4 ms·

My understanding was that strokes caused brain cell death, and that there was no coming back from that, but my neurologists would speak of 'bruised' brain cells

My understanding was that strokes caused brain cell death, and that there was no coming back from that, but my neurologists would speak of 'bruised' brain cells, and that after weeks or months or even years you can see recovered function. UCLA's work here is targeting this disconnection and the lost rhythm in the surviving, distant networks. However there is, as yet, NO concievable intervention that could recover function from cell death at that center of the infarct.

foota 5mo ago
One wonders if someday we might be able to resurrect the neural network from dead cells by somehow reviving the connections between neurons. I imagine that the connections stay, but become dormant when the neuron dies.
- steve_taylor 5mo ago
  Perhaps, but I think that by the time we're that far advanced, strokes will be entirely preventable.
  - OneDeuxTriSeiGo 5mo ago
    Strokes will never be preventable. You can mitigate them but a stroke isn't really a disease. It's a symptom. An ischemic stroke (i.e. stroke due to a clot) caused by vascular or cardiac issues can be mitigated. A cryptogenic stroke however is idiopathic and therefore has no understood cause. These types of strokes make up 30-40% of all strokes. Unless we figure out their cause, there's no way to really prevent them. But then there's also hemorrhagic strokes which are an entirely separate category that has causes and mitigations more or less diametrically opposed to those for ischemic strokes. And of course those are just your broad painted categories and they are generally looked at as the start of a medical emergency but strokes happen all the time as a consequence of other medical emergencies. Even if you could perfectly prevent strokes in generally healthy populations, those same people may still end up suffering from a stroke during a surgery or during/after a major accident or injury. No amount of preventative medication can prevent someone suffering a stroke caused by a brain bleed after a car accident. Likewise for someone with a crush injury, internal bleeding, or broken bones that end up throwing a clot which makes it into the brain. So any advancement in halting and reversing damage from a stroke will be a massive boon for emergency medicine until the end of time. Unless of course we somehow find a way to cure/render humans immune to blunt force trauma or lacerations.
    - adastra22 5mo ago
      Sure you can. Just not with any technology on the horizon. But there is conceivable technology (e.g. medical nanotechnology) that could prevent strokes or stop them as they are happening.
      - lobotomiser 5mo ago
        Like what?
        gettingoverit 5mo ago
        Like detecting constriction or loss of integrity of blood vessels, and doing the corresponding intervention. The saddest thing here is not that it requires some future nanotechnology, but is achievable at the present scientific level, yet too expensive to develop, and wouldn't see FDA permission in a decade or two anyway.
  - s5300 5mo ago
    [dead]
- asdff 5mo ago
  There is nothing to resurrect. They get digested by the microglia.
  - foota 5mo ago
    Ah, I didn't know that existed. TIL
  - s5300 5mo ago
    [dead]
asdff 5mo ago
There are people who are missing huge percentages of their brain from injury or other issues and lead a seemingly normal life. https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-edition-1.3679117/scientists-research-man-missing-90-of-his-brain-who-leads-a-normal-life-1.3679125 https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-...
- throwup238 5mo ago
  The original paper did not say that a huge percentage of their brain was missing [1], that was the journalist's flourish based on their own misunderstanding. Tissue can be compressed, stretched, reorganized, or displaced especially to compensate for a congenital condition - the patient's brain had a lifetime to adapt to hydrocephalus, which pushed on the other brain tissue. The gray cortical shell is clearly visible in those images and their volume on a scan is not representative of neuron count or synaptic capacity. There are far more dramatic cases of brain damage and neuroplasticity that reorganizes major functions, but there are a lot of caveats. [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(07)61127-1/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
  - CamelCaseCondo 5mo ago
    Was expecting an article about https://en.wikipedia.org/wiki/Hemispherectomy https://en.wikipedia.org/wiki/Hemispherectomy
    - chmod775 5mo ago
      It's wild to me that this can have effectively no impact on a person's cognitive ability.
