Is There a Brain Microbiome? 21
An anonymous reader quotes an opinion piece from The Guardian, written by Prof Mark Pallen and Dr Aimee Parker (Quadram Institute, Norwich), Prof Nick Loman (University of Birmingham), Prof Alan Walker (University of Aberdeen): Contrary to what is implied in [this article], the weight of expert opinion in medical microbiology rejects the existence of a "brain microbiome" in the sense of a resident microbial community in healthy human brains. While pathogenic microbes -- such as Borrelia burgdorferi, which causes Lyme disease, or fungal pathogens like Cryptococcus neoformans -- can invade the brain and cause neurological symptoms, these are examples of infections, not evidence of a native microbial community.
Similarly, cognitive benefits of vaccines can be explained by their role in preventing infections or modulating immune responses and inflammation, rather than any impact on a "brain microbiome." Furthermore, the studies cited in the article have not undergone independent validation, nor do they provide any kind of consistent picture. This mirrors controversies around other supposed microbiomes -- such as that of the placenta -- which have failed to withstand independent scrutiny. Over a decade of research indicates that contamination, typically from laboratory reagents, is the most plausible explanation for such findings, particularly when even supposedly ultrapure water has been shown to harbor DNA signatures and culturable microbes.
If diverse microbes are truly abundant in the brain, why have they not been repeatedly and consistently cultured in over a century and a half of medical microbiology? Why have they not been observed in numerous microscopy studies of human brain tissue? Efforts to explore overlooked roles of microbes in neurological conditions are welcome, but they must be grounded in robust and reproducible science -- not speculative discussion of a "brain microbiome." In the article mentioned above, author Amy Fleming discusses the emerging research connecting infections such as Borrelia, Cryptococcus, and herpes viruses to reversible dementia, challenging the long-held belief that the brain is sterile.
She highlights the Alzheimer's Pathobiome Initiative, which investigates how brain infections may contribute to diseases like Alzheimer's, with the goal of developing new diagnostic tools and treatments. Vaccines like BCG and zoster have shown protective effects, while good hygiene, oral health, and a healthy lifestyle can help reduce risks.
Similarly, cognitive benefits of vaccines can be explained by their role in preventing infections or modulating immune responses and inflammation, rather than any impact on a "brain microbiome." Furthermore, the studies cited in the article have not undergone independent validation, nor do they provide any kind of consistent picture. This mirrors controversies around other supposed microbiomes -- such as that of the placenta -- which have failed to withstand independent scrutiny. Over a decade of research indicates that contamination, typically from laboratory reagents, is the most plausible explanation for such findings, particularly when even supposedly ultrapure water has been shown to harbor DNA signatures and culturable microbes.
If diverse microbes are truly abundant in the brain, why have they not been repeatedly and consistently cultured in over a century and a half of medical microbiology? Why have they not been observed in numerous microscopy studies of human brain tissue? Efforts to explore overlooked roles of microbes in neurological conditions are welcome, but they must be grounded in robust and reproducible science -- not speculative discussion of a "brain microbiome." In the article mentioned above, author Amy Fleming discusses the emerging research connecting infections such as Borrelia, Cryptococcus, and herpes viruses to reversible dementia, challenging the long-held belief that the brain is sterile.
She highlights the Alzheimer's Pathobiome Initiative, which investigates how brain infections may contribute to diseases like Alzheimer's, with the goal of developing new diagnostic tools and treatments. Vaccines like BCG and zoster have shown protective effects, while good hygiene, oral health, and a healthy lifestyle can help reduce risks.
Not the Same Thing (Score:5, Funny)
RFK, Jr. calls it worm food. :-)
That's an example of a microbrain biome which is not the same thing as a brain microbiome.
Re: (Score:2)
Hey, give him a break. He just has a little buddy that he only needs to take out for a walk and feed once a week, his personal comfort pet.
Re: (Score:1)
Brain Hurts (Score:2)
My brain hurts just reading this. Can I get something for that doc?
