The gut-brain axis, namely, the ways in which nutritional interventions and changes within the gut microbiota can effect cognitive parameters, has become a trending area of research for ingredient developers seeking to target areas such as mood and sleep. Supplementing with a certain bacterial strain, Lactobacillus plantarum PS128, resulted in significant improvements to the severity of depressive symptoms, as well as sleep quality, in people suffering from insomnia, a newly-published study appearing in Nutrients concluded.
 
“The effect of microbiota on the brain occurs through three main pathways of microbiota-gut-brain axis: hormones and neurotransmitters, the immune system, and the vagus nerve,” the authors of the present study said. “One possible approach to actively modulate the gut microbiota to improve health is through probiotics, which are defined as ‘live microorganisms which when administered in adequate amounts confer a health benefit on the host.’” Insomnia, which is estimated to effect anywhere from 10-60% of the population, is also linked to other psychiatric disorders including anxiety and depression.
 
In the study, researchers recruited a pool of 40 participants, all of whom were between the ages of 20 and 40 with self-reported insomnia, who were randomly assigned into either a placebo group or a PS128 experimental group. Both groups were required to self-report depressive symptoms, anxiety symptoms, and sleep quality, while miniature-polysomnography recordings were also taken at the 15^th and 30^th days of the study period.
 
The group who supplemented with two capsules of PS128 showed significant decreases in scores on the Beck Depression Inventory-II scores, fatigue levels, and brainwave activity and awakenings during the deep sleep stage. The improved depressive symptoms among the experimental group also directly correlated with changes in brain waves and sleep maintenance, the authors of the study said. The strain, marketed by Bened Biomed, has been shown in previous human clinical trials to have some beneficial effects on individuals with mental disorders, including autism spectrum disorder (ASD), the authors noted, due to an unknown bio-mechanism which causes dopamine levels to increase upon supplementation.
 
While more studies are needed, the authors concluded that the findings suggest that daily administration of PS128 may lead to a decrease in depressive symptoms, cortical excitation, and fatigue level, along with an improvement in the quality of deep sleep among people experiencing insomnia.