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

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

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.

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

Drinking tea flavored with herbs may improve mood and memory

  Chamomile      Rosemary 

 Peppermint

The herbs peppermint, chamomile, rosemary and lavender have been proven to have an impact on mood and memory, with significant benefits displayed for older people, according to new research from Northumbria University.

Researchers from the University's Department of Psychology have found that drinking peppermint tea improves alertness, while chamomile tea has a calming effect. They also found that smelling the aromas of rosemary and lavender impacted on memory in people over 65, with the scent of rosemary enhancing their memory, while lavender impaired it.

The findings have been presented at the annual British Psychological Society Conference in Nottingham this week (26-28 April 2016).

In one study, the researchers asked 180 volunteers to consume either a chamomile or peppermint tea drink and tested their cognition and mood before and after drinking. A control group drank hot water for comparison.

They found that peppermint enhanced and aroused both mood and cognition, helping to improve long term memory, working memory and alertness, while chamomile had a calming and sedative effect which significantly slowed memory and attention speed.

In a separate study, 150 healthy people aged 65 and over were placed in rooms which had been scented with rosemary and lavender essential oils, or a control room which had no scent. They were asked to undertake tests that assessed their prospective memory - the ability to remember to do something at a given time, such as taking medication, or after receiving a prompt, such as posting a letter after seeing a post box. They also completed a mood assessment test.

Those who had been in the rosemary scented room displayed significantly enhanced prospective memory, with test scores 15% higher than those who had been in the room with no aroma. They were also more alert.

In contrast, those who had spent time in the lavender scented room displayed significantly increased calmness and contentedness, with a decrease in their ability to remember to do something at a given time.

Dr Mark Moss, Head of the Department of Psychology, said: "Peppermint has a reputation for being psychologically or mentally alerting. It picks you up and makes you feel a little bit brighter, so we endeavoured to test this out by giving people peppermint tea, or chamomile tea, which is a more calming drink and then put them through some computerised tests. We found that those people who had drunk the peppermint tea had better long-term memory. They were able to remember more words and pictures that they had seen. In contrast, the people who had the chamomile were slower in responding to tasks.

"Rosemary meanwhile has a reputation about being associated with memory - even Shakespeare said 'rosemary is for remembrance' - and it's also associated with being invigorating. We have found that people are more alert after being in a room that has rosemary aroma in it. We tested prospective memory - our ability to remember to remember to do something - on people over 65 years of age, to see if we could improve their ability and we found that rosemary could do that. This is potentially very important because prospective memory, for example, enables you to remember to take your medication at certain times of the day.

Drinking tea flavored with herbs may improve mood and memory

Matcha green tea kills breast cancer stem cells

MATCHA, the Green Tea packed with antioxidants, is often hailed as containing properties which prevent disease.

Scientists in Salford, UK have shed a ray of light on the claim by testing it on cancer stem cells - with surprising results.

In research published in the journal Aging, a team from the Biomedical Research Centre at the University of Salford, used metabolic phenotyping on cell lines of breast cancer stem cells and found that Matcha "shifted cancer cells towards a quiescent metabolic state" and stopped their spread at a relatively low concentration (0.2 mg/ml).

They also found that the signaling pathways that promote cancer stem cells indicated that Matcha "strongly affected mTOR signals, weakening components of the 40S ribosome. This raised the possibility that Matcha could be used in place of chemical drugs such as rapamycin.

Michael Lisanti, professor of translational medicine at the center, explained: "Matcha green tea is a natural product used as a dietary supplement with great potential for a range of treatments. But, the molecular mechanism underpinning all that remains largely unknown.

"By using metabolic phenotyping, we found that the tea is suppressing oxidative mitochondrial metabolism - in other words it is preventing the cells from 're-fuelling' and therefore they become inactive and die.

"The effects on human breast cancer cells were very striking; the active ingredients in matcha having a surgical effect in knocking out certain signaling pathways.

"Our results are consistent with the idea that Matcha may have significant therapeutic potential, mediating the metabolic reprogramming of cancer cells."

The team who specialize in identifying non-toxic methods of killing cancer stem cells recently found that Earl Grey tea ingredient, Bergamot kills cancer cells and works as an anti-cholesterol agent.

