Posts Tagged ‘Aging’

MECHANISM DISCOVERED FOR HEALTH BENEFIT OF GREEN TEA

Thursday, June 2nd, 2011

One of the beneficial compounds found in green tea has a powerful ability to increase the number of “regulatory T cells” that play a key role in immune function and suppression of autoimmune disease, according to new research in the Linus Pauling Institute at Oregon State University. This may be one of the underlying mechanisms for the health benefits of green tea, which has attracted wide interest for its ability to help control inflammation, improve immune function and prevent cancer.

Emily Ho
Emily Ho
Associate Professor
Principal Investigator
Linus Pauling Institute
Photo: oregonstate.edu

Pharmaceutical drugs are available that perform similar roles and have been the subject of much research, scientists say, but they have problems with toxicity. A natural food product might provide a long term, sustainable way to accomplish this same goal without toxicity, researchers said.

“This appears to be a natural, plant-derived compound that can affect the number of regulatory T cells, and in the process improve immune function,” said Emily Ho, an LPI principal investigator and associate professor in the OSU Department of Nutrition and Exercise Sciences.

“When fully understood, this could provide an easy and safe way to help control autoimmune problems and address various diseases,” Ho said.

The findings have been published in Immunology Letters, a professional journal.

There are many types of cells that have different roles in the immune system, which is a delicate balancing act of attacking unwanted invaders without damaging normal cells. In autoimmune diseases, which can range from simple allergies to juvenile diabetes or even terminal conditions such as Lou Gehrig’s disease, this process goes awry and the body mistakenly attacks itself.

Some cells exist primarily to help control that problem and dampen or “turn off” the immune system, including regulatory T cells. The number and proper function of those regulatory T cells, in turn, is regulated by other biological processes such as transcription factors and DNA methylation.

In this study, OSU scientists did experiments with a compound in green tea, a polyphenol called EGCG, which is believed to be responsible for much of its health benefits and has both anti-inflammatory and anticancer characteristics. They found it could cause a higher production of regulatory T cells. Its effects were not as potent as some of those produced by prescription drugs, but it also had few concerns about long-term use or toxicity.

“EGCG may have health benefits through an epigenetic mechanism, meaning we aren’t changing the underlying DNA codes, but just influencing what gets expressed, what cells get turned on,” Ho said. “And we may be able to do this with a simple, whole-food approach.”

Laboratory studies done with mice, Ho said, showed that treatment with EGCG significantly increased the numbers and frequencies of regulatory T cells found in spleen and lymph notes, and in the process helped to control the immune response.

“Epigenetic regulation can be potentially exploited in generating suppressive regulatory T cells for therapeutic purposes, and is of significant clinical importance for the suppression of autoimmune diseases,” the researchers said in their study.

The research was done by scientists from OSU, the University of Connecticut, and Changwon National University in South Korea. The work was supported by the National Institute of Environmental Health Sciences and the Oregon Agricultural Experiment Station.

>>>>>Read more in our HeartVigor.com Green Tea Page.

TAI CHI FIGHTS DEPRESSION IN ELDERLY

Wednesday, March 16th, 2011

Los Angeles, CA

The numbers are, well, depressing: More than 2 million people age 65 and older suffer from depression, including 50 percent of those living in nursing homes. The suicide rate among white men over 85 is the highest in the country - six times the national rate.

Dr. Helen Lavretsky
Dr. Helen Lavretsky
UCLA professor
in residence
of psychiatry
Photo: ucla.edu

And we’re not getting any younger. In the next 35 years, the number of Americans over 65 will double and the number of those over 85 will triple.

So the question becomes, how to help elderly depressed individuals?

Researchers at UCLA turned to a gentle, Westernized version of tai chi chih, a 2,000 year old Chinese martial art. When they combined a weekly tai chi exercise class with a standard depression treatment for a group of depressed elderly adults, they found greater improvement in the level of depression - along with improved quality of life, better memory and cognition, and more overall energy - than among a different group in which the standard treatment was paired with a weekly health education class.

The results of the study appear in the current online edition of the American Journal of Geriatric Psychiatry.

“This is the first study to demonstrate the benefits of tai chi in the management of late life depression, and we were encouraged by the results,” said first author Dr. Helen Lavretsky, a UCLA professor in residence of psychiatry. “We know that nearly two thirds of elderly patients who seek treatment for their depression fail to achieve relief with a prescribed medication.”

In the study, 112 adults age 60 or older with major depression were treated with the drug escitalopram, a standard antidepressant, for approximately four weeks. From among those participants, 73 who showed only partial improvement continued to receive the medication daily but were also randomly assigned to 10 weeks of either a tai chi class for two hours per week or a health education class for two hours per week.

All the participants were evaluated for their levels of depression, anxiety, resilience, health related quality of life, cognition and immune system inflammation at the beginning of the study and again four months later.

The level of depression among each participant was assessed using a common diagnostic tool known as the Hamilton Rating Scale for Depression, which involves interviewing the individual. The questions are designed to gauge the severity of depression. A cut off score of 10/11 is generally regarded as appropriate for the diagnosis of depression.

The researchers found that among the tai chi participants, 94 percent achieved a score of less than 10, with 65 percent achieving remission (a score of 6 or less). By comparison, among participants who received health education, 77 percent achieved scores of 10 or less, with 51 percent achieving remission.

While both groups showed improvement in the severity of depression, said Lavretsky, who directs UCLA’s Late Life Depression, Stress and Wellness Research Program, greater reductions were seen among those taking escitalopram and participating in tai chi, a form of exercise that is gentle enough for the elderly.

“Depression can lead to serious consequences, including greater morbidity, disability, mortality and increased cost of care,” Lavretsky said. “This study shows that adding a mind body exercise like tai chi that is widely available in the community can improve the outcomes of treating depression in older adults, who may also have other, coexisting medical conditions, or cognitive impairment.

“With tai chi,” she said, “we may be able to treat these conditions without exposing them to additional medications.”

>>>>>Read more on aging in our HeartVigor.com Aging Page.

>>>>>Read more in our HeartVigor.com News Page.