Influence of processing on pharmacokinetic of typical constituents in radix polygoni multiflori after oral administration by LC-ESI-MS/MS

Abstract

Ethnopharmacological relevance: The processed radix polygoni multiflori (P-RPM) are produced from the raw radix polygoni multiflori (R-RPM) steamed with black bean juice, but the two traditional Chinese medicines are used to treat the different diseases in clinic. In order to clarify the influence of processing on pharmacological properties of radix polygoni multiflori, an investigation was carried out to compare the pharmacokinetics of typical constituents after oral administration of P-RPM and R-RPM extracts

Materials and methods: A simple, rapid and sensitive high performance liquid chromatography-tandem mass spectroscopy (LC-MS/MS) was developed and validated for the simultaneous determination of gallic acid, polydatin, 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside (PM-SG), resveratrol, and emodin in rat plasma. Male Sprague-Dawley rats were orally administered the two extracts with approximately the same dosage.

Results: It was found that gallic acid was distributed as opened one-compartment model while polydatin, PM-SG and emodin were fitted to an open two-compartment model after oral administration of raw and processed radix polygoni multiflori extract. Cmax and AUC of gallic acid were increased (P<0.01), but Cmax and AUC of PM-SG were descreased (P<0.05). AUC of polydatin and emodin were similar with that of PM-SG. However, resveratrol was not detected in plasma collected at certain intervals following oral administration of the two extracts.

Conclusions: These results indicate that influence of the processing could improve the bioavailability of gallic acid and reduce the absorption of PM-SG, polydatin and emodin in rats. The LC-MS/MS method could be used to evaluate the effect of processing on pharmacokinetic of typical constituents in radix polygoni multiflori after oral administration.