Taking the probiotic microorganism Bifidobacterium longum reduces physiological and psychological stress and leads to a moderate improvement in memory - these data were demonstrated in a small pilot study conducted with healthy men.

The results of the study were presented in October 2015 at the annual conference of the Society for Neuroscience (SfN).

This study was based on the results of a preclinical study in which the strain B. longum was identified as a "suspected psychobiotic" having a positive effect on behavioral aspects related to stress, physiological moments. and cognitive function in mice.

A new concept of the key role of the intestinal microbiota in the regulation of brain function and behavior is a revolution in neurophysiology. Exposure to the gut-microbiome-brain system using psychobiotics (ie, living microorganisms with potentially beneficial mental health properties) is a new approach to managing patients with stress.

In a new study, 22 healthy men (mean age 25.5 years) received B. longum NCIMB 41676 daily for 4 weeks and placebo for the next 4 weeks.

At the start of the study and after 4 weeks of probiotic or placebo treatment, the researchers assessed the acute stress (subjective data and cortisol synthesis) using a cold pressure test and a daily assessment of the stress using a validated online questionnaire (Cohen Perceived Stress Scale). Cognitive status was assessed using the Cambridge Neuropsychological Test automated battery, neurological activity - based on electroencephalography (EEG).

In response to acute stress, the use of B. longum NCIMB 41676 has led to a decrease in the cumulative release of the stress hormone cortisol, as well as a decrease in the severity of the subjective feeling of irritability. According to the questionnaire, study participants reported moments of less pronounced stress and irritability while taking a probiotic. In addition, a slight improvement in the visual memory test results as well as in the EEG data after reception of the probiotic has also been demonstrated.

Researchers note that more research is needed to assess the beneficial properties of this putative psychobiotic for stress-related conditions and to decipher the mechanisms underlying these effects.

Currently, more and more attention is paid to the importance of the interaction between the intestinal microbiota and the brain. A clear understanding of the mechanisms of this relationship can provide physicians with a new strategy for the prevention and treatment of many psychological problems.