Master regulator of inflammation found — and it's in the brain stem

Scientists have found a master regulator of iNFLaMMAtion — and it's in the brain stem. 

New research in mice has revealed that the neurons in the brain stem act like a thermostat, ramping up or down inflammation in response to signals sent by the vagus nerve, which connects the brain to other organs in the body. 

In the early stages of an infection, these neurons might encourage a helpful, proiNFLaMMAtory response to thwart invading pathogens. However, once an infection is cleared, the neurons tamp down this response to prevent unwanted damage to Healthy cells. Researchers described this feedback system in a new study published May 1 in the journal Nature. 

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If a similar feedback loop is found in humans, scientists could one day identify drugs that regulate it. For instance, drugs that target this brain stem thermostat could be used to reduce inflammation in diseases where it goes out of whack, such as autoimmune diseases, the researchers said. 

"If we can come up with small molecules that go into these neurons and turn them on, now you may have a way of regulating the circuit and therefore changing the way they are modulating body immunity and the inflammatory state," Charles Zuker, head of the laboratory where the study was carried out and a professor of biochemistry, molecular biophysics and neuroscience at Columbia University, told Live Science. 

The brain stem connects the main part of the brain, the cerebrum, to the cerebellum and the spinal cord, and it regulates key involuntary functions such as breathing and heart rate. Researchers already knew that the brain and the immune system communicate closely with one another, but the role of the brain stem in that process wasn't clear.