ABSTRACT
OBJECTIVE：To study the hepatotoxicity of main components of Polygonum multiflorum ，and investigate its toxic mechanism based on metabolic enzymes. METHODS ：ADMETlab 2.0 platform was used to forecast the toxic or carcinogenic effects of emodin ，physcion，rhein，stilbene glycoside and gallic acid on liver ，skin and heart. The effects of those components on cytochrome P 450 enzyme system （CYP1A2，CYP2C9，CYP2C19，CYP2D6，CYP3A4）were evaluated. The effects of different concentrations of emodin ，rhein，stilbene glycoside and gallic acid （10，20，40，80 μmol/L）on the survival rate of normal hepatocyte L 02 were detected. The effects of major components of P. multiflorum on the activity of UGT 1A1 enzyme were studied by in vitro reaction system ，using bilirubin as substrate. RESULTS ：Main components of P. multiflorum ，ie. emodin ，physcion， rhein and gallic acid ，showed strong toxic effects on the liver ，while stilbene glycosides possessed weak toxic effects on the liver. Emodin and physcion had strong inhibitory effects on CYP 1A2 and medium inhibitory effects on CYP 2C9，CYP2D6 and CYP3A4；rhein showed medium inhibitory effects on CYP 1A2 and CYP 2C9，while stilbene glycoside and gallic acid possessed weak inhibitory effects on the above enzymes. Emodin （40，80 μmol/L）and gallic acid （40，80 μmol/L）could significantly reduce the survival rate of L 02 cells（P＜0.01）. The inhibition rate of 5，10，20，40，80 μmol/L emodin and gallic acid（except for 5 μmol/L emodin）on UGT 1A1 enzyme increased significantly （P＜0.01），and the inhibition effect of emodin on UGT 1A1 enzyme was reversible competitive inhibition. CONCLUSIONS ：The main components of P. multiflorum ，ie. emodin ，rhein and physcion ， are hepatotoxic ；the mechanism of it may be associated with inhibiting the activity of CYP 1A2 and CYP 2C9 and competitively blocking rate-limiting enzyme UGT 1A1 in the process of bilirubin metabolism.
ABSTRACT
Objective: To establish an HPLC determination method for the quantitative indicators in Qubai granules( stilbene gly-cosides, ferulic acid and paeonol). Methods: A dual-wavelength HPLC assay was used with the following conditions: a chromatogra-phy column ODS (150 mm×4. 6 mm, 5 μm) was used, the mobile phase was methanol: 0. 1% phosphoric acid with gradient elution, the column temperature was 35℃, and the injection volume was 10 μl. Results: The linear ranges of the three active constituents were 1.56-156.00 μg·ml-1(r stilbeneglycoside=0.999 8)、1.00~100.00 μg·ml-1(rferulicacid=0.999 8),1.61~161.00 μg·ml-1(rpaeonol=0. 999 7), respectively, and the average recoveries of the three constituents were between 100. 33% and 100. 76% with the RSDS less than 2% (n=6). Conclusion: The method is simple, stable and reliable, which can be used for the quality control of Qubai granules.
ABSTRACT
Objective:To establish a RP-HPLC method with pre-column derivation for determining the content of stilbene glyco-sides in Yening granules. Methods:DNS-Cl was used as the derivation reagent, a Wondasil-C8 column (250 mm × 4. 6 mm, 5 μm) was used as the stationary phase and 30mM ammonium phosphatere gulation (pH 3. 5)-acetonitrile (78∶22) was applied as the mobile phase, a fluorescence detector (λex=370 nm,λem=560 nm) was used, the flow rate was 1. 0 ml·ml-1 , the column temperature was 30℃ and the injection volume was 20 μl. Results: There was no interference from the other substances in the preparation. The linear range of the two stilbene glycosides was 0.071-27.280 mg·ml-1(r=0.999 9). The average recovery was 99.04%(RSD=0. 1%, n= 9). Conclusion:The method is simple, quick, sensitive and accurate, which can be used for the quality control of Ye-ning granules.