--
America's health care system is neither healthy, caring, nor a system. - Walter Cronkite
No (Score:1)
Jury still out (Score:2)
From all I have read, it is highly unlikely that anything equivalent to the microbiome in our digestive tracts exists in the brain. However, the presence of a limited group of protective organisms seems plausible. As hinted by TFA, circumstantial evidence suggests conditions like Alzheimer's are affected by gut bacteria. The most likely reason for such an effect seems those organisms crossing the blood brain barrier and acting directly within the brain. Really, though, we simply do not know yet.
Re: (Score:1)
So poor experiments result in no data? (Score:2)
So the researchers do not know how to do experiments properly and hence they mistrust their own studies and then say "there is no evidence". Gather some f'''ing evidence then! The article names several microbes that can reach the brain, COVID-19 i
Re: (Score:3)
Penicilin has been discovered because of contaminated petri dishes. So no, poorly conducted experiments still yield data, sometimes valuable data that leads to scientific breakthroughs.
Covid-19 is a virus, not a bacterium. Viruses do not microbiomes make. Or any biomes.
It is a bit rich to demand that scientists should go and gather evidence for something that doesn't exist.
Re:bacteria never "invade the brain" or any tissue (Score:4, Informative)
Some bacteria don't wait for tissue to be dead. That's how you get bacterial infections. And that is why antibiotics can cure those infections.
Life forms are not assigned roles, they find niches in which they can survive. That's why you need an intact immune system to not be eaten alive by microbes.
If there was (Score:2)
It could explain all the stupidity in the world.
Not a useful question atm (Score:3)
There seem to be three standard rules.
1. Anything that is not demonstrably impossible is technically possible.
2. Within the set of what is technically possible, we need only look at the subset of simplest explanations.
3. Within the subset of simplest explanations, we need only consider those for which the level of evidence equals or exceeds the improbability of correctness.
A brain microbiome is technically possible, but it is not in the subset of simplest explanations, nor is the level of evidence sufficient. As such, It fails both the second and third tests.
To me, this does not mean we reject it outright, it means we simply don't consider it at all for right now. We neither accept nor reject, we simply put it to one side and see what scientists find in future. It's not a model we can usefully explore or make predictions with that would permit falsification.
Scientists are finding all kinds of new communications channels and behaviours within the brain. Clearly, our knowledge is nowhere near adequate to determine what is required. Let's get that sorted first, and then decide if there is anything left that needs a microbiome explanation.
Re: (Score:2)
There seem to be three standard rules.
1. Anything that is not demonstrably impossible is technically possible.
2. Within the set of what is technically possible, we need only look at the subset of simplest explanations.
3. Within the subset of simplest explanations, we need only consider those for which the level of evidence equals or exceeds the improbability of correctness.
A brain microbiome is technically possible, but it is not in the subset of simplest explanations, nor is the level of evidence sufficient. As such, It fails both the second and third tests.
To me, this does not mean we reject it outright, it means we simply don't consider it at all for right now. We neither accept nor reject, we simply put it to one side and see what scientists find in future. It's not a model we can usefully explore or make predictions with that would permit falsification.
Scientists are finding all kinds of new communications channels and behaviours within the brain. Clearly, our knowledge is nowhere near adequate to determine what is required. Let's get that sorted first, and then decide if there is anything left that needs a microbiome explanation.
Your set-theoretic framework for evaluating the brain microbiome hypothesis is logical and well-constructed, but I believe it might lead to overly restrictive conclusions in this case.
Rule 1: Anything that is not demonstrably impossible is technically possible.
Agreed, the brain microbiome is technically possible. Emerging evidence from studies--such as the detection of microbial DNA in brain tissue--suggests it cannot be dismissed outright. While the challenges of culturing micr
Betteridge's law (Score:2)
Yes (Score:2)
Toxoplasma gondii
Re: (Score:2)
Correct. For those who don't know what it is, it's carried by cats and a large fraction of cat owners have been colonized by it. The theory behind it is that it makes cats' prey more docile and oblivious to the danger from cats.
Still early days (Score:2)
I'm not a brain scientist, but considering that up until about 10 years ago, we didn't know that there were meningeal lymphatic vessels (a connection from the lymphatic system to the brain) and that the blood brain barrier isn't as much of a barrier as we thought, I'd say we have a lot more to learn before we start outright rejecting hypotheses about what is or isn't in our brains.