This Month:
- Anti-Cancer Compound in G. Tea Identified
- Green Tea May Fight Lung Cancer
- COX-2 Inhibitors Slow Prostate Cancer
- Green Tea Can Help Ward Off Skin Cancer
- Green Tea May Prevent HIV Infection
- Green and Jasmine Tea Kill Deadly Bacteria
- Green Tea for the Skin
- Professor testing tea benefits

Spanish and British scientists have discovered how green tea helps to prevent certain types of cancer.
Researchers at the University of Murcia in Spain (UMU) and the John Innes Center (JIC) in Norwich, England have shown that a compound called EGCG in green tea prevents cancer cells from growing by binding to a specific enzyme.

"We have shown for the first time that EGCG, which is present in green tea at relatively high concentrations, inhibits the enzyme dihydrofolate reductase (DHFR), which is a recognized, established target for anti-cancer drugs, " says Professor Roger Thorneley, of JIC.

"This is the first time, to our knowledge, a known target for an anti-cancer drug has been identified as being inhibited by EGCG," he added.

Green tea has about five times as much EGCG as regular tea, studies have shown. It decreased rates of certain cancers but scientists were not sure what compounds were involved or how they worked. Nor had they determined how much green tea a person would have to drink to have a beneficial effect, he said.

Thorneley said EGCG is probably just one of a number of anti-cancer mechanisms in green tea.

"We have identified this enzyme in tumour cells that EGCG targets and understand how it stops this enzyme from making DNA. This means we may be able to develop new anti-cancer drugs based on the structure of the EGCG molecule," Thorneley explained.

The scientists decided to look at ECGC after they realized its structure was similar to a cancer drug called methotrexate.

"We discovered that EGCG can kill cancer cells in the same way as methotrexate," Dr Jose Neptuno Rodriguez-Lopez, of UMU, a joint author of the research published in the journal Cancer Research.

EGCG binds strongly to DHFR, which is essential in both healthy and cancerous cells. But it does not bind as tightly as methotrexate, so its side effects on healthy cells could be less severe than those of the drug.

Thorneley said EGCG could be a lead compound for new anti-cancer drugs. The findings could also explain why women who drink large amounts of green tea around the time they conceive and early in their pregnancy may have an increased risk of having a child with spina bifida or other neural tube disorders. Women are advised to take supplements of folic acid because it protects against spina bifida.

But large amounts of green tea could decrease the effectiveness of folic acid. "This enzyme, (DHFR), is the one folic acid supplements are given for. Folic acid deficiency leads to neural tube development defects," Thorneley added.

REFERENCE:
http://paktribune.com/news/index.shtml?172379

Green tea may fight lung cancer and could inspire the creation of new lung cancer drugs, scientists report.

But it may be too soon to count on a cup of green tea to curb lung cancer. So far, the scientists have only tested green tea extract against human lung cancer cells in test tubes, not people.

The researchers included Qing-Yi Lu, PhD, of the Center for Human Nutrition at the University of California at Los Angeles (UCLA).

Lu and colleagues exposed a sample of human lung cancer cells to a decaffeinated green tea extract. The lung cancer cells marinated in the green tea extract for up to three days.

The green tea extract remodeled a certain protein in the lung cancer cells. As a result, the lung cancer cells became more likely to stick together and less likely to move, the study shows.

Antioxidants in green tea may have tweaked the cancer cell protein, but it's not clear whether one antioxidant deserves all the credit or whether several antioxidants worked together, the researchers note.

The study doesn’t prove that drinking green tea curbs lung cancer in people.

However, it may be possible to make new lung cancer drugs based on green tea extract, Lu's team suggests. Such drugs would target the lung cancer protein remodeled by the green tea extract in the lab tests.

REFERENCE:
http://www.webmd.com/lung-cancer/news/20070312/green-tea-may-fight-lung-cancer

The study appears online in Laboratory Investigation.
SOURCES: Lu, Q. Laboratory Investigation, March 12, 2007; online edition. News release, Laboratory Investigation.

