17/09/2025
BREAKTHROUGH: Researchers at Duke University have discovered a direct neural pathway—termed the “neurobiotic sense”—that links gut microbes to the brain in real time, reshaping how we understand appetite, behavior, and gut–brain communication.
Published in Nature, this study shows that in the mouse colon, specialized cells called neuropods detect the microbial protein flagellin, via the receptor TLR5, triggering release of PYY. This hormone activates vagal neurons, which promptly signal the brain to curb feeding. Mice lacking TLR5 in those neuropod cells continued to overeat and gained weight.
This mechanism illustrates how gut bacteria, through flagellin detection, can influence behavior on the spot. Importantly, the effect occurs independently of immune activation, metabolism, or overall microbiome presence, and even works in germ-free mice.
The authors propose that this neurobiotic sense may also affect mood and mental health, offering new potential approaches to managing obesity and psychiatric disorders by modulating diet or microbiome composition.
Source: Liu, W. W., Reicher, N., Alway, E., Rupprecht, L. E., Weng, P., Schaefgen, C., … Bohórquez, D. V. (2025). A gut sense for a microbial pattern regulates feeding. Nature.
