Protective Effect Of Green Tea Research Articles

Protective effects of green tea (Camellia sinensis) extract against cypermethrin-induced neurotoxicity in rainbow trout (Oncorhynchus mykiss) brain tissues

Protective effects of green tea (Camellia sinensis) extract against cypermethrin-induced neurotoxicity in rainbow trout (Oncorhynchus mykiss) brain tissues

Protective effects of green tea on blood and liver of rats fed with high fructose diet

Abstract This study was designed to investigate the effects of green tea on lipid profile, liver tissue damage, and oxidative stress in rats fed a diet including high fructose. Sprague-Dawley rats were randomly divided into four groups: Control (C), Fructose (F), Green Tea (GT), and F+GT. F and F+GT groups were given 20% fructose in the drinking water for eight weeks. Green tea (2 mg kg−1) was administrated to GT and F+GT groups by oral gavage for eight weeks. Biochemical parameters in serum and oxidative stress markers in the liver were analysed. The liver sections were stained with haematoxylin-eosin. As of the 3rd week of the experiment, the body weight of rats in the F group showed a statistically significant increase in comparison with the F+GT group. The serum glucose and triglyceride levels of the F+GT group significantly decreased when compared with the F group. The fructose-induced degenerative changes in the liver were reduced with green tea. Green tea may serve a protective role against hyperlipidaemia and liver injury in rats fed a high fructose diet.

Protective effects of epigallocatechin-3-o-gallate combined with organic selenium against transforming growth factor-beta 1-induced fibrosis in LX-2 cells.

In this study, we investigated the protective effects and possible mechanism of epigallocatechin-3-o-gallate (EGCG) combined with organic selenium in transforming growth factor (TGF)-β1-activated LX-2 cells. After 12 h of starvation, LX-2 cells were treated with 10ng/ml of recombinant TGF-β1 and different concentrations of EGCG, L-selenomethionine (L-SeMet), or L-selenomethylcysteine (L-SeMC) for 24 h. We found that 100 and 200 μM EGCG combined with 1 mM L-SeMet or L-SeMC showed a synergistic effect in decreasing the survival rate of activated LX-2 cells. In addition, the combination of 100 mM EGCG and 1 mM L-SeMet or L-SeMC promoted the apoptosis of activated LX-2 cells. Compared with the EGCG treatment group, the combination intervention group had significantly suppressed levels of hepatic stellate cell activation markers including alpha-smooth muscle actin, collagen type I alpha 1, collagen type III alpha 1, 5-hydroxytryptophan (5-HT), and 5-HT receptors 2A and 2B. Moreover, interleukin-10 levels were decreased, while TGF-β1 levels were increased after TGF-β1 activation in LX-2 culture medium, whereas the combin1ation intervention reversed this phenomenon. The combination treatment had a more pronounced effect than any single treatment at the same dose. These results demonstrated that the combination of EGCG and organic selenium synergistically improves the TGF-β1-induced fibrosis of LX-2 cells to some extent by promoting apoptosis and inhibiting cell activation. PRACTICAL APPLICATIONS: Here, we found that the effects of epigallocatechin-3-o-gallate (EGCG) + L-selenomethionine or L-selenomethylcysteine were more pronounced than those of EGCG alone. Future studies should investigate the protective effects of green tea and selenium-enriched green tea against hepatic fibrosis and explore the differences in their molecular mechanisms. The results of this study will be helpful for the development and utilization of selenium-enriched tea for food processing and health supplement production.

Protective effect of green tea in methotrexate-induced nephrotoxicity

Protective effect of green tea in methotrexate-induced nephrotoxicity

Protective effect of green tea and epigallocatechin-3-gallate in a LPS-induced systemic inflammation model

