In vivo and in vitro study on characterization and mechanism of the intestinal absorption of 2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside
Abstract Background: 2,3,5,4'-tetrahydroxystilbence-2-O-β-D-glucoside(TSG) is a polyhydroxyphenolic compound, which exhibits a broad spectrum of pharmacological activities, such asanti-inflammatory, anti-depression, anti-oxidation and anti-atherosclerosis.However, the compound has poor bioavailability and the underlying absorption mechanisms has not been studied. Therefore, the purpose of this study was to investigate the intestinal absorption mechanism of TSG. Methods: This study used the Caco-2 cell monolayer model and the single-passintestinal perfusion modelto explore the intestinal absorption mechanisms of TSG. The effects of basic parameters such as drug concentration, time and pH on the intestinal absorption of TSG were analyzed by high performance liquid chromatography.In addition, the susceptibility of TSG absorption process to treatment with three inhibitors, such as P-gp inhibitors verapamil hydrochloride and quinidine, and the MRP2 inhibitor probenecid were also assessed. Results: TSG is poorly absorbed in the intestines and the absorption of TSG in the stomach is much higher than that in the intestine. Both in vivo and in vitro experiments showed that the absorption of TSG was saturated with increasing concentration. and it was better absorbed in a weakly acidic environment with a pH of 6.4. Moreover, TSG interacts with P-gp and MRP2, and TSG is not only the substrate of the P-gp and MRP2, but also affects the expression of P-gp and MRP2. Conclusions: It can be concluded that the intestinal absorption mechanismsofTSG involve processes passive transport and the participation of efflux transporters.