    |
EGCG Research UpdatesEGCG News: Can EGCG Affect Morphine Dependence? Researchers have tested EGCG from green tea in an animal model of morphine dependence. When the morphine dependent animals are given naloxone, they show physical signs of withdrawal, including tremors, shaking, urination, teeth chattering, and rearing. When they were given EGCG from green tea prior to naloxone-stimulated morphine withdrawal, all the physical withdrawal symptoms were inhibited in a dose-dependent manner. As EGCG was increased, the withdrawal symptoms decreased. Also, EGCG reduced some of the neurological changes created by morphine intake. Specifically, EGCG inhibited the morphine-induced increase in cAMP levels in the locus coeruleus as well as signaling of the dopamine D2 receptor. Researchers believe this preliminary study suggests that EGCG from green tea has strong pharmacological action against morphine dependence and withdrawal symptoms (Oh KW, Effects of (-)-epigallocatechin gallate on the development of morphine-induced physical dependence, Archives of Pharmacal Research, September 2007). Many studies would be needed to determine if EGCG would also inhibit human morphine dependence or withdrawal symptoms. EGCG News: Green Tea And Atherosclerosis Atherosclerosis is the damage to blood vessels associated with high cholesterol. It can lead to arteriosclerosis and is a risk factor for heart attacks and strokes. A new study has found that ECG (epicatechin gallate), a polyphenol catechin in green tea, shows anti-atherosclerotic activity by targeting foamy macrophages directly in the atherosclerotic lesion damage. Foamy macrophage cells are an important part of deeper lesions. Preliminary cell studies showed significant accumulation of ECG in the foamy macrophage cells of human atherosclerotic lesions and found that ECG could suppress part of the DNA gene expression that leads to the formation of foamy macrophage cells (Kawai Y, (-)-Epicatechin gallate accumulates in foamy macrophages in human atherosclerotic aorta: Implication in the anti-atherosclerotic actions of tea catechins, Biochemical and Biophysical Research Communications, August 2008). ECG is one of several antioxidant catechins found primarily in green tea, each one with different functions. EGCG is the most powerful, and most studied green tea antioxidant. EGCG Research: Green Tea And Alcohol-damaged Liver Excess alcohol not only damages the liver, but can be lethal. While there are many studies showing that green tea can help protect the liver from damage, all mechanisms have not been clearly identified yet. A preliminary green tea research study using alcohol-damaged liver cells found that green tea reduced liver cell damage as measured by gamma-glutamyl transferase (GGT). Using HepG2 cells, researchers exposed the cells to a lethal amount of ethanol alcohol, and tracked GGT. GGT is used clinically as a measure of alcohol toxicity. They found that EGCG (epigallocatechin gallate), the primary antioxidant polyphenol from green tea, could effectively reduce GGT and prevent liver cell death. There was no protection from the caffeine or theanine in the tea. But EGCG did not reduce the intracellular gluthathione loss caused by ethanol alcohol. Researchers suggest that EGCG may provide a new strategy to be included with other GGT inhibitors for reducing liver damage from ethanol (Lee SI, Effect of green tea and (-)-epigallocatechin gallate on ethanol-induced toxicity in HepG2 cells, Phytotherapy Research March 2008). EGCG Research: EGCG For Old Philosophers? Every culture has treasured the gathered wisdom of their elders. We all mourned the loss when their brains become too damaged by age to function. And we ask how much more could wise people have contributed if they were functional longer. So we look for ways to keep this wisdom alive. One way is to work with preventing age-related damage to the brain. The brain can be damaged from free radicals because of its high metabolic needs and fatty acid structures. Thus a great deal of research has concentrated on the usefulness of antioxidants in protecting brain function over a lifetime. Researchers have recently tested EGCG (epigallocatechin gallate), the primary polyphenol flavonoid catechin antioxidant in green tea in an animal study of aging brains. For 30 days, oral intake of EGCG was compared with placebo saline. Researchers found that EGCG improved the following enzymatic antioxidants in the brain:
and the following non-enzymatic antioxidants:
EGCG also reduced free radical damage as shown in lowering malondialdehyde and protein carbonyl levels in the brain (Srividhya R, Attenuation of senescence-induced oxidative exacerbations in aged rat brain by (-)-epigallocatechin-3-gallate, International Journal of Developmental Neuroscience, December 2007). This study is preliminary and more work is needed to track functional benefits for the brain from EGCG from green tea. But a wise person once said that a journey of a thousand miles begins with one step. Perhaps it can also begin with one cup of green tea. EGCG Research: Nerve Degeneration Diseases There is growing research that oxidative stress is involved in the damage that occurs with neurodegenerative diseases. Part of that damage comes from free radicals and abnormal metal metabolism. A great deal of research has focused on solving these problems separately. Now researchers are studying natural polyphenols like EGCG from green tea because these chemicals can show broad spectrum benefits that include both antioxidant activity against free radicals and normalization of metal metabolism. In a preliminary EGCG research cell study, researchers have identified more genes and proteins that can be used as biomarkers to study the unique metabolic benefits of EGCG (Weinreb O, The application of proteomics for studying the neurorescue activity of the polyphenol (-)-epigallocatechin-3-gallate, Archives of Biochemistry & Biophysics, January 2008). These new biomarkers include:
EGCG (epigallocatechin gallate) is the primary polyphenol flavonoid catechin in green tea. EGCG Research: Glaucoma and EGCG Research Many laboratory studies have shown that green tea and EGCG can protect the retina and eye from some of the damage from free radical oxidation, glutamate toxicity, and post-ischemia loss of blood supply. Now a new animal study shows that EGCG from green tea in the drinking water provides protection from glaucoma. EGCG was given to half the animals for three days before administering increased intraocular pressure, and for five days afterwards. Damage parameters included localization of Thy-1 and choline acetyltransferase, electroretinogram amplitudes, proteins, mRNAs, and capsase activation. The results showed that drinking EGCG from green tea statistically reduced the damage in the animal glaucoma model (Zhang B, Brain Research, 2007). Researchers state that the use of EGCG from green tea is supported in the treatment of glaucoma for its safe profile, broad spectrum nerve protection, and reduction of damage to the eye from blood loss and other damaging risk factors. This research is still preliminary and you should consult with your health care provider for glaucoma treatment plans. EGCG Research: Muscular Dystrophy and EGCG research Duchenne/Becker Muscular Dystrophy (DBMD or DMD), is an inherited genetic condition causing muscles to deteriorate. It occurs in approximately 500 newborn boys in the United States every year. It is extremely rare for a girl to have muscular dystrophy, although women can carry the gene. The boys are usually diagnosed between the age of 3 and 6 years old, and by age 12 are usually unable to walk. It is almost always fatal in the teenage years or by the early 20's. There is currently no cure for muscular dystrophy, but steroids have been used to slow the muscular degeneration (CDC). Now a new study may open doors for more research on muscular dystrophy. Using an animal model of muscular dystrophy, researchers injected EGCG, the primary antioxidant catechin in green tea, under the skin of the backs of mice. This was done 4 times a week for 8 weeks. Compared to controls, the EGCG injections lowered the serum creatine kinase levels to normal. Lipofuscin granules in the muscles were reduced by 50%. Lipofuscin, also called liver spots when found on the skin, is a fatty pigment considered a sign of early aging. The EGCG research mice also had almost double the amount of normal muscle tissue, with a substantial reduction in damaged muscle and connective tissue. The strength of the muscles also increased to almost normal (Nakae Y, Histochemistry and Cell Biology, 2008). This research is considered very preliminary and further studies are needed to know if EGCG benefits would be long term, or would be useful for people with muscular dystrophy. EGCG Research: Arthritis and EGCG research Recent work with EGCG, the primary polyphenol antioxidant of green tea has shown remarkable protection against arthritis. Using fibroblast cells from the damaged joints of rheumatoid arthritis patients, researchers found that exposure to EGCG from green tea blocks chemicals that can cause bone damage. At higher doses, EGCG blocked production from the following inflammatory molecules involved in rheumatoid arthritic disease: interleukin-1beta (IL-1beta)-induced production of RANTES (CCL5), epithelial neutrophil-activating peptide 78 (ENA-78/CXCL5), growth-regulated oncogene alpha (GROalpha/CXCL1), and IL-1beta-induced MMP-2 activity. It reduced monocyte chemo-attractant protein 1 (MCP-1/CCL2) by 48%. Lower