Inflammation causes severe dysregulation of organ functions, via the development of oxidative stress and inflammation damage. Polyphenol compounds found in green tea (GTE), including the most important component epigallocatechin-3-gallate (EGCG), have a great therapeutic potential. Here, protective properties of GTE and EGCG against lipopolysaccharide (LPS)-induced inflammation are explored. To this end, the effects of GTE and EGCG were studied on LPS challenged macrophages. Mice received GTE (250 mg/kg/d/p.o) or EGCG (25 mg/kg/d/i.p.) for 7 d, before the inflammation shock was provoked with a single intraperitoneal injection of LPS. The frequencies of lymphocytes CD4+, CD8+, NK1-1+ and CD4+CD25highFOXP3+ (Treg), macrophages CD11b+F480+, monocytes CD11b+Ly6Clow/high, neutrophils CD11b+Ly6G+, MDSCs CD11b+Gr-1high, M2/N2-like phenotype CD206+ and M1-like phenotype CD86+ in spleen, bone marrow and peripheral blood were determined. In vitro studies revealed that GTE and EGCG significantly attenuated LPS-induced CD80 expression and increased the CD163 expression, showing a potential to reduce the macrophage inflammatory phenotype. In vivo, GTE and EGCG inhibited the inflammation, mainly by reducing M1-macrophages and increasing Treg cells in the bone marrow. In addition, GTE and EGCG increase M2-macrophages, N2-neutrophils and Tregs in the spleen and blood and block the migration of monocytes from the bone marrow to the peripheral blood. These findings indicate that EGCG and GTE prevent LPS-induced inflammatory damage contributing to restoring the immune system homeostasis.

The Potential Role of Green Tea and its Main Constituent (Epigallocatechin -3-Gallate) in Pain Relief: A Mechanistic Review.

Medicinal plants and dietary supplements may provide an effective and safe treatment for pain relief. Green tea is one of the most common beverages with many several pharmacological activities. The results of various studies have indicated that green tea possesses antinociceptive effects. Many of the protective effects of green tea in terms of pain relief are attributed to its antioxidant and anti-inflammatory properties. Epigallocatechin -3-gallate (EGCG), as one of the major phytochemical components in green tea, is effective in the management of pain through suppression of inflammation and oxidative stress. We have reviewed the effects of green tea on pain and also discussed mechanisms involved in pain relief. This review suggests that green tea can be a safe and often effective treatment for pain.

Green Tea Suppresses Amyloid β Levels and Alleviates Cognitive Impairment by Inhibiting APP Cleavage and Preventing Neurotoxicity in 5XFAD Mice.

The consumption of green tea is considered to be associated with a lower incidence of neurodegenerative diseases. In the present study, it is investigated the role of amyloid precursor protein cleavage, glial cell activation, neuroinflammation, and synaptic alterations in the protective effects of green tea against the amyloid β (Aβ) accumulation and cognitive impairment. 5XFAD mice are treated with green tea extract (GTE) for 8 or 16 weeks. Barnes maze and Y maze testing demonstrated that spatial learning and memory ability are markedly improved by GTE treatment. Immunofluorescence staining, ELISA, and western blot showed GTE significantly alleviate the formation of Aβ and reduce the levels of sAPPβ and C99, as well as sAPPα and C83. Meanwhile, GTE suppressed GFAP and Iba1 levels in the glial cells, increased PSD95 and synaptophysin levels in synaptic cells. Further, the IL-1β level is decreased, RNA sequencing reveals the genes annotated in response to stimulus and immune response are regulated. Our findings indicate GTE suppresses Aβ levels and alleviate cognitive impairment in 5XFAD mice. These beneficial effects are accompanied by inhibition of APP cleavage pathways, suppression of glial cell activation and pro-inflammatory responses, and a reduction of synapse loss.

Protective Effect of Commercial Green Tea on Ibuprofen Induced Changes in Renal Function Tests of Adult Rats

Background: Nephrotoxicity of ibuprofen is a growing international public health problem in the wake of excessive use of the drug for the treatment of a broad spectrum of diseases in both adults and pediatric patients. Objectives: To present an overview of the protective effect of the green tea on ibuprofen-induced changes in the biochemical markers of the adult rat kidneys. Methods: It is an experimental study conducted in the department of Anatomy, Army Medical College Rawalpindi. The investigation was led on 30 male and non-pregnant female Sprague Dawley rodents of 9-11 weeks old enough and going in weight from 200-330 gm. The animals were divided into three groups consisting of 10 animals each; group A served as control, each animal in group B was given ibuprofen at a dose of 120 mg/kg/day and each animal in group C was given both green tea at a dose of 1ml/100g/day and Ibuprofen 120mg/kg body weight for a period of 9 weeks. Ibuprofen manufactured by Abbot Laboratories (Pvt.) Limited was utilized. Green tea was obtained from local market. Data was collected at the end of experimental period and was analyzed using SPSS version 22. One Way ANOVA was exerted, afterwards by post-hoc Tukey test to find out intergroup differences for quantitative variables. The results were depicted as mean ± standard deviation (mean ± SD). A p value < 0.05 was believed significant. Results: Green tea administration had a significantly favorable effect on serum urea (mg/dl) (Group A=21.9 ± 2.8, Group B=93.2 ± 3.9, Group C=36.4± 3.0; p<0.001) and serum creatinine (mg/dl) (Group A=0.9 ± 0.22, Group B=2.4± 0.52, Group C=0.97 ± 0.3; p<0.001). Conclusions: Green tea had ameliorative effects on the ibuprofen-induced changes in the biochemical markers of the adult rat kidneys.

