Showing posts sorted by relevance for query Catechin. Sort by date Show all posts
Showing posts sorted by relevance for query Catechin. Sort by date Show all posts

Monday, December 7, 2009

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

Tuesday, December 29, 2009

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

Tuesday, October 15, 2019

Is Green Tea a Fad or a Real Health Boost?


In continuation of my updates on Green tea
Image result for green tea
Green tea is a popular health trend, with many people sipping in hopes of deriving benefits from the brew.
There's nothing wrong with that, dietitians say -- green tea is a healthy drink loaded with antioxidants. But the jury's still out on many of its purported health benefits.
"Clinical trials related to green tea are still in their early stages," said Nancy Farrell Allen, a registered dietitian nutritionist in Fredericksburg, Va. "I say drink it, enjoy it. It's not going to hurt, and it might have worthy benefits to it. But nutrition is a science, and it takes time for our understanding to evolve."
Green tea's potential health benefits derive from catechins, which are powerful antioxidant compounds known as flavonoids, said Chelsey Schneider, clinical nutrition supervisor at Mount Sinai Beth Israel Cancer Center in New York City.
One catechin in particular, known as EGCG, is found at higher levels in green tea than in either white or black tea, she said.
"This compound can be even stronger than vitamin C and E, which are very, very strong antioxidants," Schneider said. Antioxidants help prevent damage to cells.
Green, black and white tea all come from the same plant, said Allen, who is a spokeswoman for the Academy of Dietetics and Nutrition.
Green tea is made from the leaves of the mature plant, while white tea is made of leaves plucked early in development. Black tea is made from green tea leaves that are laid out and covered with a damp cloth, she said.
"They dry and blacken and ferment a little, giving black tea that darker, richer flavor," Allen said. But this process also reduces levels of catechins in black tea.
Weight loss has been associated with green tea, with experts suggesting that its mixture of caffeine and catechins can enhance a person's metabolism and processing of fat, according to the University of California-Davis Department of Nutrition.
But it appears that folks have to drink a lot of green tea to get substantial weight loss benefits and carefully watch the rest of their diet, UC-Davis says.
Green tea also has been tied to heart health.
For example, green tea was shown to reduce "bad" LDL cholesterol in a 2018 study of more than 80,000 Chinese published in the Journal of the American Heart Association.
Evidence suggests catechins in green tea also could lower risk of heart attacks, help blood vessels relax and reduce inflammation, UC-Davis says.
Green tea even has been associated with a lower risk of some cancers.
The American Cancer Society says studies have linked green tea to a reduction in ovarian cancer risk. And UC-Davis said experimental models have shown that green tea might reduce risk of a variety of other cancers.
But a 2016 evidence review by the Cochrane Library concluded that there is "insufficient and conflicting evidence to give any firm recommendations regarding green tea consumption for cancer prevention."
Schneider said the research is limited. "Some small studies say green tea can maybe be preventative for certain cancers, like breast, ovarian, endometrial, pancreatic and oral cancers, but there aren't so many conclusive human trials that support that," she said.
Green tea also might help keep your brain younger. A 2014 study in the journal PLOS One found that Japanese who drank more green tea had significantly less decline in brain function, although researchers couldn't rule out the possibility that these folks might have other healthy habits that helped keep them mentally sharp.
One caveat with all of this research is that it tends to take place in Asian countries, where people drink much more green tea. There might be significant differences for Americans.
And the way you take your green tea could diminish any potential positive effects, Schneider added.
"A lot of people are adding processed white sugar to their green tea, which really makes something beautiful and healthy into something unhealthy," she said.
Adding milk or cream to your tea also might not be a good idea.
"There are some studies that say having milk in green tea can actually block the effects of you absorbing the antioxidant," Schneider said. "If it was me, I'd drink it straight up."

Thursday, March 4, 2010

Pycnogenol counteracts kidney damage due to hyprtension...

Pycnogenol® is the patented trade name for a water extract of the bark of the French maritime pine (Pinus pinaster ssp. atlantica), which is grown in coastal southwest France.  Pycnogenol® contains oligomeric proanthocyanidins (OPCs) as well as several other bioflavonoids (catechin, epicatechin), phenolic fruit acids (such as ferulic acid and caffeic acid), and taxifolin. Procyanidins are oligometric catechins found at high concentrations in red wine, grapes, cocoa, cranberries, apples, and some supplements such as Pycnogenol.

Scientific evidence on its antioxidative capacity and protective action on the vascular system have been published in the most renowned scientific journals. Additional published findings have demonstrated Pycnogenol’s beneficial effects in cardiovascular health (reduces LDL), skincare (e.g., Melasma, erythema, Chronic venous insufficiency), cognitive function, diabetes health, inflammation, sports nutrition, asthma and allergy relief and menstrual disorders, among others.

