[ad_1]
Scientists believe that patients with Alzheimer's disease could improve their memory by unblocking the blood vessels in the brain.
Alzheimer's disease is known to reduce blood flow to the brain and research has shown that it could be caused by white blood cells sticking to the inside of blood vessels.
And, in a mouse study, memory and brain performance were quickly improved when scientists removed these blockages.
According to experts, the same mechanism could apply to the millions of people suffering from the disease in the world.
The memory of patients with Alzheimer's disease could be improved by unblocking the blood vessels in the brain, scientists hope thanks to a model study done on mice
The researchers came across the discovery by chance, when Nozomi Nishimura, an badociate professor at the Cornell University Meinig School, was attempting to put clots in the blood vessels of the Alzheimer's mouse brain to see their effect .
"It turns out that … the blockages we were trying to create were already there," she said.
"This has somehow reversed the search – it's a phenomenon that was already happening."
Professor Nishimura worked with Professor Chris Schaffer over the next decade to discover that only about two percent of brain capillaries had these blockages or "stalls".
But the cumulative effect of this small number of stalls was an overall decrease in cerebral blood flow of about 20%, due to the slowing of the vessels downstream by the blocked capillaries.
Recent studies suggest that cerebral blood flow deficits are one of the first detectable symptoms of dementia, suggesting that this could also be helpful for diagnosis.
To test their theory that it was white blood cells stuck to the inside of the capillaries, the smallest blood vessels in the brain, the team "unblocked" the vessels.
They gave mice with Alzheimer's disease an antibody that interfered with white blood cell adhesion to the capillary walls.
WHAT IS ALZHEIMER'S DISEASE?
AIzheimer's disease is a progressive degenerative brain disorder in which an accumulation of abnormal proteins causes the death of nerve cells.
This disturbs transmitters that transmit messages and causes contraction of the brain.
More than 5 million people suffer from the disease in the United States, where it is the 6th leading cause of death.
WHAT HAPPENS?
When brain cells die, the functions they provide are lost.
This includes memory, orientation and the ability to think and reason.
The progression of the disease is slow and gradual.
On average, patients live five to seven years after diagnosis, but some may live for ten to 15 years.
FIRST SYMPTOMS:
- Short-term memory loss
- disorientation
- Behavioral changes
- Mood swings
- Difficulty managing money or phoning
SUBSEQUENT SYMPTOMS:
- Loss of serious memory, forgetfulness of close family members, objects or familiar places
- Becoming anxious and frustrated with an inability to understand the world, leading to aggressive behavior
- Finally lose the ability to walk
- May have problems eating
- The majority will eventually need 24-hour care
Source: Alzheimer's Association
This increased blood flow to the brain, indicated the results published in Nature Neuroscience.
This improved memory in a few hours, even in older mice with more advanced stages of Alzheimer's disease.
Although it worked in the mouse, the team still needs to determine if it could work with humans.
An antibody can not be used in humans and interference with white blood cell adhesion would affect an individual's immune system.
"We have identified the cellular mechanism responsible for reducing cerebral blood flow in models of Alzheimer's disease, namely neutrophils. [white blood cells] sticky in the capillaries, "said Professor Schaffer.
& # 39; We have shown that when we block the cellular mechanism [that causes the stalls], we obtain an improvement of the blood circulation, and badociated with this improvement of the blood flow, an immediate restoration of the cognitive performances of the tasks of spatial memory and work.
"Now that we know the cellular mechanism, the identification of the drug or the therapeutic approach used to treat it are much narrower."
About 20 drugs, many of which have already been approved by the FDA for human use, have been identified as having therapeutic potential in the treatment of dementia.
Some of them, however, have been designed to be taken in high doses for short periods to treat sepsis, or just after a heart attack or stroke.
Although they are not ideal for a long-term take, Prof. Schaffer said that they are still testing these drugs in the Alzheimer's mice.
Professor Schaffer said it was "extremely optimistic" that if the same mechanism of capillary blockage is at play in humans as in mice, this line of research "could completely change the situation for people with the disease." d & # 39; Alzheimer's. "
It is thought that Alzheimer's disease is caused by an abnormal accumulation of proteins in and around brain cells.
Research has shown that many people with Alzheimer's also have damage to the blood vessels in their brains, suggesting that this damage may affect the progression of the disease at an early stage.
Research has shown that a reduction in blood flow prevents brain cells from receiving the oxygen and nutrients they need, which could even further impair memory.
Alzheimer's disease is the most common type of dementia. It affects 62% of the 850,000 people diagnosed in the UK.
Source link