PHILADELPHIA -- Drinking a nice warm cup of green tea has long been touted for its healthful benefits, both real and anecdotal. But now researchers have found that a component of green tea, combined with low doses of a COX-2 inhibitor, could slow the spread of human prostate cancer.

In the March 1 issue of Clinical Cancer Research, researchers from University of Wisconsin-Madison demonstrate that low doses of the COX-2 inhibitor celecoxib, administered with a green tea polyphenol called pigallocatechin-3-gallate (EGCG), can slow the growth of human prostate cancer. Their experiments were performed in cell cultures and in a mouse model for the disease.

"Celecoxib and green tea have a synergistic effect -- each triggering cellular pathways that, combined, are more powerful than either agent alone," said Hasan Mukhtar, Ph.D., professor of dermatology at the University of Wisconsin and member of Wisconsin's Paul Carbone Comprehensive Cancer Center. "We hope that a clinical trial could lead to a preventative treatment as simple as tea time."

Previous research has linked the cyclooxygenase-2 enzyme, commonly known as COX-2, to many cancer types, including prostate cancer, said Mukhtar. Mukhtar and his colleagues have previously shown COX-2 inhibitors like celecoxib (known under the brand name Celebrex™) suppress prostate cancer in animal models. COX-2 inhibitors also have been shown to cause adverse cardiovascular effects when administered at high doses over long durations.

In 2004, Mukhtar and his colleagues demonstrated that green tea polyphenol EGCG has cancer-fighting abilities of its own. Their study, published in Cancer Research, showed that EGCG can modulate the insulin-like growth factor-1 (IGF-1)-driven molecular pathway in a mouse model for human prostate cancer, pushing the cells toward programmed cell death (apoptosis).

"We believed that COX-2 inhibitors may still prove beneficial if used in combination with complementary agents," Mukhtar said. "Our studies showed that the additive effect of green tea enables us to utilize the cancer-fighting abilities of COX-2 inhibitors, but at lower, safer doses."

In this latest research, Mukhtar and his colleagues looked at the effects of the two substances on cultured human prostate cancer cells. Alone, both EGCG and NS-398, a COX-2 inhibitor similar to celecoxib, demonstrated the ability to slow cancer cell growth and limit the presence of known cancer-promoting proteins within the cell samples. Together, EGCG and NS-398 suppressed cell growth by an additional 15 to 28 percent.

The researchers repeated the experiment in mouse models of prostate cancer, using celecoxib and an oral suspension of the decaffeinated green tea polyphenol. By using pharmacy-grade celecoxib and actual tea, they had hoped to replicate real-life conditions. "The idea is that it would be easier to get people to drink green tea than it would be to take an additional dietary supplement," Mukhtar said.

In mice that were not treated with either substance, the tumor volume averaged 1,300 cubic millimeters, whereas mice given either the tea or celecoxib had tumors averaging 835 cubic millimeters and 650 cubic millimeters, respectively. Tumors taken from mice given both agents, however, measured on average a volume of 350 cubic millimeters.

In parallel to tumor growth inhibition, mice that received a combination of green tea and celecoxib registered a greater decrease in prostate specific antigen (PSA) levels compared to that in celecoxib alone or green tea alone treated animals. PSA is a protein produced by the cells of the prostate and is used as a marker for detection and progression of prostate cancer. These results, combined with a marked decrease in the presence of cancer-promoting proteins, offered clear indications that green tea and celecoxib, combined, could be useful in slowing prostate cancer growth, Mukhtar said.

"Prostate cancer typically arises from more than one defect in the cellular mechanics, which means that a single therapeutic might not work fighting a particular cancer long-term," Mukhtar said. "If tests in human trials replicate these results, we could see a powerful combined therapy that is both simple to administer and relatively cost effective."

The study was funded by the National Cancer Institute.

The mission of the American Association for Cancer Research is to prevent and cure cancer, and is the world's oldest and largest professional organization dedicated to advancing cancer research.

The American Cancer Society estimated that 2006 would bring with it 1 million new diagnoses of skin cancer in the United States – a number that could have been reduced by people limiting their exposure to the sun's harmful ultraviolet rays.

