
Glial brain cells, long in neurons’ shadow, reveal hidden powers - theafh
https://www.quantamagazine.org/glial-brain-cells-long-in-neurons-shadow-reveal-hidden-powers-20200127/
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Fishysoup
We've known for at least a decade that astrocytes and other glia play
important roles in synaptic transmission and learning, not just axon
insulation and blood-brain-barrier related stuff. It's still unclear what most
of their contributions are. They're harder to interrogate because they're not
as electrically active as neurons, and though they do exhibit Calcium waves,
they're small and seem to be localized to small compartments. There's a number
of people out there working on glia in a functional sense, like Atwell at UCL
and Magistretti (though he's retired now i think).

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api
We've known even longer than that:

[https://en.wikipedia.org/wiki/Tripartite_synapse](https://en.wikipedia.org/wiki/Tripartite_synapse)

Earliest references are from the late 1990s.

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Fishysoup
Oh wow didn't know it went back that early, nice

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jedberg
In elementary school I had to do a report on Einstein, and I remember one of
the important details was that he had a higher ratio of glial cells to neurons
than a normal brain.

At the time, they had no idea if this made any difference to his genius, and
it sounds like they still aren't too sure.

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reasonattlm
One of those hidden powers is the destruction of the aging brain. Senescence
of glial cells appears to be quite important in the progression of
neurodegeneration, as both a source of neuroinflammation and all of its woes,
and a mechanism capable of more directly causing neuron death.

Clearance of senescent glial cells prevents tau-dependent pathology and
cognitive decline -
[https://doi.org/10.1038/s41586-018-0543-y](https://doi.org/10.1038/s41586-018-0543-y)

Tau protein aggregation is associated with cellular senescence in the brain -
[https://doi.org/10.1111/acel.12840](https://doi.org/10.1111/acel.12840)

Flushing out 'zombie cells' could help stave off Parkinson's, study suggests -
[https://www.theguardian.com/science/2018/jan/23/flushing-
out...](https://www.theguardian.com/science/2018/jan/23/flushing-out-zombie-
cells-could-help-stave-off-parkinsons-study-suggests)

Astrocyte senescence: Evidence and significance -
[https://doi.org/10.1111/acel.12937](https://doi.org/10.1111/acel.12937)

The good news here is that the senolytic drug dasatinib crosses the blood-
brain barrier and has been demonstrated to destroy senescent glial cells in
animal models, and destroy senescent cells elsewhere in the body in human
trials. The cheap dasatinib / quercetin combination should be trialed in
Alzheimer's and Parkinson's patients, and the sooner the better.

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IIAOPSW
I used to have fun trolling by saying "we only think with 10% of our brains".
Then as soon as someone comes in thinking they were about to school me real
good, I'd drop the fact that 90% of our brains aren't neurons but merely glial
support structures so the statistic is technically true. The ol' double cross
in pedantic trivia.

I guess I need to stop doing that now.

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dwaltrip
I think the latest research indicates that glial cells are about as numerous
as neurons (the article says something to this effect as well), so the joke
would update to "we only use half of our brains".

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neural_thing
Went to a conference a couple of years ago where there was an interesting talk
on the subject. See here if you are interested:

[https://vimeo.com/262522684](https://vimeo.com/262522684)

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ickelbawd
Does this mean the connectome is doomed or faulty since it maps only neurons
and not glial cells?

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GliaApostle
I wouldn't say that. I'm on a team that's doing reconstruction: glia are
included. Astrocytes have a massive surface area, so their meshes are harder
to analyze, but we have them along with oligodendrocytes and some possible
microglia.

I would caution that the connectome is like the human genome. Both are very
useful, but both came with a lot of hype that it would solve everything. We
have connectomes for things like C. Elegans and we're still unsure about
neuronal computations within them.

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DoctorOetker
Could the glial cells be somehow responsible for backpropagation in the brain?

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nshm
Brain doesn't do backpropagation

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DailyHN
> Brain doesn't do backpropagation

What makes you so sure?

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Sommer
If it did I would have learned from my mistakes.

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short_sells_poo
He could have overfit due to his training size being too small. Either he has
to add some noise or increase his set.

