Alzheimer’s May Not Start in the Brain

By Lacy Schley | November 1, 2017 11:24 am

(Credit: Shutterstock)

For years, experts thought Alzheimer’s, a progressive neurodegenerative disease, originated in the brain. After all, it’s the organ that takes the beating: Proteins build up in the brain, forming plaques or tangles that can damage cell function.

And depending on which hypothesis you’re reading up on, the critical damage that kick-starts symptoms comes from either beta-amyloid proteins, the traditional suspects, or tau proteins, a relatively new but increasingly popular pick for the potential culprits.

Recently, though, studies have come out that suggest other bodily systems, like the gut, could play a not-insignificant role in the disease’s onset. And now, a new paper published in Molecular Psychiatry, supports that nascent line of thinking by claiming that our blood could also be a player.

An international team of researchers worked with two sets of mice: One set was genetically engineered to produce high levels of a human-specific beta-amyloid and the second was normal and healthy. The group then surgically joined the healthy mice with the diseased mice, a technique called parabiosis, so that the two would share blood supplies anywhere from two months to a year.

Mice who swapped blood for at least four months developed no shortage of human-specific beta-amyloid plaques in their brains. And, in some healthy mice, brain cells involved in learning and memory were already having trouble signaling to each other at the four-month mark.

One of the paper’s authors, Weihong Song, a psychiatry professor at University of British Columbia, explains these symptoms started cropping up in the healthy mice because beta-amyloid was traveling from their diseased partner’s blood and making its way to their once-normal brains. While experts knew other parts of the body produce beta-amyloid, all this time, they largely thought the buildups we see in Alzheimer’s patients originated from the brain cells themselves. These results shine a light on the fact that the protein can make its way to the brain from other areas and have an impact on the disease’s development and progression.

This realization should help researchers keep in mind how the body as a whole impacts Alzheimer’s disease. “There is so much narrowing of focus on the brain,” Song says, “but we also have to think about other systems.”

  • CarolAST

    Unless there’s evidence that Alzheimers patients have high levels of beta-amyloid in their blood, it means nothing.

    • William Holz

      Would that have to be a constant state though? Could somebody have high levels of beta-amyloid in their blood for a time, damaging the brain, and then at a later point in time NOT have high levels but still have the damaged brain?

      The answer is yes, correct?

      • Ken Chapel

        with such wide use of antibiotics it would be hard to show a causal relationship to dementia ….but, intuitively it makes since…I always take a potent probiotic for 30 days following any antibiotic prescription….

  • chad hatten Albuquerque

    Good iinformation

  • nik

    The Chinese consider that keeping the whole body’s systems in balance is the key to good health. Seems logical really.

    • Bharati_shahida

      FWIW, most of Chinese medicine came from India’s (mostly Hindu) Ayurveda. e.g acupressure, many herbs, 5 colours in every meal, etc. The Chinese Ambassador to the UN said, For 20 centuries India conquered China without sending a single soldier. Ayurveda works on the whole body and has had success treating AIDS, cancer etc. Many desperate patients come when their bodies are already exhausted with chemo, assorted powerful drugs, huge depression, so it is hard to improve them. Of course today we are all interested in benefiting from whoever can teach us.

      • nik

        Yes, and Europe also had a herbal base for medicine, which was comprehensive, but it was mostly lost, when ”Doctors” emerged, and accused the herbalists of witchcraft, and had them burnt to death.
        Skeletons exhumed by archaeologists have shown that ancient Brits, survived horrendous injuries, that even today people would be lucky to survive. Some ”doctors” [ignorant ones] still consider herbal remedies as ‘witchcraft’ when in fact more than 70% of ‘modern’ remedies were originally derived from plants, Aspirin, and the contraceptive pill, come to mind immediately, and of course modern anaesthetics were also derived from plants originally.
        My motto is, ”You are what you eat” so do make your diet comprehensive, and ensure that everything is in moderation.
        I wonder how many modern ‘diseases’ are actually caused by dietary deficiencies, rather than infections.
        Hunter-gatherers had a vastly more varied diet than modern ‘supermarket man.’ Supermarkets stock what gives them the most profit, and the same goes for farmers, so the range of modern foods is severely limited, and so, consequently is the range of nutrients that modern man consumes.
        In addition, with artificial fertilisers, the farmers now grow the same crops on the same ground, year after year, so the nutrients that the plants should have are often depleted, and therefore deficient. Certainly a lot of ‘mental’ and other problems can be diagnosed as due to chemical deficiencies or excesses caused by modern foods.
        Some of the crap that is put into food, as ”bulking agent” can be positively dangerous, even though its supposed to be indigestible and therefore ‘safe.’
        I know, from bitter experience!
        I think that doctors would do well to look at the diets of people with Alzheimer’s and see if there was any common factors, that could be investigated.