But not everyone can avoid the risk. Many people have jobs that keep them outside most of the day, and even those who have limited exposure to the sun's rays are at risk.

Santosh Katiyar, Ph.D., an associate professor in dermatology, has been studying ways for humans to protect themselves from skin cancer for 16 years, including the past six years here at UAB.

He says the answer is found in green tea.

Katiyar is convinced that the rich polyphenol content found in green tea is the most potent tumor-inhibitor found in nature. His studies show that an antioxidant called epigallocatechin-3-gallae (EGCG), which is found in green tea, appears to protect the skin from ultraviolet radiation-induced damage and prevent skin tumor formation.

"I've found that green tea, whether applied topically or taken orally, is certainly beneficial in the area of cancer prevention, at least in laboratory animal models," Katiyar says. "Green tea prevents UV radiation-induced suppression of the immune system, which has been considered as a risk factor for the development of skin cancer."

Common beverage
Skin is the largest organ of the body and the first defense barrier for the body from external physical, chemical and environmental pollutants, including solar ultraviolet radiation.

According to the American Cancer Society, more than 1 million cases of basal cell or squamous cell cancers occur annually. Skin cancer is associated with the epidermal layer and its cell types.

Exposure to UV radiation is the key factor in the initiation of skin disorders, such as wrinkling, scaling, dryness, mottled pigment abnormalities consisting of hypopigmentation and hyperpigmentation and skin cancers. The solar UV light that penetrates the skin's top layer often strikes DNA molecules in the chromosomes, causing harmful mutations which leads to initiation of skin cancer.

Where does green tea fit in? Next to water, tea is the most commonly consumed beverage worldwide because of its characteristic aroma, flavor and health benefits. Of total tea consumption, approximately 78 percent is consumed as black tea, mainly in Western and some Asian countries. Some 20 percent is consumed as green tea, primarily in Asian countries.

Katiyar recently had articles published in Cancer Research and Clinical Cancer Research that stated EGCG prevents UV-induced skin cancer in mice through the enhancement of an immunoregulatory cytokine interleukin-12-dependent DNA-repair device

"The interleukin-12 molecule has the ability to repair UV-induced DNA damage," Katiyar says. "The polyphenols in green tea have strong antioxidant and anti-inflammatory properties, but they enhance the production of interleukin-12. And if the interleukin-12 can play a role in DNA repair, then they can prevent skin cancer."

In addition to the tea, several green tea-based cream products also are available for purchase over the counter. The U.S. Food and Drug Administration says there is not enough evidence to support claims that green tea – whether used topically or consumed in a beverage – prevents or reduces the risk of any type of cancer, but Katiyar hopes more clinical studies with adequate controls such as race, diet and frequency of tea consumption will show green tea's positive effects.

Cancer hits home
Katiyar, who came to the United States from India 16 years ago with a Ph.D. in biochemistry, is like many people when it comes to cancer: He knows the effect the disease can have on people's lives. He lost his mother to breast cancer in 1983.

"My parents spent lots of time, energy and money on my education, a very good education, but I could do nothing to help my mother in her struggle to breast cancer," Katiyar says. "That's when I decided I wanted to do cancer chemoprevention research.

"I know there are still millions of other mothers out there who need protecting."

He says green tea is one way to do just that. Katiyar says green tea purchased in Asian markets is likely to be the highest quality of tea to drink. He suggests five to six cups of green tea a day would be beneficial to those at especially high risk, such as people with fairer skin.

Preparation of the tea is a key, he says. Boil the water and steep approximately one gram of green tea leaves, covered, for four or five minutes before drinking. He says that in that amount of time the polyphenols will dissolve in the warm water. Do not boil the water with the leaves in it, he says, or the polyphenols will not be as active.

"It's crucial that people consume the tea on a regular basis to achieve the maximum benefits," Katiyar says. "Constant, regular consumption will be helpful in preventing skin cancer."

REFERENCE FOR FULL ARTICLE SEE:
http://www.emaxhealth.com/101/10039.html

US and UK joint study suggests that drinking green tea may help to prevent HIV infection.

