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Since most anti-glioma drug candidates hardly permeate through the blood-brain barrier (BBB), preclinical models that can integrate the complexity of the tumor microenvironment and the structure and function of the BBB is urgently needed for the treatment of glioma. Herein, we constructed an in vitro BBB-glioma microfluidic chip model lined by primary human brain microvascular endothelial cells, pericytes, astrocytes and glioma cells, which could recapitulate the high level of barrier function of the in vivo human BBB and glioma microenvironment. The BBB unit in BBB-glioma microfluidic chip (BBB-U251 chip) displayed selective permeability to fluorescein isothiocyanate isomer-dextran (FITC-dextran) with different molecular weights and three model drugs with different permeability behavior across BBB, which indicated that this glioma model included a functional barrier. Six potential anti-glioma components in traditional Chinese medicine (TCM) were delivered into the blood channel and the permeated amount was quantified by high-performance liquid chromatography combined with ultraviolet (HPLC-UV). The permeated drugs then directly acted on 3D cultured glioma cells (U251) to evaluate the drug efficacy. The results of permeability coefficients of drugs showed that the data were closer to the in vivo data of traditional Transwell model. The effect of the drugs on U251 cells in the BBB-U251 chip was significantly lower due to the existence of BBB. Drug responses on glioma demonstrated the necessity to take BBB into account during the development of anti-glioma new drugs. Therefore, this 3D glioma microfluidic models integrating the BBB functionality can be a useful platform for screening the anticancer drug for brain tumors.

Cell membrane chromatography (CMC) has been widely used for characterizing the interaction between drugs and membrane receptors to screen target components from herbal medicines. However, the column life, stability, and the efficiency cannot meet the needs of high-throughput screening purpose. In this study, a P-glycoprotein immobilized cell membrane stationary phase (P-gp/CMSP) was prepared with a simple and mild two-step aldehyde modification, realizing the covalent bonding between cell membrane and stationary phase. The column life and stability were significantly enhanced compared with the unmodified columns. The P-gp/CMC column was equipped into a comprehensive 2D P-gp/CMC/Capcell-C18/TOFMS system, which actualizes the automated and high-throughput analytical process and rapid identification of complex chemical samples with no data loss. Five compounds with significant retention were screened out and unambiguously identified by the comprehensive 2D analytical system. Baicalin was confirmed as a P-gp inhibitor with ATP depletion inhibition ratio of 83.4%. Moreover, the reversal index of baicalin on DOX significantly increased to 11.13 when its concentration reached 25 μM, revealing that baicalin could effectively reverse the MDR cell model induced by DOX. The integrated system is a practical drug discovery platform and could be applied to other transmembrane protein models.

Cancer metastasis is one of the most serious problems for tumor therapy, which is closely related to cell adhesion and deadhesion process. Better comprehension of cell adhesion ability will benefit drug research. Here, a biomimetic microfluidic enzyme digestion method was proposed to gently measure the influence of drugs on cell-matrix adhesion ability at the single cell level. The method can selectively digest the extracellular matrix (ECM) that linked to a single cell, and the trypsin concentration around the cell is relatively uniform and constant, thus the measured cell adhesion strength should be precise. Commercially available anti-cancer agents including 5-fluorouracil (5-FU), actinomycin D (Act D), temozolomide (TMZ) and allicin were evaluated, and the data showed only TMZ and allicin can inhibit cell adhesion significantly under our experiment conditions. The influence of TMZ became more and more obvious as the increase of duration and the effect became prominent only after 6 h adhesion process, which could provide a quick evaluation of whether the drugs are effective to cancer cell (compared with Calcein-AM/PI cell viability test). The adhesion strength of U87 cells decreased when the concentration of TMZ increased, and the effect of TMZ can be effectively inhibited by adding lactic acid to culture medium, which indicated acidic tumor microenvironment could promote drug resistance of tumor cells. Different from conventional evaluation methods which focus on the drugs’ influence on cellular viability or metabolism, this work provides a new perspective to study the effect of drugs, which is helpful to enrich the drug evaluation system.

