Physical activity sensitizes vagal gut-brain communication underlying feeding control

Despite an overall increase in caloric needs, regular physical activity has been associated with improved appetite signaling. The neurobiological mechanisms underlying this sensitization remain unclear. We employed a voluntary wheel running protocol to investigate how physical activity affects gut-brain communication of vagal sensory neurons for the control of feeding behavior in mice. We find that physically active mice exhibit a significant decrease in food intake in response to the delivery of nutrients directly into the stomach, as compared to sedentary controls. Further, sensitivity to cholecystokinin (CCK), a gut-derived satiation factor, is increased in physically active mice. Because CCK’s appetite-suppressing action is known to be mediated by vagal sensory neurons, we currently analyze vagal gut-brain neurocircuits by employing genetic profiling, as well as manipulation and imaging techniques. Together, our results will provide new insights into modulatory role of gut-brain communication pathways in appetite regulation and may provide new targets for body weight control.