Potential role of green tea catechins in various disease therapies: Progress and promise Mak 2012 Clinical and Experimental Pharmacology and Physiology Wiley Online Library

Potential role of green tea catechins in various disease therapies: Progress and promise Mak 2012 Clinical and Experimental Pharmacology and Physiology Wiley Online Library

Drinking green tea with starchy food may help lower blood sugar spikes

In continuation on my update on green tea

Mice fed an antioxidant found in green tea  epigallocatechin-3-gallate, or EGCG  and corn starch had a significant reduction in increase in their blood sugar  blood glucose  levels compared to mice that were not fed the compound, according to Joshua Lambert, assistant professor of food science in agricultural sciences.

The dose of EGCG fed to the mice was equivalent to about one and a half cups of green tea for a human. Lambert, who worked with Sarah C. Forester, postdoctoral fellow, and Yeyi Gu, graduate student, both in food science, said EGCG was most effective when the compound was fed to the mice simultaneously with corn starch. For humans, this may mean that green tea could help them control the typical blood sugar increases that are brought on when they eat starchy foods, like breads and bagels that are often a part of typical breakfasts.

"The spike in blood glucose level is about 50 percent lower than the increase in the blood glucose level of mice that were not fed EGCG," Lambert said. 

Green tea found to reduce rate of some GI cancers

In continuation of my update on green tea.

We know that, Tea contains polyphenols or natural chemicals that include catechins like EGCG and ECG. Catechins have antioxidant properties and may inhibit cancer by reducing DNA damage and blocking tumor cell growth and invasion.

Now researchers have found that regular tea consumption, defined as  tea  consumption  at  least three times a week for more than six months, was  associated  with  a  17 percent reduced risk of all digestive cancers combined. A  further  reduction  in  risk  was  found to be  associated  with  a increased level of tea drinking. Specifically, those who consumed about two to three cups per day (at least 150 grams of tea per month) had a 21 percent reduced risk of digestive system cancers.

For all digestive system cancers combined, the risk was reduced by 27 percent among women who had been drinking tea regularly for at least 20 years," said Nechuta. "For colorectal cancer, risk was reduced by 29 percent among the long-term tea drinkers. These results suggest long-term cumulative exposure may be particularly important."

Ref : http://ajcn.nutrition.org/content/96/5/1056

Green tea found to reduce rate of some GI cancers

GEN | News Highlights:Green Tea and Gold Nanoparticles Destroy Prostate Tumors

In continuation of my update on green tea

Scientists report on the development of a radioactive gold nanoparticle for prostate cancer therapy that they claim is far less toxic to normal tissues than traditional radiation therapy and results in massive reduction in tumor volume and increased survival in experimental mice after just one dose. The nanoparticles, derived from the Au-198 isotope, incorporate an extract from green tea known as epigallocatechin-gallate (EGCg), which effectively latches the nanoparticles onto the prostate tumor cells and facilitates their internalization.

GEN | News Highlights:Green Tea and Gold Nanoparticles Destroy Prostate Tumors

Beehive Extract Shows Potential as Prostate Cancer Treatment

 Caffeic acid phenethyl ester, or CAPE (see below structure), is a compound isolated from honeybee hive propolis, the resin used by bees to patch up holes in hives. Propolis has been used for centuries as a natural remedy for conditions ranging from sore throats and allergies to burns and cancer. But the compound has not gained acceptance in the clinic due to scientific questions about its effect on cells. 

In a paper published in Cancer Prevention Research, researchers combined traditional cancer research methods with cutting-edge proteomics to find that CAPE arrests early-stage prostate cancer by shutting down the tumor cells' system for detecting sources of nutrition.

"If you feed CAPE to mice daily, their tumors will stop growing. After several weeks, if you stop the treatment, the tumors will begin to grow again at their original pace," said Richard B. Jones, PhD, assistant professor in the Ben May Department for Cancer Research and Institute for Genomics and Systems Biology and senior author of the study. "So it doesn't kill the cancer, but it basically will indefinitely stop prostate cancer proliferation." 

Natural remedies isolated from plant and animal products are often marketed as cure-alls for a variety of maladies, usually based on vague antioxidant and anti-inflammatory claims. While substances such as ginseng or green tea have been occasionally tested in laboratories for their medicinal properties, scientific evidence is commonly lacking on the full biological effects of these over-the-counter compounds.

