An apple a day boosts the immune system

August 30th, 2010

“Soluble fiber changes the personality of immune cells — they go from being pro-inflammatory, angry cells to anti-inflammatory, healing cells that help us recover faster from infection,” said Gregory Freund, a professor in the U of I’s College of Medicine and a faculty member in the College of Agriculture, Consumer and Environmental Sciences” Division of Nutritional Sciences.

This happens because soluble fiber causes increased production of an anti-inflammatory protein called interleukin-4, he said.

The study will appear in the May 2010 issue of Brain, Behavior, and Immunity.
In the experiment, laboratory mice consumed low-fat diets that were identical except that they contained either soluble or insoluble fiber. After six weeks on the diet, the animals had distinctly different responses when the scientists induced illness by introducing a substance (lipopolysaccharide) that causes the body to mimic a bacterial infection.

“Two hours after lipopolysaccharide injection, the mice fed soluble fiber were only half as sick as the other group, and they recovered 50 percent sooner. And the differences between the groups continued to be pronounced all the way out to 24 hours,” said Christina Sherry, who also worked on the study.

“In only six weeks, these animals had profound, positive changes in their immune systems,” she said.

Zen meditation minimises pain

August 28th, 2010

University of Montreal researchers compared the grey matter thickness of 17 Zen meditators and 18 non-meditators and found evidence that practising the centuries-old discipline can reinforce a central part of the brain called the anterior cingulate.

“Through training, Zen meditators appear to thicken certain areas of their cortex and this appears to underlie their lower sensitivity to pain,” lead author Joshua Grant said in a statement.

Building on an earlier study, the researchers measured thermal pain sensitivity by applying a heated plate to the calf of participants.

This was followed by scanning the brains of subjects with structural magnetic resonance imaging (MRI).

The MRI results showed central brain regions that regulate emotion and pain were significantly thicker in meditators compared to non-meditators.

“The often painful posture associated with Zen meditation may lead to thicker cortex and lower pain sensitivity,” Grant opined.

The study was published yesterday in a special issue of the American Psychological Association journal, Emotion.

In the previous study, the researchers recruited Zen meditators with more than 1,000 hours of practice and non-meditators and measured their respective tolerance to pain.

Midday napping can make you smarter

August 26th, 2010

The new research suggests that a biphasic sleep schedule not only refreshes the mind, but can also make you smarter.

On the other hand, the more hours we spend awake, the more sluggish our minds become, according to the findings.

The new findings support previous data from the same research team that pulling an all-nighter – a common practice at college during midterms and finals — decreases the ability to cram in new facts by nearly 40 percent, due to a shutdown of brain regions during sleep deprivation.

“Sleep not only rights the wrong of prolonged wakefulness but, at a neurocognitive level, it moves you beyond where you were before you took a nap,” said Matthew Walker, an assistant professor of psychology at UC Berkeley and the lead investigator of these studies.

In the recent UC Berkeley sleep study, 39 healthy young adults were divided into two groups – nap and no-nap. At noon, all the participants were subjected to a rigorous learning task intended to tax the hippocampus, a region of the brain that helps store fact-based memories. Both groups performed at comparable levels.

At 2 p.m., the nap group took a 90-minute siesta while the no-nap group stayed awake. Later that day, at 6 p.m., participants performed a new round of learning exercises.

The researchers found that those who remained awake throughout the day became worse at learning but those who napped did markedly better and actually improved in their capacity to learn.

These findings reinforce the researchers” hypothesis that sleep is needed to clear the brain’s short-term memory storage and make room for new information, said Walker.

Boredom ‘can kill you’

August 24th, 2010

To reach the conclusion, researchers at University College London looked at data from 7524 civil servants, aged between 35 and 55, interviewed between 1985 and 1988 about their levels of boredom.

They then found out whether they had died by April last year.

Those who reported feeling a great deal of boredom were 37 per cent more likely to have died by the end of the study, the researchers found.

Scientists said that this could be a result of those unhappy with their lives turning to such unhealthy habits as smoking or drinking, which would cut their life expectancy.

“The findings on heart disease show there was sufficient evidence to say there is a link with boredom,” the Courier Mail quoted researcher Martin Shipley, who co-wrote the report, as saying.

The study is to be published in the International Journal of Epidemiology this week.

New discovery may help reduce obesity complications

August 22nd, 2010

According to Dr Suneil Koliwad, Gladstone Institute of Cardiovascular Disease, when individuals become obese from overeating, cells called adipocytes located in the fat tissue
fill up with dietary fats and begin to die. Immune cells called macrophages move out of the blood stream and into this tissue, where they accumulate around dying adipocytes.

As the macrophages work to clear away the dead cells, they are exposed to large amounts of dietary fat that can result in unwanted consequences.

Exposure to saturated fats, in particular, causes the macrophages to enter an inflammatory state. In this state, the macrophages secrete cytokines, such as tumour necrosis factor (TNF) alpha, that encourage the development of insulin resistance, diabetes, and heart disease.

They hope that enhancing the capacity of macrophages to store dietary fats might alter this. The researchers focused their study on an enzyme called DGAT1, which makes triglycerides from dietary fats for storage as cellular energy reserves.

They examined a transgenic strain of mice (aP2-Dgat1) that make large amounts of DGAT1 in both adipocytes and macrophages.

On a high-fat diet, these mice became obese, but the macrophages in their fat tissue did not undergo inflammatory activation, and the mice were protected from developing systemic inflammation, insulin resistance, and fatty livers, all problems that were profound in the control mice.

“We found in experimental mice that a single enzyme, DGAT1, in macrophages is involved in many of the problems associated with obesity,” said Koliwad.

“This is exciting because humans have this enzyme as well, providing the potential for a therapeutic target to examine,” he added.