Mingzhen He

Ionic liquid-based ultrasound-assisted extraction and aqueous two-phase system for analysis of caffeoylquinic acids from Flos Lonicerae Japonicae

In this work, an ionic liquid-based ultrasonic-assisted extraction (ILUAE) method was developed to extract caffeoylquinic acids (CQAs) from Flos Lonicerae Japonicae (FLJ). ILUAE parameters were optimized by response surface methodology, including IL concentration, ultrasonic time, and liquid-solid ratio. Optimized ILUAE approach gained the highest extraction yields of 28.53, 18.21, 3.84mg/g for 3-O-caffeoylquinic acid (C1), 3,5-di-O-caffeoylquinic acid (C2), 3,4-di-O-caffeoylquinic acid (C3), respectively. C1-C3 are the three most abundant CQAs compounds in FLJ. The method showed comparable extraction yield and shorter extraction time compared with conventional extraction techniques. Subsequently, an aqueous two-phase system (ATPS) was applied in extraction solutions. Two trace CQAs, 5-O-caffeoylquinic acid (C4) and 4,5-di-O-caffeoylquinic acid (C5), were significantly enriched with signal to noise values increasing from less than 10 to higher than 1475. The results indicated that ILUAE and ATPS are efficient and environmentally-friendly sample extraction and enrichment techniques for CQAs from herbal medicines.

Metabolites profiling of Pulsatilla saponin D in rat by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS/MS).

Pulsatilla saponin D, an antitumor substance isolated from traditional Chinese herbal medicine Pulsatilla chinensis (Bge.) Regel, is a promising candidate for new drug development. The purpose of the present study is to establish a simple and practical strategy for the metabolite profiling of Pulsatilla saponin D in vivo. A total of 18 metabolites were identified in rat plasma, urine and feces samples based on MS and MS/MS data by using ESI-Q-TOF-MS/MS, and eight of them (M11-M18) were reported for the first time. The results indicated that deglycosylation, dehydrogenation, hydroxylation and sulfation were the major metabolic transformations of Pulsatilla saponin D in vivo. This study has improved our understanding of the metabolic fate of Pulsatilla saponin D in vivo, and the information gained from the current study is relevant to the pharmacological activity of Pulsatilla saponin D.

Nitric oxide-donating derivatives of hederacolchiside A1: Synthesis and biological evaluation in vitro and in vivo as potential anticancer agents.

A series of nitric oxide (NO) donating derivatives of hederacolchiside A1 bearing triterpenoid saponin motif were designed, synthesized and evaluated for their anticancer activity. All of the tested furoxan-based NO releasing compounds showed significant proliferation inhibitory activities. Especially compound 6a exhibited strong cytotoxicity (IC50=1.6-6.5μM) against four human tumor cell lines (SMMC-7721, NCI-H460, U251, HCT-116) in vitro and the highest level of NO releasing. Furthermore, compound 6a was revealed low acute toxicity to mice and weak haemolytic activity with potent tumor growth inhibition against mice H22 hepatocellular cells in vivo (51.5%).

A robust platform based on ultra-high performance liquid chromatography Quadrupole time of flight tandem mass spectrometry with a two-step data mining strategy in the investigation, classification, and identification of chlorogenic acids in Ainsliaea fragrans Champ

The chlorogenic acids are the major bioactive constituents of the whole plant of Ainsliaea fragrans Champ. (Xingxiang Tuerfeng). These compounds are usually present as isomeric forms in Xingxiang Tuerfeng. Therefore, an efficient approach should be developed for the rapid discovery and identification of chlorogenic acids isomers through the fragmentation pathway and rules. In this study, the collision induced dissociation tandem mass spectrometry (CID-MS/MS) fragmentation routes of chlorogenic acids were systematically investigated by UHPLC-QTOF-MS/MS in the negative ion mode using eight chlorogenic acids standards. As a result, diagnostic product ions for rapid discovery and classification of chlorogenic acids isomers were determined according to their MS/MS fragmentation patterns and intensity analysis. Based on these findings, a novel two-step data mining strategy was established. The first key step was to screen different kinds of substitution and the skeleton of the quinic acid using the characteristic product ions and neutral losses. The second key step was to screen and classify different types of chlorogenic acids using their diagnostic product ions. It was apply to the rapid investigation, classification, and identification of chlorogenic acids. And the same carbon skeletons from a complex extract of Ainsliaea fragrans Champ. were effectively identified. 88 constituents, including 14 chlorogenic acids types, were rapidly discovered and identified, and in particular, 12 types of chlorogenic acids, including p-CoQC, FQA, BQC, CQA-Glu, CFQA, p-Co-CQC, di-p-CoQC, BCQA, di-CQA-Glu, PCQA, tri-QCA, and P-di-CQA, were first discovered in Ainsliaea fragrans Champ. In conclusion, UHPLC-QTOF-MS/MS method together with a systematic two-step data mining strategy was established as a feasible, effective, and rational technique for analyzing chlorogenic acids. Additionally, this study laid a foundation for the study of the active substances and quality control of Ainsliaea fragrans Champ.

