A new way of interpreting inflammatory signals using the vagus nerve — which carries such signals from throughout the body to the brain — has been found, a study reports.
This finding raises the possibility of having a kind of “early warning system” for inflammation, a damaging process in such chronic illnesses as multiple sclerosis (MS), lupus, rheumatoid arthritis, psoriasis, irritable bowel syndrome, and celiac disease.
The research, “Identification of cytokine-specific sensory neural signals by decoding murine vagus nerve activity,” was published in the journal Proceedings of the National Academy of Sciences of the United States of America.
The vagus nerve, the longest of the autonomic nervous system — which controls internal organs and glands — extends from the head to the abdomen, and has both sensory and motor functions. It nerve fibers carry information on the workings and health of such organs such as the heart, esophagus, stomach, pharynx, larynx, and the bowels.
Researchers, with specialties in signal processing and machine learning, used the method to better understand the specific inflammatory responses associated with different diseases.
Working with mice, they found that exposure to TNF and IL-1 beta, two inflammatory molecules, led to different nerve impulses being recorded from the vagus nerve.
“Here we develop methods to isolate and decode specific neural signals to discriminate between two different cytokines,” the study reports. “Nerve impulses recorded from the vagus nerve of mice exposed to IL-1β and TNF were sorted into groups based on their shape and amplitude, and their respective firing rates were computed.”
That allowed the team to detect “signaling that the nervous system uses to communicate immune status and inflammation to the brain,” Theodoros Zanos, PhD, the study’s lead author and a professor at the Feinstein Institute, said in a press release.
It also found that “sensory neural groups [responded] specifically to TNF and IL-1β in a dose-dependent manner,” according to the study.
Zanos said the team will now try to identify neural signaling for diverse medical conditions. “This research is a key step to engineering cutting-edge diagnostics and therapeutics,” he said.
“The goal is to be able to use these nerve signals to infer what is going on in the body and how the brain is attempting to regulate critical systems,” added Peter Lorraine, a researcher at GE Global Research.
If successful, this approach might allow scientists to “monitor therapies directly by looking at how they impact signals from specific organs and how the brain is attempting to respond to those signals,” Lorraine said. According to what is found, they might then “potentially fix problems with the signals themselves due to diseases.”
“We’re just beginning to understand this new language being communicated inside the body. But as we become more fluent, we have the opportunity to see and understand the root causes and earliest stages of inflammation that could enable us to stop it in its tracks before it leads to something more serious,” he concluded.