"It's only recently that people have examined the mechanism by which some of these herbal remedies work," Jones said. "Our knowledge about what these things are actually doing is a bit of a disconnected hodge-podge of tests and labs and conditions. In the end, you're left with a broad, disconnected story about what exactly these things are doing and whether or not they would be useful for treating disease."

To study the purported anti-cancer properties of CAPE, first author Chih-Pin Chuu (now at the National Health Research Institutes in Taiwan) tested the compound on a series of cancer cell lines. Even at the low concentrations expected after oral administration, CAPE successfully slowed the proliferation of cultured cells isolated from human prostate tumors.

CAPE was also effective at slowing the growth of human prostate tumors grafted into mice. Six weeks of treatment with the compound decreased tumor volume growth rate by half, but when CAPE treatment was stopped, tumor growth resumed its prior rate. The results suggested that CAPE stopped cell division rather than killing cancerous cells.

To determine the cellular changes that mediated this effect, the researchers then used an innovative proteomics technique invented by Jones and colleagues called the "micro-western array." Western blots are a common laboratory tool used to measure the changes in protein levels and activity under different conditions. But whereas only one or a few proteins at a time can be monitored with Western blots, micro-western arrays allow researchers to survey hundreds of proteins at once from many samples.

Chuu, Jones and their colleagues ran micro-western arrays to assess the impact of CAPE treatment on the proteins of cellular pathways involved in cell growth -- experiments that would have been prohibitively expensive without the new technique.

"What this allowed us to do is screen about a hundred different proteins across a broad spectrum of signaling pathways that are associated with all sorts of different outcomes. You can pick up all the pathways that are affected and get a global landscape view, and that's never been possible before," Jones said. "It would have taken hundreds of Westerns, hundreds of technicians, and a very large amount of money for antibodies."

The micro-western array results allowed researchers to quickly build a new model of CAPE's cellular effects, significantly expanding on previous work that studied the compound's mechanisms. Treatment with CAPE at the concentrations that arrested cancer cell growth suppressed the activity of proteins in the p70S6 kinase and Akt pathways, which are important sensors of sufficient nutrition that can trigger cell proliferation.

"It appears that CAPE basically stops the ability of prostate cancer cells to sense that there's nutrition available," Jones said. "They stop all of the molecular signatures that would suggest that nutrition exists, and the cells no longer have that proliferative response to nutrition."

The ability of CAPE to freeze cancer cell proliferation could make it a promising co-treatment alongside chemotherapies intended to kill tumor cells. Jones cautioned that clinical trials would be necessary before CAPE could be proven effective and safe for this purpose in humans. But the CAPE experiments offer a precedent to unlock the biological mechanisms of other natural remedies as well, perhaps allowing these compounds to cross over to the clinic.

"A typical problem in bringing some of these herbal remedies into the clinic is that nobody knows how they act, nobody knows the mechanism, and therefore researchers are typically very hesitant to add them to any pharmaceutical treatment strategy," Jones said. "Now we'll actually be able to systematically demonstrate the parts of cell physiology that are affected by these compounds."

Ref : http://cancerpreventionresearch.aacrjournals.org/content/5/5/788

Green tea shows promise against two types of tumors, HHS

In continuation of my update on green tea

Researchers lead by  Dr. Thomas Smith at The Donald Danforth Plant Science Center and his colleagues at The Children’s Hospital of Philadelphia, have found that a compound found in green tea shows great promise for the development of drugs to treat two types of tumors and a deadly congenital disease. 

Dr. Smith and his colleagues discovered that two compounds found naturally in green tea are able to compensate for this genetic disorder by turning off GDH in isolated and when the green tea compounds were administered orally. The Smith lab also used X-ray crystallography to determine the atomic structure of these green tea compounds bound to the enzyme. With this atomic information, they hope to be able to modify these natural compounds to design and develop better drugs. 

Interestingly, two other research groups have validated and extended these findings to demonstrate that blocking GDH with green tea is very effective at killing two different kinds of tumors; glioblastomas, an aggressive type of brain tumor, and tuberous sclerosis complex disorder, a genetic disease that causes non-malignant tumors to grow on a number of organs. 

More...  

Protective properties of green tea uncovered

In continuation of my up date on the benefits of green tea...

Protective properties of green tea uncovered

Ref : doi:10.1016/j.phymed.2010.11.004

Endothelial Function Improvement With Dietary (Cocoa) Flavanols in Patients With Coronary Artery Disease....