A rapid and sensitive LC-MS/MS method for the determination of Pulsatilla saponin D in rat plasma and its application in a rat pharmacokinetic and bioavailability study

A simple, sensitive and specific liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of Pulsatilla saponin D, a potential antitumor constituent isolated from Pulsatilla chinensis in rat plasma. Rat plasma samples were pretreated by protein precipitation with methanol. The method validation was performed in accordance with US Food and Drug Administration guidelines and the results met the acceptance criteria. The method was successfully applied to assess the pharmacokinetics and oral bioavailability of Pulsatilla saponin D in rats.

Application of a liquid chromatography-tandem mass spectrometry method to the pharmacokinetics, tissue distribution and excretion in the study of anemoside B4, a novel antiviral agent candidate, in rats

A simple, sensitive and reliable LC-MS/MS method was developed and validated for the quantification of anemoside B4, a potential antiviral constituent isolated from Pulsatilla chinensis in rat plasma, tissue, bile, urine and feces. All biological samples were prepared by protein precipitation method, and ginsenoside-Rg1 was chosen as the internal standard (IS). The analyte and IS were separated using a C18 column (2.1 × 50 mm, 1.8 μm) and a mobile phase consisting of 0.1% formic acid in water (v/v) and acetonitrile running at a flow rate of 0.2 mL/min for 5 min. The multiple reaction monitoring transitions were monitored at m/z 1219.5-749.5 for anemoside B4 and 845.4-637.4 for ginsenoside-Rg1 in electrospray ionization negative mode. The calibration curve was linear in the range of 10-2000 ng/mL for all biological matrices with a lower limit of quantification of 10 ng/mL. The validated method was successfully applied to a pharmacokinetics, tissue distribution and excretion study. These preclinical data will be beneficial for further development of anemoside B4 in future studies.

Ion mobility mass spectrometry with molecular modelling to reveal bioactive isomer conformations and underlying relationship with isomerization

RATIONALE In medicine and drug development, molecular modelling is an important tool. It is attractive to develop a platform connecting the theoretical structural modelling and the results from experimental measurement. In addition, the separation and structural analysis of bioactive constituent isomers are still challenging tasks. METHODS Drift tube ion mobility (IM) mass spectrometry (MS) provides the experimental collision cross section (CCS) which contains the structural information. The experimental CCS can be compared with the calculated CCS of the molecular modelling structures. This technique is especially useful for bioactive constituents in herbal medicine because active isomers with the same chemical formula are common in these samples. IM helps separate and identify these isomers and reveals details about their structures and conformations. RESULTS Two model bioactive constituents, caffeoylquinic acids (CQAs) and dicaffeoylquinic acids (di-CQAs), were selected to systematically investigate the influence of solution, ion source conditions and ion heating on the isomer CCS distributions. By comparing the calculated CCS with the experimental value, we identified the favorable conformations of CQAs. The most compact conformation of a CQA was less likely to isomerize than the more extended conformation. It was found that the isomerization tendency was in accord with the conformation favorability. CONCLUSIONS This study offers an effective approach to predict and demystify the conformation and isomerization of the active constituents in herbal medicines.