        • Doug

          I agree with you. Lookup Linus Pauling (2 time Nobel Prize Winning). He attributed the majority of human ailments to nutirent deficiencies in our diets.

          • nik

            I’ve cured or reduced several of my health problems with dietary supplements, and/or simple herbal remedies.
            Ancient man had thousands of years to research herbs and their diets. Modern ‘pharmacy’ has had maybe 100 years, and they are profit motivated, not health motivated. In fact some of their products are designed to promote long term health problems that they can then sell ”cures” for, for the rest of the victims life.

          • Doug

            Feed the body the nutrition it needs and it will do amazing things to be healthy. Howver, wthout including good quality supplements as part of our diet, getting all our daily nutrients from store bought food is almost impossible. Even eating healthy doesn’t guaranty getting all the nutrients eeded.

          • nik

            Its my theory, that part of the reason for the obesity epidemic in the USA and other western countries, is caused by malnutrition, but not lack of food, of which there is an excess.
            Specific food plants grown in the same ground year after year, will deplete that ground of specific nutrients, and trace elements. Each plant selects and stores its own range of nutrients. and trace elements. As these plants eventually become deficient, so do the humans that eat them.
            Their bodies demand food for the nutrition they need, but when the food is deficient, then they will keep demanding food, leading to and excess of calories, that are stored, while their bodies are still deficient of the required nutrients.
            Some years ago, I was suffering from acute serotonin deficiency, brought about by a nasty pharmaceutical drug, prescribed by a stupid doctor, that I didnt need, and that I took on trust. (I will never do that again.)
            During that problem I developed a craving for dates, and almonds, and was eating them throughout the day. I later found that they were effective in relieving serotonin deficiency, so my body had demanded the specific foods to alleviate the problem.
            Those people in the western world where obesity is rife, will eat the foods their bodies demand, but as almost all of the foods are ‘factory’ farmed, they are all deficient.
            Hence the obesity.

          • Doug

            This isn’t just your theory. It is a known fact that todays fruits and vegetables have less nutrition then they did 50 years ago due to nutrient depleted soils.
            It has been coined that North Americans are the most over-fed, undernourished people in the world.
            Larger portions have to be consumed to get our required nutrients and even then many of the vitimins & minerals are no longer available. We eat and are not satisfied so we eat more. Vitimins & minerals are added to foods but not in a form that our body can absorb. Over 90% of supplements are also not in a form the body can use. Add to this artificial sweeteners, fillers, preservatives, insecticide, herbicides, global warming and man-made environmental contaminants …
            The earth has millions of years to recover but
            how much more can humans take?

          • nik

            Another theory.
            Why was cannabis banned?
            So that a cheap ‘cure all’ was not available, and then people are forced to accept big Pharmacy’s very expensive alternatives, and of course to boost the bankers incomes from the rocketing prices of it, and the profits to be made by money laundering!

          • nik

            PS thanks for the Lookup,

          • Maia

            Yes. AND he was badly smeared for his work around vitamin C. I don’t think anyone has ever followed up on that controversy and re-done some of the research.

          • Doug

            There have been recent studies on vitimin C showing that Pauling may have been right.

          • Maia

            Do you have any links? Haven’t seen anything at all about that for many years!

          • nik

            Just google his name, Wikipedia is a good start.

          • Maia

            Hundreds of things come up in Google searchs, so I like to follow specific people’s links. But that’s okay.

        • Maia

          Diet is usually ignored entirely in most all disease processes. A few like heart disease and diabetes, it is paid cursury attention, mainly calories and proportions of fat, carbohydrates, etc rather than the finer details…which are the most important. What KIND of fat, complex or simple carbohydrates, and even deeper into micro-nutrients. We mostly have to do this research and experimentation ourselves.

  • Doc4u

    Reminds us of the story of the four blind individuals trrying to describe an elephant.

    Generally it is best to “move the ladder” then step back to get an accurate view.

    • Doc4u

      The distinction between mind and body is artificial. Doctors who ignore this reality do so at their patients’ peril.


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