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Enhancing gut-brain communication reversed cognitive decline in aging mice

med.stanford.edu

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Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#81

Post by idiotsecant »

bitexploder wrote: post #60
inanutshellus wrote: post #9

Everyone's "poo-pooing" the article because the title doesn't mention mice, but, FWIW, stories of gut biota affecting humans behavior have been documented for a while. Memory gain is noteworthy, which is the article's "wow" factor, but everyone's just knee-jerk smirking so ... here's a few random articles to gross you out about the wild world of trading microbiota and, for better or worse, changing your personality:…

Most of the serotonin we produce comes from our gut.

The blood brain barrier is a deny by default firewall. If there is no transporter configured for a particular molecule, it doesn't get through. There is no transporter for serotonin

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#82

Post by bitexploder »

Aurornis wrote: post #64
bitexploder wrote: post #60

Earlier quoted context omitted.

Most of the serotonin we produce comes from our gut.

Serotonin produced in the gut doesn’t get into your brain. This factoid is repeated everywhere but it’s misleading without knowing that gut serotonin is a different pool than brain serotonin and they have different functions. The brain synthesizes its serotonin locally within the brain.

Serotonin from the gut affects vagal neurons. They carry that signal directly to the brain. That has a significant effect on up and down regulation of mood and arousal.

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#83

Post by mustaphah »

Aurornis wrote: post #70
mustaphah wrote: post #14

Yeah, it's a mouse study, but there are tons of human studies backing the whole gut-brain connection. There are even a bunch of books on it [1][2]. What's really cool is that the paper used low-dose capsaicin (just 5 μg/kg injected), and it completely restored hippocampal FOS activity and memory in older mice. Basically, that's the same stuff you get in cayenne pepper supplements - pretty easy to get your hands on. […

> What's really cool is that the paper used low-dose capsaicin (just 5 μg/kg injected), and it completely restored hippocampal FOS activity and memory in older mice. There are countless papers published where simple ingredients produce miracles in mice. Most of them don’t replicate. If you look up most food ingredients you can find someone, somewhere claiming to have used it to produce amazing outcomes in mice. After…

> After you read a lot of those you learn not to take individual papers seriously

Can't disagree, but keep in mind that almost all meds are tested first in mice/animal models before human trials verify the effects.

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#84

Post by bitexploder »

idiotsecant wrote: post #81
bitexploder wrote: post #60

Earlier quoted context omitted.

Most of the serotonin we produce comes from our gut.

The blood brain barrier is a deny by default firewall. If there is no transporter configured for a particular molecule, it doesn't get through. There is no transporter for serotonin

See: vagal neurons and vagus nerve. Serotonin from gut directly impacts those. Your brain still directly interprets that signal from the vagus nerve and uses that to up and down regulate mood and arousal. Impact is still significant

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#85

Post by asdff »

1shooner wrote: post #11
inanutshellus wrote: post #9

Everyone's "poo-pooing" the article because the title doesn't mention mice, but, FWIW, stories of gut biota affecting humans behavior have been documented for a while. Memory gain is noteworthy, which is the article's "wow" factor, but everyone's just knee-jerk smirking so ... here's a few random articles to gross you out about the wild world of trading microbiota and, for better or worse, changing your personality:…

This seems to be a recent anti-science meme to dismiss studies that use mouse models. I'm sure there is an interesting line of discussion about the strengths and limits of those models, but that's probably a complex, nuanced thread to pull, not something you blow off with a hand-waving internet comment.

I wish I could filter the word mice or mouse out of hn comments because as you say every single one are low effort gotcha's that I will never get my time back from.

It is like these armchair scientists don't understand that the actual scientists know the limits of the model system better than they do.

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#86

Post by throwawaytwit9 »

reverius42 wrote: post #73
throwawaytwit9 wrote: post #59

Earlier quoted context omitted.

It may not work for you but I had years of chronic heartburn. While sick with covid in 2020, I stopped consuming coffee and alcohol. It took a few months and for the long covid symptoms to subside, and then no more heartburn. At all. I felt really dumb that I never connected it to coffee before. I didn’t experience direct symptoms from coffee and I didn’t consume an excess amount. But it definitely was the cause.

I'm a couple weeks into giving up coffee because of heartburn, and yeah, this tracks... unfortunately. I've replaced heartburn with heartache (having given up a beverage I've enjoyed daily for over 20 years).

Good luck, my friend. I’m right there with you. It’s not the physical effects but the rituals and the social connections that I miss. I felt the same with coffee as I did with smoking, which I quit about 20 years ago. It’s remarkable how much these simple vice shape our daily lives.

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#88

Post by systemsweird »

slibhb wrote: post #46
inanutshellus wrote: post #9

Everyone's "poo-pooing" the article because the title doesn't mention mice, but, FWIW, stories of gut biota affecting humans behavior have been documented for a while. Memory gain is noteworthy, which is the article's "wow" factor, but everyone's just knee-jerk smirking so ... here's a few random articles to gross you out about the wild world of trading microbiota and, for better or worse, changing your personality:…

In my opinion, gut microbiome stuff is massively overhyped. Here's a study that tried fecal transplants to treat mental illness (and found no effect): https://pubmed.ncbi.nlm.nih.gov/41785480/ The pattern with this stuff is that, when a blinded study is carried out, there's usually no effect.

I think mainstream is mostly looking at the microbiome stuff wrong. Your microbiome is the downstream proxy of good lifestyle habits, not generally something to directly manage. Good diet, exercise, reducing stress, and sleeping well will improve digestion and all the downstream variables like microbiome, physical health, and mental health.

This is basic ecology, the bacterial population dynamics in your colon are a direct result of substrate availability. If it’s primarily fiber, polyphenols, and other indigestible plant compounds reaching the colon you’ll likely have a healthy microbiome. If instead you malabsorb food from poor lifestyle factors and have macronutrients reaching the colon they’ll probably fuel blooms of pathogens. I think microbiome researchers need to talk with ecologists more to help advance the field out of the myopia it’s in.

FMT does appear useful for special cases of infection like c-diff, but I think that’s led people to believe it’s a generally health promoting practice, when the research simply does not show it.

Re: Enhancing gut-brain communication reversed cognitive decline in aging mice

#90

Post by systemsweird »

Aurornis wrote: post #69
butILoveLife wrote: post #48

Earlier quoted context omitted.

You are probably right on the specifics, but serotonin is produced/located in the gut, and its an incredibly important neurotransmitter. One day people will figure out how to use these correctly.

> but serotonin is produced/located in the gut, and its an incredibly important neurotransmitter. Serotonin in the gut doesn’t go to your brain. It serves a different function in the gut. The brain synthesizes serotonin inside of the brain. It doesn’t come from your gut.

Thanks for following up with a correction. This is a myth that simply refuses to die. I cannot even count the number of times I’ve heard people repeating it.
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