Green tea consumption and risk for esophageal cancer: A systematic review and dose-response meta-analysis

ObjectiveControversial results of the association between green tea consumption and risk for esophageal cancer (EC) were reported by previous meta-analysis. Thus, the aim of this study was to quantitatively investigate the association. MethodsThe Cochrane Library, PubMed, and EMBASE databases were searched for relevant studies. We used a “one-stage approach” with a restricted cubic spline model to summarize the dose-specific relationships between green tea and risk for EC. Odds ratios (ORs) were used to measure the effects. Fourteen studies were included with a total of 5057 ECs among 493 332 participants. ResultsIn the dose–response analysis, the summary OR for a 1 cup/d increase in green tea was 1.00 (95% confidence interval [CI], 0.95–1.04; I2 = 77%). No nonlinearity association was observed between tea consumption and risk for EC (P = 0.71 for nonlinearity). In the subgroup of sex, the summary OR for a 1 cup/d increase in green tea was 1.03 (95% CI, 0.95–1.11, I2 = 67%) for men and 0.79 (95% CI, 0.68–0.91; I2 = 0%) for women. ConclusionContrary to previous studies, based on current evidence, the present dose–response study suggested no association between green tea and risk for EC. However, there might be a protective effect of green tea in women. Notably, our conclusion might be influenced by limited studies and potential bias, such as dose of green tea assessment and select bias of case–control studies. Further larger number, prospective, and well-designed larger-scale studies are needed to provide more precise evidence, especially in women and more regions (United States and Europe).

Green Tea (Camellia sinensis) Ameliorate Non-alcoholic Fatty Liver Disease Induced by Highly Active Antiretroviral Therapy

Background: Highly Active Antiretroviral Therapy (HAART) has significantly enhanced the life expectancy of HIV-infected patients. However, utilization of HAART has been identified with adverse events including nonalcoholic fatty liver disease (NAFLD). Objectives: The Objective of this experiment was to explore the conceivable protective effect of green tea (Camellia sinensis) hydro-methonolic extract (GTE) on highly active antiretroviral therapy-induced NAFLD in albino Wistar rats. Methods: Thirty adult rats of comparative weights were chosen and divided into 5 groups of six rats each. Group-1 was a control group, Group II was given HAART and served as negative control, Groups III, IV and V were given HAART and 100, 200 and 400 mg/kg of GTE, respectively for sixty days. At the end of experiment day, the rats were fasted overnight sacrificed by cervical dislocation and blood was taken via cardiac puncture. Serum was separated and liver function test was assessed. Liver were excised from the rats, histopathological studies and lipid profiles were also investigated. Results: Elevated levels of serum TGL, total cholesterol, ALT, AST and liver TGL, TBARS and decreased levels of TAC was seen in HARRT treated rats. The amelioration potential of GTE was observed in a dose-dependent manner, the highest dose 400mg/kg more potently ameliorated HAART affected parameters near to the normal control. Conclusion: This consequence of HAART induced NAFLD may be due to oxidative stress by mitochondrial ROS that leads to increased hepatocellular oxidative damage. This may progress to hepatic inflammation and the development of NAFLD. The effect of GTE against NAFLD and oxidative stress might be due to its antioxidant activity and scavenging of reactive oxygen species induced by HAART.

