A new battery-free, implantable weight-loss device developed by engineers at the University of Wisconsin-Madison could be humanity’s newest weapon in the battle against obesity.
Measuring less than a centimeter across, the tiny device — which scientists claim is safe for use in the body and implantable via a minimally invasive procedure — generates gentle electric pulses from the stomach’s natural churning motions and delivers them to the vagus nerve, which links the brain and the stomach. These signals trick the brain into thinking the stomach is full after only a few nibbles.
In the laboratory, the device has helped mice shed 40 percent of their bodyweight.
“The pulses correlate with the stomach’s motions, enhancing a natural response to help control food intake,” says Xudong Wang, a UW-Madison professor of materials science and engineering.
This technology could be a preferable alternative to the gastric bypass procedure, which permanently reduces the stomach’s food capacity. The effects of this device are completely reversible. When Wang and his team removed the devices from rats after 12 weeks, they resumed their normal eating patterns and their weight returned to what it was previously.
However, this is not the first technology of its kind. In 2015 the United States Food and Drug Administration approved a device called “Maestro”, which delivers high frequency zaps to the vagus nerve which shuts down communication between the brain and the stomach. However, it comes with a complicated control unit and requires charging.
Luke Funk, a surgery professor in UW-Madison’s Division of Minimally Invasive, Foregut and Bariatric Surgery has called these maintenance requirements a major barrier, which makes Wang’s device superior.
“One potential advantage of the new device over existing vagus nerve stimulators is that it does not require external battery charging, which is a significant advantage when you consider the inconvenience that patients experience when having to charge a battery multiple times a week for an hour or so,” said Funk.
Wang’s device contains no batteries, no electronics, and no tedious wiring. It relies on the undulations of the stomach walls to power its internal generator. This means the device only stimulates the vagus nerve when the stomach walls move.
“It’s automatically responsive to our body function, producing stimulation when needed,” says Wang. “Our body knows best.”
Wang and his team have already patented the weight-loss device through the Wisconsin Alumni Research Foundation and are moving forward with testing in larger animal models. If this batch of tests is successful, they plan on moving onto human trials.