Are Probiotics the New Treatment for Stress?


Stress seems fairly inevitable on a day-to-day basis, but the University of Colorado recently conducted a study that links beneficial bacteria to long-lasting, anti-inflammatory effects on the brain. These properties help to make the brain more resilient to the physical and behavioral effects of stress.

Stress, the Brain and Probiotics

The immunoregulatory and anti-inflammatory bacteria used was Mycobacterium vaccae (M. vaccae). This bacteria was tested on adult male rats who were experiencing anxiety-like behaviors to see what effects the M. vaccae bacteria would have on the neuroimmune regulation and the stress-induced neuroinflammatory processes.

The adult male rats were immunized three times, approximately one week apart, with a heat-killed preparation of M. vaccae, and then the anti-inflammatory immunophenotype in the hippocampus, a region of the brain that is responsible for modulating cognitive function, were observed and recorded. 

What's the Verdict?

The male rats who received the three injections showed higher levels of the anti-inflammatory protein interleukin-4 (IL4) in the hippocampus. After the immunization took place, these rats experienced lower levels of stress-induced protein, called HMGB1, which is believed to partake in sensitizing the brain to inflammation. 

“We found that in rodents, this particular bacterium, Mycobacterium vaccae, actually shifts the environment in the brain toward an anti-inflammatory state,” explained Matthew Frank, lead author and senior research associate in the Department of Psychology and Neuroscience, in an interview with ScienceBlog.

The Meaning Behind it All

While there is still plenty of research that would need to be conducted to form any concrete conclusions, this research has the potential for helping in numerous ways. If these findings were to be replicated in clinical trials, it could lead to a potentially new treatment for post-traumatic stress disorder (PTSD), anxiety, depression and other mental illnesses.

Plus, with the research showing how the adult male rats were no longer impacted by the brain becoming sensitized in certain stressful situations, it means this immunization, with further research, could assist in treating people who have experienced a trauma, illness or surgery.

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