peoniflorin and wogonoside

The pharmacodynamic (PD) and pharmacokinetic (PK) properties of Huangqin Tang (HQT) were investigated in yeast-induced febrile rats. Blood sample and rectal temperature data of the rats were collected at different times after single oral administration of HQT at 20 g x kg(-1). The plasma concentrations of paeoniflorin, baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid were quantified by a sensitive liquid chromatography-tandem mass spectrometric (LC-MS) method. The blood concentrations of PGE2, 1L-1β and TNF-α were detected by radioimmunoassay (RIA). All pharmacokinetic parameters were processed by non-compartmental analysis using WinNonlin software. The potential relationship between the mean concentration of eight constituents and the antifebrile efficacy was investigated by calculating Pearson correlation coefficients. It was found that HQT had significant antifebrile efficacy in yeast-induced febrile rats, but had no effect to normal rats. The antifebrile effect of HQT can be attributed to the inhibition of PGE2, 1L-1β and TNF-α. The constituents (baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid) in febrile rats had delayed absorption and elimination, a longer residence time in the body, and higher C(max) and AUC than those in normal rats. Febrile condition could affect the pharmacokinetic behaviour of HQT in vivo; the flavonoids with the same backbone showed the similar fate in the body; baicalein and wogonin had a strong positive correlation (R > 0.66, P ≤ 0.02) with the antifebrile efficacy determined. Together, these constituents demonstrated different pharmacokinetic properties in the febrile body.

Topics: Administration, Oral; Animals; Area Under Curve; Chromatography, Liquid; Dinoprostone; Drugs, Chinese Herbal; Fever; Flavanones; Flavonoids; Glucosides; Interleukin-1beta; Mass Spectrometry; Monoterpenes; Rats; Tumor Necrosis Factor-alpha

The current study aims to investigate the pharmacokinetic properties of Huangqin Tang on different oral doses. An LC-MS method for simultaneous determination of flavonoids and terpenoids in rat plasma was developed and validated. Plasma samples were treated with hydrochloric acid (containing 1% ascorbic acid), precipitated with acetonitrile, separated on a Zorbax SB-C18 column, detected by single quadruple mass spectrometry with an electrospray ionization interface, and quantified using selected ion monitoring mode. All pharmacokinetic parameters were processed by non-compartmental analysis using WinNonlin software. The results of specificity, linearity, intra-day and inter-day precisions, accuracy, and stability for LC-MS assay were suitable for the quantification of paeoniflorin, baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid in rat plasma. The concentration-time profiles of baicalin, wogonoside, baicalein, wogonin, oroxylin A and glycyrrhizic acid showed double-peak phenomenon after Huangqin Tang was orally administered at 40 g x kg(-1) dose; all eight constituents in rat plasma showed good dose-exposure relationship within the dosage of 10-40 g x kg(-1); although plasma concentrations were different, the flavonoids with the same backbone showed the similar fate in the body with the corresponding dosage. In conclusion, the LC-MS assay was successfully applied for the pharmacokinetic study of multi-constituents of Huangqin Tang with different doses. Additionally, these constituents demonstrated good pharmacokinetic properties in the body.

Topics: Administration, Oral; Animals; Chromatography, Liquid; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Flavanones; Flavonoids; Glucosides; Glycyrrhetinic Acid; Glycyrrhizic Acid; Male; Monoterpenes; Pentacyclic Triterpenes; Rats; Rats, Wistar; Spectrometry, Mass, Electrospray Ionization