Sensory-Guided Multidimensional Exploration of Antisweet Principles from Gymnema sylvestre (Retz) Schult

Abstract

We report on activity-guided investigation of the key antisweet principles of Gymnema sylvestre. Orosensory-guided fractionation by means of solid phase extraction, preparative 2D-LC, and semipreparative HPLC followed by accurate MS and 1D/ 2D NMR experiments revealed six known and three previously unknown gymnemic acids as the key constituents of seven highly sensory-active fractions. Localized via a modified comparative taste dilution analysis (cTDA) and taste modulation probability (TMP) based screening techniques, a strong intrinsic bitterness was also observed for gymnemic acids. In addition, the suppressive effects of the most abundant acids on the response of the human sweet taste receptor to sucrose were verified by means of a functional hTAS1R2/hTAS1R3 sweet taste receptor assay. This in vitro screening revealed large differences in antisweet activity among the isolated compounds, where gymnemic acids XV and XIX showed the highest sweet suppressing activity. This broad-based molecular characterization of the sweet taste inhibiting activity of Gymnema sylvestre will enable further insight into the molecular basis of sweet taste modulation at the receptor level.

Gastrointestinal Interoception in Eating Disorders: Charting a New Path

“…The motilin receptor agonist erythromycin has been shown to induce gastric contractions, hunger signals, and increased food intake [ 81 ], suggesting potential utility as an experimental probe of susceptibility to binge-eating behavior. The blockade of oral sucrose receptors [ 82 ] allows an opportunity to directly examine the influence of sucrose detecting cells in the stomach [ 83 ] in humans, particularly in relation to food cue processing in eating disorders. Finally, acute fasting represents a potent means of naturalistically modulating the strength of neurochemical hunger signaling with direct impacts on interoceptive neurocircuity [ 84 ••].…”