BMI Seminar // Lukas Van Oudenhove: Small Molecules, Big Impact? Short-chain fatty acids as microbiota-gut-brain axis mediators of human psychophysiology

I will first introduce the concept of humans as holobionts and give an overview of the bidirectional microbiota-gut-brain axis pathways through which the gut and its microbiota can impact brain function. I will then zoom in on the role of the microbial metabolites short-chain fatty acids as key microbiota-gut-brain axis mediators. After briefly introducing their synthesis and local gut effects, I will focus on two of their key properties that may explain their neuroactive effects. First, their role as epigenetic modulators will be highlighted and illustrated with our human data on their impact on stress physiology. Second, their anti-neuroinflammatory effects will be presented. The potential relevance of both these effects for major depressive disorder will be discussed. Finally, new human data on the impact of short-chain fatty acid on GLP-1 and PYY-mediated gut-brain signaling will be shown.