ki Wan Oh and Jin Tae Hong
Amyloid β (Aβ)-induced neurotoxicity is a major pathological mechanism of Alzheimer disease (AD). In this study, we investigated the inhibitory effect of l-theanine, a component of green tea (Camellia sinensis), on Aβ1-42-induced neuronal cell death and memory impairment. Oral treatment of l-theanine (2 and 4 mg/kg) for 5 weeks in the drinking water of mice, followed by injection of Aβ1-42 (2 μg/mouse, icv), significantly attenuated Aβ1-42-induced memory impairment. Furthermore, l-theanine reduced Aβ1-42 levels and the accompanying Aβ1-42-induced neuronal cell death in the cortex and hippocampus of the brain. Moreover, l-theanine inhibited Aβ1-42-induced extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase as well as the activity of nuclear factor κB (NF-κB). l-Theanine also significantly reduced oxidative protein and lipid damage and the elevation of glutathione levels in the brain. These data suggest that the positive effects of l-theanine on memory may be mediated by suppression of ERK/p38 and NF-κB as well as the reduction of macromolecular oxidative damage. Thus, l-theanine may be useful in the prevention and treatment of AD.
Author: Haim Shapiro and Shaul Lev and Jonathan Cohen and Pierre Singer
Sepsis is the overwhelming systemic response to infection of a normally sterile body compartment. Despite advances in elucidating its pathophysiology, severe sepsis remains a leading cause of death in the critically ill. Polyphenols are a family of chemicals found in food and beverages derived from plants, such as cocoa, green tea, turmeric, and soya, as well as in medicinal herbs. These phytochemicals exhibit anti-inflammatory and vasculoprotective properties in clinical and preclinical studies. The oral or systemic administration of polyphenols protects rodents from endotoxinemia and microbial sepsis. Under these circumstances, polyphenols reproducibly attenuate microvascular hyperpermeability, tissue infiltration by leukocytes, oxidative and nitrosative stress, tissue injury, organ dysfunction, shock and vasoplegia, lactate production, and mortality. Importantly, efficacy is maintained in some cases even when treatment is initiated hours after the onset of sepsis. The inhibition of nuclear factor–κB activation and subsequent expression of inducible nitric oxide synthase, adhesion molecules, and tumor necrosis factor–α by polyphenols is operative in ameliorating the sequelae of sepsis. Enhancement of the endogenous antioxidant capacity probably also contributes to the effectiveness of the polyphenols. Because several of the polyphenols reviewed in this article appear to be safe and to exert anti-inflammatory effects in humans, clinical trials assessing their efficacy in the critically ill are indicated. Whether delivered alone or in combination with nutritional formulas, polyphenols may help to prevent and treat sepsis.
Author: Sara A. Khan and Shubha Priyamvada and Neelam Farooq and Sheeba Khan and Md Wasim Khan and Ahad N.K. Yusufi
Gentamicin (GM) is an effective aminoglycoside antibiotic against severe infections but nephrotoxicity and oxidative damage limits its long term clinical use. Various strategies were attempted to ameliorate GM nephropathy but were not found suitable for clinical practice. Green tea (GT) polyphenols have shown strong chemopreventive and chemotherapeutic effects against various pathologies. We hypothesized that GT prevents GM nephrotoxicity by virtue of its antioxidative properties. A nephrotoxic dose of GM was co-administered to control and GT-fed male Wistar rats. Serum parameters and enzymes of oxidative stress, brush border membrane (BBM), and carbohydrate metabolism were analyzed. GM increased serum creatinine, cholesterol, blood urea nitrogen (BUN), lipid peroxidation (LPO) and suppressed superoxide dismutase (SOD) and catalase activities in renal tissues. Activity of hexokinase, lactate dehydrogenase increased whereas malate dehydrogenase decreased. Gluconeogenic enzymes and glucose-6-phosphate dehydrogenase were differentially altered in the cortex and medulla. However, GT given to GM rats reduced nephrotoxicity parameters, enhanced antioxidant defense and energy metabolism. The activity of BBM enzymes and transport of Pi declined by GM whereas GT enhanced BBM enzymes and Pi transport. In conclusion, green tea ameliorates GM elicited nephrotoxicity and oxidative damage by improving antioxidant defense, tissue integrity and energy metabolism.
Author: Sara A. Khan and Shubha Priyamvada and Wasim Khan and Sheeba Khan and Neelam Farooq and Ahad N.K. Yusufi
Cisplatin (CP) an anticancer drug is known to induce nephrotoxicity, which limits its long-term clinical use. Green tea (GT), consumed since ancient times is known for its numerous health benefits. It has been shown to improve kidney functions in animal models of acute renal failure. The present study was undertaken to see whether GT can prevent CP-induced nephrotoxic and other deleterious effects. A nephrotoxic dose of CP was co-administered to control and GT-fed male Wistar rats every fifth day for 25 days. The effect of GT was determined on CP-induced alterations in various serum parameters and on enzymes of carbohydrate metabolism, brush border membrane, and antioxidant defense system in renal cortex and medulla. CP nephrotoxicity was recorded by increased serum creatinine and blood urea nitrogen. CP increased the activities of lactate dehydrogenase and acid phosphatase whereas, the activities of malate dehydrogenase, glucose-6-phosphatase, superoxide dismutase, catalase, and 32Pi transport significantly decreased. GT consumption increased the activities of the enzymes of carbohydrate metabolism, brush border membrane, oxidative stress, and 32Pi transport. GT ameliorated CP-induced nephrotoxic and other deleterious effects due to its intrinsic biochemical/antioxidant properties.