Screening of bioactive ligands for a certain protein target from medicinal herbs is a highly important yet challenging task during drug discovery process. In this study, a surface plasmon resonance biosensor-based active ingredient recognition system (SPR-AIRS) was applied to screen p38 mitogen-activated protein kinase (p38) ligands from herbal extracts. After p38 protein was immobilized on a SPR chip and the suitability of SPR-AIRS was validated, thirty-four p38-related medicinal herbs were selected and pre-screened. Two medicinal herbs having high response signal with p38-immobilized chip, Folium Ginkgo and Herba Artemisiae Scopariae, were injected into SPR system for ligand fishing. Among them, two active compounds, eupatilin (EPT) and ginkgolide B (GKB), were identified as p38 ligands, and then the KD values of EPT and GKB were measured as 21.68 ± 2.21 and 44.71 ± 1.80 μM, respectively. They can inhibit p38 activities significantly and bind to the ATP binding site on p38. Furthermore, EPT and GKB can inhibit cell proliferation (IC50 = 30.31 ± 6.84 and 42.97 ± 0.83 μM), induce apoptosis and G2/M cell cycle arrest against K562 cell line. This is the first time that EPT and GKB are reported as effective p38 binding ligands. These results prove that SPR-AIRS could be an effective method to screen active compounds acting on a specific protein from complex systems.

Microorganisms are not only common pathogens in clinical practice, but also an important participant in the maintenance of ecological balance, which plays a vital role in food production, microbial industry, and biomedical research etc. The traditional methods for bacterial and fungi research are time-consuming, high-cost, accurate operation required and unable to realize single-cell analysis. Microfluidic technologies have been applied to microorganism studies recently. Microfluidic devices with micro-sized scale and large-scale integration offer many special benefits including low cost, high throughput, and high efficiency in microorganism analysis. In this paper, we review the development and applications of microfluidic devices with respect to bacteria and fungus, and emphasize the advantages over traditional methods. Most crucially, we discuss how microfluidic chip technology contributes to the study of bacteria, fungus and their interactions. Finally, we provide insights into the challenges of bacterial and fungi studies based on microfluidic chip and present future perspectives.

Dispersive liquid-liquid microextraction (DLLME) is a mini-extraction technology with merits of low cost, environment friendliness, and high extraction efficiency; moreover, this method is easy to operate and requires only a short operation time. In this paper, several extraction models, including normal dispersive liquid-liquid microextraction, ionic liquid dispersive liquid-liquid microextraction, and ultrasound-assisted dispersive liquid-liquid microextraction, are reviewed according to the type of extraction solvents and dispersive methods. This paper also summarizes the application of DLLME to the analysis of biological samples in the last five years.

A novel surface plasmon resonance–based P-gp ligand screening system (SPR-PLSS) combined with lentiviral particle (LVP) stabilization strategy was constructed to screen out potential P-gp inhibitors from natural products. Firstly, we constructed LVPs with high and low expression levels of P-gp. The LVPs can ensure the natural conformation of P-gp based on the principle that LVPs germinated from packaging cells will contain cell membrane fragments and P-gp they carry. Then the LVPs with high P-gp expression for active channel and LVPs with low P-gp expression for reference channel were immobilized on CM5 chip respectively. The affinity detection was thus carried out with the signal reduction on the two channels. The P-gp inhibitors, Valspodar (Val) and cyclosporin (CsA), as positive compounds, were detected to characterize the chip’s activity, and the KD of Val and CsA were 14.09 μM and 16.41 μM, respectively. Forty compounds from natural product library were screened using the SPR CM5 chip, and magnolol (Mag), honokiol (Hon), and resveratrol (Res) were screened out as potential P-gp ligands, showing a significant response signal. This work presented a novel P-gp ligand screening system based on LVP-immobilized biosensor to rapidly screen out P-gp ligands from natural product library. Compared with traditional cell experiments which the screening time may take up to several days, our method only takes several hours. Furthermore, this study has also provided solid evidences to support that some complicated membrane proteins would apply to the lentivirus-based SPR screening system.

