Nov 052010

A protein produced in cases of rheumatoid arthritis appears to protect against the development of Alzheimer’s disease, US scientists have said.

In the Journal of Alzheimer’s Research study, mice with memory loss given the protein fared better in tests.

A synthetic version of GM-CSF protein is already used as a cancer treatment.

UK experts said the study was “an important first step” and tests were needed to see if the drug worked for people with Alzheimer’s.

In people with rheumatoid arthritis, the immune system goes into “overdrive” and produces attacking proteins – including GM-CSF.

Rubbish collectors

It had already been recognised that people with rheumatoid arthritis were less likely to develop Alzheimer’s, but the protective link had been thought to be due to non-steroidal anti-inflammatory drugs (NSAIDs) taken by people with the condition.

However tests showed this was not the case.

In this study, University of South Florida researchers genetically altered mice to have memory problems similar to those seen in Alzheimer’s disease, which is a form of dementia.

They then treated them – and some healthy mice – with the protein. Other mice – both healthy ones and those with Alzheimer’s symptoms – were given a dummy (placebo) treatment.

Positive results in mice can be an important first step for any new treatment”

End Quote Dr Simon Ridley Alzheimer’s Research Trust

At the end of the 20-day study, the Alzheimer’s mice treated with GM-CSF fared substantially better on tests measuring memory and learning, and performed at a similar level to mice of the same age without the condition.

Even the healthy mice treated with GM-CSF performed slightly better than their untreated peers.

Mice with Alzheimer’s that were given the placebo continued to do poorly in the tests.

The researchers have suggested the protein may attract an influx of cells called microglia from the peripheral blood supply around the brain, which then attack the characteristic plaques that form in people with Alzheimer’s.

Microglia are like the body’s natural “rubbish collectors” that go to damaged or inflamed areas to get rid of toxic substances.

The brains of GM-CSF-treated Alzheimer’s mice showed more than a 50% decrease in beta amyloid, the substance which forms Alzheimer’s plaques.

The researchers also observed an apparent increase in nerve cell connections in the brains of the GM-CSF-treated mice, which they say could be a reason memory decline was reversed.

‘Crucial next stage’

Dr Huntington Potter, who led the research at the University of South Florida’s Health Byrd Alzheimer’s Institute, said: “Our findings provide a compelling explanation for why rheumatoid arthritis is a negative risk factor for Alzheimer’s disease.”

An artificial version of GM-CSF, a drug called Leukine, is already approved by the US Food and Drug Administration and has been used to treat cancer patients who need to generate more immune cells.

Dr Potter added. “Our study, along with the drug’s track record for safety, suggests Leukine should be tested in humans as a potential treatment for Alzheimer’s disease.”

Dr Simon Ridley, head of research at the UK’s Alzheimer’s Research Trust, said: “Positive results in mice can be an important first step for any new treatment, and it’s encouraging the team is already planning the crucial next stage of a trial in people.

“We won’t know whether GM-CSF can help people with Alzheimer’s until clinical trials are completed”.

Dr Susanne Sorensen, head of research at the Alzheimer’s Society, said: “This exciting research provides a possible answer to the long, unexplained question of why rheumatoid arthritis could reduce the risk of Alzheimer’s disease.

“Given the identified protein is already available as a drug that is proven to be safe in humans, the time taken to develop an Alzheimer’s disease treatment could be substantially reduced.

“However, we must not jump the gun. Much more research is needed before we can say for certain that the findings demonstrated in mice would also occur in humans.”

Nov 052010

Practicing yoga may do more than calm the mind — it may help protect against certain diseases, a new study suggests.

In the study, women who had practiced yoga regularly for at least two years were found to have lower levels of Inflammation is an immune response and can be beneficial when your body is fighting off infection, but chronically high levels of inflammation are known to play a role in certain conditions, including asthma, cardiovascular disease and depression.

Inflammation is known to be boosted by stressful situations. But when yoga experts were exposed to stress (such as dipping their feet in ice water,) they experienced less of an increase in their inflammatory response than yoga novices did.

“The study is the first one, I think, to really suggest how yoga could have some distinctive
benefits in terms of the immune system,” said researcher Janice Kiecolt-Glaser of Ohio State University. “It suggests that regular yoga practice is really good for you.” she told LiveScience.

Stressed Out

Kiecolt-Glaser and her Ohio State colleagues recruited 50 women between the ages of 30 and 65 and with different degrees of yoga experience. Those labeled “yoga experts” had practiced yoga once or twice a week for at least two years, while “yoga novices” had participated in only six to 12 sessions. (The researchers wanted novices to have at least some experience so that they wouldn’t be stressed out simply from having to practice yoga for the first time.)

The two groups were very similar in terms of age, physical fitness level and amount of body fat. This was important because all three of these factors are known to influence inflammation. Participants completed three stressful tasks in succession. In one, subjects immersed a foot in warm water and then in ice water for one minute. In another, they had to perform tricky mental arithmetic for five minutes.

Then subjects either completed a yoga session or took part in one of two control experiments, which involved walking on a treadmill, or watching a video.