Author: T. Malik and D.J. Haleem
Haloperidol (HAL) a conventional antipsychotic is known to induce oxidative stress-related anxiety. Parkinsonism and Tardive Dyskinesia (TD) in patients treated with drug. Antioxidative agents may suppress the neuroleptic induced anxiety and TD. The constituents of green tea have found antioxidative. In a view of antioxidative properties of green tea, the present study was designed to monitor a possible suppression of anxiety and Tardive Vacuous Chewing Movement (tVCM) by green tea in rat model of TD and anxiety. Associated changes of Dopamine (DA) and Serotonin (5-hydroxytryptamine; 5-HT) metabolism were also monitored in the dorsal (dStr) and ventral striatum (vStr). Rats on HAL for 8 weeks exhibited tVCMs and anxiety. Green tea Extract (GTE) alone as a sole source of water did not produce tVCMs and anxiety but HAL induced significant anxiety and tVCMs were 100% (two fold) greater than water treated group. The metabolism of DA as indicated by Homovanellic acid (HVA) concentration increased in the dStr of HAL plus GTE treated animals. HAL plus GTE treated group exhibited smaller increase of HVA. The mteabolism of 5-HT as indicated by 5-hydroxyindoleacetic acid (5-HIAA) concentration also increased in the dStr of HAL but not GTE treated animals. Groups of co-treated with HAL and GTE exhibited a large increase 5 HIAA in the dStr. The results suggested that interaction of HAL with some constituents of GTE may exacerbated HAL induced anxiety and TD by producing an imbalance of DA/5-HT control over anxiety and motor impairment.
“Do you want a vodka? No, a green tea please!” Epigallocatechin gallate and its possible role in oxidative stress and liver damage
Author: Lorenzo Leggio and Giovanni Addolorato
Author: Ka H. Chan and Siu P. Ho and Sze C. Yeung and Wallace H.L. So and C.H. Cho and Marcel W.L. Koo and Wah K. Lam and Mary S.M. Ip and Ricky Y.K. Man and Judith C.W. Mak
Background Epigallocatechin-3-gallate (EGCG), which has been shown to have potent antioxidant effect, comprises 80% of catechins in Chinese green tea. This study was to investigate whether cigarette smoke (CS) exposure would induce lung morphological changes and oxidative stress in the CS-exposed rat model, and whether Chinese green tea (Lung Chen tea with EGCG as its main active ingredient) consumption would alter oxidative stress in sera and lung leading to protection of CS-induced lung damage. Methods Sprague-Dawley rats were randomly divided into four groups, i.e. sham air (SA), 4% CS, 2% Lung Chen tea plus SA or 4% CS. Exposure to SA or 4% CS was performed for 1 h/day for 56 days in ventilated smoking chambers. Sera and lung tissues were collected 24 h after last CS exposure for histology and all biochemical assays. Results Airspace enlargement and goblet cell hyperplasia were observed after 56-day CS exposure alone, which were abolished in the presence of green tea consumption. Serum 8-isoprostane level was significantly elevated (p<0.01) as well as lung superoxide dismutase (SOD) and catalase activities in CS-exposed rats compared to SA-exposed rats (p<0.05), which returned to the levels of SA-exposed rats after Chinese green tea consumption. Conclusion These results indicate that increased levels of systemic oxidative stress after CS exposure play an important role in the induction of lung damage. Chinese green tea may have the ability to suppress CS-induced oxidative stress that leads to protection of lung injury.
Author: Feng Li and Juan Xu and Jing Zhou and Liyan Zhao and Jianchun Sheng and Guiju Sun and Qiuhui Hu
The anticlastogenic effect of micrometer powder of selenium-enriched green tea (MSTP) was evaluated by using a chromosomal aberration assay in mouse testicular cells. Animals fed with a Se-deficient diet were treated with MSTP, micrometer powder of regular green tea (MRTP), selenite, and MRTP + selenite for 30 days by an intragastric route, followed by treatment of mitomycin C (MMC) on day 19 through intraperitoneal injection (ip). Selenium status and antioxidant enzymes were measured. Results indicated that MSTP showed a significant capability to reduce the incidence of MMC-induced chromosomal aberrations in spermatocytes from 22.7% to 6.7%. This inhibitory was highest, for MSTP, at 73.1%, while it was only 38.4% for MRTP. After 30 days of a Se-deficient diet, mice, either with or without the MMC treatment, showed a lower selenium concentration in blood and liver as well as lower enzyme activity of the antioxidants, GPx and SOD. Supplementation with MSTP, selenite, or selenite + MRTP enhanced the activities of these antioxidant enzymes. This enhancement was accompanied with a concomitant elevation of selenium levels, which favored the synthesis of the seleno-enzyme GPx and protected the cells from the MMC-induced oxidative stress. Our results indicate that MSTP is both able to prevent the chromosomal aberrations induced by MMC in mouse spermatocytes and to enhance GPx and SOD activity in blood serum and liver.
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.
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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.”
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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.
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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.
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