Earlier research suggested that, supplementation of Pycnogenol® with  conventional diabetes treatment may lower glucose levels and improve endothelial function and may improve symptoms associated with diabetic microangiopathy.

Now researchers lead by Dr. Gianni Belcaro, have come up with an interesting finding.i.e.,  Pycnogenol®  counteracts kidney damage caused by hypertension, lowering urinary proteins and improving blood flow to the kidneys.

The randomized, controlled study conducted by the G D'Annunzio University in Italy investigated 55 hypertensive patients who showed early signs of impaired kidney function, as judged by elevated amounts of proteins found in their urine.  The patients were divided into two groups.  Both groups were treated with anti-hypertensive medication Ramipril and one group of 29 patients took Pycnogenol in addition to the Ramipril.

After six months of treatment with Ramipril, average protein levels decreased to 64 mg per 24-hour period, remaining well above an acceptable level.  Conversely, the group taking Pycnogenol® as an adjunct to Ramipril had an average of only 39 mg per 24-hour period, a decrease of nearly double compared with anti-hypertensive medication taken alone.

The study also found a statistically significant decrease in patients' blood pressure when taking Pycnogenol® in conjunction with Ramipril.  As per the clam by the researchers, the addition of Pycnogenol® decreased both systolic and diastolic pressures by an additional three to six percent.  Pycnogenol® was also found to lower the patients' elevated levels of inflammatory marker CRP, a blood protein associated with the risk for acute cardiovascular events such as heart attack, reducing values to a healthy level.

Researchers conclude that, Pycnogenol® as an adjunct to the medication produced significantly greater results, particularly for kidney function restoration  and Pycnogenol® continues to demonstrate its abilities as a natural solution for the complete cardiovascular system....

Ref :  Dr. Gianni Belcaro et.al., March 2010, Journal of Cardiovascular Pharmacology...

Sunday, September 6, 2009

Fruits better than prviously thought !.......

Polyphenol content in fruits usually refers to extractable polyphenols, but a Spanish scientist working at the Institute of Food Research in Norwich analysed apple, peach and nectarine. She found that nonextractable polyphenol content is up to five times higher than extractable compounds. Its really interesting and that might be the reason why our forefathers used to insist to eat whole fruits (though they might not have studied so exhaustively... !).  

The interesting findings like,  "polyphenols need to be treated with acid to extract them from the cell walls of fruit in the lab" will help at least now onwards to collect all the useful polyphenols (proanthocyanidins, ellagic acid and catechin)  which without this new findings might have gone as waste.  Dr Paul Kroon from IFR explains: “In the human body these compounds will be fermented by bacteria in the colon, creating metabolites that may be beneficial, for example with antioxidant activity. 

Hope these  nonextractable polyphenols, (which mostly escape analysis and are not usually considered in nutritional studies),  will play a major part of bioactive compounds in the diet  in the days to come. Congrats Professor Saura-Calixto, for this  achievement.....


Monday, September 7, 2015

Green tea components may help prevent prostate cancer development in at-risk men


Structural formula of epigallocatechin gallate
In continuation from my update on epigallocatechin

Prostate cancer is the second most common type of cancer in men and is predicted to result in an estimated 220,00 cases in the United States in 2015. In recent years, an emphasis has been placed on chemoprevention - the use of agents to prevent the development or progression of prostate cancer. A team of researchers led by Nagi B. Kumar, Ph.D., R.D., F.A.D.A. at Moffitt Cancer Center recently published results of a randomized trial that assessed the safety and effectiveness of the active components in green tea to prevent prostate cancer development in men who have premalignant lesions. The results will be presented at the 2015 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.

Twenty percent of green tea is consumed in Asian countries where prostate cancer death rates are among the lowest in the world and the risk of prostate cancer appears to be increased among Asian men who abandon their original dietary habits upon migrating to the U.S.

Laboratory studies have shown that substances in green tea called, "catechins" inhibit cancer cell growth, motility and invasion, and stimulate cancer cell death. Green tea catechins also prevent and reduce tumor growth in animal models. Epigallocatechin-3-gallate (EGCG) is the most abundant and potent catechin found in green tea responsible for these cancer prevention effects.

The goal of this trial was to evaluate if a one-year intervention with green tea catechins could suppress prostate cancer development in men who had high-grade intraepithelial neoplasia (HGPIN) or atypical small acinar proliferation (ASAP). The researchers used decaffeinated green tea capsules called Polyphenon E that contained a mixture of catechins that predominantly contained EGCG at a dose of 200 mgs twice a day.

