Researchers have discovered a master regulator of inflammation, located in the brain stem, acting akin to a thermostat, finely tuning inflammation levels as needed. Specifically, neurons in the brain stem adjust inflammation in response to signals from the vagus nerve, connecting the brain to other organs. Initially, during infection, these neurons promote a proinflammatory response to combat pathogens. Yet, once the infection resolves, they dampen this response to prevent damage to healthy cells. This feedback system, described in a recent study in mice published in Nature, offers potential insights into regulating inflammation in conditions like autoimmune diseases.
If a similar mechanism exists in humans, it could pave the way for drug development targeting this brain stem regulator. By modulating these neurons, researchers envision the possibility of altering immune modulation and inflammation, potentially benefiting various conditions. Charles Zuker, head of the research team at Columbia University, envisions small molecules that activate these neurons, offering a means to manipulate immune responses.
While prior knowledge hinted at close communication between the brain and the immune system, the brain stem’s role remained unclear. The study sheds light on this by elucidating how the vagus nerve triggers signals to neurons in the caudal nucleus of the solitary tract (cNST) during infection. Stimulating these neurons reduces inflammation, while inhibiting them heightens it, suggesting their pivotal role in regulating the body’s inflammatory response.
Despite these promising findings, many questions linger. Further research is needed to understand the precise nature of signals between the brain stem and immune cells elsewhere in the body. Additionally, scholars emphasize the importance of decoding the brain’s perception of infection and its ability to identify, categorize, or memorize infections for potential future encounters.
