Gut microbes may become the key to unlocking anxiety

Gut microbes may become the key to unlocking anxiety

A mouse study showed that the genetic part of the anxiety is mediated by the gut microbiome. Anxiety is already the most common mental illness in many countries, including the United States, and the prevalence of anxiety disorders has increased dramatically during the new pandemic. The study, led by researchers in the field of biological sciences at Berkeley Labs and published in Scientific Reports, provides evidence that taking care of our gut microbiome may help alleviate some anxiety.

The team used a gene heterogeneous mouse line tale called Collaborative Crossing (CC) to detect links between genes, gut microbial composition, and anxiety behavior. They first classified 445 mice across 30CC strains and classified them into high and low anxiety by their behavior in light/dark box experiments. The light/dark box has two compartments, one transparent, illuminated and the other black, without lighting, connected through an opening. The extent to which rodents’ innate aversion to bright, open spaces, replaces their instinct to explore new environments is roughly equivalent to high (or low) anxiety.

The researchers then conducted a genome-wide association study (GWAS) analysis, comparing high-anxiety and low-anxiety mice, as well as analyzing and comparing the gut microbiome composition of high-anxiety and low-anxiety animals. As a result, they found specific genetic variants associated with anxiety behavior and a family of gut microbes, including host genes that indirectly affect anxiety by regulating the abundance of specific microorganisms in the gut.

“We hope this study will inform future studies to assess anxiety treatments that consider the host genome and microbiome,” said Antoine Snijders, a scientist at the Biological Systems and Engineering Division and co-lead author of the paper.”