jmalicki 5mo ago
This talks about connections. My understanding is that while brain cell death (outside of the hippocampus, at least) cannot regenerate, the connections and networks can. But neurons regenerating connections between each other is, afaik, been pretty mainstream for awhile. The brain can't generate new cells, but it can rewire the connections between them, is what I understand. From reading the article, it seems to only claim rewiring connections, not regenerating cells. There are a ton of upcoming drugs that help stimulating rewiring, for instance: https://www.nia.nih.gov/news/new-drug-candidate-targeting-synaptic-resilience-well-tolerated-alzheimers-patients https://www.nia.nih.gov/news/new-drug-candidate-targeting-sy... https://pmc.ncbi.nlm.nih.gov/articles/PMC8190578/ https://pmc.ncbi.nlm.nih.gov/articles/PMC8190578/ https://www.medicalnewstoday.com/articles/324410 https://www.medicalnewstoday.com/articles/324410 etc.
- adastra22 5mo ago
  There is lots of neural regeneration in the brain at the cellular level. The science on this is changing quickly. But even though there are new brain cells growing, that does not mean you can reform lost structure.
- oneshtein 5mo ago
  Lion’s mane mushroom and extracts are used by boxers to repair their brains. But it cannot be patented.
  - giantg2 5mo ago
    I'm not sure why this being disagreed to without any response. There are studies related to this out on PubMed. The effects do not seem huge, but they do seem to be significantly better than placebo. And at least those studies are in humans as opposed to the main article of this post that is only in mice.
    - jghn 5mo ago
      I imagine because it reads like one of those "Big Medicine won't let you have access to stuff that works!" conspiracy theories, and also that it won't actually foster new brain cell growth.
deepsun 5mo ago
My understanding is that brain is composed of way more neurons than required, for resiliency. So if it gets a "bruise" in some part, when even a large portion of the cells are dead -- it can still function at 100%. Like a programmer without a finger. The problem is visible only when all the cells in some part are dead. That's why crows, with their low brain mass are pretty clever (and why all arguments equating brain size and smartness are wrong). Just my layman understanding.
- sigmoid10 5mo ago
  Crows (and certain other bird species) have a peculiar forebrain (different in structure but similar in function/evolution to the neocortex in mammals) with neuron counts rivalling primates. So the nr of neurons still matters, but likely not across the entire brain.
  - metalman 5mo ago
    my understanding is that extream migrators actualy consume (use as energy) parts of there own brains durring there epic flights, and other species do something similar in the winter and regrow parts of there brains every spring.
    - sigmoid10 5mo ago
      It is true that they can shrink some organs to reduce weight and store extra fat, but the brain is not one of them. Would be pretty bad, because brain cells can't regrow like e.g. a liver can.
      - metalman 5mo ago
        https://www.sciencedaily.com/releases/2010/04/100429082854.htm https://www.sciencedaily.com/releases/2010/04/100429082854.h...
  - deepsun 5mo ago
    Yep. And my point is that too many people seem to judge intellect by brain size or mass. Something like "Neanderthals must've been smarter than Sapiens, because their brains were larger". Or "chimpanzees are smarter than gorillas because gorillas have very small brains", which is all true, except for the word "because" (gorillas are leaf-eaters, so they did not have evolutionary pressure to be smarter, no need in more complex hierarchies, and maybe less proteins for the brain).
rasmus1610 5mo ago
it is more like that the brain learns to use other regions or neurons to do the tasks of the dead brain cells. The brain cells that are dead due to ischemia are dead and will usually be collected by microglia and after some time there are defects in the brain where the ischemia was.
noleary 5mo ago
There've been some interesting new developments in cell therapies over the last few years. Bemdaneprocel from BlueRock Therapeutics is now into Phase 3 trials for Parkinson's, for example. The essential idea is to implant some dopaminergic neuron precursors to grow new cells in place of cell death. Still a long way from the kind of general stroke treatment you're describing, but regenerative neuroscience is looking pretty promising. --- [1] https://www.bluerocktx.com/bluerock-therapeutics-announces-publication-in-nature-of-18-month-data-from-phase-1-clinical-trial-for-bemdaneprocel-an-investigational-cell-therapy-for-parkinsons-disease/ https://www.bluerocktx.com/bluerock-therapeutics-announces-p...

