Bitter substances from plants used in traditional Bitter substances from plants used in traditional Chinese medicine exert biased activation of human bitter taste receptors

Chem Biol Drug Des. 2017 Aug 21. doi: 10.1111/cbdd.13089. [Epub ahead of print] Behrens M1, Gu M2, Fan S2, Huang C2, Meyerhof W1. Author information 1 German Institute of Human Nutrition Potsdam-Rehbruecke, Dept. Molecular Genetics, Nuthetal, Germany. 2 Shanghai University of Traditional Chinese Medicine, School of Pharmacy, Drug Discovery Lab, Shanghai, China. Abstract The number and variety of bitter compounds originating from plants is vast. Whereas some bitter chemicals are toxic and should not be ingested, other compounds exhibit health beneficial effects, which is manifest in the cross-cultural believe that the bitterness of medicine is correlated with the desired medicinal activity. The bitter taste receptors in the oral cavity serve as sensors for bitter compounds and, since they are expressed in numerous extraoral tissues throughout the body, may also be responsible for some physiological effects exerted by bitter compounds. Chinese herbal medicine uses bitter herbs since ancient times for the treatment of various diseases, however, the routes by which these herbs modify physiology are frequently not well understood. We therefore screened 26 bitter substances extracted from medical herbs for the activation of the 25 human bitter taste receptors. We identified 6 receptors activated by in total 17 different bitter compounds. Interestingly, we observed a bias in bitter taste receptor activation with 10 newly identified agonists for the broadly tuned receptor TAS2R46, 7 agonists activating the TAS2R14 and 2 compounds activating narrowly tuned receptors, suggesting that these receptors play dominant roles in the evaluation and perhaps physiological activities of Chinese herbal medicines. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved. KEYWORDS: G protein-coupled receptors; TAS2R; bitter taste receptor; herbal extract; traditional Chinese medicine PMID: 28834122 DOI: 10.1111/cbdd.13089