Determination of vericiguat in rat plasma by UPLC-MS/MS and its application to drug interaction.

Vericiguat (VER) is a novel soluble guanylate cyclase stimulator treating symptomatic chronic heart failure (HF), and it is a substrate of both transporters P-glycoprotein and breast cancer resistance protein (BCRP). Astragaloside IV (ASIV) is the main active ingredient in Radix Astragali (Huangqi), a traditional Chinese medicine widely used for HF treatment in China. ASIV's effect on the protein expression of P-glycoprotein and BCRP has been observed, its impact on VER metabolism remain uncertain. In the present study, male Sprague-Dawley rats were administered with 20 mg/kg ASIV and 1 mg/kg VER to study their pharmacokinetics. Blood samples were subject to liquid-liquid extraction, and riociguat was employed as the internal standard (IS). The analytical method involved a C18 column (XSelect® HSS T3 column, 2.1 × 100 mm, 2.5 µm) with a mobile phase of 0.1% formic acid and acetonitrile for gradient elution. The flow rate of the mobile phase was set at 0.2 mL/min, and 5 µL of the sample was used for analysis. The positive ion multi-response monitoring mode was utilized with a transition of m/z 427.4→109.1 for VER and m/z 423.3→109.1 for the IS. The method exhibited good linearity within the concentration range of 0.1 to 300 ng/mL (r = 0.9987), and all the validation processes were conducted in accordance with the requirements of biological analysis. The pharmacokinetic results revealed that ASIV did not significantly alter the main parameters of VER, except for Cmax, which decreased by 33.2% (P < 0.05). Overall, our study successfully established a selective, sensitive and repeatable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis for detecting VER in rat plasma.

QiShenYiQi pills, a Chinese patent medicine, increase bioavailability of atorvastatin by inhibiting Mrp2 expression in rats.

CONTEXT: Atorvastatin (ATV) and QiShenYiQi pills (QSYQ), a Chinese patent medicine, are often co-prescribed to Chinese cardiovascular patients. The effects of QSYQ on the pharmacokinetics of ATV have not been studied. OBJECTIVE: We investigated the influence of QSYQ on the pharmacokinetics of ATV and its metabolites upon oral or intravenous administration of ATV to rats. MATERIALS AND METHODS: Sprague-Dawley rats (n = 5/group) were pre-treated with oral QSYQ (675 mg/kg) or vehicle control for 7 days and then orally administrated ATV (10 mg/kg) or intravenously administrated ATV (2 mg/kg). Serum concentrations of ATV and metabolites were determined by ultra-high performance liquid chromatography tandem mass spectrometry. Expression of metabolic enzymes and transporters in jejunum and ileum were measured by quantitative real-time PCR and Western blot. RESULTS: QSYQ resulted in an increase of AUC0-12 h of ATV from 226.67 ± 42.11 to 408.70 ± 161.75 ng/mL/h and of Cmax of ATV from 101.46 ± 26.18 to 198.00 ± 51.69 ng/mL and in an increased of para-hydroxy atorvastatin from 9.07 ± 6.20 to 23.10 ± 8.70 ng/mL in rats administered ATV orally. No change was observed in rats treated intravenously. The expression of multidrug resistance-associated protein 2 mRNA and protein decreased in ileum, and the mRNA of P-glycoprotein decreased in jejunum, though no change in protein expression was found. DISCUSSION AND CONCLUSIONS: QSYQ increased bioavailability of ATV administered orally through inhibiting the expression of Mrp2 in ileum. Clinicians should pay close attention to potential drug-drug interactions between ATV and QSYQ.

UPLC-MS/MS method for the determination of Lenvatinib in rat plasma and its application to drug-drug interaction studies.

Lenvatinib (LEN) is a multitargeted tyrosine kinase inhibitor registered for the first-line treatment of unresectable advanced hepatocellular carcinoma. Wuzhi capsule (WZC) is a traditional Chinese medicine preparation; it is used to decrease the aminotransferase level of the liver and protect liver function. Thus, patients with hepatocellular carcinoma (HCC) are potentially treated with a combination of LEN and WZC, but there is no information about the interaction between the two drugs. We developed a simple, rapid, and sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the quantitative determination of lenvatinib in rat plasma. Liquid-liquid extraction of plasma samples was carried out with ethyl acetate. Chromatographic separation of analyte was performed using gradient elution with acetonitrile and 0.1% formic acid water. The positive ion multi-response monitoring mode was used, and the target of the parent and daughter ions of LEN and IS were m/z 427.1→370 and m/z 432.1→370, respectively. All the validation projects were in accordance with the guidelines. Good linearity of 0.2-1000 ng/mL (r > 0.999) was achieved. The lower limit of quantification was 0.2 ng/mL. The precision and accuracy are acceptable. The method was successfully applied to pharmacokinetics and drug interaction analysis. The results show that WZC can significantly increase the Cmax (maximum plasma concentration) and AUC (area under the concentration-time curve) of LEN. An UPLC -MS/MS method that can be used for studying drug-drug interaction as a valuable tool was developed in this study. Drug-drug interactions were observed between the WZC and LEN.

Application of hollow fiber centrifugal ultrafiltrate purification as the pretreatment technology for traditional Chinese medicine: its application for analysis of honokiol and magnolol in TCM preparations containing Cortex Magnoliae Officinalis.