foota 5mo ago

One wonders if someday we might be able to resurrect the neural network from dead cells by somehow reviving the connections between neurons. I imagine that the connections stay, but become dormant when the neuron dies.

steve_taylor 5mo ago
Perhaps, but I think that by the time we're that far advanced, strokes will be entirely preventable.
- OneDeuxTriSeiGo 5mo ago
  Strokes will never be preventable. You can mitigate them but a stroke isn't really a disease. It's a symptom. An ischemic stroke (i.e. stroke due to a clot) caused by vascular or cardiac issues can be mitigated. A cryptogenic stroke however is idiopathic and therefore has no understood cause. These types of strokes make up 30-40% of all strokes. Unless we figure out their cause, there's no way to really prevent them. But then there's also hemorrhagic strokes which are an entirely separate category that has causes and mitigations more or less diametrically opposed to those for ischemic strokes. And of course those are just your broad painted categories and they are generally looked at as the start of a medical emergency but strokes happen all the time as a consequence of other medical emergencies. Even if you could perfectly prevent strokes in generally healthy populations, those same people may still end up suffering from a stroke during a surgery or during/after a major accident or injury. No amount of preventative medication can prevent someone suffering a stroke caused by a brain bleed after a car accident. Likewise for someone with a crush injury, internal bleeding, or broken bones that end up throwing a clot which makes it into the brain. So any advancement in halting and reversing damage from a stroke will be a massive boon for emergency medicine until the end of time. Unless of course we somehow find a way to cure/render humans immune to blunt force trauma or lacerations.
  - adastra22 5mo ago
    Sure you can. Just not with any technology on the horizon. But there is conceivable technology (e.g. medical nanotechnology) that could prevent strokes or stop them as they are happening.
    - lobotomiser 5mo ago
      Like what?
      - gettingoverit 5mo ago
        Like detecting constriction or loss of integrity of blood vessels, and doing the corresponding intervention. The saddest thing here is not that it requires some future nanotechnology, but is achievable at the present scientific level, yet too expensive to develop, and wouldn't see FDA permission in a decade or two anyway.
- s5300 5mo ago
  [dead]
asdff 5mo ago
There is nothing to resurrect. They get digested by the microglia.
- foota 5mo ago
  Ah, I didn't know that existed. TIL
- s5300 5mo ago
  [dead]

asdff 5mo ago

There are people who are missing huge percentages of their brain from injury or other issues and lead a seemingly normal life. https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-edition-1.3679117/scientists-research-man-missing-90-of-his-brain-who-leads-a-normal-life-1.3679125 https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-...

throwup238 5mo ago
The original paper did not say that a huge percentage of their brain was missing [1], that was the journalist's flourish based on their own misunderstanding. Tissue can be compressed, stretched, reorganized, or displaced especially to compensate for a congenital condition - the patient's brain had a lifetime to adapt to hydrocephalus, which pushed on the other brain tissue. The gray cortical shell is clearly visible in those images and their volume on a scan is not representative of neuron count or synaptic capacity. There are far more dramatic cases of brain damage and neuroplasticity that reorganizes major functions, but there are a lot of caveats. [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(07)61127-1/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
- CamelCaseCondo 5mo ago
  Was expecting an article about https://en.wikipedia.org/wiki/Hemispherectomy https://en.wikipedia.org/wiki/Hemispherectomy
  - chmod775 5mo ago
    It's wild to me that this can have effectively no impact on a person's cognitive ability.