A new study by UCSF cardiologists and researchers lead by Dr. Yerem Yeghiazarians found that high concentrations of cocoa flavanols decrease blood pressure, improve the health of blood vessels and increase the number of circulating blood-vessel-forming cells in patients with heart disease. The findings indicate that foods rich in flavanols  such as cocoa products, tea, wine, and various fruits and vegetables have a cardio-protective benefit for heart disease patients.

Flavanols are phytonutrient compounds that are found naturally in apples, grapes, tea, cocoa and cherries, which account for the antioxidant effect provided by red wine and green tea. The study found a protective effect from a cocoa drink with 375 mg of flavanols, but according to researchers, a standard or recommended dosage has not yet been defined to achieve optimal health benefit.

The UCSF team has shown for the first time that one of the possible mechanisms of flavanol's benefit is an increase in the circulation of so-called angiogenic cells in the blood. These cells, also known as early endothelial progenitor cells, are critical for the repair process after vascular injury, and perform function and maintenance roles in the endothelium. Endothelium is the thin layer of cells that line the interior wall of blood vessels.

In the current study, the benefit seen from the two-fold increase in circulating angiogenic cells was similar to that achieved by therapy with statins and with lifestyle changes such as exercise and smoking cessation. The benefit demonstrated with cocoa flavanol therapy occurred in addition to the medical regimen already being taken by study participants.

"Our data support the concept that dietary flavanols at the levels provided -- in tandem with current medical therapy -- are safe, improve cardiovascular function, and increase circulating angiogenic cells, which have previously been shown to correlate positively with long-term cardiovascular outcomes" said Yeghiazarians.

Though long-term trials examining the effects of high-flavanol diets on cardiovascular health and function are warranted, but these early findings help us understand how these compounds impact the function of damaged blood vessels...

Ref : Yerem Yeghiazarians et.al., J. Am. Coll. Cardiol., July 13, 2010; 56: A20. 

ProstaCaid (33-ingredient comprehensive polyherbal preparation) against prostate cancer......

We have seen  many benefits of natural products rich in  Quercetin,   Epigallocatechin gallate (EGCG) and many other polyphenol antioxidant from natural products like green tea, broccoli peaches and plums. Interestingly, now researchers from  Columbia University have come up with an interesting finding, i.e., ProstaCaid is a 33-ingredient comprehensive polyherbal preparation with supplements of vitamin C, vitamin D3, zinc, selenium, quercitin, 3,3′-diinodolymethane (DIM), and lycopene was able to stop abnormal cell growth and induce apoptosis (programmed cell death) in both hormone sensitive and hormone resistant prostate cancer cell lines at unusually low concentrations, which makes the findings more significant...

Herbal extracts include the extracts from turmeric root, saw palmetto berry, grape skin, pomegranate, pumpkin seed, pygeum bark, sarsaparilla root, green tea, and Japanese knotweed. Hence, it is rich in natural polyphenols, including quercetin, resveratrol, epigallocatechin gallate (EGCG), and ellagic acid, which have previously demonstrated anticancer potential. The unique formula contains 3 medicinal mushrooms grown on an herbal-enhanced medium. The mushrooms included are Phellinus linteus, Ganoderma lucidum, and Coriolus versicolor, each with known anticancer properties.

Researchers claim that, ProstaCaid was designed based on constituents that exhibit antiprolifetaive, antioxidant, and apoptotic activities; however, its efficacy and the mechanisms of action are yet to be examined. Researchers looked at the effectiveness of the preparation in suppressing several types of prostate cancer cell lines in culture and attempt to delineate the mechanism of action for justification in pursuing animal to determine efficicacy invivo.

Researchers conclude that, the anticancer activity of ProstaCaid may be ascribed to its polyphenolic flavonoids and curcuminoids derived from various herbs as well as other supplements, such as DIM. The preparation contains supplements such as quercetin (15%), Curcuma longa root extract complex with enhanced bioavailability (BCM-95; 20%), DIM (3%), and resveratrol (0.2%). Some of these components have shown a strong doseand time-dependent growth inhibition and apoptotic death in prostate cancer cells; 25 mM of quercetin inhibited about 50% PC3 cell growth for 72 hours. At 24 hours, 50 mM and 100 mM quercetin induced G2/M arrest and apoptosis, manifested by the decrease in G2/M-related protiens.

Researchers summarise  that,    ProstaCaid has anti-cancer activities in both AD and AI prostate cancer cells at very low concentrations (25 mg/mL). It also suggests that ProstaCaid inhibits cell growth and survival, at least through the inhibition of AKT and MAPK signaling. The effect on AI cell lines is especially of importance as there is presently no curative therapy for hormone refractory prostate cancer.