The protective effect of green tea on diabetes-induced hepato-renal pathological changes: a histological and biochemical study

We investigated the protective effect of green tea on diabetic hepato-renal complications. Thirty male Wistar rats were randomly divided into five equal groups: normal control, diabetic control, glibenclamide-treated, green tea-treated, and combined therapy-treated groups; ethical approval number “BERC-014-01-20.” After eight weeks, animals were sacrificed by CO2 euthanasia method, liver and kidney tissues were processed and stained for pathological changes, and blood samples were collected for biochemical analysis. Diabetic rats showed multiple hepato-renal morphological and apoptotic changes associated with significantly increased some biochemical parameters, while serum albumin and HDL decreased significantly compared to normal control (p < .05). Monotherapy can induce significant improvements in pathological and biochemical changes but has not been able to achieve normal patterns. In conclusion, green tea alone has a poor hypoglycaemic effect but can reduce diabetic complications, whereas glibenclamide cannot prevent diabetic complications. The addition of green tea to oral hypoglycaemic therapy has shown a potent synergistic effect.

Study on the protective effect of green tea against bisphenol A- induced amyloid aggregation in the brain of male albino rats.

&nbsp;&nbsp;&nbsp; Bisphenol A (BPA) has been used in the plastic industry and widely distributed in the environment. Green tea extract has been known for its antioxidant activity. This study was designed to investigate the protective efficacy of green tea against brain amyloid aggregation which induced by BPA. Twenty male albino rats were exposed to BPA (500 mg/kg); green tea ethanolic extracts in two dose levels 150 and 300 mg/kg respectively plus BPA. After 60 days, malondialdehyde (MDA), superoxide dismutase (SOD)&nbsp; in the brain were measured besides body and brain weights. BPA exposed groups showed a significant reduction (P&lt;0.05) in the final body weight, with a non-significant reduction in absolute brain weight. BPA was also increased oxidative stress in the brain of the treated rats besides histological changes with amyloid deposition in the brain detected by congo red staining technique. Treatment with green tea ethanol extracts were protected animal brains against adverse effects caused by BPA and reduced oxidative stress in a dose-dependent manner. that may be related to enriched ingredients that&nbsp; have been found in the extract.

Green tea consumption and risk of hematologic neoplasms: the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study).

Experimental studies suggested that green tea may have an anticancer effect on hematologic neoplasms. However, few prospective studies have been conducted. A total of 65,042 individuals aged 40-79years participated in this study and completed a self-administered questionnaire about their lifestyle and medical history at baseline (1988-1990). Of these, 52,462 individuals living in 24 communities with information on incident hematologic neoplasms available in the cancer registry, who did not have a history of cancer and provided valid information on frequency of green tea consumption, were followed through 2009. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of hematologic neoplasms according to green tea consumption were analyzed. The incidence of hematologic neoplasms during a median follow-up of 13.3years was 323. Compared with the never-drinkers of green tea, the multivariate HRs and 95% CIs for total hematologic neoplasms in green tea drinkers of ≤ 2 cups/day, 3-4 cups/day, and ≥ 5 cups/day were 0.65 (0.42-1.00), 0.73 (0.47-1.13), and 0.63 (0.42-0.96), respectively. The association was more prominent for acute myeloid leukemias and follicular lymphomas. The present cohort study suggests a protective effect of green tea against hematologic neoplasms, especially acute myeloid leukemias.

The effect of green tea consumption on the expression of antioxidant‐ and inflammation‐related genes induced by nicotine

The aim of this study is to investigate the protective effect of green tea (GT) against the toxicity of nicotine. BALB/c mice were divided into four groups. Group I received food and water intake ad libidium, Group II received GT solution at a dose of 1ml/kg body weight orally twice a day via gastric gavage, Group III was injected intraperitoneally with nicotine (2.5mg/kg) once per day for 4weeks, and Group IV received both nicotine and GT; GT was introduced using gastric gavage 1hr before and 1hr after the nicotine injection. The administration of nicotine altered the cellular antioxidant defense system by inducing inflammation and damage in the tissues of liver, lungs, and kidneys. In addition, nicotine treatment significantly enhanced the expression antioxidant- and inflammation-related genes. There were significant improvements when the nicotine-exposed mice treated with GT. PRACTICAL APPLICATIONS: In this study, it is revealed that the administration of nicotine altered the cellular antioxidant defense system by inducing inflammation manifested by the infiltration of inflammatory cells and damage seen in liver, lungs, and kidneys. GT contributed to the reduction of toxicity of nicotine, probably mediated by free radicals, through downregulation of nicotine-induced upregulated antioxidant- and inflammation-related genes. Never the less, further in depth investigation on characterization of the active constituents of GT responsible for their effect seen here and the mechanism that contributes to the effects seen in this reports is highly demanded. Furthermore, GT extract could be considered as a dietary supplement for the reduction of nicotine toxicity among cigarette smoker.