Background: Pantoprazole and atorvastatin are often used jointly in the clinic. The drug-drug interaction of pantoprazole and atorvastatin is worthy of being investigated. Objective: A highly rapid, sensitive, and selective LC-MS/MS method was developed for simultaneous quantification of pantoprazole and atorvastatin in rat plasma. Methods: Omeprazole and atorvastatin-d5 were used as the internal standards (ISs) of pantoprazole and atorvastatin, respectively. Simple protein precipitation was used to extract analytes from 50.0 μL plasma samples. Results: The chromatographic separation was achieved on a C18 column and the total chromatographic run time was 3.2 min. Acquisition of mass spectrometric data was performed on a triple-quadrupole mass spectrometer in multiple- reaction-monitoring (MRM) mode with an ESI source using the transition m/z 384→ 200 for pantoprazole and m/z 559.4→ 440.2 for atorvastatin, respectively. The method was validated over the concentration range of 20.0 ∼ 5000 ng/mL for pantoprazole and 1.00 ∼ 250 ng/mL for atorvastatin. All the validation results, including linearity, specificity, precision, accuracy, extraction recovery, matrix effect, and stability, met the acceptance criteria as per FDA guidelines. Conclusion: This method was successfully applied to a pharmacokinetic interaction study in Wistar rats. The results revealed significant evidence for the drug-drug interaction between pantoprazole and atorvastatin.

Crystal-induced kidney injury (CIKI) is the fundamental pathological change during nephrolithiasis, although the molecular mechanism is still unclear. Pyrrosia calvata (Bak.) Ching has been used in folk medicine to treat urolithiasis for years. To clarify the pharmacodynamic substances and the mechanism of its antiurolithiasis effects, in this study, a novel, stop-flow, comprehensive, two-dimensional (2D) HK-2 and HK-2/CIKI cell membrane chromatography (CMC) comparative analysis system was developed to screen for the potential active ingredients from Pyrrosia calvata (Bak.) Ching against CIKI. The comprehensive 2D CMC comparative analysis system showed satisfactory selectivity, and eight ingredients were screened and identified by this system. Among them, mangiferin exhibited higher affinity for the HK-2/CIKI CMC column than the HK-2 CMC column and was selected for further efficacy verification. Cell proliferation assays showed that mangiferin could protect HK-2 cell viability after stimulation with sodium oxalate (NaOX). Additionally, in a rodent model of CIKI, mangiferin decreased the deposition of calcium oxalate (CaOX) crystals in mouse kidneys, alleviated the pathological damage to kidney tissue, and inhibited the upregulation of OPN, MCP1, and CD44 expression caused by CaOX crystals. The established comprehensive 2D CMC comparative analysis system can be applied to screen active ingredients with disease specificity from traditional Chinese medicine (TCM) and is suitable for other cell models.

Combinations of new antidepressants like duloxetine and second-generation antipsychotics like quetiapine are used in clinical treatment of major depressive disorder, as well as in forensic toxicology scenarios. The drug–drug interaction (DDI) between quetiapine and duloxetine is worthy of attention to avoid unnecessary adverse effects. However, no pharmacokinetic DDI studies of quetiapine and duloxetine have been reported. In the present study, a rapid and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of quetiapine and duloxetine in rat plasma. A one-step protein precipitation with acetonitrile was applied for sample preparation. The analytes were eluted on an Eclipse XDB-C18 column using the mixture of acetonitrile and 2 mM ammonium formate containing 0.1% formic acid at a gradient elution within 6.0 min. Quantification was performed in multiple-reaction-monitoring mode with the ion transitions m/z 384.4 → 253.2 for quetiapine, m/z 298.1 → 154.1 for duloxetine and m/z 376.2 → 165.2 for IS (haloperidol), respectively. Good linearity was obtained in the range of 0.50–100 ng/mL for quetiapine (r2 = 0.9972) and 1.00–200 ng/mL for duloxetine (r2 = 0.9982) using 50 μL of rat plasma, respectively. The method was fully validated with accuracy, precision, matrix effects, recovery and stability. The validated data have met the acceptance criteria in FDA guideline. The method was applied to a pharmacokinetic interaction study and the results indicated that quetiapine had significant effect on the enhanced plasma exposure of duloxetine in rats under combination use. This study could be readily applied in therapeutic drug monitoring of major depressive disorder patients receiving such drug combinations. Keywords: LC-MS/MS, Quetiapine, Duloxetine, Pharmacokinetics, Drug–drug interaction