Monday, June 12, 2017

Seeds of tropical shrub guarana contain ten times more amount of catechins than green tea



 Image result for guarana (Paullinia cupana)



In continuation of my update on catechins

The millions of people who consume green tea all over the world benefit from the catechins it contains. Catechins are a class of chemical compounds with anti-oxidant and anti-inflammatory properties, among other healthy ingredients. Researchers at the University of São Paulo's Public Health School (FSP-USP) have discovered that guarana (Paullinia cupana) is a worthy competitor, at least as far as catechins are concerned: the seeds of the tropical shrub, used in fizzy drinks that are among the most popular in Brazil, as well as in over-the-counter supplements, contain more than ten times the amount of catechins found in green tea.


Chemical structure of (+)-Catechin Catechins

A clinical trial with healthy human volunteers has demonstrated that guarana is a rich source of catechins, which, when properly absorbed, reduce the oxidative stress associated with the development of neurodegenerative and cardiovascular disorders, as well as diabetes, cancer, inflammation and premature aging due to cell death, among other conditions harmful to health and wellbeing.

"Guarana has always been seen above all as a stimulant, especially by the international scientific community, because of its high caffeine content. We also found few Brazilian scientific studies that seek to identify other biological effects of guarana," said Lina Yonekura, the principal investigator for this research and currently an assistant professor at Kagawa University's School of Agriculture in Japan. "This pioneering assessment of the absorption and biological effects of its catechins in human volunteers should foster interest in guarana as a functional food on the part of scientists, the market, and society in general."

The paper with the results of the study is featured on the cover of the latest issue ofFood & Function, published by the Royal Society of Chemistry in the United Kingdom as one of the "Hot Articles in Food & Function 2016.

The month-long study was conducted in two stages. After selecting volunteers who were healthy but slightly overweight and with a moderately elevated risk of cardiovascular disease, the researchers measured baseline parameters on the first day and evaluated the same items again on day 15 after a the implementation of a controlled diet.

The participants were then asked to take guarana at home every morning before breakfast for the next fortnight. They were given bottles containing guarana seed powder and instructed to prepare a daily drink with the contents of one bottle (3 g of guarana powder) in 300 mL of water.

This procedure ensured that each participant acted as his or her own control. The researchers compared the same volunteers' blood tests at different times to avoid the influence of variability between individuals. The acute effect of guarana was measured one hour after the participants drank the solution on day 1 and day 15. The prolonged effect was assessed after overnight fasting on the same days.

The researchers assessed the extent to which guarana affected oxidative stress markers during the two-week intervention period. They also performed a detailed study to evaluate the subjects' absorption of catechins and their metabolites, as they had found no information in the scientific literature on the bioavailability of these compounds in guarana.

The oxidative stress markers included oxidation of low-density lipoprotein (LDL), popularly known as bad cholesterol. LDL is essential to an organism's proper functioning because it is the main particle that carries cholesterol to cells. Cholesterol is a structural component of all cell membranes and is used to manufacture steroid hormones (estrogen and testosterone). When oxidized, however, LDL causes atherosclerosis and increases the risk of cardiovascular disease. The tests performed by Yonekura's team showed an increase in oxidation resistance of the LDL in the blood samples taken from the volunteers after they drank guarana.

They also performed a comet assay, also called single cell gel electrophoresis (SCGE), a technique for quantifying and analyzing DNA damage in individual cells due to various factors, including oxidative stress. In this case, lymphocyte DNA in blood samples taken one hour after guarana intake was less damaged than expected when submitted to an oxidizing environment, indicating the presence of anti-oxidant substances or enhanced performance of the lymphocytes' enzymatic anti-oxidant system.

"All these markers depend on the presence of catechins in the bloodstream," Yonekura said. "The improvement in the parameters we assessed was associated with a rise in the concentration of plasma catechins after guarana intake, showing that guarana was indeed responsible for this effect."

Moreover, she went on, the guarana catechins strengthened the cells' native anti-oxidant enzymes, especially glutathione peroxidase, catalase, and superoxide dismutase, which combine to convert superoxide into peroxide and finally into water, protecting cells from the oxidative damage caused by their own metabolism of outside factors.

The tests showed increased glutathione peroxidase and catalase activity both shortly after guarana ingestion and on the following day.

"These results are exciting, suggesting that the bioavailability of guarana catechins is equal to or greater than that of green tea, cocoa and chocolate catechins," Yonekura said. "In fact, their bioavailability was sufficient to have a positive effect on plasma anti-oxidant activity, protect erythrocyte DNA, reduce plasma lipid oxidation, and increase anti-oxidant enzyme activity. We hope the results lead to heightened interest in guarana as the species is native to the Amazon, and Brazil is practically the only country that produces it on a commercial scale."