Biology

Does Alzheimer's originate outside the brain?

Does Alzheimer's originate out...
New research suggests Alzheimer's disease could originate in parts of a body other than the brain
New research suggests Alzheimer's disease could originate in parts of a body other than the brain
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Two mice a surgically attached so they share a bloodstream allowing scientists to explore where blood-traveling proteins can infiltrate the brain
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Two mice a surgically attached so they share a bloodstream allowing scientists to explore where blood-traveling proteins can infiltrate the brain
New research suggests Alzheimer's disease could originate in parts of a body other than the brain
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New research suggests Alzheimer's disease could originate in parts of a body other than the brain

Scientists have long thought that Alzheimer's disease originates in the brain, but new research suggests that a key protein that triggers the disease could be carried to the brain from elsewhere in the body. The research offers pathways to new drug therapies that could potentially stop or slow the disease without working directly on the brain.

One of the fundamental symptomatic causes of Alzheimer's disease is an accumulation, or "clumping", of amyloid beta proteins in the brain. These accumulations are called amyloid plaques and they smother brain cells, resulting in inhibited nerve function and impaired memory.

Several promising recent studies have shown the potential for an early-warning diagnostic blood test to be developed that identifies the build-up of these amyloid beta proteins in the bloodstream. But until now it was generally considered that the plaque-generating proteins responsible for Alzheimer's were produced inside the brain.

A new study from Chinese and Canadian scientists shows that amyloid beta proteins produced in other parts of the body can in fact cross into the brain and contribute to Alzheimer's-like symptoms.

The process was identified using a technique called parabiosis, where two separate organisms are surgically attached to share the same bloodstream. The researchers joined a normal mouse with a partner that was genetically modified to produce high levels of the amyloid beta protein.

Two mice a surgically attached so they share a bloodstream allowing scientists to explore where blood-traveling proteins can infiltrate the brain
Two mice a surgically attached so they share a bloodstream allowing scientists to explore where blood-traveling proteins can infiltrate the brain

After 12 months of connected blood circulation the normal mice connected had effectively "contracted" Alzheimer's disease from their genetically-modified partner. The proteins had traveled into the brains of the normal mice and developed into plaques causing a variety of Alzheimer's-like symptoms. Effects were noticed in the healthy mice after as little as four months.

The researchers suggest that this is the first proof that amyloid beta produced outside of the brain can in fact contribute to the disease. Outside of the brain, amyloid beta is also produced in muscles, blood platelets and blood vessels. The hypothesis is that as we get older more amyloid beta crosses into the brain, amplifying the degenerative aspects of Alzheimer's.

"The blood-brain barrier weakens as we age," says Weihong Song from the University of British Columbia. "That might allow more amyloid beta to infiltrate the brain, supplementing what is produced by the brain itself and accelerating the deterioration."

The study suggest that drug therapies could be developed to target amyloid beta in the body and push it towards the kidneys or liver to clear it from a system before it can accumulate in the brain, which is a difficult target for drug treatments.

The research was published in the journal Molecular Psychiatry.

Source: University of British Columbia

7 comments
rederje
Alzheimer's disease is proven to be associated to junk food with too much sugar and too many chemicals poisons, to obesity and to no exercising, (compare number of Alzheimer's diseases in country with no junk food, like old Japan, to USA ). Never eat junk food and exercicing are the best drug.
BrianK56
Was just reading an article about Gut bacteria and how it impacts the rest of the body. Source R&D news letter
Don Duncan
rederje: It's not as simple as junk or no junk food. Food varies in nutrition. Eating nutrition dense food is extremely difficult when the USDA & FDA severely impair commerce. Do not be distracted by govt. stated goals or general policy intention. Those are irrelevant. So is the integrity of the bureaucrats. The flaw that destroys is the assumption a govt. bureaucracy using violence (law) can force a better life on all. That belief promotes social/economic suicide. And it is the mass superstition, forced on all and defended beyond all evidence to the contrary. It kills individual innovation and local community cooperation. The trend is towards greater centralized control the world over, with devastating economic results. But the myth persists because it is not identified as the cause. The blame is put on economic freedom (which is the cure) and more govt. intervention is called for. In the name of law & order, we are being protected to death. Why? Fear of self-reliance, self-governance, and our neighbors. Voluntary social interactions (choice) is the political paradigm we need to replace the old compulsion by elites. That works. That is freedom.
BlueOak
While interesting, the above healthy mouse sharing sick mouse blood circulation study as described, does *not* show or even necessarily hint that Alzheimers is originally and naturally caused by proteins originating outside the brain. It only shows that if you introduce the proteins into the blood steam, the subject might contract Alzheimers. Real world (natural) Alzheimers might still originate from proteins within the brain. The real and scary lesson here is for the Red Cross and their Blood Donation program. It would appear they need to test for yet another bug in the donor blood!
warren52nz
Sucks to be a lab mouse it seems...
Wolf0579
Don Duncan, go back to logic class. If not for several Federal agencies it's quite probable that we in the US, wouldn't have any clean air to breath or clean water to drink. I remember the LAST river in Michigan you could drink from (the Boardman.) All the others were too polluted to drink. That was 30 years ago. It wasn't the government that polluted those rivers. It was Businesses. It wasn't the government that killed a billion humans with cigarettes... is was BUSINESS. Corporations have no conscience. They exist solely to make money, no matter the impact on people or the environment. That's why we NEED a government that is POWERFUL ENOUGH TO CHECK THE CORPORATIONS.
Robert Schreib
When human beings sexually climax, their saliva glands emit some kind of an enzyme that disintegrates chewing gum. Chewing gum is type of latex rubber, which if swallowed, is not digested, but has to pass through the person's entire gastrointestinal tract intact. Stomach acid cannot dissolve it, but somehow, this 'climax enzyme does. So, what if this enzyme has another effect, besides possibly disintegrating tooth plagues, of clearing out the Amyloid Beta plaques in the brain that causes Alzheimer's disease? Or clear their arteries of fatty plaques? They say that people who have lots of sex live longer, and what if this thing is one of the reasons why that is so? If so, it might be feasible to obtain a sample of this 'climax enzyme', analyze it, and then synthesize a very powerful molecular analog of it, a new drug that can be used to cure Alzheimer's disease patients?