CANBERRA, March 26 (Xinhua) -- A study led by scientists in Australia has uncovered a gut-brain pathway governing how parasitic infections lead to nausea, appetite loss and other sickness symptoms.
A team from the South Australian Health and Medical Research Institute (SAHMRI) and Adelaide University, working with U.S. and Chinese collaborators, found that two specialized gut cell types coordinate to sense parasites and activate protective responses through the vagus nerve, a SAHMRI statement said Thursday.
The findings fill a major gap in understanding how the body senses and responds to gut infections, said Prof. Stuart Brierley, director of the visceral pain research group at SAHMRI and co-senior author on the study published in Nature.
"We know parasite infections make people feel unwell, lose their appetite and change their behavior, but the exact communication pathway from the gut to the brain has been a mystery until now," Brierley said.
"We've shown that tuft cells act as the first detectors. They release acetylcholine, which pushes EC (Enterochromaffin) cells to release serotonin, and that serotonin is what drives the nerve signals that tell the brain something is wrong," he said.
The sustained signaling drives a much stronger serotonin response from EC cells, activating vagal neurons that turn off appetite and ramp up nausea, the study said.
By identifying the exact cell types and neurotransmitters involved, researchers now have a clear pathway that could be targeted to reduce nausea, improve appetite or modulate gut-brain signaling in a range of disorders. ■