The preliminary study is published in the Journal of Allergy and Clinical Immunology and was a joint project between the University of Sheffield, UK, and Baylor College of Medicine, in Texas, USA.

The research team did test tube experiments on a green tea flavonoid called epigallocatechin gallate (EGCG) and showed that it binds with CD4 immune system T-cell receptors and stops HIV from doing the same.

One of the researchers, Professor Mike Williamson of the Department of Molecular Biology and Biotechnology at the University of Sheffield said, ""Our research shows that drinking green tea could reduce the risk of becoming infected by HIV, and could also slow down the spread of HIV."

Before people jump to conclusions that this study suggests green tea could deny HIV a foothold in the immune system, critics are cautious and say it is very early days.

Compounds that show good results at the "micro" level of cells in a test tube do not necessarily have the same effect at the "macro" level of immune systems in living organisms.

Prof Williamson was keen to point out that green tea is not a cure, and neither is it a safe way to avoid infection. The study merely suggests that EGCG " has potential use as adjunctive therapy in HIV-1 infection".

In other words, Prof Williamson said, "it should be used in combination with conventional medicines to improve quality of life for those infected".

He also mentioned that further studies to find out how much effect different amounts of green tea might have are already under way.

The study was sponsored by the US National Institutes of Health, and a range of research, education and other funds.

Last September, a study from Japan was published in the Journal of the American Medical Association (JAMA) that reported high consumption of green tea was linked to reduced overall risk of death due to all causes and cardiovascular disease.

Other studies have also found positive links between green tea consumption and cancer.

"Epigallocatechin gallate, the main polyphenol in green tea, binds to the T-cell receptor, CD4: Potential for HIV-1 therapy."

REFERENCE FOR FULL ARTICLE SEE:
http://www.medicalnewstoday.com/healthnews.php
?newsid=66540

Williamson MP, McCormick TG, Nance CL, Shearer WT.
The Journal of Allergy and Clinical Immunology, December 2006 (Vol. 118, Issue 6, Pages 1369-1374).

Take a serving of extracts from green tea or Jasmine tea, mix in some wildflower dark honey and you have something more useful than a drink. It’s actually a scientific mixture that can be used to reduce pathogenic bacteria in meats.

Take a serving of extracts from green tea or Jasmine tea, mix in some wildflower dark honey and you have something more useful than a drink. It’s actually a scientific mixture that can be used to reduce pathogenic bacteria in meats.

“Our results indicated that Jasmine tea with honey and green tea with honey had the highest antimicrobial activity,” said Daniel Fung, the Kansas State University food science professor who supervised the research for the Food Safety Consortium.

The tests were first conducted in a liquid medium and found that the tea extract and honey treatments caused significant reductions of Listeria monocytogenes and E. coli O157:H7 bacteria. “That’s not surprising,” Fung said. “In liquid medium, it’s easier for the compounds to interact with the organisms in liquid.”

Then Fung, working with KSU researchers Beth Ann Crozier-Dodson and Laura Munson, moved on to food, which can be a more difficult medium when seeking to cause the type of reaction among the compounds that will inhibit pathogens.

The results were good. Treating turkey breast slice with combinations of Jasmine tea extract and wildflower dark honey reduced Listeria monocytogenes by 10 to 20 percent. Similar reductions of the pathogen were recorded when applied to hot dogs.

The most successful reductions in hot dogs were in those that had been commercially treated with sodium lactate, potassium lactate and sodium diacetate. “In that type of hot dogs, it has much more suppressive effect than in some of the hot dogs without those compounds,” Fung explained. “There is a synergistic effect of the tea and honey along with those compounds with lactate already in the hot dog.”

One of the beneficial side effects of the treatment is shelf life. Fung noted that the experiments showed the hot dogs were still showing reduced levels of pathogens 14 days after the application.

With such favorable results from the tests, Fung is thinking ahead to future possible applications as a surface wash for meat during processing as well as way to improve the safety of ready-to eat meats and vegetables.

