Gout drug compound that blocks bitterness discovered

Many healthy vegetables or medicines have a bitter taste, but it is also something that irks many people especially children.

Although bitterness can sometimes be desirable - such as in the taste of coffee or chocolate - more often bitter taste causes rejection that can interfere with food selection, nutrition and therapeutic compliance.

Now, scientists from the Monell Centre and Integral Molecular have discovered a compound that inhibits bitterness by acting directly on a subset of bitter taste receptors.

"Bitter taste is a major problem for pediatric drug compliance and also for proper nutrition, such as eating those healthy but bitter green vegetables," said Monell senior author Paul Breslin, a sensory biologist.

Bitterness is detected by a family of approximately 25 different taste receptors called TAS2Rs. Together, the TAS2Rs respond to a broad array of structurally different compounds, many of which are found in nature and can be toxic.

In a serendipitous discovery, the researchers found that probenecid, a molecule frequently used in receptor assays, is an inhibitor of a subset of bitter taste receptors. Probenecid also is an FDA-approved therapeutic for gout.

"Probenecid's mechanism of action makes it a useful tool for understanding how bitter receptors function. This knowledge will help us develop more potent bitter taste inhibitors," said Integral Molecular senior author Joseph B Rucker.

A series of human sensory studies established that probenecid robustly inhibited the bitter taste of salicin, a compound that stimulates one of the target receptors.

The study was published in PLoS ONE.