ABSTRACT
Naoxintong capsule (NXT), a prescribed Chinese medicine, has been used clinically for more than 20 years and is widely received by patients. We determined five probe drugs, namely, omeprazole (CYP2C19), midazolam (CYP3A4), phenacetin (CYP1A2), tolbutamide (CYP2C9), and dextromethorphan (CYP2D6) to study the potential influences of NXT on the activities of CYP enzymes and assessed the pharmacokinetics effect of NXT on metoprolol tartrate in rat plasma. The study showed that AUC(0-24) and AUC(0-∞) of midazolam (CYP3A4) in NXT coadministration group (283.7 ± 65.2 h·ng·mL-1 and 292.0 ± 75.1 h·ng·mL-1 in group B; 295.7 ± 62.7 h·ng·mL-1 and 299.5 ± 60.0 h·ng·mL-1 in group C) were significantly decreased as compared to another group (416.8 ± 82.3 h·ng·mL-1 and 424.9 ± 77.9 h·ng·mL-1 in group A), while that of dextromethorphan (CYP2D6) showed an opposite tendency (540.7 ± 119.7 h·ng·mL-1 and 595.3 ± 122.2 h·ng·mL-1 in group A, 760.6 ± 184.9 h·ng·mL-1 and 788.7 ± 211.0 h·ng·mL-1 in group B, and 734.3 ± 118.5 h·ng·mL-1 and 757.2 ± 105.4 h·ng·mL-1 in group C). Moreover, NXT preadministration can enhance the metabolism of metoprolol tartrate and reduce the metabolism of O-demethylmetoprolol. The results indicated that NXT had potential effects in inducing CYP3A4 and inhibiting CYP2D6 in the metabolism of metoprolol tartrate. It suggests that patients who coadministered NXT and metoprolol tartrate should be advised of potential herb-drug interactions (HDIs) to reduce therapeutic failure or accelerated toxicity of conventional drug treatment.
ABSTRACT
A sensitive and reliable LC-MS/MS method has been developed and validated for simultaneous determination of six Aconitum alkaloids (aconitine, hypaconitine, mesaconitine, benzoylaconitine, benzoylhypacoitine, and benzoylmesaconine) and seven ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, and Rg1) in rat plasma after oral administration of Shen-Fu prescription. Psoralen was selected as internal standard (IS). Protein precipitation with methanol was used in sample preparation. The chromatographic separation was achieved on a CORTECS™ C18 column with 0.1% formic acid aqueous solution and acetonitrile as mobile phase. The flow rate was 0.3 mL/min. The detection was performed on a tandem mass system with an electrospray ionization (ESI) source in the positive ionization and multiple-reaction monitoring (MRM) mode. The calibration curves of six Aconitum alkaloids and seven ginsenosides were linear over the range of 0.1-50 and 1-500 ng/mL, respectively. The extraction recoveries of the analytes in plasma samples ranged from 64.2 to 94.1%. Meanwhile, the intra- and interday precision of the analytes were less than 14.3%, and the accuracy was in the range of -14.2% to 9.8%. The developed method was successfully applied to the pharmacokinetics of six Aconitum alkaloids and seven ginsenosides in rat plasma after oral administration of Shen-Fu prescription.
ABSTRACT
Periplocin is a cardiac glycoside and has been used widely in the clinic for its cardiotonic, anti-inflammatory and anti-tumor effects. Although it is taken frequently by oral administration in the clinic, there have been no reports demonstrating that periplocin could be detected in vivo after an oral administration, so there is an urgen need to determine the characteristics of periplocin in vivo after oral administration. In this study, a sensitive and reliable liquid chromatography-tandem mass spectrometry method was developed and validated to identify and quantify periplocin and its two metabolites in rat tissue after a single dosage of perplocin at 50 mg/kg. The results demonstrated that periplocin and its two metabolites were detected in all of the selected tissues; periplocin could reach peak concentration quickly after administration, while periplocymarin and periplogenin reached maximum concentration > 4.83 h after administration. The tissue distribution of analytes tended to be mostly in the liver, and higher analyte concentrations were found in the heart, liver, spleen, lung and kidney, but a small amount of chemical constituents was distributed into the brain. The consequences obtained using this method might provide a meaningful insight for clinical investigations and applications.
