According to a recent global survey reported in the New England Journal of Medicine, in which scientists analyzed the data from 68.5 million people between 1980 and 2015, over 710 million people worldwide are plagued by obesity problems. This number includes 107.7 million children and 603.7 million adults. Researchers also reported that some 4 million people died of overweight- or obesity-related diseases in 2015.
And according to the Centers for Disease Control and Prevention (CDC) National Center for Health Statistics (NCHS) data brief, in America in 2015 and 2016, some 43% of middle-aged adults (ages 40 to 59 years), and 41% of older adults (aged 60 and older) were obese. https://www.cdc.gov/nchs/data/databriefs/db288.pdf
But University of Wisconsin-Madison scientists believe they may have come up with a way to stem the tide of obesity-related disease and illness and improve quality of life for hundreds of millions of people worldwide who suffer from weight problems. These scientists have created what they say is a safe and easily implantable weight-loss device that in lab experiments, aided rats in shedding nearly 40% of their body weight.
The battery-free device, measuring less than a centimeter, generates gentle electric pulses from the stomach’s natural churning motions and sends them to the vagus nerve, which links the brain and stomach. This stimulation tricks the brain into thinking the stomach is full after a minimal amount of food has been consumed.
“In vivo vagus nerve stimulation holds great promise in regulating food intake for obesity treatment,” lead authors, Guang Yao and Lei Kang of the University of Wisconsin-Madison, reported in their study. Yao and Kang represent the Department of Materials Science and Engineering and the Department of Radiology, respectively. Their study was published this month in the international science journal Nature. “Here we present an implanted vagus nerve stimulation system that is battery-free and spontaneously responsive to stomach movement. The vagus nerve stimulation system comprises a flexible and biocompatible nanogenerator that is attached on the surface of stomach. It generates biphasic electric pulses in response to the peristalsis of stomach. The electric signals generated by this device can stimulate the vagal afferent fibers to reduce food intake and achieve weight control.”
Within 100 days of exposure to the device, researchers said the average body weight of rats used in the experiment had lost 38% of their body weight as compared to the control groups. “This work correlates nerve stimulation with targeted organ functionality through a smart, self-responsive system, and demonstrated highly effective weight control,” researchers reported. “This work also provides a concept in therapeutic technology using artificial nerve signal generated from coordinated body activities.”
Common non-surgical and surgical treatments for treating obesity till now have included daily physical exercise; weight-loss drugs; and bariatric surgical procedures such as gastric bypass, biliopancreatic diversion and sleeve gastrectomy. But weight-loss drugs often have side effects as well as a high probability of weight rebound. And while available surgical approaches have demonstrated a significant impact on weight loss, they are invasive and carry with them the potential of serious complications.
Researchers said recent breakthroughs in neuromodulation for weight control have created the possibility for more effective and less invasive treatment options for obesity. “The rising healthcare standards demand new obesity treatment strategies that are effective, easy to operate, and have less side effects,” researchers reported. “Neuromodulation, as a non-destructive and reversible therapeutic strategy, can manipulate body functions by stimulating or influencing neurophysiological signals through the neural networks to achieve therapeutic purpose. It has been known for a century that the vagus nerve…acts as a signal bridge to transport information between the brain (the center of the nervous system) and the body (head, neck, thorax, and abdomen). Recent breakthroughs in neuromodulation for body weight control have provided potential opportunities for therapeutic interventions and brought renewed promises and vitality to the development of new anti-obesity strategies.”
Researches went on to say that a number of studies have already demonstrated that pulsed electrical stimulations on vagus nerve can induce multiple physiologic functions related to food intake, energy metabolism and glycemic control, all of which can result in appreciable weight loss. An implantable vagus nerve stimulation (VNS) device for weight control, Maestro, was approved in 2015 by the U.S. Food and Drug Administration (FDA) and commercialized. That device administers high-frequency pulses to the vagus nerve to turn off all communication between the brain and stomach and requires a cumbersome control unit and batteries that require frequent recharging.
In fact, the new device contains no batteries, no electronics, and no complicated wiring. It relies solely on the fluctuations of the stomach walls to power its internal generators and only stimulates the vagus nerve when the stomach moves. And unlike gastric bypass, the effects of the new device are completely reversible.
“Our correlated VNS system demonstrates outstanding weight control results, which largely outperformed other reported chronic microchip VNS systems based on similar rat models,” the authors reported. “In addition, this correlated VNS is battery free and less invasive compared to the bariatric surgical strategies (e.g., gastric bypass, biliopancreatic diversion or sleeve gastrectomy) for weight control.”
Scientists are looking at adding a switch to control the treatment in future clinical trials. “This could be achieved by integrating a shutter switch to the electrical wires from the VNS device, as it has been proved that a disconnected device has no impact to food intake and weight change.”