If you are sad or depressed, it might be because of the bacteria in your gut

Research concerning the bacteria in the intestines is becoming more and more interesting, and the results are more and more fascinating. Thus, it has just been discovered that stomach bacteria can influence behavior such as anxiety or depression. Investigating the connection between bacteria and biological molecules called microRNAs (miRNAs) in the brain.

Researchers at the APC Microbiome Institute discovered a change in a significant number of miRNAs in the brains of mice that had no gut microbes. Those mice raised in sterile bubbles showed anxiety, unsociability and behaved depressed.

Microorganisms appear to affect miRNAs in the amygdala and prefrontal cortex, and changes in miRNAs can affect physiological processes fundamental to central nervous system function and behavioral regulation including anxiety and depression. Dysfunction of miRNAs is believed to be a fundamental factor contributing to stress-related psychiatric disorders, neurodegenerative diseases and abnormalities.

When the mice regained their normal intestinal flora, their behavior returned to normal. They also found that depleting the intestinal flora of adult rats with antibiotics affected some miRNAs

There is already some previous research that has shown that manipulation of microbes in the gut affects anxiety, but this is the first time that these bacteria have been linked to miRNAs in the amygdala and prefrontal cortex. It is now abundantly clear that we need a healthy microbiome for proper miRNA regulation and normal behavior.

Although the mechanism of how gut bacteria affect miRNAs is not yet known, this research opens up many further treatment options.