All the while, subjects had catheters placed in their arms to collect blood samples periodically. The researchers examined the blood samples for key markers of inflammation, one of which is a protein called IL-6.

Across all the tasks and other experimental scenarios, the novices’ IL-6 levels were 41 percent higher than the experts’. The novices also produced more IL-6 in response to the stressful tasks.

Breath Control

While the researchers aren’t sure why yoga would have this effect on inflammation, they have a few speculations.

Yoga focuses on deep breathing and controlling breathing, which may slow down the body’s “fight or flight” response — the body’s reaction to stress, Kiecolt-Glaser said.

Yoga also involves meditation, which helps people learn to pay attention to how they are feeling. So yoga experts may be more aware of their stress and better able to control their response to it.

Finally, yoga is a form of exercise, which is known to decrease inflammation.

A randomized clinical trial will be needed to confirm the findings, Kiecolt-Glaser said. Such a trial would involve randomly assigning participants to either practice yoga or refrain from it over a certain time frame. Researchers would then look to see whether the activity had any effect on inflammation.

The study was published in the January issue of the journal Psychosomatic Medicine. Kiecolt-Glaser also discussed her study at the 118th annual
of the American Psychological Association, which was held Aug. 11 to Aug. 14 in San Diego.

Nov 052010

World Cancer Research Fund says even moderate exercise such as brisk walking can reduce risk of cancer

About 10,000 Britons a year could avoid getting breast or bowel cancer if they undertook more physical activity, especially walking, according to the World Cancer Research Fund.

Some 5,500 women would not develop breast cancer if they were moderately active for at least 45 minutes a day, experts say. There would also be an estimated 4,600 fewer cases of bowel cancer if more people took more exercise.The WCRF stress that, to prove beneficial, the activity only needs to make someone’s heart beat faster. It recommends that everyone does at least half an hour of such exercise daily.

Dr Rachel Thompson, deputy head of science for WCRF, said: “There is very strong evidence that being physically active is important for cancer prevention.

“You can reduce your cancer risk just by making small changes and this is highlighted by the fact that so many cancer cases could be prevented through something as simple as brisk walking.

“By taking up walking as a hobby or even walking to the shops instead of taking the bus or car, people can make a real difference to their health.”

Nov 052010

Scientists at Northumbria University say they have carried out the first rigorous scientific analysis of dance moves that make men attractive to women.

Writing in the Royal Society Journal, Biology Letters, the researchers believe that movements associated with good dancing are also indicative of good health and reproductive potential.

Dr Nick Neave asked young men, who were not professional dancers, to dance in a laboratory to a very basic drum rhythm and filmed their movements with 12 cameras.

The dancing was then converted into computer-generated cartoons – which women rated on a scale of 1 to 7.

This video shows examples of “good” dancing and “bad” dancing.

Nov 052010

Stress increases the chances of dying from heart-related problems by five-fold, a study has found

Researchers have found that people aged 65 or older were five times more likely to die within the six year follow-up period if they had high levels of stress hormones.

They were more likely to die from cardiovascular disease, such as heart attacks, heart failure and strokes, but not more likely to die from other causes such as cancer, it was found.

Short-term stress is thought to be good for health but chronic long-term stress can lead to damage in the lining of the blood vessels.

Stress can also raise blood pressure and cholesterol which are known to be harmful to the heart and stressed people tend to eat a poorer diet and may be more likely to smoke.

Researchers at VU University Medical Center in The Netherlands, measured levels of the stress hormone, cortisol, in the urine of 861 people aged 65 or older. The measurement was taken once over a 24-hour period.

They were then tracked for six years and any deaths recorded.

It was found that those with the highest levels of cortisol in their urine were five times more likely to die of cardiovascular disease than those with the lowest levels.

They took into account other factors that could influence cardiovascular disease, such as socio-economic status, health problems such as obesity and high blood pressure and lifestyle factors such as smoking

The findings are due to be published in the Journal of Clinical Endocrinology & Metabolism.

Dr Nicole Vogelzangs, lead author of the study, said: “Previous studies have suggested that cortisol might increase the risk of cardiovascular mortality, but until now, no study had directly tested this hypothesis.

“The results of our study clearly show that cortisol levels in a general older population predict cardiovascular death, but not other causes of mortality.

“Cortisol is an important component of the stress system of the human body but in higher concentrations can be harmful.

“Our study shows that older persons with high levels of cortisol have an increased risk of dying from cardiovascular disease. This finding significantly adds evidence to the belief that cortisol can be damaging to the cardiovascular system.”

One in three of all deaths in Britain are caused by cardiovascular disease, accounting for more than 200,000 deaths per year.

Ellen Mason, Senior Cardiac Nurse at the British Heart Foundation, said: “Stress is already associated with an increased risk of heart disease and this study throws up more evidence about the role of cortisol.

“However, there are other chemicals in our body besides cortisol which play a part when we’re stressed out. So although this study helps, there is still a lot left to learn.

“It’s important we all try and find ways to cope with stress which don’t involve unhealthy habits that increase your risk of heart disease, such as smoking, drinking too much alcohol and eating foods high in saturated fat and salt.”