Stomach bypass surgery is sometimes the last resort for those who are struggling with obesity or have serious health problems due to their weight. Because this procedure involves the preparation of a small sac of the stomach, the transformation of the digestive tract, it is very invasive, prolongs the recovery period of patients. In a new study, researchers at Texas A&M University described a medical device that can help with weight loss and require a simpler surgical procedure for implantation.

The researchers noted that their centimeter-sized device provides a feeling of satiety by stimulating light to the extremities of the vagus nerve. Unlike other devices that require a power cord, their device is wireless and can be remotely controlled from a remote radio frequency source.

We wanted to create a device that not only requires minimal surgery for implantation, but also allows you to stimulate specific nerve endings in the stomach. “Our device has the potential to perform both of these operations in severe stomach conditions, which may be of great benefit to people in need of acute weight loss surgery in the future.”

Dr. Sung II Park, Assistant Professor, Department of Electrical and Computer Engineering, A&M University, Texas

Additional details about their device are published in the January issue Nature communications.

Obesity is a worldwide epidemic. Moreover, related health problems have a significant economic impact on the US health care system at a cost of $ 147 billion annually. In addition, obesity puts people at risk for chronic diseases such as diabetes, heart disease and even some cancers. For those who have a body mass index above 35 or have at least two obesity-related illnesses, surgery offers patients not only a way to lose excess weight, but also to maintain long-term weight.

In recent years, the vagus nerve has received a lot of attention in the treatment of obesity, as it provides sensory information about the fullness from the gastric mucosa to the brain. While there are medical devices that can stimulate the extremities of the vagus nerves and, consequently, help suppress hunger, these devices are similar in design to a pacemaker, ie the wires connected to the power supply provide electrical shocks to activate the nerve endings.

However, Park said wireless technologies, such as the use of advanced genetic and optical instruments, have the potential to make nerve stimulation devices more difficult, more comfortable for the patient.

“Despite the clinical benefits of having a wireless system, no device yet has the ability to specifically manipulate chronic ‘long-term’ neuron activity other than the brain,” he said.

To bridge this gap, Park և and his team first used genetic tools to express genes that respond to light at specific nerve endings in vivo in vivo. Then they designed a small shovel-shaped device and placed micro-LEDs near the end of its flexible shaft, which was attached to the stomach. On the head of the device, called the crop, they placed microchips that are needed to communicate wirelessly with the device’s external radio frequency source. The mower was also equipped to generate small currents to power the LEDs. When the radio frequency source was switched on, the researchers showed that LED light was effective in suppressing hunger.

The researchers said they were surprised to find that the biological mechanism that coordinates hunger suppression in their experiments differed from ordinary wisdom. In other words, it is widely accepted that when the stomach fills, it expands, տեղեկատվ information about stretching is transmitted to the brain through the mechanoreceptors of the vagus nerve.

“Our findings show that stimulation of non-stretch receptors that respond to chemicals in food can also cause satiety, even when the stomach is not enlarged,” said Park.

Looking ahead, he said that the current device can be used to manipulate other organs of the gastrointestinal tract, such as the intestines, nerves, with little or no modification.

“Wireless optogenetics, the discovery of peripheral neural pathways that control appetite, and other behaviors are all of great interest to researchers in the major fields of electronics, materials science, and applied neuroscience,” said Park. “Our new tool now allows us to study the function of neurons in the peripheral nervous system in a way that was impossible with existing approaches.”


Magazine link.

Kim, VS, et al. (2021) Organ-specific, multimodal, wireless optoelectronics for the high-throughput phenotype of peripheral neural pathways. Nature communications.