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Show 1132: Are Infections to Blame for Alzheimer Disease?

Pharmaceutical scientists have been striving to get amyloid plaques out of the brain, but new research suggests that amyloid may be acting to protect the brain from microbes. What are the implications
Assistant professor of neurology, Harvard Medical School
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Are Infections to Blame for Alzheimer Disease?

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With nearly six million Americans living with Alzheimer disease, this condition is a serious public health problem. It robs people of their memories, their ability to function independently and even their very identities.

When Alois Alzheimer published the first report on the brain disease that was later named for him, he described distinctive plaques and neurofibrillary tangles in the brain. That was in 1906. Ever since then, scientists have been trying to figure out what causes those plaques and tangles and how we can prevent them.

Researchers have known for decades that the plaques that characterize Alzheimer disease contain a lot of beta-amyloid peptide. They call it A-beta. Drug companies have been struggling to find pharmaceuticals that can clear this bad actor out of the brain. Unfortunately, the agents they have tested so far have been disappointing at best.

What Is A-Beta Doing in the Brain?

Neuroscientists have assumed that A-beta is toxic to neurons, and that it has no legitimate business in the brain. But that assumption may be mistaken.

New research demonstrates that A-beta is part of the brain’s immune defenses. It seems that it has played an important role in protecting the brain from infection throughout human evolution.

The Microbiome of the Brain:

Our guest, Robert Moir, and his colleagues have found that the brain has a complex, previously unsuspected, microbiome. The A-beta compound that makes up amyloid plaques is a powerful antibiotic–100 times more potent than penicillin.

He is now studying ways to find anti-inflammatory compounds that target innate immunity of the sort found in the brain. He suggests that all of us can help our brains by eating a heart-healthy diet (it’s good for the brain, too), staying fit with regular exercise and drinking alcohol in moderation if at all.

If A-beta is actually acting to protect the brain, it could be a mistake to try to get rid of it. Instead, perhaps we should figure out how to help it. Our second guest, Dr. Dale Bredesen, also has a number of suggestions on how we can do that and reduce our risk of Alzheimer disease. He suggests measuring ketones and aiming for a sweet spot between 1.5 and 4 millimoles of beta-hydroxy-butyrate.

NPR did an in-depth report on the possibility that Alzheimer disease is caused in part by infection and the immune system’s response on Sept. 9, 2018.

You may also be interested in this in-depth report of Dr. Moir’s research process in STAT.

This Week’s Guests:

Robert D. Moir, PhD, is Assistant Professor in Neurology at Harvard Medical School. He is also Assistant Professor in Neurology at MGH Neurology Research. His research focuses on the biochemical and cellular mechanisms involved in neurodegeneration in Alzheimer disease and aging. His most recent publication is on herpes virus and beta-amyloid in Neuron, July 11, 2018.  The photo is of Dr. Moir.

Dale Bredesen, MD, is an expert in the mechanisms of neurodegeneration and has served on the faculty at the University of California, San Francisco, and UCLA. He directed the program on Aging at the Burnham Institute prior to joining the Buck Institute for Research on Aging as its founding president and CEO. We spoke with him via Skype.

His book is The End of Alzheimer’s: The First Program to Prevent and Reverse Cognitive Decline.

If you want to read some of Dr. Bredesen’s scientific publications, we suggest “Ayurvedic Profiling of Alzheimer’s Disease,” with DV Rao (Alternative Therapies in Health and Medicine, May 2017) or “Reversal of Cognitive Decline in Alzheimer’s Disease,” with numerous colleagues (Aging, June 2016).

Listen to the Podcast:

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About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies. .
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comments (21 total)
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There are concepts that both speakers should investigate that will help integrate their excellent models of disease with the underlying cause of disease. They can glean these concepts by doing the following literature searches:

1) innate immunity AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

2) antimicrobial peptides AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

3) Alzheimer’s Disease AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

4) Neurodegeneration AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

5) medical condition of YOUR choice AND (“oxidative stress” or “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

(HIV OR treponema OR herpes OR influenza OR CMV OR “Lyme disease” OR parasite OR bacteria OR plasmodium OR fungus OR virus) AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

Toxin AND (“oxidative stress” OR “endothelial dysfunction” OR NF-kB OR Nrf2 OR “redox balance”)

Exercise AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Diet AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Neuropsychiatric AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Microbiome AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Neurotrophic AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Inflammation AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

Pathogen AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

(sepsis OR microorganism OR bacteremia OR viremia) AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance” OR thiamine)

Epigenetics AND (“oxidative stress” OR NF-kB OR Nrf2 OR “endothelial dysfunction” OR “redox balance”)

My main point is that both speakers are missing the inclusion of some very fundamental concepts in their model building process of what Alzheimer’s disease pathophysiology is AND WHY it occurs AND HOW we can treat it and, more importantly, prevent it.