Protective Effect of Green Tea Against Poisoning with Malathion in Adult Rats

Protective Effect of Green Tea Against Poisoning with Malathion in Adult Rats

Anti-fibrotic effect of black tea (Camellia sinensis) extract in experimental pulmonary fibrosis.

There is no effective therapy exists for Idiopathic pulmonary fibrosis (IPF) till now. Few studies have been done on protective effects of green tea in pulmonary fibrosis but there is no single report on black tea extract (BTE) in pulmonary fibrosis so far. This study aims to investigate the anti-fibrotic effect of BTE against experimental pulmonary fibrosis. Four groups of animals were selected for this study. Group 1: control group mice. Group 2: mice exposed to bleomycin for 21 days, Group 3 and Group 4: bleomycin exposed mice treated with 25 mg BTE/kg b.w./day, p.o and 50 mg BTE/kg b.w./day, p.o. respectively for 21 days. Bleomycin exposed mice showed increased collagen deposition and wet/dry weight ratio, which were attenuated upon 50 mg BTE/kg b.w. treatment. The increased level of histopathological parameters in bleomycin-induced mice was significantly decreased after 50 mg BTE/kg b.w. treatment. Furthermore, 50 mg BTE/kg b.w. administration also decreased the expression of α-SMA in bleomycin-induced mice. This treatment with 50 mg BTE/kg b.w. also down regulated the expression of TGF-β and up regulated IFN-γ expression in experimental pulmonary fibrosis. The results of the present study put-forward BTE as a potential anti-fibrotic agent due to its attenuating effect on potential fibrotic markers.

Protective effect of green tea on tunica adventitia and endothelial changes resulting from depot medroxy progesterone acetate.

ObjectiveThis study aimed to analyse the effects of green tea in inhibiting uterine atrophy and vascular changes due to the use of depot medroxy progesterone acetate (DMPA).MethodsTwenty-five female Wistar rats aged one to two months were randomly assigned to five treatment groups: control group, DMPA-induced group, and DMPA-induced group orally treated with green tea extract (at 10.8 mg/day, 21.6 mg/day, or 43.2 mg/day). Histologic analysis of uterine and vascular tissues was performed with haematoxylin-eosin staining.ResultsDMPA decreased the thickness of endometrium and tunica adventitia, as well as significantly decreased endothelial cell count (p < 0.05). DMPA-induced decreases in the thickness of tunica adventitia and endothelial cell count could be significantly inhibited by green tea extract (p < 0.05).ConclusionThis study concluded that DMPA triggered the depletion of uterine endometrium and vascular tunica adventitia and decreased endothelial cell count. Green tea extract at the highest dose normalized tunica adventitia and endothelial changes to the basal value.

Diallyl disulfide potentiates anti-obesity effect of green tea in high-fat/high-sucrose diet-induced obesity

Obesity is a major problem in developed countries and a burden on social health care systems. Several epidemiological studies showed the protective effects of green tea against obesity-related diseases. Cyclic guanosine monophosphate (cGMP) acts as a mediator for the physiological effects of (−)-epigallocatechin-3-O-gallate, the major constituent of green tea. Here, we showed that the level of phosphodiesterase 5, a negative regulator of cGMP, was up-regulated in adipose tissues of high-fat/high-sucrose (HF/HS) diet-fed mice and that this up-regulation was ameliorated by diallyl disulfide (DADS), the major organosulfur in garlic. A green tea extract (GT) and DADS in combination attenuated HF/HS diet-induced adipose increase and triglyceride accumulation in the liver. In these mechanisms, the combination regimen suppressed the HF/HS diet-induced up-regulation of fatty acid synthesis-related enzymes including sterol regulatory element-binding protein-1 (SREBP-1), fatty acid synthase, and stearoyl-CoA desaturase-1. Moreover, this combination diet up-regulated thermogenesis-related genes including peroxisome proliferator-activated receptor (PPAR) gamma coactivator 1 alpha and uncoupling proteins in both white and brown adipose tissues. In conclusion, we identified DADS as an enhancer of the anti-obesity effect of GT accompanied by the suppression of SREBP-1 and activation of PPAR axis. The combination diet is a novel and easily applicable approach against obesity-related diseases.

