Scientists have developed a ground-breaking ingestible capsule that artificially creates a feeling of fullness in the stomach, perhaps leading to people eating less and losing weight. The ingestible capsule vibrates within the stomach, fooling the stretch receptors into thinking the stomach is already full. When the stomach dilates, specialized cells called mechanoreceptors sense the stretching and send signals to the brain via the vagus nerve.
As a result, the brain begins to produce insulin and other hormones such as C-peptide, Pyy, and GLP-1. These hormones work together to aid digestion, generate a sense of fullness, and regulate eating cessation. Simultaneously, ghrelin levels, a hormone that encourages hunger, fall. The researchers demonstrated in an animal study that when the vibrating pill is triggered, it activates mechanoreceptors, which send messages to the brain via vagus nerve stimulation. Hormone levels measured during vibrating intervals resembled patterns observed following a meal, even in fasting animals.
Animals given the vibrating pill gained weight at a slower rate
The researchers looked at how this stimulation affected the animals’ hunger. When compared to periods when the pill was inactive, activating the pill for approximately 20 minutes before giving food resulted in an average 40% reduction in food consumption. Furthermore, animals given the vibrating pill gained weight at a slower rate. “For somebody who wants to lose weight or control their appetite, it could be taken before each meal,” says Shriya Srinivasan PhD ’20, a former MIT graduate student and postdoc who is now an assistant professor of bioengineering at Harvard University. “This could be interesting in that it would provide an option that could minimize the side effects that we see with the other pharmacological treatments out there.”
“The behavioural change is profound, and that’s using the endogenous system rather than any exogenous therapeutic. We have the potential to overcome some of the challenges and costs associated with delivery of biologic drugs by modulating the enteric nervous system,” Giovanni Traverso, an associate professor of mechanical engineering, at MIT. The researchers now plan to explore ways to scale up the manufacturing of the capsules, which could enable clinical trials in humans.