Link Clarified Between Gut Microbes and Emotions

February 12, 2018 · Posted in Neurobiology · Comment 

mice exercising

A 2017 article in the journal Microbiome suggests that gene-regulating molecules called microRNAs in the brain may be the link between microbes in the gut and emotions.
The research by Alan E. Hoban and colleagues looked at mice raised in a sterile, microbe-free environment. These mice had fewer anxiety-like behaviors than mice raised among the usual bacteria, viruses, and fungi. This finding implies that the microbiome—the trillions of microbes that live in and around our bodies—affects brain functions. In this case, the affected regions were the prefrontal cortex and the amygdala, which both play a role in the detection and response to fearful stimuli. These regions showed alterations in the level of microRNAs present.

When Hoban and colleagues introduced microbes into the animal’s systems, some microRNAs did not bounce back, suggesting that there may be a crucial window early in life when the presence of microbes is needed for the brain to develop normally.

In general, this research shows that microRNAs are key to understanding the link between the microbiome and the brain.