Pharmacokinetics and tissue distribution of 2,3,5,4′-tetrahydroxystilbene-2-O-β-d-glucoside from traditional Chinese medicine Polygonum multiflorum following oral administration to rats

[Display omitted] ► We study pharmacokinetic profiles of a stilbene glycoside of Polygonum multiflorum. ► Adopted RP-HPLC with liquid−liquid extraction method is suitable and reliable. ► Stilbene glycoside in rats is rapidly absorbed into body fluids and rapidly cleared. ► Stilbene glycoside is widely distributed throughout the rat organ tissues. Polygonum multiflorum is an important traditional Chinese medicine used for health promotion and disease treatment. One major bioactive compound in P. multiflorum is a stilbene glycoside (2,3,5,4′-tetrahydroxystilbene-2-O-β-d-glucoside, PM-SG), which possesses antioxidative, anti-inflammatory and endothelial-protective activities. The purpose of the present study was to investigate in vivo pharmacokinetics and tissue distribution of PM-SG after oral administration of Polygonum multiflorum extract to rats by using a reversed-phase high-performance liquid chromatography coupled with liquid–liquid phase extraction. The pharmacokinetic parameters were determined using both compartmental and non-compartmental analyses. All calibration curves for PM-SG in rat plasma and tissues were linear (all r2>0.99) over the range of 0.27–185.00μg/ml. The intra- and inter-day variations were less than 3% at concentration range of 8.7–131.2μg/ml and good overall recoveries (97.7–101.5%) were obtained at the same range. The maximum concentration (Cmax) and the time to reach this concentration (Tmax) of PM-SG were 31.9μg/ml and 40.0min, respectively. The pharmacokinetic profiles estimated by fitting two-compartment and non-compartment models revealed that PM-SG was rapidly absorbed into the body fluids and widely distributed throughout the body, with great efficiency of utility, followed by quick elimination. The highest PM-SG levels were detected in liver and lungs (90.3±20.8μg/g and 86.8±9.0μg/g, respectively) whereas little in brain and testes, indicating PM-SG can hardly penetrate the blood–brain and blood–testicle barriers. This was the first report on the favorable pharmacokinetic profiles of PM-SG in rat plasma and tissues after oral administration. It may provide a meaningful basis for clinical application of such a bioactive compound of herbal medicines.