Researchers postulate that ProstaCaid may affect activity of Cdc2/cyclin B1 kinase by reducing this complex formation. Cdc2 could be dephosphorylated by Cdc25C and become inactive or be phosphorylated by protein kinase, such as Wee1, and then converted into an inactive form. They also suggest that more studies are needed in the future to test it and to define its upstream events in PC3 cells.

Ref : Jun Yan and Aaron E. Katz, Integr Cancer Ther 2010 9: 186

Polyphenols in red wine and green tea halt prostate cancer growth, study suggests

In continuation of my update on Green Tea and EGCG........

"The profound impact that the antioxidants in red wine and green tea have on our bodies is more than anyone would have dreamt just 25 years ago," Weissmann added. "As long as they are taken in moderation, all signs show that red wine and green tea may be ranked among the most potent 'health foods' we know." ....

Polyphenols in red wine and green tea halt prostate cancer growth, study suggests

New study finds green tea extract may prevent Alzheimer's disease and dementia

In continuation of my update on green tea benefits......

New study finds green tea extract may prevent Alzheimer's disease and dementia

New evidence that green tea may help fight glaucoma and other eye diseases

In continuation of my update on green tea and its usefulness, I am sharing herewith this interesting article, where in the researchers claim that there is a possibility that green tea may protect against glaucoma and other common eye diseases.....

New evidence that green tea may help fight glaucoma and other eye diseases

Green tea might help to treat Uterine Fibroids....

In continuation of my update on green tea   (pic : source : greenteatruth.org ).......  

We have seen many research groups  trying to explore the  usefulness of  green tea for reduction in heart disease (bad cholesterol),  increase in metabolic rate (fat oxidization) prevention  of Alzheimer’s or Parkinson’s diseases, lowering incidence of cancers and  weight reduction.

 Now researchers from Meharry Medical College in Nashville, Tenn lead  Dr. Ayman Al-Hendy ,   have found that green tea extract shows promise as a treatment for uterine fibroids. The key ingredient responsible for this activity is  "epigallocatechin gallate (EGCG)". The researchers investigated  the effect of epigallocatechin gallate  on rat leiomyoma (ELT3) cells in vitro and in a nude mice model. ELT3 cells were treated with various concentrations of EGCG. Cell proliferation, proliferation cell nuclear antigen (PCNA), and cyclin-dependent kinase 4 (Cdk4) protein levels were evaluated. As per the claim by the researchers, EGCG significantly decreased PCNA and Cdk4 protein levels. The authotrs conclude that EGCG effectively inhibits proliferation and induces apoptosis in rat ELT3 uterine leiomyoma cells in vitro and in vivo.

Ref : http://www.ajog.org/article/S0002-9378%2809%2902102-4/fulltext

Quercetin blocks Hepatitis C infection....

The conventional treatments for hepatitis C are interferon and ribavirin, which can cause major side effects and aren't effective in all patients. But something interesting and unique has been achieved  by UCLA researchers.

As per the claim by the lead researcher Samuel French Assistant Professor, Pathology of UCLA, they have  identified major two cellular proteins (HSPs, heat shock proteins 40 and 70) that play an important role in hepatitis C infection, and they say the finding may point to new and less toxic treatments for the disease, which can lead to cirrhosis and liver cancer. The researchers also found that Quercetin,  blocks the synthesis of two heat shock proteins 40 and 70proteins  and significantly inhibited viral infection in tissue culture.

 

Quercetin (see the structure) :  

Is a plant-derived flavonoid, specifically a flavonol, used as a nutritional supplement. Laboratory studies show it may have anti-inflammatory and antioxidant properties,  and it is being investigated for a wide range of potential health benefits.Interestingly American cancer society, says that while quercetin has been promoted as being effective against a wide variety of diseases, including cancer, There is current early-stage clinical research on quercetin addressing safety and efficacy against sarcoidosis, asthma and glucose absorption in obesity and diabetes. Food riches in Quercetin includes, capers, lovage, apples, tea (Camellia sinensis), onion, especially red onion (higher concentrations of quercetin occur in the outermost rings), red grapes, citrus fruit, tomato, broccoli and other leafy green vegetables, cherries and berries.

Significant claims by the researchers are ;

a. quercetin targets cellular proteins rather than viral proteins, there is less likelihood of developing viral

    resistance (cellular proteins cannot change like viral proteins can);

b. quercetin may allow for the dissection of the viral life cycle and has potential therapeutic use to reduce
    virus  production with low associated toxicity.

