Holistic Health Articles and Research Related to Herbal Medicines, Foods and Phytochemicals : Green Tea Epigallocatechin gallate (EGCG) Induced 11 Health Benefits, 6 Interactions and 4 Crucial Side Effects

Green tea containing highest amount of antioxidants than any drink or food with the same volume, is the leaves of Camellia sinensis, undergone minimal oxidation during processing and originated from China.

The leaves are precious drinks in traditional Chinese culture and used exceptional in socialization for more than 4000 thousand years.

Because of their health benefits, green tea is cultivated for commercial purposes all over the world.

Epigallocatechin, including catechins, is a phytochemical of Flavan-3-ols, in the group of Flavonoids (polyphenols), found abundantly in green tea, St John wort, black Tea, carob flour, Fuji apples, etc.

A. Medical Benefits

1. Anti-Breast Cancer Activities
In the testing the hypothesis that administration of epigallocatechin-3-gallate (EGCG), a polyphenol present in abundance in widely consumed tea, and its inhibition of cell proliferation, invasion, and angiogenesis in breast cancer, found that treatment with combination of radiotherapy and EGCG feeding for 2-8 weeks to in vitro cultures of highly-metastatic human MDA-MB-231 breast cancer cells resulted in the following significant changes: (1) suppression of cell proliferation and invasion; (2) arrest of cell cycles at the G0/G1 phase; (3) reduction of activation of MMP9/MMP2, expressions of Bcl-2/Bax, c-Met receptor, NF-κB, and the phosphorylation of Akt. MDA-MB-231 cells exposed to 5-10 µM EGCG also showed significant augmentation of the apoptosis inducing effects of γ-radiation, concomitant with reduced NF-κB protein level and AKT phosphorylation, according to "Anti-Cancer Activities of Tea Epigallocatechin-3-Gallate in Breast Cancer Patients under Radiotherapy" by Zhang G, Wang Y, Zhang Y, Wan X, Li J, Liu K, Wang F, Liu Q, Yang C, Yu P, Huang Y, Wang S, Jiang P, Qu Z, Luan J, Duan H, Zhang L, Hou A, Jin S, Hsieh TC (1)

2. Anti cancers
In the review and outline the wide range of mechanisms by which epigallocatechin gallate (ECGC) and other green and black tea polyphenols' inhibition of cancer cell found that EGCG reduced dihydrofolate reductase activity, which would affect nucleic acid and protein synthesis. It also acted as an aryl hydrocarbon receptor an-tagonist by directly binding the receptor's molecular chaperone, heat shock protein 90. In conclusion, green and black tea polyphenols act at numerous points regulating cancer cell growth, survival, and metastasis, including effects at the DNA, RNA, and protein levels, according to "Mechanisms of cancer prevention by green and black tea polyphenols" by Beltz LA, Bayer DK, Moss AL, Simet IM.(2)

3. Anti-atherosclerotic effects
In the localization and target sites of tea catechins underlying their biological activity including anti-atherosclerotic activity, found that ECg could suppress the gene expression of a scavenger receptor CD36, a key molecule for foam cell formation, in macrophage cells. These results, for the first time, showed the target site of a tea component ECg in the aorta and might provide a mechanism for the anti-atherosclerotic actions of the catechins, according to "(-)-Epicatechin gallate accumulates in foamy macrophages in human atherosclerotic aorta: implication in the anti-atherosclerotic actions of tea catechins" by Kawai Y, Tanaka H, Murota K, Naito M, Terao J.(3)

4. Inflammatory effects
In the determination of the up-regulated expressions of IL-8 or PGE(2) in Streptococci or PAMP-stimulated HDPF were inhibited by catechins, (-)-epicatechin gallate (ECG) and (-)-epigallocatechin gallate (EGCG). In TLR2 ligand-stimulated HDPF, found that catechins might be useful therapeutically as an anti-inflammatory modulator of dental pulpal inflammation, according to "Tea catechins reduce inflammatory reactions via mitogen-activated protein kinase pathways in toll-like receptor 2 ligand-stimulated dental pulp cells" by Hirao K, Yumoto H, Nakanishi T, Mukai K, Takahashi K, Takegawa D, Matsuo T.(4)

5. Cardiovascular diseases
In the identification of green tea catechins and its lowering the risk of cardiovascular diseases, found that green tea catechins, particularly (-)-epigallocatechin gallate, interfere with the emulsification, digestion, and micellar solubilization of lipids, critical steps involved in the intestinal absorption of dietary fat, cholesterol, and other lipids. Based on the observations, it is likely that green tea or its catechins lower the absorption and tissue accumulation of other lipophilic organic compounds, according to "Green tea as inhibitor of the intestinal absorption of lipids: potential mechanism for its lipid-lowering effect" by Koo SI, Noh SK.(5)

6. Antiviral activities
In the observation of Catechin derivatives including (-)-epicatechin gallate(ECG), (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC) and green tea extract (GTE) and theirs inhibition of the activities of cloned human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT), duck hepatitis B virus replication complexes reverse transcriptase (DHBV RCs RT), herpes simplex virus 1 DNA polymerase (HSV-1 DNAP) and cow thymus DNA polymerase alpha (CT DNAP alpha, found that GCG exerts a mixed inhibition with respect to external template inducer poly (rA).oligo (dT) 12-18 and a noncompetitive inhibition with respect to substrate dTTP for HIV-1 RT. Bovine serum albumin significantly reduced the inhibitory effects of catechin analogues and GTE on HIV-1 RT. In tissue culture GTE inhibited the cytopathic effect of coxsackie B3 virus, but did not inhibit the cytopathic effects of HSV-1, HSV-2, influenza A or influenza B viruses, according to "[The inhibitory effects of catechin derivatives on the activities of human immunodeficiency virus reverse transcriptase and DNA polymerases].[Article in Chinese]" by Tao P.(6)