Ref : https://www.salford.ac.uk/news/articles/2018/green-tea-prevent-cancer-cells-from-refuelling

Plant flavonols significantly reduce Alzheimer’s risk

A new study published in the journal Neurology in January 2020 concludes that increasing the intake of plant flavonols steeply reduces the risk of Alzheimer’s dementia (AD) by up to a half. In other words, AD could be prevented in many people simply by regularly eating and drinking more foods containing these compounds such as tea, oranges, and broccoli.

Alzheimer’s disease

AD is a progressive brain disorder in which the individual loses cognitive skills, including memory and thinking skills, and the ability to perform simple tasks. It is by far the leading cause of such disorders and affects over 5 million Americans.

One study was carried out on over 900 people, who were part of a community-wide ongoing larger research project called the Rush Memory and Aging (MAP) Project. These participants were assessed yearly for their neurologic health and dietary patterns, for an average of 6 years, but some for as long as 12 years. The average age was 81 years, and 3 out of 4 were female.

The findings

In the first study, 220/921 participants developed AD during the study. The risk of AD fell with a greater intake of flavonols. This finding held good even after the researchers adjusted for other health-associated factors – because those with the highest total flavonol intake were also the best educated, most active and took part in more cognitive activities. They also accounted for genetic factors like the presence of the APOE4 gene, and for cardiovascular risk factors that could influence the risk of AD, such as diabetes mellitus, history of heart attack, or stroke, or hypertension.

When classified into five groups based on decreasing flavonol intake, the participants in the first group (highest intake) consumed over 15 mg of flavonols a day. Compared to those in the lowest fifth (about 5 mg a day), these individuals showed an approximately 50% reduction in AD risk.

In concrete terms, 28 of 186 patients in the highest-intake group developed AD, vs. 54 of 182 in the lowest-intake group.

With respect to individual flavonols, kaempferol intake was linked to a reduction of almost 50%, and both myricetin and isorhamnetin by 40% each. A fourth flavonol, called quercetin, had no noticeable effect on AD risk.

Participants with the highest flavonol intake drank about one cup of black tea a day. Kale, and about a glass of red wine each day, could also supply flavonols.

Sources of flavonols

Kaempferol is richly present in green leafy vegetables, including spinach, broccoli, beans, tea and kale – and also in tea. Isorhamnetin-rich foods include olive oil, red wine, pears and tomato sauce. Myricetin is found in tea, kale, oranges, tomatoes and red wine.

Researcher Thomas Holland says, “More research is needed to confirm these results, but these are promising findings. Eating more fruits and vegetables and drinking more tea could be a fairly inexpensive and easy way for people to help stave off Alzheimer's dementia.”

Implications

Many scientists disagree with the emphasis on flavonols. Though these were thought to have antioxidant activity in the body, this theory was discredited many decades earlier. Antioxidant activity ceases when they are ingested and subjected to the activity of enzymes in the digestive tract.

They point out that flavonols are found in many plants, fruits and vegetables, which have been associated with good health for centuries. Nutritionists say that the AD-delaying effects of such foods are likely due to other plant chemicals which are relatively more abundant. On the other hand, taking flavonol pills or tea extracts is unlikely to produce the same healthful effect, and overdoses could be counterproductive.

This is not to say that eating more flavonol-rich foods or drinking a cup of black tea in the morning would hurt, since any foods containing these chemicals would also contain many more healthful compounds including vitamins, minerals and plant fiber. Holland makes a valid point with his conclusion: “'With the elderly population increasing worldwide, any decrease in the number of people with this devastating disease, or even delaying it for a few years, could have an enormous benefit on public health.”

https://n.neurology.org/content/early/2020/01/29/WNL.0000000000008981

Plant flavonols significantly reduce Alzheimer’s risk

Matcha green tea kills breast cancer stem cells

MATCHA, the Green Tea packed with antioxidants, is often hailed as containing properties which prevent disease.

Scientists in Salford, UK have shed a ray of light on the claim by testing it on cancer stem cells - with surprising results.

In research published in the journal Aging, a team from the Biomedical Research Centre at the University of Salford, used metabolic phenotyping on cell lines of breast cancer stem cells and found that Matcha "shifted cancer cells towards a quiescent metabolic state" and stopped their spread at a relatively low concentration (0.2 mg/ml).

They also found that the signaling pathways that promote cancer stem cells indicated that Matcha "strongly affected mTOR signals, weakening components of the 40S ribosome. This raised the possibility that Matcha could be used in place of chemical drugs such as rapamycin.