Cell membrane chromatography, which has been used to build an in vitro screening model, has become a practical method to screen active ingredients of traditional Chinese medicine (TCM) or study the interaction between drugs and receptors. In this paper, the development of cell membrane chromatography and its preparation methods, the optimization of the system and methodological for stability and other issues were reviewed, as well the unique advantages on the selection of active ingredients of TCM. On this basis, the future development trend of cell membrane chromatography technique was discussed to provide ideas for the further development of cell membrane chromatography and its further application in the field of drug high throughput screening

A surface plasmon resonance (SPR) biosensor-based active ingredients recognition system (SPR-AIRS) was developed, validated, and applied to screen signal transducer and activator of transcription 3 (STAT3) ligands. First, features of the screening system were investigated in four aspects: (1) specificity of the STAT3-immobilized chip, it shows that the chip could be applied to screen STAT3 ligands from complex mixture; (2) linearity and limit of detection (LOD) of the system, the minimum recovery cycle number was determined as 5 cycles; (3) saturability of the chip, the results indicate that it is necessary to select a proper concentration based on the compound's Kd value; (4) robustness of the system, it indicates that inactive compounds in the matrix could not interfere with active compounds in the process of screening. Next, SPR-AIRS was applied to screen STAT3 ligands from medicinal herbs. Nine candidate compounds were fished out. Then SPR assay and molecular docking were performed to verify the interplay between STAT3 and candidate compounds. Apoptosis assay and luciferase report assay were performed to investigate the drug effect of candidate compounds on STAT3 activity. Western blot results indicated that neobaicalein and polydatin could inhibit the phosphorylation of STAT3. As far as we know, this is the first time that neobaicalein and polydatin are reported as effective STAT3 ligands. In a conclusion, we have systemically demonstrated the feasibility of SPR biosensor-based screening method applying to complex drug systems, and our findings suggest that SPR-AIRS could be a sensitive and effective solution for the discovery of active compounds from a complex matrix.

Studies have documented the potential antitumor activities of glaucocalyxin A (GLA), an ent-kaurene diterpenoid isolated from Rabdosia japonica. However, the metabolic mechanism underlying the antitumor activity of GLA remains largely unknown. The effects of GLA on the metabolome of human liver cancer cells using GC/MS- and LC/MS-based metabolic profiling have been investigated. An untargeted metabolomics approach in conjunction with orthogonal projection to latent structures-discriminant analysis (OPLS-DA) has been developed to characterize the metabolic modifications induced by GLA treatment in human hepatoma cell line SMMC7721. Results demonstrated that cells cultured in the presence or absence of GLA displayed different metabolic profiles: the treatment induced an increased purine metabolism, pyrimidine metabolism, and sphingolipid metabolism and a decreased amino acid metabolism. At the same time, GLA treatment induced cell apoptosis and cell cycle arrested at G2/M phase in a dose-dependent manner. In addition, two representative apoptosis-inducing cytotoxic agents were selected as positive control drugs to validate the reasonableness and accuracy of our metabolomic investigation on GLA. The study displayed a systemic metabolic alteration induced by GLA treatment, showing the impaired physiological activity of SMMC7721 cells, which also indicated anti-proliferative and apoptotic effects of GLA. In the meantime, GC/MS- and LC/MS-based metabolomics applied to cell culture enhanced our current understanding of the metabolic response to GLA treatment and its mechanism; such an approach could be transferred to study the mechanism of other anticancer drugs. Graphical abstract A systemic metabolic alteration induced by glaucocalyxin A (GLA) treatment of SMMC-7721 cells.

