Rhein-8-glucoside is an anthraquinone glycoside that has been found in rhubarb.1 It increases the rate of sennoside A metabolism by mouse intestinal bacteria in vitro when used at concentrations ranging from 0.03 to 1 mM. Rhein-8-glucoside increases the purgative activity of sennoside A in mice in a dose-dependent manner. It also inhibits human protein tyrosine phosphatase (PTP1B; IC50 = 11.5 μM).2 Rhein-8-glucoside is metabolized to rhein by intestinal bacteria.1
|1. Takayama, K., Tsutsumi, H., Ishizu, T., et al. The influence of rhein 8-O-β-D-glucopyranoside on the purgative action of sennoside A from rhubarb in mice. Biol. Pharm. Bull. 35(12), 2204-2208 (2012).|2. Li, S., An, T.-Y., Li, J., et al. PTP1B inhibitors from Saussrurea lappa. J. Asian Nat. Prod. Res. 8(3), 281-286 (2006).