Dynamic metabolic profile of Zhi-Zi-Da-Huang decoction in rat urine based on hybrid liquid chromatography–mass spectrometry coupled with solid phase extraction

An ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry method based on a four-step analysis strategy to investigate metabolites of Qi-Yu-San-Long decoction in rat plasma

Metabolism is undoubtedly significantly correlated with the efficacy and safety of traditional Chinese medicine. In clinic, Qi-Yu-San-Long decoction (QYSLD) has achieved good results in the treatment of non-small-cell lung cancer (NSCLC). Nevertheless, a detailed understanding of the compounds (prototypes and metabolites) of QYSLD and its dynamic metabolic profile in plasma has not been revealed.

METHODS

In this study, a rapid and sensitive method based on ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF/MS^E ), combined with a four-step analysis strategy, was established to investigate QYSLD metabolic profile in rat plasma.

RESULTS

In all, 101 xenobiotics (41 prototypes and 60 QYSLD-related metabolites) were identified in rat plasma. The research uncovered metabolic profiles of alkaloids, saponins, flavonoids, iridoids, anthraquinones, and phenylpropanoids of QYSLD in rat plasma. The dynamic changes in these xenobiotics were also observed at different time intervals. At 0.5 h after oral administration, only 15 prototypes and 11 metabolites were detected. Within 24 h, 4 prototypes and 20 metabolites can still be detected. Four prototypes and 10 metabolites had the phenomenon of emergence-disappearance-reappearance in vivo.

CONCLUSION

In rat plasma, 101 xenobiotics of QYSLD were identified and their dynamic metabolic profiles were systematically delineated, which laid a material basis for further research of the pharmacodynamic substances of QYSLD inhibiting NSCLC.

A Rapid High Throughput Vibration and Vortex-Assisted Matrix Solid Phase Dispersion for Simultaneous Extraction of Four Isoflavones for Quality Evaluation of Semen Sojae Praeparatum

Isoflavones (daidzein, daidzin, genistein and genistin) were main chemical components and usually selected as markers for quality control of Traditional Chinese Medicine semen sojae praeparatum (SSP). High throughput vibration and vortex-assisted matrix solid phase dispersion and high performance liquid chromatography with diode array detection were developed to simultaneously extract and quantify four isoflavones in SSP. Some parameters influencing extraction efficiency of isoflavones by vortex-assisted matrix solid phase dispersion such as sorbent type, ratio of sample to sorbent, crushing time, vibration frequency, methanol concentration, eluting solvent volume and vortex time were optimized. It was found that the best extraction yields of four isoflavones were obtained when the sample (20 mg) and SBA-3 (40 mg) was crushed by ball mill machine for 2 min at vibration frequency of 800 times per minute. Methanol/water (1.5 ml, 8:2, v/v) solution was dropped into the treated sample and vortexed for 3 min. The recoveries of the four isoflavones ranged from 86.1 to 94.8% and all relative standard deviations were less than 5%. A good linearity (r > 0.9994) was achieved within the range 0.5-125 μg/ml. It was concluded that the high throughput vibration and vortex-assisted matrix solid-phase dispersion coupled with high performance liquid chromatography was user-friendly extraction and quantification method of multiple isoflavones for quality evaluation of SSP.

Multi-Component Comparative Pharmacokinetics in Rats After Oral Administration of Fructus aurantii Extract, Naringin, Neohesperidin, and Naringin-Neohesperidin

Citrus × aurantium L., Chinese name: Fructus Aurantii (FA) has been largely used as Qi-invigorating herb in China for centuries. The main components (meranzin hydrate, naringin, neohesperidin, meranzin, nobiletin) have good physiological activity with relatively high abundance in FA. Few multi-component comparative pharmacokinetics are simultaneously accessible for the flavone glycosides, polymethoxy flavones, and coumarins in FA. In this work, a reliable and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established and validated to determine the five ingredients in the SD rat plasma, and further applied to the pharmacokinetic studies after oral administration of monomer, drugs in compatibility, and FA extract. After hydrolysis with β-glucuronidase and sulfatase, the concentration of naringin and neohesperidin in rat plasma were expressed respectively by the total concentration of naringenin and hesperitin which was determined by UPLC-MS/MS. Double-peak phenomenon was observed for naringin and neohesperidin, which may be due to the enterohepatic circulation or multiple site absorption of the two flavone glycosides. Meranzin hydrate and meranzin (coumarins) were absorbed rapidly (T_max, about 1.0 h) but eliminated slowly (t_1/2z exceeds 6.5 h). Nobiletin, a typical polymethoxy flavone, was also rapidly absorbed according to T_max and AUC_(0-t). DAS 3.1 software suggests the pharmacokinetic profiles of the five components in rats be depicted as a two-compartment pharmacokinetic model. There were significant differences in pharmacokinetic parameters for naringenin and hesperetin between the compatibility, FA extract group vs monomer group: ① remarkable increases in the values of AUC_(0–∞), AUC_(0–t) and C_max; ② obvious decrease of CL_Z/F; and ③ longer t_max and t_1/2z. The results suggest that compatibility can promote mutual absorption and affect the elimination behaviors.

