[Research] Normal Gut Microbiota Modulates Brain Development and Behavior

[RobinN]

Abstract

Microbial colonization of mammals is an evolution-driven process that modulate host physiology, many of which are associated with immunity and nutrient intake. Here, we report that colonization by gut microbiota impacts mammalian brain development and subsequent adult behavior. Using measures of motor activity and anxiety-like behavior, we demonstrate that germ free (GF) mice display increased motor activity and reduced anxiety, compared with specific pathogen free (SPF) mice with a normal gut microbiota. This behavioral phenotype is associated with altered expression of genes known to be involved in second messenger pathways and synaptic long-term potentiation in brain regions implicated in motor control and anxiety-like behavior. GF mice exposed to gut microbiota early in life display similar characteristics as SPF mice, including reduced expression of PSD-95 and synaptophysin in the striatum. Hence, our results suggest that the microbial colonization process initiates signaling mechanisms that affect neuronal circuits involved in motor control and anxiety behavior.


http://www.pnas.org/content/108/7/3047

 

[Chaz1]

"Germ free"

Just wondering how that’s achievable for many.....hmm

Interesting, survival of fittest...

 

[Silat]

This is... really strange and unexpected....
Thanks for sharing!

 

[RobinN]

Chaz... might GF be lacking the live viruses introduced into the gut?

 

[epileric]

First off, I don't see how GF have any relevance to viruses.

Also, the abstract was edited (and not by the authors) which I found odd considering an abstract is a short summary.

Edited by Arturo Zychlinsky, Max Planck

I therefore found the actual study. http://www.pnas.org/content/108/7/3047.full.pdf Their sample sizes ranged from 4-15. Even at 15 that isn’t very much to get excited about. Anyone that's studied statistics knows that anything less than 30 doesn't really mean anything except maybe it should be done with more subjects.

Also, they detected increased neural activity but that doesn't mean smarter or better cognition nor do they claim it does. After all a seizure is increased neural activity.

They never looked for any other changes in the mice or anything else that might have caused the changes. Also they used different types of tests for each sample of mice and when things are not done consistently it can create problems.

The main thing though is that they didn’t speculate on what it might mean or infer and drew no conclusions which means it’s totally experimental & they are not making any claims regarding the implications of their results or neural activity.

 

[Bernard]

Researchers often do not get tons of funding for full scale studies when the goal is a new or unproven/untested hypothesis/theory. The way the process works is that small scale studies are done first and if the data supports it, larger scale studies follow.

 

[epileric]

Researchers often do not get tons of funding for full scale studies when the goal is a new or unproven/untested hypothesis/theory. The way the process works is that small scale studies are done first and if the data supports it, larger scale studies follow.

That's very true but looking for other changes in the study and keeping test types consistent are not related to financial issues.

Also, as interesting as it is, they make no statement as to what the results might imply and why. Assuming it implies anything is just that.... an assumption.