2025 Canada winner

Disorders of gut–brain interaction, such as irritable bowel syndrome and functional dyspepsia, are very common and are often made worse by psychological stress. Many patients report that a stressful period is followed by long-lasting bowel changes, pain, and fatigue, yet current treatments rarely address how stress alters the gut environment itself or the microbes that live there.

The inner surface of the intestine is lined by a thin barrier that must do two things at once: protect the body from harmful contents in the gut and continually renew itself to stay healthy. Our recent work shows that chronic stress can make this barrier thinner and “leakier,” disturb its natural ability to protect and renew, and shift the gut microbiota away from more favourable communities. These stress-induced changes in microbes and barrier function appear to reinforce each other, creating a vicious cycle that may sustain symptoms.

This project will investigate how chronic stress reshapes the gut microbiota and their products, and how these changes weaken gut barrier protection and renewal. Using established stress models, we will map microbiota and metabolite shifts and measure their impact on barrier integrity. We will then look for similar “stress–microbiota–barrier” signatures in people with stress-aggravated gut symptoms using stool microbiome profiling and non-invasive tests of barrier function. Finally, we will test microbiota-targeted and stress-modulating strategies in experimental systems to see whether we can restore a healthier microbial ecosystem and rebuild the gut barrier. The long-term goal is to provide a foundation for future microbiota-based and barrier-protective therapies that improve quality of life for people living with stress-related gut disorders.

2 Questions to Dr. Xiaopeng Bai

What inspired you to pursue this specific research project?

In my clinical practice, I often see patients whose gut symptoms reliably worsen during periods of sustained psychological stress. We talk about stress as a trigger all the time, but we still lack a clear biological explanation for how stress translates into lasting changes in gut function.

This project grew out of that gap, together with our preliminary observations that chronic stress can reshape the gut microbiota and alter the epithelial stem-cell program that maintains barrier renewal. I want to understand that connection in a mechanistic way, because if we can identify the key microbial and epithelial pathways involved, we can begin to design strategies that protect the barrier and reduce symptom flares.

How will the Biocodex Microbiota Foundation Grant support contribute to the success and advancement of your research?

This grant is a catalyst at a pivotal stage of the work. It will allow us to carry out the core experiments needed to move from association to mechanism, linking stress-related microbiota changes to measurable effects on epithelial stem-cell function and barrier integrity.

Practically, the support will help us generate the proof-of-principle and high-quality preliminary data required to accelerate the project, support trainees and key assays, and position the program for larger follow-on funding and clinical translation. This is exactly the type of focused support that helps a project launch with momentum and produce results quickly.