REFERENCE FOR FULL ARTICLE SEE:
http://toronto.fashion-monitor.com/news.php/restaurants/2007030202Tea-Listeria

(WFRV) SCOTTSDALE, AZ We're All Looking For That One Magic Product That Makes People Say Wow.. When They Look At Our Skin. So What If It Was As Easy As A Little Dose Of Green Tea?

Green Tea for Skin
The New Secret Weapon To Fight Aging.. May Be Found In This Tea Bag. Most Of Us Know Drinking Green Tea Is A Good Thing.. It's Full Of Antioxidants. But New Studies Show Green Tea.. In Its Purest Form.. Can Also Fight The Signs Of Aging.

Dermatologist Miriam Cummings, MD says "Theoretically, Green Tea Is A Panacea. It's A Wonderful Thing For The Skin. It Stops Inflammation; It Stops DNA From Being Damaged. It Stops The Sun From Burning The Skin So In A Perfect World It's The Perfect Thing To Use On Your Skin."

Dr. Miriam Cummings Cautions That Before You Spend A Fortune On These Products.. Make Sure You're Getting What You Pay For. "You Look At The Very Back Of The Product, And See Where Is That Green Tea. Is It At The Very Top, Or Is It In The Middle Or Is It At The Bottom Of The List. If It's At The Very Top And It's The First Ingredient, Then You've Got Mostly Green Tea In That Product."

REFERENCE FOR FULL ARTICLE SEE:
http://wfrv.com/health/local_story_082072342.html

An assistant professor at OSU is conducting a study to determine whether green tea beverages or supplements can reduce body fat and prevent health problems.

Arpita Basu said foods that are high in antioxidants, such as green tea, may prevent or delay the development of diabetes, cancer and other health problems.

Misti Leyva, director of nutritional research at Oklahoma University Health Sciences, said the findings from the research in this study could be expanded and lead to further research of green tea and its benefits.

The study is in Oklahoma City at the University of Oklahoma Health Sciences Center.

The study aims to analyze the effects of green tea beverages versus green tea extracts. It will also determine whether the green tea causes any difference in body fat composition, blood glucose levels or lipid levels among the participants, according to Basu’s research protocol.

Basu is working with Timothy Lyons, program director at OU’s general clinical research center, to conduct the research. The study includes 60 pre-diabetic candidates ranging from 22 to 75 from Oklahoma City. The participants are split into three groups: one drinking four cups of green tea daily, the second group taking the equivalent in green tea supplements and the third consuming no green tea. At the beginning, during and at the end of the eight week study the weight, body fat and blood samples of the participants are taken. The results will be analyzed to determine any significant changes.

Basu said most of the chronic diseases, such as cardiovascular disease, type II diabetes and cancer, are related to high rates of oxidized stress and inflammation

“That is what got me interested in green tea because it is a natural food with high health benefits,” Basu said.

Green tea contains the active ingredient epigallocatechin-3-gallate, commonly known as EGCG. This component is an antioxidant and anti-inflammatory ingredient in green tea. Basu and her graduate assistant, Kara Sanchez, have set up a test in their lab that allows them to measure the amount of EGCG in the green tea beverage and the green tea supplement to assure the two amount are equivalent, Basu said.

She said in her experience, intervention as soon as doctors diagnose a person with metabolic syndrome, when they pre-diabetic, can delay the progression of the metabolic abnormalities.

Misti Leyva, manager of nutritional research at the OU Health Sciences Center, said people tend to look for a quick fix or a miracle supplement.

Green tea will most likely not be a miracle, but it may have some health benefits that would not only improve chances of preventing chronic disease, but also assist with weight loss, Leyva said.

“Things are often taken out of context or presented in a false light, especially when it suggests weight loss,” Leyva said. “That is why we do research, to provide evidence and correct any misconceptions.”

Basu said about 10 percent of Americans drink green tea.

“But since the brand Lipton has developed their line of green tea I have seen many more people drinking it,” Basu said.

A large number of the participants are young, in their 20s, Basu said. This is the age of many college students who are already considered pre-diabetic.

REFERENCE FOR FULL ARTICLE SEE:
http://www.ocolly.com/read_story.php?a_id=32364