Green tea extract attenuates non alcoholic fatty liver disease by decreasing hyperlipidemia and enhancing Superoxide dismutase activity in cholesterol-fed rats

BACKGROUND/AIM: Health benefits of green tea for a wide variety of ailments, including the cancer, heart disease, and liver disease, were reported. It is believed to have beneficial effects in the prevention and treatment of many diseases, one of which is non-alcoholic fatty liver disease (NAFLD). This study inspects the protective effect of green tea against atherosclerosis and NAFLD in comparative approach between curative and preventive models. MATERIALS AND METHODS: Twenty four of Wistar rats were studied for 150 days. After 15 days of adaptation period, rats were divided into four groups including normal Group (NG), control Hypercholesterolemic diet Group (CHDG), preventive Group (PG) and curative Group (CG) that followed respectively the following regimens: 1 mL/kg of sunflower oil for 150 days, 1 mL/kg of cholesterol solution prepared at 1.5% (w/v) in sunflower oil span 150 days, 1 ml/kg of cholesterol solution at 1.5% (w/v) in sunflower oil with 3 mL/kg GTLE for 60 days and 1 mL/kg of cholesterol solution at 1.5% (w/v) in sunflower oil for 30 days followed by 3 mL/kg of GTLE for 30 days. These both PG and CG groups were ingested with cholesterol 1.5% (w/v) during remaining period. RESULTS: The results showed significant increase, except for NG, during the 30 first days (p≤0.001) in lipid serum profiles including Total Cholesterol (TC), Triacylglycerol (TG) and Low-Density Lipoprotein cholesterol (LDL-c). However, the High-Density Lipoprotein cholesterol (HDL-c) profile decreased during the treatment (p≤0.001). The ingestion of GTLE in treated groups (CG and PG) declined significantly (p≤0.001) in blood lipid concentrations (TC: 67%, TG: 23%, LDL-c: 81.12%) except for the HDL-c that increased up to 15%. The Atherogenic Index (AI) also decreased significantly (p≤0.001) up to 48%, in CG and PG. PG and NG marked same SOD activity values (130.91±7.66 versus 141.31±8.21 U/mL), while CG showed the lowest level. Liver sections were well protected in protective model than curative one.

Gender differences in the protective effects of green tea against amnestic mild cognitive impairment in the elderly Han population.

BackgroundGender differences may contribute to variances in the potential protective effects of tea against cognitive impairment in the elderly.ObjectiveTo examine the association between different types of tea consumption and the risk of amnestic mild cognitive impairment (aMCI) along gender lines.MethodsA cross-sectional study was conducted with reference to 20 communities in China. The sample population included elderly participants aged 60 years or older. A standardized questionnaire was used to collect each participant’s general demographic information. Trained psychologists administrated the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to assess participants’ cognitive function. An attending psychiatrist evaluated each participant’s cognitive function. Finally, data from 2,131 participants were analyzed to assess the association.ResultsWith regard to male participants, the percentage of green tea consumption was higher in the normal control group than in the aMCI group (X2=4.64, P=0.031). Logistic regression analysis showed that green tea consumption reduced the risk of aMCI in male participants (OR=0.657, P=0.019), and this finding was highly significant in males aged under 70 years (OR=0.376, P=0.002). Regarding female participants across every age group, the results indicated that tea consumption failed to significantly decrease the risk of aMCI (P>0.05). Unlike green tea, black tea and oolong tea were not correlated with a reduced risk of aMCI in terms of gender or age group. Multiple linear regression analysis also revealed that age, years of education, and green tea consumption (B=0.996, P=0.000) were associated with MoCA and MMSE scores, though only in male participants.ConclusionGreen tea consumption showed a protective effect against aMCI in males but not in females, particularly in males aged <70 years. However, black tea and oolong tea failed to show any protective effect in either males or females.