Screen astragalosides from Huangqi injections by LC-TOF-MS-based mass defect filtering approach / 中国中药杂志

The samples of Huangqi injection (HI) were analyzed by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-TOF-MS), and both positive and negative ion modes were employed to obtain the LC-TOF-MS analysis information of chemical compounds in HI. Then the mass defect filtering (MDF) approach, which was developed based on the previously published articles, was utilized to rapidly screen the astragalosides from the obtained LC-TOF-MS data. Each screened astragaloside was confirmed by the presence of no less than 2 quasi-molecular ions. All the screened astragalosides were then tentatively assigned according to the parent ion and daughter ion information. Finally, a total of 62 astragalosides were screened and characterized from the HI samples, including 15 new detected ones. The identification results indicated that acetylation, hydrogenation, dehydrogenation, methoxylation and hydration might be the major conversion reactions involved in the formation of the astragalosides. The LC-TOF-MS-based MDF approach was proved to be a feasible and efficient tool to screen the chemical constituents in complex matrices such as herbal medicines.

LC-MS/MS method for determination of tripterine in plasma： pharmacokinetic study in Beagles / 中国中药杂志

To establish a LC-MS/MS method for determination of tripterine in Beagle plasma and study its pharmacokinetics after oral administration of tripterygium tablet. Plasma samples were extracted with dichloromethane and separated on a Phenomenex Luna C₈ (2.0 mm×50 mm, 3 μm) column with methanol-acetonitrile isopropanol(1∶1)-1‰formic acid (15∶55 ∶30) as the mobile phase. Tripterine ([M+H] ⁺, m/z 451.3/201.1) and internal standard prednisolone ([M+H] ⁺, m/z 361.1/147.1) were monitored in multiple reaction monitoring (MRM). The concentration-time curves were simulated by drug and statistic software 1.0 and the pharmacokinetic parameters were calculated. There was a good linear relationship between peak area ratio and concentration of tripterine and internal standard prednisolone within range of 0.680 0-136.0 μg•L⁻¹. The limit of quantitation was 0.680 0 μg•L⁻¹ and the intra- and inter-day precision was within 6.15%. The absolute recovery rate was between 50.42% to 51.65%. The concentration-time curves were consistent with the one-compartment model(w=1/cc). The main pharmacokinetic parameters after a single dose were as follows： Cmax (35.64±9.540) μg •L⁻¹,Tmax(2.62±0.69) h,T1/2(2.93±0.29) h, CL (0.308±0.056) L•kg⁻¹•h⁻¹, AUC0-12 (131.16±31.94) μg•L•h⁻¹, AUC0-∞ (142.83±37.57) μg•L•h⁻¹. The established LC-MS/MS method was proved to be sensitive, accurate and convenient, suitable for the pharmacokinetic study of Tripterygium tablet in Beagle dogs.

Study on biomarker of Tripterygium wilfordii in treatment of rheumatoid arthritis based on PK/PD / 中国中药杂志

To observe the serum samples and the anti-inflammatory effect of Tripterygium wilfordii in treating RA by using the pharmacokinetic-pharmacodynamic model, make a correlation analysis on concentration-time and effect-time curves, and explore RORγt, IL-17, STAT3, IL-6 mRNA transcriptional levels in rats by PCR. Methotrexate, tripterine and high-dose T. wilfordii could down-regulate RORγt, IL-17, STAT3, IL-6 mRNA transcriptional levels in AA rat lymph nodes. The study on PK-PD model showed correlations between inflammatory factors and blood concentration of T. wilfordii. T. wilfordii and its main active constituent tripterine could show the inflammatory effect and treat RA by inhibiting IL-17 cytokine.

Analysis of isorhamnetin-3-O-neohesperidoside in rat plasma by liquid chromatography/electrospray ionization tandem mass spectrometry and its application to pharmacokinetic studies / 中国天然药物

AIM@#To establish an LC-MS/MS method for determination of isorhamnetin-3-O-neohesperidoside and investigate its application on pharmacokinetic study in rats.@*METHODS@#Eight rats were given 5 mg·kg(-1) isorhamnetin-3-O-neohesperidoside after intravenous administration. A highly sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of isorhamnetin-3-O-neohesperidosidein rat plasma using rutin as internal standard. The analytes and rutin (internal standard) were extracted with methanol followed by a rapid isocratic elution with 10 mmol·L(-1) ammonium acetate buffer/methanol (20 : 80, V/V) on a C18 column (150 mm × 2.1 mm, I.D., 5 μm) and subsequent analysis by mass spectrometry in the multi-eaction-monitoring mode.@*RESULTS@#The assays were linear over the concentration range of 0.01-10 μg·mL(-1) for isorhamnetin-3-O-neohesperidosidein rat plasma. The lower limit of quantifications for isorhamnetin-3-O-neohesperidoside was 0.01 μg·mL(-1).@*CONCLUSION@#The validated method is successfully applied to determine the plasma concentrations of isorhamnetin-3-O-neohesperidosidein in rats.

Study on determination of caffeic acid, chlorogenic acid in rat plasma and their pharmacokinetics with LC-MS/MS / 中国中药杂志

To establish a LC-MS/MS method to determine caffeic acid, chlorogenic acid in rat plasma and study their pharmacokinetics in rats. Six Sprague-Dawley rats were intravenously injected with 4 mL x kg(-1) of Dengzhanxixin injection, respectively. Their drug plasma concentration was determined by LC-MS/MS, with tinidazole as an internal standard. The pharmacokinetic parameters were calculated by DAS 1.0. The linear concentration ranges of caffeic acid, and chlorogenic acid were 2-128 microg x L(-1) (r = 0.998 1) and 3-384 microg x L(-1) (r = 0.998 7), respectively. The methodological test showed conformance to the requirements. The intraday and inter-day variable coefficients were both less than 10.0%, indicating that both of legitimate precise and accuracy were in conformity with the requirements of biological sample analysis. For caffeic acid, the pharmacokinetic parameter t1/2beta AUC0-t, and CL were (130.91 +/- 38.77) min, (4.89 +/- 0.96) mg x min x L(-1) and (0.12 +/- 0.02) L x min(-1) x kg(-1), respectively. For chlorogenic acid, the pharmacokinetic parameter t1/2beta , AUC0-t, and CL were (49.38 +/- 8.85) min, (9.54 +/- 0.95) mg x min x L(-1) and (0.09 +/- 0.003) L x min(-1) x kg(-1), respectively. The LC-MS/MS analysis method established in this study was proved to be so accurate and sensitive that it can be applied to the pharmacokinetic study of caffeic acid and chlorogenic acid.