An integrative investigation of the therapeutic mechanism of Ainsliaea fragrans Champ. in cervicitis using liquid chromatography tandem mass spectrometry based on a rat plasma metabolomics strategy

HighlightsThirty‐two potential biomarkers were identified in the response to rat cervicitis.Twenty‐seven potential biomarkers exhibited altered levels in the AFC group compared to the model group.Ainsliaea fragrans Champ. showed therapeutic effect of rat cervicitis induced by hydroxybenzene mucilage. ABSTRACT Cervicitis is an extremely common gynecological disease and can be induced by diverse factors such as Neisseria gonorrhoeae, Chlamydia trachomatis, and Mycoplasma genitalium infections. Long‐term unhealed cervicitis may lead to a series of diseases including endometritis, salpingitis, pelvic inflammatory disease, and chorioamnionitis. However, the pathogenesis of cervicitis remains unknown. Ainsliaea fragrans Champ. (AFC) has been widely used in clinical treatment of cervicitis. In the present study, we performed an integrative investigation involving histopathology analysis and non‐target plasma metabolomics analysis in a cervicitis rat model induced by phenol mucilage, using ultra‐performance liquid chromatography coupled with a tandem quadrupole time‐of‐flight mass spectrometry approach. Based on the integrative investigation, marked metabolomic differences were identified between the cervicitis and control groups using multivariate analysis. As a result, 32 potential biomarkers were identified in the response to cervicitis, and were involved in arachidonic acid metabolism, linoleic acid metabolism, primary bile acid biosynthesis, taurine and hypotaurine metabolism, pantothenate and CoA biosynthesis, and glycerophospholipid metabolism. After treatment, a total of 27 potential biomarkers exhibited altered levels in the AFC group compared to the model group, and 12 metabolites including 1‐stearoylglycerophosphoinositol, bolasterone, lysoPC(16:0), lysoPC(20:4), lysoPC(P‐16:0), lysoPC(P‐18:0), lysoPC(P‐18:1), stearoylcarnitine, taurine, lysoPC(17:0), 20‐hydroxyeicosatetraenoic acid, and 1‐arachidonoylglycerophosphoinositol returned to their normal levels. This study suggested that the therapeutic mechanism of AFC is related to those altered endogenous metabolites.

Application of characteristic ion filtering with ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry for rapid detection and identification of chemical profiling in Eucommia ulmoides Oliv

Efficient targeted identification of chemical constituents from traditional Chinese medicine is still a major challenge. In this study, we used a characteristic ion filtering strategy to characterize compounds of Eucommia ulmoides Oliv. by ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UHPLC-ESI-Q-TOF-MS/MS). By using the ion filtering approach, target constituents of Eucommia ulmoides Oliv. were easily tentatively identified from the enormous LC/MS data set. The strategy consisted of the following three steps: 1) To establishing a characteristic ion database by diagnostic product ions or neutral loss fragments; 2) To evaluate the structural information of the compounds by high-resolution diagnostic characteristic ion filtering; 3) To confirm the different classes by chemical profiling according to their MS/MS spectra. In this study, characteristic ions are summarized as five major groups of compounds in Eucommia ulmoides Oliv. In total, 113 compounds were tentatively identified, including 23 potentially novel compounds. The results form a foundation for the quality control and chemical basis of Eucommia ulmoides Oliv.

Comparative Metabolomics Analysis of Cervicitis in Human Patients and a Phenol Mucilage-Induced Rat Model Using Liquid Chromatography Tandem Mass Spectrometry

Cervicitis is an exceedingly common gynecological disorder that puts women at high risk of sexually transmitted infections and induces a series of reproductive system diseases. This condition also has a significant impact on quality of life and is commonly misdiagnosed in clinical practice due to its complicated pathogenesis. In the present study, we performed non-targeted plasma metabolomics analysis of cervicitis in both plasma samples obtained from human patients and plasma samples from a phenol mucilage induced rat model of cervicitis, using ultra-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry. In addition to differences in histopathology, we identified differences in the metabolic profile between the cervicitis and control groups using unsupervised principal component analysis and orthogonal projections to latent structures discriminant analysis. These results demonstrated changes in plasma metabolites, with 27 and 22 potential endogenous markers identified in rat and human samples, respectively. The metabolic pathway analysis showed that linoleic acid, arachidonic acid, ether lipid, and glycerophospholipid metabolism are key metabolic pathways involved in cervicitis. This study showed the rat model was successfully created and applied to understand the pathogenesis of cervicitis.