Gut-targeted therapies for type 2 diabetes mellitus: A review

Table 1 Representative implanted electronic devices in the intestine for the treatment of type 2 diabetes mellitus

Patent/product name	The main ways to exert curative effect	Core functional/structural features	Ref.
Electroporation for obesity or diabetes treatment	Cause weight loss or control diabetes by reducing the caloric absorption by increasing levels of gut hormones important in appetite regulation and insulin secretion, and/or by reshaping the mucosa of the small intestine	The device can provide an electroporation treatment to modulate the duodenal mucosa, which can also be advanced over a guide wire under endoscopic and/or fluoroscopic guidance	[9]
Devices and methods for endolumenal gastrointestinal bypass	The devices can mimic a Roux-en-Y gastric bypass by effectively reducing stomach volume, bypassing a portion of the stomach and/or small intestine, reducing nutrient absorption in the stomach and/or small intestine	The device can be utilized to support a variety of devices which may be desirably positioned within the stomach or elsewhere in the gastrointestinal system	[10]
Methods and systems for glucose regulation	Up-regulation or down-regulation of various nerves, such as the vagus and its branches. The splanchnic nerve is used to modify the production of GLP-1 and GIP, thereby controlling glucose levels	Applying a neural conduction block to a target nerve at a blocking site with the neural conduction block selected to at least partially block nerve pulses	[11]
Treatments for diabetes mellitus and obesity	The stimulation by high-frequency alternating current is selective in blocking slow-conducting, unmyelinated C-fibers, such as those of nociceptive neurons, while minimizing effects on fast-conducting myelinated A-fibers	The ablation may be mechanical, electrical, thermal, radiative, or chemical ablation and may in some cases target a sensory nerve. In highly preferred embodiments, the ablation is a pulsed radiofrequency ablation	[12]
Methods and systems for blocking neural activity in an organ of a subject, preferably in the small intestine or the duodenum	In preferred embodiments, the invention is directed at endoluminal interventions that block, modulate and/or impact neurohormonal and other signals triggered by food passing through the gastrointestinal tract	Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by applying electromagnetic radiation, e.g. microwaves using lasers, the beam being directed along or through a flexible conduit, e.g. an optical fiber	[13]

GLP-1: Glucagon-like peptide-1; GIP: Glucose-dependent insulinotropic polypeptide.