7. Metabolic syndrome
In the investigation of Tea catechins, including the gallate esters of catechins, (-)-epicatechin gallate (ECG) and (-)-epigallocatechin gallate (EGCG). in reducing serum cholesterol concentrations and suppressing postprandial hypertriacylglycerolemia in experimental animals and humans, found that tea catechins and heat-treated tea catechins with the galloyl moiety improve lipid metabolism and contribute to the prevention of the metabolic syndrome, according to "Multifunctional effects of green tea catechins on prevention of the metabolic syndrome" by Ikeda I.(7)

8. Cognitive effects
in the examination of examined whether long-term administration of green tea catechins [Polyphenon E (PE): 63% of epigallocatechin-3-gallate, 11% of epicatechin, 6% of (-)-epigallocatechin and 6% of (-)-epicatechin-gallate] prevents cognitive impairment in an animal model of AD, rats infused with Abeta1-40 into the cerebral ventricle, found that rats with preadministered PE had higher ferric-reducing antioxidation power of plasma as compared with the Vehicle group. Our results suggest that long-term administration of green tea catechins provides effective prophylactic benefits against Abeta-induced cognitive impairment by increasing antioxidative defenses, according to "Green tea catechins prevent cognitive deficits caused by Abeta1-40 in rats" by Haque AM, Hashimoto M, Katakura M, Hara Y, Shido O.(8)

9. Cholesterol
In the examination of the influence of green tea extract, epicatechin (EC), epicatechin galate (ECG) as well as epigallocatechin galate (EGCG) on oxidative modifications of LDL of human blood serum, found that Catechins and green tea abilities to protect lipophilic antioxidant--alpha-tocopherol against oxidation have been also examined. The results reveal that peroxidation of LDL is markedly prevented by green tea extract and in a slightly weaker way by catechins (EGCG in particular), which is manifested by a decrease in concentration of conjugated dienes, lipid hydroperoxides, MDA, dityrosine and by an increase in tryptophan content, according to "The comparison of effect of catechins and green tea extract on oxidative modification of LDL in vitro" by Ostrowska J, Skrzydlewska E.(9)

10. Anti diabetes
In the observation of the effect of tea catechins (epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG) and epicatechin (EC)) on markers of oxidative stress (malondialdehyde (MDA), reduced glutathione (GSH) and membrane -SH group) in erythrocytes from type 2 diabetics, found that tea catechins protect erythrocytes from t-BHP-induced oxidative stress, the effect being more pronounced in diabetic erythrocytes. The relative effectiveness of individual catechins are in the order of EGCG>ECG>EGC>EC. 7. We hypothesise that a higher intake of catechin-rich food by diabetic patients may provide some protection against the development of long-term complications of diabetes, according to "Protective role of tea catechins against oxidation-induced damage of type 2 diabetic erythrocytes" by Rizvi SI, Zaid MA, Anis R, Mishra N.(10)

11. Antioxidants
In the evaluation of the effects of the main polyphenolic components extracted from green tea leaves, i.e. (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin gallate (EGCG) and gallic acid (GA), against free radical initiated peroxidation of human low density lipoprotein (LDL), found that The antioxidative action of the green tea polyphenols includes trapping the initiating and/or propagating peroxyl radicals with the activity sequence EC>EGCG>ECG>EGC>GA for the AAPH initiated peroxidation, and reducing the alpha-tocopheroxyl radical to regenerate alpha-tocopherol with the activity sequence of ECG>EC>EGCG>EGC>GA and ECG>EGCG>GA>EC>EGC for the AAPH-initiated and BP-photosensitized peroxidations respectively, according to "Antioxidative effects of green tea polyphenols on free radical initiated and photosensitized peroxidation of human low density lipoprotein" by Liu Z, Ma LP, Zhou B, Yang L, Liu ZL.(11).

B. Interactions
1. Oxidation
Risk of oxidation increased with air contact as humidity and temperature may enhanced EGCG degradation(12).

2. Optimized Extract Efficacy
In order to optimize the EGCG efficacy, intake the extract at least 30 min before breakfast and dinner(13).

3. Interaction with Hard Waters
Hard Waters containing elevated amounts of calcium, magnesium and other metals may affect the digestive absorption of EGCG(14).

4. Vitamin C
Intake EGCG with vitamin C may improve the extract bioavailability(15).

5. Omega 3 Fatty Acid
Intake EGCG with Omega-3 polyunsaturated fatty acids may enhance the extract bioavailability(16)

6. Piperine
Intake EGCG with Piperine may increase the efficacy of the extract through enhancing digestive absorption(13).

C. Side Effects
1. Anxiety
Intake of EGG may increased risk of anxiety, therefore people who are taking the anxiolytic medicine should avoid to inject EGCG(17).

2. Hypoglycemic Effect
Intake of EGCG may lower blood sugar, therefore people with low blood glucose should avoid to drink green tea and intake of the extract(18).

3. Anemia
EGCG is an iron inhibitor, therefore people with iron deficiency anemia should avoid intake of EGCG(19).

4. Liver and Kidney Toxicity
Over dose of EGCG may induce toxicity to both liver and kidney(20)

Natural Medicine for Fatty Liver And Obesity Reversal - The Revolutionary Findings To Achieve Optimal Health And Loose Weight

Ovarian Cysts And PCOS Elimination
Holistic System In Existence That Will Show You How To
Permanently Eliminate All Types of Ovarian Cysts Within 2 Months

Back to Kyle J. Norton Home page http://kylejnorton.blogspot.ca

Sources

(1) http://www.ncbi.nlm.nih.gov/pubmed/22280355