Sweet Guts


To everyone's surprise three years ago, scientists discovered our sugar receptors aren't exclusive to the tongue. Our guts can sense sweetness too – the stomach, intestine, pancreas, and even our airways.

Scientists got pretty excited about what this meant for diabetics. Could drugs target these receptors to help people with type 2 diabetes? This is the most common form of diabetes when the body no longer makes enough insulin or stops responding to it. We need insulin for our cells to take up the glucose in our blood and use it for energy.

One drug, called New-Met is promising. It's now in phase two clinical trials and targets receptors in the intestine. New-Met binds to sweet receptors there, activating the release of incretins. Incretins stimulate the release of insulin which then allows our cells to take up sugar in the blood. This mimics the natural signaling process triggered by sugars and it's fast and direct.

Discovering this signaling process in the intestine cleared up a fifty year mystery: how eating glucose triggers significantly more insulin than injecting it directly into the bloodstream. When the sweet receptors in the intestine detect sugar they trigger adjacent cells to make a glucose transporter to take the sugar into cells. The faster the sugar is absorbed, the more signals are sent to the pancreas and more insulin is released.

Thus, understanding these alternative taste receptors can help us develop effective therapies. New-Met will also help the four million diabetics in the US who can't take metformin, the leading type-2 diabetes drug. As the number of Americans with diabetes climbs to six million, the demand for additional medications will rise with them.

More Information

Neuroscience: Hardwired for taste
Nature —A mouthful of bittersweet chocolate cake with a molten centre can trigger potent memories of pleasure, lust and even love. But all it takes is one bad oyster to make you steer clear of this mollusc for life. Neuroscientists who study taste are just beginning to understand how and why the interaction of a few molecules on your tongue can trigger innate behaviours or intense memories.

Elcelyx 'Guts' Conventional Thinking on Metformin
BioWorld —A San Diego biotech with eight employees grabbed the spotlight at the American Diabetes Association (ADA) Scientific Sessions in Chicago with the revelation that Type II diabetes drug metformin acts in the lower bowel, not in the bloodstream.

Metformin in the treatment of adults with type 2 diabetes mellitus
UpToDate — Two classes of oral hypoglycemic drugs directly improve insulin action: biguanides (only metformin is currently available) and thiazolidinediones (TZDs). In the absence of contraindications, metformin is considered the first choice for oral treatment of type 2 diabetes (table 1). A 2006 consensus statement from the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD), updated in 2009 and 2012, proposed that metformin therapy (in the absence of contraindications) be initiated, concurrent with lifestyle intervention, at the time of diabetes diagnosis [1-3].