An entirely new way of treating inflammatory diseases could open up thanks to the discovery that gut inflammation can be blocked in mice simply by stimulating a particular nerve.
Wouter de Jonge’s team at the University of Amsterdam Academic Medical Center in the Netherlands applied tiny, painless electric shocks to the vagus nerve, which runs down through the neck to the gut and elsewhere, during abdominal surgery on mice. The treatment prevented a form of severe gut inflammation known as post-operative ileus.The team has shown that the effect is caused by the neurotransmitter acetylcholine. When it is released by the vagus nerve, it binds to receptors on any macrophages near the nerve endings, preventing the immune cells from triggering inflammation (Nature Immunology, DOI: 10.1038/ni1229). “We’ve established the exact mechanism by which macrophages react to neurotransmitters,” says de Jonge. The results also add to growing evidence that the nervous system can affect the immune system.Although implants exist for stimulating the vagus nerve to treat epilepsy and depression, de Jonge thinks it would be easier to treat gut inflammation by designing drugs that mimic the effect through stimulating the receptors on macrophages.(Source: New Scientist magazine; issue 2509; 23 July 2005; page 16.)