PHILADELPHIA (June 2, 2011) -- 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. This is especially true for children. Now, scientists from the Monell Center and Integral Molecular describe the discovery of 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, Ph.D., a sensory biologist. "But we currently have very limited ways to effectively control bitter taste."
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.
Discovery of bitter blockers would help scientists understand the signaling mechanisms of these receptors and promote the design of novel and more effective blockers.
Monell and Integral Molecular are collaborating on a large project to understand the structure and function of TAS2Rs. 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.
In the study, published in PLoS ONE, a series of in vitro studies revealed that probenecid does not physically block interaction of bitter molecules with the receptor's primary binding site. Rather, it appears to bind elsewhere on the receptor to modulate the receptor's ability to interact with the bitter molecule.
"Probenecid's mechanism of action makes it a useful tool for understanding how bitter receptors function,
|Contact: Leslie Stein|
Monell Chemical Senses Center