Rhizoma corydalis and Radix Angelicae Dahurica (Yuanhu–Baizhi) herbal medicine pair has been used for thousands of years and has been reported to be potentially active in recent cancer therapy. But the exact active components or fractions remain unclear. In this study, a new comprehensive two-dimensional (2D) 3-aminopropyltriethoxysilane (APTES)-decorated MCF7-cell membrane chromatography (CMC)/capcell-C18 column/time-of-flight mass spectrometry system was established for screening potential active components and clarifying the active fraction of Yuanhu–Baizhi pair. APTES was modified on the surface of silica, which can provide an amino group to covalently link cell membrane fragments with the help of glutaraldehyde in order to improve the stability and column life span of the MCF7 CMC column. The comprehensive 2D MCF7-CMC system showed good separation and identification abilities. Our screen results showed that the retention components are mainly from the alkaloids in Yuanhu (12 compounds) and the coumarins (10 compounds) in Baizhi, revealing the active fractions of Yuanhu–Baizhi herbal medicine pair. Oxoglaucine, protopine, berberine, osthole, isopimpinellin and palmitic acid were selected as typical components to test the effects on cell proliferation and their IC50 were calculated as 38.17 μM, 29.45 μM, 45.42 μM, 132.7 μM, 156.8 μM and 90.5 μM respectively. Cell apoptosis assay showed that the drug efficacy was obtained mainly through inducing cell apoptosis. Furthermore, a synergistic assay results demonstrated that oxoglaucine (representative of alkaloids from Yuanhu) and isopimpinellin (representative of coumarins from Baizhi) showed significant synergistic efficacy with GFT, indicating that these components may act on other membrane receptors. The proposed 2D CMC system could also be equipped with other cells for further applications. Besides, the follow-up in-vitro experimental strategy using cell proliferation assay, cell apoptosis assay and synergistic assay proved to be a practical way to confirm the active fractions of herbal medicine. Keywords: Cell membrane chromatography, Comprehensive two-dimensional chromatography, Herbal medicine, Rhizoma corydalis and Radix Angelicae Dahurica, Anti-breast-cancer components

Antidepressant drugs are widely used in the treatment of different psychiatric disorders, as well as in conjunction with antipsychotics for the treatment of major depressive disorder. In this study, a simple and rapid ultrasound-assisted low-density solvent dispersive liquid-liquid microextraction (UA-LDS-DLLME) method was developed for the simultaneous determination of 12 new antidepressants (norfluoxetine, fluoxetine, fluvoxamine, agomelatine, mirtazapine, moclobemide, melitracen, N-desmethylmirtazapine, maprotiline, sertraline, citalopram, paroxetine) and 2 antipsychotics (clozapine and haloperidol) in human whole blood by gas chromatography-mass spectrometry (GC-MS). Different parameters affecting the UA-LDS-DLLME were optimized and the optimal conditions were as follows: 100μL of toluene as extraction solvent, extraction pH 12 and 3min of ultrasound stirring. Good linearity (R2≥0.991) was obtained at the concentration range of 15-1500ng/mL for norfluoxetine, fluoxetine, fluvoxamine, melitracen, maprotiline and citalopram, and 5-500ng/mL for agomelatine, mirtazapine, moclobemide, N-desmethylmirtazapine, sertraline, paroxetine, clozapine and haloperidol. The intra-day and inter-day precision were all less than 10%, and accuracy of intra-day and inter-day were in the range of -12.7% to 7.9% and -13.9 to 11.8%, respectively. The extraction recoveries of most analytes were more than 60%. The UA-LDS-DLLME/GC-MS method was demonstrated with acceptable precision, accuracy and good specificity for the simultaneous determination of 12 antidepressants and 2 antipsychotics, and has been successfully applied in a real case.

Membrane proteins (MPs) are playing important roles in several biological processes. Screening new candidate compounds targeting MPs is important for drug discovery. However, it remains challenging to characterize the interactions between MPs and small-molecule ligands in a label-free method. In this study, a surface plasmon resonance (SPR)-based membrane protein-targeted active ingredients recognition strategy was constructed. This strategy contains two major modules: affinity detection module and ligand screening module. Through the combination of these two functional modules, it is feasible to screen small molecular ligands targeting MPs from herbal medicines. First, we have constructed high/low comparative C-X-C chemokine receptor type 4 (CXCR4)-expressed lentiviral particles (LVPs) models and characterized the expression levels. Then we immobilized LVPs on CM5 chips and detected the affinity between AMD3100 and CXCR4 by using affinity detection module. The KD of AMD3100 was 32.48 ± 3.17 nM. Furthermore, the suitability and robustness of the ligand screening module were validated by using AMD3100 as a positive compound. Subsequently, this module was applied in the screening of CXCR4 small molecular ligands from herbal medicine extracts. Senkyunolide I was screened out from Chuanxiong extract. The affinity constant between senkyunolide I and CXCR4 was 2.94 ± 0.36 μM. The Boyden chamber assay revealed that senkyunolide I could inhibit cell migration process. In conclusion, an SPR-based small molecular ligand recognition strategy combined with virus-based membrane protein stabilization method was constructed. The SPR-based membrane protein-targeted active ingredients recognition strategy will be an effective tool to screen target components from complex systems acting on MPs.

