Stimulating a vagus nerve can tame autoimmune diseases – a public radio in South Carolina

Small impulses of electricity can provide the next major progress in the treatment of diseases such as rheumatoid arthritis.

The impulses will be delivered through implanted devices that stimulate the vagus nerve and they show a promise in people with arthritis and other autoimmune diseases, including Crohn’s and multiple sclerosis.

Autoimmune diseases are currently usually treated with drugs that suppress the immune system. Some of these drugs are given by infusion and can cost tens of thousands of dollars a year. They also increase the risk of a person from infection.

Stimulating the vagus nerve can offer a way to increase or replace drug treatment, doctors say.

“Neural signals have the ability to reflexively control aspects of the immune system, which is honest, no one has thought before,” says Dr. Kevin Tracy, president of the Institutes of Medical Research in Northwell, Long Island.

Tracey is the co -founder of Setpoint Medical, a company that hopes to launch a vagus nerve stimulating system for autoimmune diseases.

It is not yet clear whether stimulation of the vagus nerve will be as effective as drug treatment, says Dr. Andrew Co, a neurosurgeon at the University of Washington in Seattle, who implanted setting stimulators in patients with rheumatoid arthritis as part of a study.

“Medicines work, but sometimes they don’t and you can have side effects,” Co says. “In these cases, there are some benefits to viewing devices.”

KO notes that implanted vagus nerve stimulants have already been approved for certain patients with epilepsy and depression. Devices that stimulate people’s brain with Parkinson’s disease have proven to be “better than drugs” when symptoms are reduced, he says.

Rheumatoid arthritis, which affects about 1.5 million people in the United States, is ready to become the first autoimmune disease treated with electrical impulses sent through the vagus nerve.

A device made by Setpoint Medical is reviewed by the US Food and Drug Administration, which is likely to decide by the end of 2025.

The agency’s review will include 2024 survey of 242 patients. It finds that 12 weeks stimulation with the device significantly reduce both symptoms and progression of the disease. Also, damage to their joints has occurred more slowly and levels of inflammatory proteins have fallen dramatically.

Wandering nerve that connects the brain and body

The connection of the vagus nerve to the immune system was discovered accidentally more than 20 years ago.

Kevin Tracy of Northwell and a team of researchers gave rats an experimental medicine designed to prevent inflammation in the brain. To their surprise, she also suppressed the inflammation in the body.

The reason was a signal sent from the brain to the body’s immune system.

“We have learned that the signal is traveling on the vagus nerve and the vagus nerve is like the brake lines in your car,” says Tracy. “These were the brakes of inflammation.”

Tracy says that the realization has led to the question: “Can we make devices that include the brakes and then treat patients with excessive inflammation?”

It will take decades of research to make this happen.

The vagus nerve is actually a pair of nerves, right and left, which connect the brain to the internal organs, including the heart, lungs, liver, intestines and spleen.

“This is the only nerve in your body, if you cut it on both sides, you die,” says Tracy.

Much of modern vagus nerve studies have been done at the Institute of Bioelectron Medicine of Feincetein, one of the institutes that Tracy controls. Dr. Stavros Zaganna is responsible for a team that maps the human vagus nerve, which is often compared to the signals for carrying a superhah path throughout the torso.

During a tour of its laboratory, Zanos holds a transparent tube containing a leg or so of white fabric similar to a cord, a little thinner than a pencil.

“This is the greater part of the vagus nerve from the brain to the neck up to half the distance through the chest,” he says.

He then shows me what a cross section looks like under a microscope.

“It’s like a cucumber slice,” he says. “You see all these small green spots, thousands and thousands of them? These are separate fibers.”

Right and left vague nerve packages have more than 100,000 of these threads.

“Many fibers inform the brain of the inflammatory state of the whole body,” Zanosa says.

Researchers from Feincetein eavesdrop on these fibers in animals and have even developed a system that turns the vagus trafficking in audio in real time.

This allows them to hear how inflammation in the body changes the signals that go into the brain.

Sangeeta Chavan plays a recording from an experiment. At first there is a constant throm after the rhythm of the heart rate and breathing, but when researchers inject a substance that causes inflammation, the sound becomes like popcorn released into hot oil.

“When inflammation occurs, the molecules activate signals that travel up the vague nerve,” Tracy says.

And that’s just half a story.

Electrical impulses activate a reflex that causes the brain to produce another set of signals that travel back on the vague nerve.

These are the brake signals, the Tracy team opened for decades earlier. They reduce the immune system so that the inflammation does not go out of control.

The signals do this by telling certain immune cells to stop producing inflammatory proteins called cytokines.

“What we have found is that vague nerve signals exclude the production of cytokines in the spleen,” an organ that plays a major role in the immune response.

Next, the Tracy team learned how to stimulate the vagus nerve in a way that activates the anti -inflammatory reflex.

This allowed Setpoint Medical to develop a device to stimulate implant implantation.

“It’s about the size of a big pill, a really big multivitamin,” Co says, adding that it is similar to the Nervous stimulants approved by the FDA, it implants in patients with epilepsy.

Setpoint is already looking beyond patients with rheumatoid arthritis. The company has started testing of its stimulating device in patients with multiple sclerosis and Crohn’s disease.

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