FLASH: New ingestible electrode capsule to stimulate hunger-regulating hormone

The development of this new capsule

FLASH is an acronym for electronic fluid-wicking capsule for active stimulation and hormone modulation. The water-wicking skin of the thorny devil lizard inspired the design of this capsule. It is a non-invasive and safe therapy that delivers treatment directly to the stomach tissues. 

This capsule was designed in this study to work on "neuromodulation of the gut-brain axis, the signaling pathway between the gastrointestinal tract and the central nervous system." Simply put, the gut-brain axis is important for the regulation of physiological functions such as feeding and emotional behavior. 

This FLASH system has an electrode-coated surface that connects directly to mucosal tissue in the gut. This causes an electrical sensation in the stomach, which is known as gastric electrical stimulation (GES). This entire process is responsible for the release of the hunger hormone ghrelin.  

By ingesting orally, it was seen that the pill was able to regulate the levels of ghrelin significantly. The findings revealed that electronically stimulated hunger hormones had little effect on the body's surroundings. It is also excreted safely without causing any side effects in the body. 

Alternative methods for regulating the gut-brain axis are mostly surgical and include the implantation of electrodes. However, these methods are risky and may prolong recovery time.

“As far as we know, this is the first example of using electrical stimuli through an ingestible device to increase endogenous levels of hormones in the body, like ghrelin. And so, it has this effect of utilizing the body's own systems rather than introducing external agents,” Ramadi added in a press statement.

Helpful in the treatment of gastrointestinal diseases

Furthermore, the innovative capsules are powered by ingestible batteries, allowing for 20 minutes of stimulation. The capsule was tested in pig models, where the researchers discovered that ghrelin levels were increased in stomach tissues with intact vagus nerves. 

This entire medical treatment is based on a technique known as neuromodulation, which alters specific nerve activity. In this case, it's the vagus nerve, which is our body's longest autonomic nervous system nerve, connecting the brain and the gut. And this nerve performs a variety of functions, including digestion.

This precise method could be useful in regulating hunger levels as well as treating metabolic, gastrointestinal, and neurological diseases. Furthermore, the therapy may be used to treat diseases associated with nausea or loss of appetite, such as cachexia and gastroparesis, which is a disorder of the stomach nerves that causes slow food movement. 

“We show one example of how we're able to engage with the stomach mucosa and release hormones, and we anticipate that this could be used in other sites in the GI tract that we haven’t explored here,” said Giovanni Traverso, the senior author of the study.

The results have been published in the journal Science Robotics.