BACKGROUND: Acute graft versus host disease (aGvHD) is a major factor that limits the successful outcomes of allogeneic hematopoietic cell transplantation (alloHSCT). Currently, there are few validated biomarkers that can help predict the risk of aGvHD in clinical settings. METHODS: We performed an integrated metabolomics and transcriptomics study and identified biomarkers that distinguish alloHSCT recipients with aGvHD from alloHSCT recipients without aGvHD in 2 separate cohorts. RESULTS: Pathway analysis of 38 significantly altered metabolites and 1,148 differentially expressed genes uncovered a distinctly altered glycerophospholipid (GPL) metabolism network. Subsequently, we developed an aGvHD risk score (GRS) based on 5 metabolite markers from GPL metabolism to predict the risk of aGvHD. GRS showed a positive predictive value of 92.2% and 89.6% in the training and validation cohorts, respectively. In addition, high GRS was correlated with poor overall survival. Gene expressions of GPL-related lipases were significantly altered in aGvHD samples, leading to dysregulated GPLs. CONCLUSION: Using integrative “Omic” analysis, we unraveled a comprehensive view of the molecular perturbations underlying the pathogenesis of aGvHD. Our work represents an initial investigation of a unique metabolic and transcriptomic network that may help identify aGvHD at an early stage and facilitate preemptive therapy. FUNDING: National Natural Science Foundation of China (NSFC; 81530047, 81870143, 81470321, 81770160, 81270567, 81270638, 81573396, 81703674) provided funding for material, processing, metabolomics, and transcriptomics studies. This work was also supported by Shanghai Sailing Program from Science and Technology Commission Shanghai Municipality (17YF1424700), the Scholarship from Shanghai Municipal Health and Family Planning Commission (2017BR012), and the Special Clinical Research in Health Industry in Shanghai (20184Y0054). The projects supporting young scholars are 17YF1424700 (to YL), 2017BR012 (to XH), and 20184Y0054 (to QC).

Cell membrane chromatography (CMC) is an ideal method for screening potential active components acting on target cell membranes from a complex system, such as herbal medicines. But due to the decay and falling-off of membranes, the CMC column suffers from short life span and low reproducibility. This has greatly limited the application of this model, especially when the cell materials are hard to obtain. To solve this problem, a novel type of (3-aminopropyl)triethoxysilane (APTES)-decorated silica gel was employed. The silica gel was decorated with aldehydes with the help of APTES, which react with the amino groups on cell membranes to form a covalent bond. In this way, cell membranes were immobilized on the surface of silica gel, so it is not easy for membranes to fall off. According to our investigation, the column life of the APTES-decorated group was prolonged to more than 12 days, while the control group showed a sharp decline in column efficiency in the first 3 days. To verify this model, a novel APTES-decorated HepG2 cancer stem cell membrane chromatography (CSCMC) was established and applied in a comprehensive two-dimensional chromatographic system to screen potential active components in Salvia miltiorrhiza. As a result, tanshinone IIA, cryptotanshinone, and dihydrotanshinone I were retained on this model and proved to be effective on HepG2 cancer stem cells by the following cell proliferation and apoptosis assay, with IC

A sensitive and high-throughput chiral liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of R-pantoprazole and S-pantoprazole in human plasma. Sample extraction was carried out by using ethyl acetate liquid-liquid extraction in 96-well plate format. The separation of pantoprazole enantiomers was performed on a CHIRALCEL OJ-RH column and an overlapping injection mode was used to achieve a run time of 5.0 min/sample. The mobile phase consisted of 1) 10 mM ammonium acetate in methanol: acetonitrile (1:1, v/v) and 2) 20 mM ammonium acetate in water. Isocratic elution was used with flow rate at 500 μL/min. The enantiomers were quantified on a triple-quadrupole mass spectrometer under multiple reaction monitoring (MRM) mode with m/z 382.1/230.0 for pantoprazole and m/z 388.4/230.1 for pantoprazole-d7. Linearity from 20.0 to 5000 ng/mL was established for each enantiomer (r(2) > 0.99). Extraction recovery ranged from 91.7% to 96.4% for R-pantoprazole and from 92.5% to 96.5% for S-pantoprazole and the IS-normalized matrix factor was 0.98 to 1.07 for R-pantoprazole and S-pantoprazole, respectively. The method was demonstrated with acceptable accuracy, precision, selectivity, and stability and the method was applied to support a pharmacokinetic study of a phase I clinical trial of racemic pantoprazole in healthy Chinese subjects. Chirality 28:569-575, 2016. © 2016 Wiley Periodicals, Inc.