Hope the researcher will have positive results from the phase 1 clinical trial.....

Ref :http://www.cancer.ucla.edu/Index.aspx?page=644&recordid=312

Gren tea for new type of H1N1 Flu ......

In continuatation of my update on Epigallocatechin gallate (EGCg), I find this info something different and interesting too. We are aware about the antioxidant and anticancer activities of this compound, but now researchers from Central Research Institute of ITO EN, Ltd., & School of Pharmaceutical Sciences, University of Shizuoka have found the same compound to inhibits flu infection. As per the researchers claim, the compound had an inhibitory effect against three types of influenza viruses, including the swine-origin H1N1 virus that caused pandemic flu in 2009, and that its effect did not depend on the type of virus. These findings once again suggest that green tea is effective in preventing flu.

Gargling with green tea has already proved to prevent the onset of seasonal flu. It has become clear that catechin, a major type of polyphenol in green tea, plays a major role in prevention of flu infection, and that, among different types of catechin, EGCg displays the strongest antiviral activity. More interestingly, the researchers have conducted examinations to see if EGCg also shows antiviral activity against the new type of H1N1 virus, regardless of viral subtypes.

Solutions containing three types of viruses including the H1N1 virus were mixed with EGCg extracted from green tea. The mixture was added to cultured cells, which were thus infected. The cells were incubated for a set period of time, and the number of infected cells was counted. The concentration of EGCg at which virus infection was inhibited to 50% of the level of infection without EGCg was calculated.

The experiments showed that EGCg prevented flu virus infections at lower concentrations than Amantadine (a drug used to prevent and treat flu). A typical concentration of EGCg in green tea infused from a teapot is reported as 5,000-7,000 micromoles/L. Therefore, these results indicate that green tea diluted 1,000-fold or more is effective to halve infections by three types of viruses, including H1N1.

Those interested to know the details about green tea can visit the site.

Ref : http://www.itoen.co.jp/eng/corporate_info/index.html

Combination of EGCG & DAPH-12 - a treatment for brain disorders ?

Amyloid plaques are tightly packed sheets of proteins that infiltrate the brain. These plaques, which are stable and seemingly impenetrable, fill nerve cells or wrap around brain tissues and eventually (as in the case of Alzheimer's) suffocate vital neurons or brain cells, causing loss of memory, language, motor function and eventually premature death.

To date, researchers have had no success in destroying plaques in the human brain and only minimal success in the laboratory. One reason for these difficulties in finding compounds that can dissolve amyloids is their immense stability and their complex composition.

Yet, Dr. Duennwald ( Boston Biomedical Research Institute , BBRI) and co workers from Pennsylvania School of Medicine, experienced success in previous studies when he exposed amyloids in living yeast cells to EGCG (see the above structure). Furthermore, he and his collaborators also found before that DAPH-12, (see below structure) too, inhibits amyloid production in yeast.

About EGCG :

Epigallocatechin gallate, also known as Epigallocatechin 3-gallate, is the ester of epigallocatechin and gallic acid and a type of catechin. EGCG is the most abundant catechin in most notably tea, among other plants, and is also a potent antioxidant and that may have therapeutic properties for many disorders including cancer. It is found in green tea, but not black tea, as EGCG is converted into thearubigins in black teas. EGCG can be found in many supplements.

These findings are significant because it is the first time a combination of specific chemicals (EGCG & DAPH-12) has successfully destroyed diverse forms of amyloids at the same time.

Though the detailed mechanism is still to be established, its a good achievement and hope this combinatorial therapy will help those sufferings from Alzheimer's and other degenerative diseases (Huntington's, and Parkinson's) in the days to come.....

Ref : http://www.nature.com/nchembio/journal/v5/n12/pdf/nchembio.246.pdf

Green tea prevents the development of hepatic fibrosis in rat model of DMN-induced liver fibrosis

Green tea prevents the development of hepatic fibrosis in rat model of DMN-induced liver fibrosis

Patients with chronic hepatitis C can benefit by drinking coffee

Patients with chronic hepatitis C and advanced liver disease who drink three or more cups of coffee per day have a 53% lower risk of liver disease progression than non-coffee drinkers according to a new study. The study found that patients with hepatitis C-related bridging fibrosis or cirrhosis who did not respond to standard disease treatment benefited from increased coffee intake. An effect on liver disease was not observed in patients who drank black or green tea.

Read......

Patients with chronic hepatitis C can benefit by drinking coffee