Promoting a healthy gut by influencing metabolic activity 

We recently published three pioneering articles on how probiotics directly influence the functioning of the gut microbiota. In collaboration with our academic partners, we have examined the effects of probiotics not only within the colon, but also in unexplored regions such as the small intestine. Here’s what we discovered: 

Probiotics can boost lactate production

The first one, that we conducted in collaboration with the University of Reading is part of a larger project focussing on cognition. We explored how probiotics influence the production of microbial metabolites in the large intestine. First of all, we were able to demonstrate that bacteria in the intestines do indeed produce crucial neurotransmitters such as GABA, serotonin, tryptophan, and dopamine. These neurotransmitters play an important role in gut-brain communication. Furthermore, we found that certain probiotic strains (Lc. Lactis and L. rhamnosus) positively impact lactate production. Hence, by reducing pH levels, these probiotic strains possess the ability to inhibit the colonization of potential pathogens within the gut. This means that, even without shifting the microbiota composition, probiotic bacteria can influence metabolic activity.  

Discovering impact on the small intestine

 The other two studies, that we conducted in collaboration with the University of Groningen delved into the interactions between probiotics and the small intestine’s microbiota. The small intestine is known as a critical area for nutrient absorption and immune system interactions.
Due to the limited accessibility for research, the way probiotics interact with the microbiota in the small intestine is not very well understood.  To address this, we constructed a synthetic community of three species, which resembles the upper small intestinal microbiota. Next, we introduced specific probiotic strains into this small intestinal ecosystem. Notably, the introduction of Streptococcus thermophilus triggered a surge in lactate production while driving down pH levels. The addition of Lactobacillus casei sparked a remarkable improvement in stability. These findings illuminate the potent ability of distinct probiotic strains to directly affect the metabolism of the small intestinal community.  

Using stoma effluent as a model: counteracting pathogens 

In this study, we used a revolutionary method to study the effects of probiotics on the upper small intestinal microbiota. What makes this study stand out is that by utilizing stoma effluent from ileostomy patients, we recreated conditions similar to the in-vivo small intestine. In this controlled environment, we introduced a blend of probiotic strains. Adding probiotics improved the connections within the network of microorganisms in the gut. This in turn, gave rise to the following effects: 

Effective pathogen control 

The probiotics showed impressive potential by effectively countering the growth of two bacterial families, Enterococcaceae and Enterobacteriaceae, both known to contain gut pathogens.  

Improved  resistance to disturbances 

Metabolites regarded as negative, like ethanol, were significantly reduced. On the other hand, beneficial metabolites, like short chain fatty acids were increased. This has profound implications for nutrient utilization and the gut’s ability to withstand disturbances. 

In conclusion, these three studies underscore the significance of not only examining the composition but also the functional aspects of the gut microbiota. The discovered mechanisms help in preventing gastrointestinal issues and infections.  

Do you want to know more about these studies or our (pre) clinical and mechanistic work? Please reach out to our team, we are happy to get in touch with you.