Background Primary liver cancer (PLC) is one of the most common malignant tumors world-wide but its pathogenesis is unclear. We suggest that steroid hormones may offer diagnostic information for PLC. Methods Using liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS), we quantified 7 endogenous steroids in 66 PLC human serum samples, 59 liver cirrhosis (LC) samples, and 65 healthy volunteers (HV). Data were assessed chemometrically and with Mann-Whitney U tests and partial least squares discriminant analysis (PLS-DA). Results For PLC patients, androgens were low and estrogen was high. PLS-DA analysis discriminated between healthy subjects and cancer patients using (estrone + estradiol)/testosterone ratios. Moreover, cirrhosis patients were also distinguished with receiver operating characteristic curves indicating the specificity and sensitivity of our current approach. Conclusions Steroid hormone profiling by UPLC-MS/MS may be promising for early diagnosis of PLC but investigations with more patients and steroids are required to confirm the utility of these biomarkers for clinical applications.

To accelerate the discovery of anti-cancer drugs, there is an urgent need to establish an inexpensive and simple preclinical model that can simulate the tumor microenvironment and screen the drug candidates. Some widely used screening platforms are high-cost and over-simple to verify the cell-drug interactions for predicting human clinical trial outcomes. As a promising technology, microfluidic chip can replace traditional screening methods due to low reagent consumption and the capability of recapitulating the 3D cell culture more representative of the native tumor microenvironment. This review covers the materials for microchip fabrication (especially hydrogel), tumor microenvironment, 2D and 3D tumor culture on chips, drug screening methods (concentration gradient generator-based, microdroplet-based, microarray-based chips, and tumor tissue chip), and their pros and cons for cancer treatment. We also discuss the future development of microfluidic for anti-cancer drug discovery research.

Tea polyphenols (TP) are the major antioxidant components from tea, which could be beneficial to oxidative stress injury, such as sulfur mustard (SM) exposure. However, the holistic efficacy of TP on SM poisoning remains unexplored and needs further investigation. In this study, Nuclear magnetic resonance(NMR)-based metabolomics along with multivariate statistical analysis was used to explore the metabolic alteration after SM injury and the protective mechanism of TP. Thirteen potential plasma biomarkers of SM injury were identified, which primarily related to synthesis of ketone bodies, arginine and proline metabolism, butanoate metabolism and alanine aspartate and glutamate metabolism. After TP pre-treatment, the biomarkers were mostly restored to normal levels, which suggested that TP provided effective protection against SM injury and might play its role by rebalancing disordered metabolism pathways. This work enhanced our comprehension of the metabolic profiling of SM injury and revealed the protective mechanism of TP.

Alzheimer’s disease (AD) is a chronic neurodegenerative disorder with neither definitive pathogenesis nor effective therapy so far. Danshen, the dried root and rhizome of Salvia miltiorrhiza Bunge, is used extensively in Alzheimer’s disease treatment to ameliorate the symptoms, but the underlying mechanism remains to be clarified. To investigate potential biomarkers for AD and elucidate the protective mechanism of Danshen on AD cell model. An ultra high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-QTOF/MS)-based approach combined with partial least squares discriminant analysis (PLS-DA) has been developed to discriminate the metabolic modifications between human brain microvascular endothelial cell (hBMEC) and AD cell model induced by amyloid-β protein (Aβ1–42). To further elucidate the pathophysiology of AD, related metabolic pathways have been studied. Thirty-three distinct potential biomarkers were screened out and considered as potential biomarkers corresponding to AD, which were mostly improved and partially restored back to normalcy in Danshen pre-protection group. It was found that AD was closely related to disturbed arginine and proline metabolism, glutathione metabolism, alanine aspartate and glutamate metabolism, histidine metabolism, pantothenate and CoA biosynthesis, phenylalanine tyrosine and tryptophan biosynthesis, citrate cycle and glycerophospholipid metabolism, and the protective mechanism of Danshen in AD cell model may be related to partially regulating the perturbed pathways. These outcomes provide valuable evidences for therapeutic mechanism investigation of Danshen in AD treatment, and such an approach could be transferred to unravel the mechanism of other traditional Chinese medicine (TCM) and diseases.

