Newly Discovered 'Sixth Sense' Connects Gut Microbes to the Brain in Real Time

Recent scientific advances have unveiled a novel communication mechanism between our gut microbiome and the brain, termed a 'neurobiotic sense.' Researchers from Duke University have identified a system that enables the brain to respond instantly to signals emitted by microbes residing in the gastrointestinal tract.

Led by neuroscientists Diego Bohórquez, Ph.D., and M. Maya Kaelberer, Ph.D., the study, published in Nature, focuses on specialized cells called neuropods located in the colon lining. These tiny sensors detect a common microbial protein—bacterial flagellin—and transmit rapid messages to the brain, influencing appetite regulation.

Flagellin, a protein found in bacterial flagella used for bacterial movement, is released by gut bacteria during digestion. Through the receptor TLR5 on neuropods, this protein triggers neural signals via the vagus nerve, a primary pathway connecting the gut and brain.

Experimental studies involving fasting mice demonstrated that administering flagellin directly into the colon resulted in decreased food intake. Conversely, mice lacking the TLR5 receptor did not exhibit these responses, implying that flagellin's interaction with TLR5 is essential for conveying 'satiety' signals.

This discovery suggests that microbes can influence behavior through rapid neural pathways, not just immune or inflammatory responses. The findings open promising avenues for understanding how diet and microbiota composition impact eating habits, mood, and possibly mental health conditions.

The research team envisions that the 'neurobiotic sense' could be a broader platform for studying microbe-brain interactions. Future research aims to explore how dietary interventions alter the microbial landscape and affect behaviors associated with obesity and psychiatric disorders.

Source: MedicalXpress