Excellent show, Joe and Terry! I’ve learned so much from Dr. Bredesen and his book, thanks to your show that introduced him to me and so many others back in May 2015!

By the way, I noticed that you’re now calling it “Alzheimer disease” (instead of Alzheimer’s disease)–I started to wonder if I had been calling it by the wrong name! I googled both versions and can only find the possessive form, including the Alzheimer’s Association, the NIH, and Dr. Bredesen’s book title. What’s behind the name change?

Hi Howard,
Part of the motivation behind the change is practical: our software doesn’t like apostrophes in titles. The other part is a matter of style. Here’s a short discussion: https://dragonflyeditorial.com/blog/dropping-the-possessive-in-eponymous-medical-terms/

Research is now questioning if the HSV-1 virus is the cause of Alzheimer’s and possibly brain cancer.

There are whole families affected by AD and who carry a gene that seems to predispose them to the disease. I don’t see how infection could be the cause in these cases. I also think that those living with a person suffering from AD will grasp at anything in the way of help and that they are therefore easy prey for peddlers of fraudulent treatments or cures.

I like your thoughts. I think we will soon come to see that Alzheimers is a lot of diseases.

Pathogens are a very likely culprit. The CDC is being sued right now for not updating guidelines on which serology tests to use for Lyme disease. Lyme is not the only suspect. EBV, mycotoxins, and others should be investigated.

At the moment, a combination of anti-pathogenic medicines, supplements, and a combination of the right oils (for examples with mct fatty acid chains), ketosis, and adequate nutrients including Bs and magnesium are probably the beginning of retarding cognitive destruction.

EXCELLENT program! All reviewers, please visit https://www.drbredesen.com/mpicognition before you comment. I am a PhD biostatistician with over 30 years experience, over 75 research articles, and have worked on multiple NIH-funded research projects.
Dr. Bredesen’s team discovered dependence receptors in 1993 (see the Wikipedia article). Their discovery was hugely significant! It has inspired hundreds of papers on cancer metastasis and autoimmune disease (and well as dementia and other conditions).
(Skeptics, see http://www.drbredesen.com/bredesenprotocol)
My wife has been on Dr. Bredesen’s protocol ever since she first experienced mild cognitive impairment. We use several objective ways to measure her cognition. Dr. Bredesen’s protocol is working. Enough said.

There was mention on this program of a place that pairs patients with medical people for research. It said to go to Doctor Rosen….. I can’t find it. Could you please supply a link.


Thank you so much for this FIVE STAR informative and wonderful show on the role of beta amyloid in the brain. These are such crucial insights which, in my view, mirror recent revelations that it’s not always effective to focus on reducing cholesterol, because cholesterol turns out to be the “spackle truck” that shows up to patch distressed blood veins. Perhaps beta amyloid is the spackle truck in the brain. In both cases, reducing the excess “plaster” frees up blood flow temporarily. But in both cases, those efforts are focused on the wrong villain.

These insights are so important for the future direction of research! Separately, I know that you prefer that we put our reviews on iTunes, and many of us aren’t listening on iTunes — we are listening Live on public radio. It’s not easy to track down your show on iTunes, and iTunes does not make it easy to review when they can tell we did not listen to it there, since they have no way to know we listened at all. So I am hoping you are still glad that those of us listening on public radio are reviewing on your website! Warm regards from Front Royal, Virginia, julie

What do I think? I think that we don’t know nearly enough about the brain and meddling with it, even in the name of knowledge, can be a potential disaster.

Please clarify as to when the broadcast and the podcast will be available.

The broadcast was initially available at 7 am EDT on August 11, 2018. The podcast will be posted on August 13, 2018.

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