Hint hint on Alzheimer's

For not turning up in KL, my friend has forwarded to me two articles on Alzheimer's

Blood sugar loss may trigger Alzheimer's
Wed Dec 24, 2008 6:43pm GMT
LONDON (Reuters) - A slow, chronic reduction of blood sugar to the brain could trigger some forms of Alzheimer's disease, U.S. researchers said on Wednesday.

The study of human and mice brains suggests a reduction of blood flow deprives energy to the brain, setting off a process that ultimately produces the sticky clumps of protein researchers believe is a cause of the disease, they said.

The finding could lead to strategies such as exercise, reducing cholesterol and managing blood pressure to keep Alzheimer's at bay, Robert Vassar and colleagues at Northwestern University's Feinberg School of Medicine in Chicago reported.

"This finding is significant because it suggests that improving blood flow to the brain might be an effective therapeutic approach to prevent or treat Alzheimer's," Vassar, who led the study, said in a statement.
"If people start early enough, maybe they can dodge the bullet."

Alzheimer's disease is incurable and is the most common form of dementia among older people. It affects the regions of the brain involving thought, memory and language.

While the most advanced drugs have focussed on removing clumps of beta amyloid protein that forms plaques in the brain, researchers also are looking at therapies to address the toxic tangles caused by an abnormal build-up of the protein tau.

Vassar and colleagues analyzed human and mice brains to discover that a protein called elF2alpha is altered when the brain does not get enough energy. This boosts production of an enzyme that in turn flips a switch to produce the sticky protein clumps.

The finding published in the journal Neuron could lead to drugs designed to block the elF2alpha production that begins the formation of the protein clumps, also known as amyloid plaques, Vassar added.

"What we are talking about is a slow, insidious process over many years," he said. "It's so mild (people) don't even notice it, but it has an effect over time because it's producing a chronic reduction in the blood flow."
(Reporting by Michael Kahn; Editing by Michael Roddy)
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Sleep gives brain disease warning
Restless sleep may be a bad sign in some people
Physically "acting out" dreams when asleep could be an early warning sign of dementia or Parkinson's disease.

Canadian researchers studied 93 people with "REM sleep behaviour disorder", which can involve punching or kicking out while dreaming.

The Neurology study found more than a quarter were diagnosed with a degenerative brain condition over the next five years.

UK experts said the research could help doctors predict the condition.

Normally, during "Rapid Eye Movement", or "REM" sleep, our muscles relax and do not move, but people with certain sleep disorders are able to lash out, or cry out.

It is a known symptom of some kinds of brain disease, including Parkinson's disease, and a rare form of dementia called Lewy body dementia.

The exact reason for the link is unclear, although some have suggested that subtle damage to a part of the brain which regulates sleep may be responsible.

However, in some cases, the problem happens long before the onset of the main symptoms of these diseases, and doctors at Montreal General Hospital wanted to see whether apparently otherwise healthy people with the problem were at higher risk.

Their study volunteers were all elderly - on average 65 years old - which already put them at higher risk of developing dementia or Parkinson's compared with a younger person.

However, each was followed on average for five years, and in that period, 26 of the 93 developed a degenerative brain disease.

In total, 14 were diagnosed with Parkinson's disease, seven with Lewy body dementia, four with Alzheimer's Disease, and another diagnosed with a disorder called multiple system atrophy, which involves both Parkinson's and dementia symptoms.

High chance

Their predictions suggested that patients of this age with the same sleep disorder would have a greater than 50/50 chance of falling prey to a similar condition over the following 12 years.

The researchers said that knowing more about the risks faced by people with the sleep disorder could not only help doctors to advise their patients, but also to work in the years to come to come up with ways to protect them.
Dr Susanne Sorensen, head of research at the Alzheimer's Society, said that the findings were particularly interesting in relation to Lewy body dementia, which accounts for only 4% of dementia cases.
The researchers had said that even the four Alzheimer's cases might turn out to be Lewy body dementia as the disease progressed.
Dr Sorensen said: "People with Lewy body dementia often have vivid nightmares, restless sleep and hallucinations - this study suggests that people with the disease may experience sleep disorders years before their other symptoms develop.
"This important finding could boost our understanding of how Lewy body dementia develops and help us detect it early. With further research we may be able to stop this devastating disease in its tracks."