doses only reduced these chemicals. EGCG was nontoxic to the living fibroblast cells even at higher doses (Ahmed S, Arthritis Rheum, 2006). Other green tea studies have found significant prevention of arthritis in animals. Cell studies like the above are considered preliminary. The CDC, 2003 report says rheumatoid arthritis and osteoarthritis affect 46 million (21.6% of adults) in the United States alone. As baby boomers age, this number may double. The annual cost of arthritis is $128 billion for the United States (direct plus indirect costs). Some tea researchers relate their experimental design to people drinking about four 8-ounce cups of green tea throughout the day. Four cups of green tea daily costs less than $10 a month in the United States. Tea News: Protection Against Heart Attack Damage A new study from India tested EGCG, the primary antioxidant polyphenol from green tea, in an animal model of heart attacks. Without EGCG, animals after a heart attack showed significant increases in levels of lipid peroxidation products, levels of thiobarbituric acid reactive substances, and uric acid. At the same time, there was a significant decrease in the antioxidant activities of superoxidide dismutase, catalase, glutathione peroxidase, and other glutathione compounds in the heart as well as significant decreases in vitamin C and E. When test animals were given EGCG daily for 21 days prior to the induced heart attack, the opposite was seen. There was a significant decrease in lipid peroxidation compounds and significant protection of antioxidants. The greatest protection was with the larger daily doses of 30mg/kg of EGCG compared to lower doses of 10mg/kg or 20mg/kg (Devika P, Biomedical Pharmacotherapy, 2007). This is a preliminary study. However, there are many studies of large, longitudinal databases of human health and nutrition that show a large reduction in heart attacks among people who drink 5 or more cups of tea daily. Heart disease is usually the first or second leading cause of death in industrialized societies. EGCG Researchs: EGCG Helps Researchers Researchers have just announced a new way that EGCG, an antioxidant catechin from green tea, could help the development of new drugs with fewer side effects. One of the ways new drugs are developed is by targeting a specific cellular pathway. In the case of bacteria, a good target is an enzyme called DNA gyrase. DNA gyrase is required for bacterial reproduction. By stopping bacterial reproduction, researchers hope to stop debilitating infections. But bacterial DNA gyrase cannot act without the help of the energy molecule ATP, or adenosine triphosphate. Researchers seeking antibacterial drugs have tried to target the ATP binding site on DNA gyrase to stop its energy source, but so far have created chemicals with limited usefulness due to side effects. Now researchers in Slovenia have been able to track EGCG from green tea as it inhibits DNA gyrase. Using NMR spectroscopy, they have followed EGCG to the specific binding site on DNA gyrase where EGCG blocks ATP and thus prevents bacterial reproduction (Jerala R, Journal Medicinal Chemistry, 2007). This kind of technology has also helped HIV research show EGCG from green tea binding to a specific site on healthy cells used by HIV to enter and infect the cells. When EGCG was present, it could block HIV entry into the cell. Researchers hope that by following the successful protection of green tea's EGCG biochemistry, they can make proprietary drugs that mimic its effects. Hmmmmm....... EGCG Research: Green Tea EGCG, Parkinson's, and Alzheimer's Disease A preliminary study suggests that EGCG from green tea may protect against Alzheimer's disease and Parkinson's disease. Researchers used a laboratory model of Parkinson's disease where neuronal cells are damaged by paraquat, an herbicide used worldwide that is also toxic to dopaminergic brain cells associated with Parkinson's and some Alzheimer's. They found that adding EGCG (epigallocatechin gallate) from green tea reduced the deaths of paraquat damaged nerve cells. Protecting these specialized cells which are frequently damaged in Parkinson's disease is still only preliminary evidence for EGCG benefit. Larger studies with humans need to be explored. A possible explanation is that EGCG protects the cells by reducing enzymes and proteins that promote cell death or apoptosis, and by maintaining mitochondrial membrane integrity (Hou R, Cell Biology International, 2007). Daily green tea is the largest source of EGCG, a very powerful antioxidant with broad spectrum benefits.
Dragon Well Tea | Mao Feng Tea | Matcha Tea | Gunpowder Green Tea | Pi Lo Chun Tea | Gyokuro Tea | Lu shan Yun Wu Tea | Japanese Sencha Tea | Lu An Melon Seed Tea | Jasmine Tea |Blooming Tea | Chun Mee Tea
|