jmalicki 5mo ago

This talks about connections. My understanding is that while brain cell death (outside of the hippocampus, at least) cannot regenerate, the connections and networks can. But neurons regenerating connections between each other is, afaik, been pretty mainstream for awhile. The brain can't generate new cells, but it can rewire the connections between them, is what I understand. From reading the article, it seems to only claim rewiring connections, not regenerating cells. There are a ton of upcoming drugs that help stimulating rewiring, for instance: https://www.nia.nih.gov/news/new-drug-candidate-targeting-synaptic-resilience-well-tolerated-alzheimers-patients https://www.nia.nih.gov/news/new-drug-candidate-targeting-sy... https://pmc.ncbi.nlm.nih.gov/articles/PMC8190578/ https://pmc.ncbi.nlm.nih.gov/articles/PMC8190578/ https://www.medicalnewstoday.com/articles/324410 https://www.medicalnewstoday.com/articles/324410 etc.

adastra22 5mo ago
There is lots of neural regeneration in the brain at the cellular level. The science on this is changing quickly. But even though there are new brain cells growing, that does not mean you can reform lost structure.
oneshtein 5mo ago
Lion’s mane mushroom and extracts are used by boxers to repair their brains. But it cannot be patented.
- giantg2 5mo ago
  I'm not sure why this being disagreed to without any response. There are studies related to this out on PubMed. The effects do not seem huge, but they do seem to be significantly better than placebo. And at least those studies are in humans as opposed to the main article of this post that is only in mice.
  - jghn 5mo ago
    I imagine because it reads like one of those "Big Medicine won't let you have access to stuff that works!" conspiracy theories, and also that it won't actually foster new brain cell growth.

deepsun 5mo ago

My understanding is that brain is composed of way more neurons than required, for resiliency. So if it gets a "bruise" in some part, when even a large portion of the cells are dead -- it can still function at 100%. Like a programmer without a finger. The problem is visible only when all the cells in some part are dead. That's why crows, with their low brain mass are pretty clever (and why all arguments equating brain size and smartness are wrong). Just my layman understanding.

sigmoid10 5mo ago
Crows (and certain other bird species) have a peculiar forebrain (different in structure but similar in function/evolution to the neocortex in mammals) with neuron counts rivalling primates. So the nr of neurons still matters, but likely not across the entire brain.
- metalman 5mo ago
  my understanding is that extream migrators actualy consume (use as energy) parts of there own brains durring there epic flights, and other species do something similar in the winter and regrow parts of there brains every spring.
  - sigmoid10 5mo ago
    It is true that they can shrink some organs to reduce weight and store extra fat, but the brain is not one of them. Would be pretty bad, because brain cells can't regrow like e.g. a liver can.
    - metalman 5mo ago
      https://www.sciencedaily.com/releases/2010/04/100429082854.htm https://www.sciencedaily.com/releases/2010/04/100429082854.h...
- deepsun 5mo ago
  Yep. And my point is that too many people seem to judge intellect by brain size or mass. Something like "Neanderthals must've been smarter than Sapiens, because their brains were larger". Or "chimpanzees are smarter than gorillas because gorillas have very small brains", which is all true, except for the word "because" (gorillas are leaf-eaters, so they did not have evolutionary pressure to be smarter, no need in more complex hierarchies, and maybe less proteins for the brain).

rasmus1610 5mo ago

it is more like that the brain learns to use other regions or neurons to do the tasks of the dead brain cells. The brain cells that are dead due to ischemia are dead and will usually be collected by microglia and after some time there are defects in the brain where the ischemia was.

noleary 5mo ago

There've been some interesting new developments in cell therapies over the last few years. Bemdaneprocel from BlueRock Therapeutics is now into Phase 3 trials for Parkinson's, for example. The essential idea is to implant some dopaminergic neuron precursors to grow new cells in place of cell death. Still a long way from the kind of general stroke treatment you're describing, but regenerative neuroscience is looking pretty promising. --- [1] https://www.bluerocktx.com/bluerock-therapeutics-announces-publication-in-nature-of-18-month-data-from-phase-1-clinical-trial-for-bemdaneprocel-an-investigational-cell-therapy-for-parkinsons-disease/ https://www.bluerocktx.com/bluerock-therapeutics-announces-p...