Isoflavones' effects on pharmacokinetic profiles of main iridoids from Gardeniae Fructus in rats

Gardeniae Fructus (GF) and Semen Sojae Praeparatum (SSP) are both medicine food homologies and widely used in Chinese clinical prescriptions together. The research investigated the pharmacokinetics of four iridoids in normal rats and isolfavones-fed rats, which were administered with isolfavones from SSP for 7, 14, 21 and 28 consecutive days. A validated LC-MS/MS method was developed for determining shanzhiside, genipin-1-gentiobioside, geniposide and their metabolite genipin in rat plasma. Plasma samples were pretreated by solid-phase extraction using paeoniflorin as the internal standard. The chromatographic separation was performed on a Waters Atlantis T3 (4.6 mm × 150 mm, 3 μm) column using a gradient mobile phase consisting of acetonitril and water (containing 0.06% acetic acid). The mass detection was under the multiple reaction monitoring (MRM) mode via polarity switching between negative and positive ionization modes. The calibration curves exhibited good linearity (r > 0.997) for all components. The lower limit of quantitation was in the range of 1–10 ng/mL. The intra-day and inter-day precisions (RSD) at three different levels were both less than 12.2% and the accuracies (RE) ranged from −10.1% to 16.4%. The extraction recovery of them ranged from 53.8% to 99.7%. Pharmacokinetic results indicated the bioavailability of three iridoid glycosides and the metabolite, genipin in normal rats was higher than that in rats exposed to isoflavones. With the longer time of administration of isoflavones, plasma concentrations of iridoids decreased, while genipin sulfate, the phase Ⅱ metabolite of genposide and genipin-1-gentiobioside, appeared the rising exposure. The pharmacokinetic profiles of main iridoids from GF were altered by isoflavones.

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A LC-MS/MS method for determination of four iridoids in rat plasma was developed and applied.

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The bioavailability of four iridoids decreased in rats with their increasing isoflavones exposure time.

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Isoflavones could alter the fate of iridoids in vivo when GF and SSP were prescribed together to obtain toxicity-reducing.

A target-group-change couple with mass defect filtering strategy to identify the metabolites of "Dogel ebs" in rats plasma, urine and bile

"Dogel ebs" was known as Sophora flavescens Ait., a classical traditional Chinese Mongolian herbal medicine, which had the effects on damp-heat dysentery, scrofula, and syndrome of accumulated dampness toxicity. Although the chemical constituents have been clarified by our previous studies, the metabolic transformation of "Dogel ebs" in vivo was still unclear. To explore the mechanism of "Dogel ebs," the metabolites in plasma, bile, and urine samples were investigated. A fast positive and negative ion switching technology was used for the simultaneous determination of flavonoids and alkaloids in "Dogel ebs" in a single run. And a target-group-change coupled with mass defect filtering strategy was utilized to analyze the collected data. 89 parent compounds and 82 metabolites were characterized by high-performance liquid chromatography with quadrupole exactive Orbitrap mass spectrometry. Both phase I and phase II metabolites were observed and the metabolic pathways involved in oxidation, demethylation, acetylation, and glucuronidation. 69 metabolites of "Dogel ebs," including three hydroxyls bonding xanthohumol, formononetin-7-O-glucuronide, 2'-hydroxyl-isoxanthohumol decarboxylation metabolite, oxysophocarpine dehydrogen, 9α-hydroxysophoramine-O-glucuronide, etc. were reported for the first time.

Investigation of metabolic profile of pimavanserin in rats by ultrahigh-performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry

RATIONALE

Pimavanserin, a selective serotonin 2A receptor inverse agonist, is a promising candidate for treating Parkinson's disease psychosis. Our previous study revealed that there might be the presence of extensive metabolites of pimavanserin in rats. However, the metabolic fate of pimavanserin in vivo remains unknown. Thus, it is essential to develop an efficient method to investigate the metabolic profile of pimavanserin in rats. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to date has the highest mass measurement accuracy and resolution of any mass spectrometry platform.

METHODS

After a single intragastric administration of pimavanserin at a dose of 50 mg kg^-1 , plasma, bile, urine and feces were collected from rats. A novel and efficient strategy was developed to analyze the metabolic profile of pimavanserin in vivo based on ultrahigh-performance liquid chromatography (UHPLC) coupled with FT-ICR-MS.

RESULTS

A total of 23 metabolites were detected and tentatively identified through comparing their mass spectrometry profiles with those of pimavanserin. These metabolites were found in feces (22), bile (21), rat urine (16) and plasma (15). Results demonstrated that metabolic pathways of pimavanserin in rats included dehydrogenation, demethylation, deethylation, depropylation, debutylation, hydroxylation, dihydroxylation and trihydroxylation.

CONCLUSIONS

A total of 22 phase I metabolites of pimavanserin were detected and tentatively identified. This report presents the first study of screening and identification of the metabolites of pimavanserin. The UHPLC/FT-ICR-MS method is a powerful tool for exploring and identifying metabolites in complex biological samples.