Michael Lisanti, professor of translational medicine at the center, explained: "Matcha green tea is a natural product used as a dietary supplement with great potential for a range of treatments. But, the molecular mechanism underpinning all that remains largely unknown.

"By using metabolic phenotyping, we found that the tea is suppressing oxidative mitochondrial metabolism - in other words it is preventing the cells from 're-fuelling' and therefore they become inactive and die.

"The effects on human breast cancer cells were very striking; the active ingredients in matcha having a surgical effect in knocking out certain signaling pathways.

"Our results are consistent with the idea that Matcha may have significant therapeutic potential, mediating the metabolic reprogramming of cancer cells."

The team who specialize in identifying non-toxic methods of killing cancer stem cells recently found that Earl Grey tea ingredient, Bergamot kills cancer cells and works as an anti-cholesterol agent.

Ref : https://www.salford.ac.uk/news/articles/2018/green-tea-prevent-cancer-cells-from-refuelling

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

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...  

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

 

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.

 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."

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

Study: Antioxidant flavonol linked to lower risk of Alzheimer's dementia

In continuation of my update on kaempferol, myricetin and  quercetin

 

                                                                 kaempferol

                                                                       

                                                                      myricetin

                                                 

                                                                          Quercetin

        

People who eat or drink more foods with the antioxidant flavonol, which is found in nearly all fruits and vegetables as well as tea, may be less likely to develop Alzheimer's dementia years later, according to a study published in the January 29, 2020, online issue of Neurology, the medical journal of the American Academy of Neurology.

"More research is needed to confirm these results, but these are promising findings," said study author Thomas M. Holland, MD, of Rush University in Chicago. "Eating more fruits and vegetables and drinking more tea could be a fairly inexpensive and easy way for people to help stave off Alzheimer's dementia. With the elderly population increasing worldwide, any decrease in the number of people with this devastating disease, or even delaying it for a few years, could have an enormous benefit on public health."

Flavonols are a type of flavonoid, a group of phytochemicals found in plant pigments known for its beneficial effects on health.

The study involved 921 people with an average age of 81 who did not have Alzheimer's dementia. The people filled out a questionnaire each year on how often they ate certain foods. They were also asked about other factors, such as their level of education, how much time they spent doing physical activities and how much time they spent doing mentally engaging activities such as reading and playing games.

The people were tested yearly to see if they had developed Alzheimer's dementia. They were followed for an average of six years. The researchers used various tests to determine that 220 people developed Alzheimer's dementia during the study.

The people were divided into five groups based on how much flavonol they had in their diet. The average amount of flavonol intake in US adults is about 16 to 20 milligrams per day. In the study, the lowest group had intake of about 5.3 mg per day and the highest group consumed an average of 15.3 mg per day.

The study found that people in the highest group were 48 percent less likely to later develop Alzheimer's dementia than the people in the lowest group after adjusting for genetic predisposition and demographic and lifestyle factors. Of the 186 people in the highest group, 28 people, or 15 percent, developed Alzheimer's dementia, compared to 54 people, or 30 percent, of the 182 people in the lowest group.

The results were the same after researchers adjusted for other factors that could affect the risk of Alzheimer's dementia, such as, diabetes, previous heart attack, stroke and high blood pressure.

The study also broke the flavonols down into four types: isorhamnetin, kaempferol, myricetin and quercetin. The top food contributors for each category were: pears, olive oil, wine and tomato sauce for isorhamnetin; kale, beans, tea, spinach and broccoli for kaempferol; tea, wine, kale, oranges and tomatoes for myricetin; and tomatoes, kale, apples and tea for quercetin.

People who had high intake of isorhamnetin were 38 percent less likely to develop Alzheimer's. Those with high intake of kaempferol were 51 percent less likely to develop dementia. And those with high intake of myricetin were also 38 percent less likely to develop dementia. Quercetin was not tied to a lower risk of Alzheimer's dementia.

Holland noted that the study shows an association between dietary flavonols and Alzheimer's risk but does not prove that flavonols directly cause a reduction in disease risk.

Other limitations of the study are that the food frequency questionnaire, although valid, was self-reported, so people may not accurately remember what they eat, and the majority of participants were white people, so the results may not reflect the general population.

https://en.wikipedia.org/wiki/Myricetin

https://en.wikipedia.org/wiki/Quercetin

https://medicalxpress.com/news/2019-07-high-hemoglobin-linked-dementia.html