BACKGROUND: Traditional Chinese medicine (TCM) preparations are very complex mixtures, and the content of bioactive components is usually very low. Therefore, before final analysis, the preparation of an appropriate sample is necessary. Sample preparation is the most time-consuming and error-prone part of the analytical procedure, and the choice of purification technology greatly influences the reliability of the final analysis. METHODS: In the present study, we evaluated the feasibility of hollow fiber centrifugal ultrafiltrate (HFCF-UF) as a purification technology for the analysis of bioactive components in TCM preparations. The HFCF-UF technology was applied to analyze honokiol and magnolol in TCM preparations containing Cortex Magnoliae Officinalis (Hou Po in Chinese Pinyin). A mini centrifugal device based on hollow fiber was employed to remove the macromolecule components. A single step of simple centrifugation was required before the filtrate could be directly injected into an existing high performance liquid chromatography (HPLC) system without any further clean-up step or use of special columns. This greatly simplified the pretreatment steps, and improved the accuracy of analytic methods. The separation was achieved on a Diamonsil C18 column (i.d. 5 µm, 150 mm × 4.6 mm) with V (methanol):V (acetonitrile):V (0.5% acetic acid solution) =44:22:34 as the mobile phase at a flow rate of 1.0 mL/min. RESULTS: It had good linear relationship between the peak areas of honokiol and magnolol and their concentrations at 6.40-205 and 3.15-101 µg/mL (r=0.9999), respectively. The method recovery was over 92.6% with a relative standard deviation (RSD) of less than 3.0%. The average recovery of honokiol was 97.7% with an RSD of 3.0%, and that of magnolol was 96.8% with RSD of 2.8%. CONCLUSIONS: The application of HFCF-UF in TCM preparations could assist in making the quality control of TCM simple, rapid, and accurate. The HFCF-UF purification procedure can be used as an alternative means for analyzing bioactive components in TCM preparations.

Compound danshen dripping pills affect the pharmacokinetics of azisartan by regulating the expression of cytochrome P450 2B1, 2C6, and 2C11 in rats.

Combination therapies of compound danshen dripping pill (CDDP) and Azilsartan (AZ) represent a promising treatment option in clinical practice in China, but there are no reports on drug-drug interactions between CDDP and AZ. This study investigated the effects of CDDP on the pharmacokinetics of AZ and clarified its potential mechanism. The pharmacokinetic profiles of oral administration of AZ (2 mg/kg) in Sprague-Dawley rats, with or without pre-treatment of CDDP (81, 405, 810 mg/kg/d for 7 d) were investigated using UPLC-MS/MS. The main pharmacokinetic parameters were calculated and compared. The MS analysis was performed in positive ionization mode. The purpose of chromatographic separation of AZ and the internal standard (IS, Valsartan) was finished on a Waters XBridge BEH C18 column (2.1 × 100 mm, 2.5 µm). The mobile phase was acetonitrile and 0.1 % formic acid-water with gradient elution at a flow rate of 0.4 mL/min. The mRNA and protein levels of CYP2B1, CYP2C6, and CYP2C11 in the rat liver were detected by qRT-PCR and western blot, respectively. The results indicated that low, medium and high doses of CDDP significantly increased the Cmax (6.47 ± 2.28, 6.51 ± 1.99, 7.04 ± 1.31 vs. 3.30 ± 1.87) of AZ, compared with that in the AZ single-drug group (p<0.05). The AUC0-t of AZ (47.77 ± 23.41, 50.69 ± 25.46, 54.50 ± 11.57 vs. 26.85 ± 16.79) tended to increase in combination with CDDP. The gene and protein expression levels of CYP2B1, CYP2C6, and CYP2C11 were significantly reduced in the rat liver by CDDP. CDDP may diminish the AZ metabolism in vivo by suppressing the expression of the CYP2B1, CYP2C6, and CYP2C11 enzymes. This observation suggested the occurrence of potential interactions between CDDP and AZ when clinically administered as combination therapy, which may require adjustment of the clinical dose of AZ.

Comparative pharmacokinetics of seven bioactive components in normal, sham-operated, and myocardial ischemia-reperfusion injury rats after oral administration of the Salvia Miltiorrhiza-Moutan Cortex herb pair.

Recently the Salvia Miltiorrhiza-Moutan Cortex (SM-MC) herb pair is considered as a promising Chinese medicinal mixture exhibiting a range of pharmacological activities, including treating cardiovascular disease due to its unique composition. In this study, we conducted the comparative pharmacokinetic analysis of seven main bioactive components of SM-MC in a different model rat. A straightforward ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) strategy that could simultaneously evaluate the levels of seven compounds was used to ensure the reliability of these pharmacokinetic analyses in rat plasma. The rat plasma samples were collected from normal, sham-operated, and myocardial ischemia-reperfusion injury (MIRI) groups at predetermined time points after the administration of SM-MC. The main pharmacokinetic parameters were detected and calculated. We successfully assessed the maximum concentration (Cmax ), time to Cmax (Tmax ), the elimination rate constant (λz ), total half-life (t1/2 ), total body clearance (CL), and the area under the concentration-time curve from 0 to last sampling time (AUC0-t ) and extrapolated to infinity (AUC0-∞ ). To sum up, an optimized UPLC-MS/MS approach that could be used to rapidly, simultaneously, and sensitively detect seven bioactive compounds derived from SM-MC extract preparations was successfully developed, which may offer a pharmacokinetic basis for preclinical and clinical studies of SM-MC herb pair for treating MIRI.