Alzheimer's disease (AD) is a chronic neurodegenerative disorder with neither definitive pathogenesis nor effective therapy so far. Danshen, the dried root and rhizome of Salvia miltiorrhiza Bunge, is used extensively in Alzheimer's disease treatment to ameliorate the symptoms, but the underlying mechanism remains to be clarified.To investigate potential biomarkers for AD and elucidate the protective mechanism of Danshen on AD cell model.An ultra high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-QTOF/MS)-based approach combined with partial least squares discriminant analysis (PLS-DA) has been developed to discriminate the metabolic modifications between human brain microvascular endothelial cell (hBMEC) and AD cell model induced by amyloid-β protein (AβThirty-three distinct potential biomarkers were screened out and considered as potential biomarkers corresponding to AD, which were mostly improved and partially restored back to normalcy in Danshen pre-protection group. It was found that AD was closely related to disturbed arginine and proline metabolism, glutathione metabolism, alanine aspartate and glutamate metabolism, histidine metabolism, pantothenate and CoA biosynthesis, phenylalanine tyrosine and tryptophan biosynthesis, citrate cycle and glycerophospholipid metabolism, and the protective mechanism of Danshen in AD cell model may be related to partially regulating the perturbed pathways.These outcomes provide valuable evidences for therapeutic mechanism investigation of Danshen in AD treatment, and such an approach could be transferred to unravel the mechanism of other traditional Chinese medicine (TCM) and diseases.

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method based on amylose derivatives as chiral stationary phases (CSPs) for the chiral separation of four

The aim was to evaluate the effects of tetrahydropalmatine (THP) enantiomers on the activity of five cytochrome P450 (CYP450) isozymes in vivo. A liquid chromatography / mass spectrometric (LC-MS) method was developed for simultaneous determination of five specific probe substrates including metoprolol (2D6), caffeine (1A2), dapsone (3A4), chlorzoxazone (2E1), and tolbutamide (2C9) in rat plasma. Analytes were separated with the mobile phase consisting of 0.1% acetic acid aqueous solution and acetonitrile in a gradient elution. The mass spectrometric detection via selected ion monitoring (SIM) was operated in both positive ion mode (for metoprolol m/z 268, caffeine m/z 195, and dapsone m/z 249) and negative ion mode (for chlorzoxazone m/z 168 and tolbutamide m/z 269) in the same run. Linear correlation was obtained (r2 > 0.99) over the concentration range of 0.050–25.0 µg/mL for caffeine and dapsone, 0.025–10.0 µg/mL for metoprolol, 0.050–50.0 µg/mL for chlorzoxazone, and 0.25–100.0 µg/mL for tolbutamide. Intra- and interday precision were less than 12.09%. The matrix effect ranged from 87.50% to 109.25% and the absolute recoveries were greater than 70%. The method was successfully applied to evaluate the effect of THP enantiomers on the activity of CYP450 isozymes by a cocktail approach. The pharmacokinetic results of five probe drugs indicated that there were stereoselective differences between the two THP enantiomers, i.e., d-THP had the potential to inhibit the activities of CYP2D6 and CYP1A2 isozymes, while l-THP inhibited CYP1A2 isozyme and induced CYP3A4 and CYP2C9 isozymes. Chirality 27:551–556, 2015. © 2015 Wiley Periodicals, Inc.

As one of the most troublesome complications in patients with chronic renal disease, the etiology of uremic pruritus remains unknown, and the current therapeutic approaches are limited and unsatisfactory. To identify potential biomarkers for improving diagnosis and treatment and obtain a better understanding of the pathogenesis of uremic pruritus, we compared serum metabolome profiles of severe uremic pruritus (HUP) patients with mild uremic pruritus (LUP) patients using ultraperformance liquid chromatography-quadruple time-of-flight mass spectrometry (UPLC-QTOF MS). Partial least squares discriminant analysis (PLS-DA) showed that the metabolic profiles of HUP patients are distinguishable from those of LUP patients. Combining multivariate with univariate analysis, 22 significantly different metabolites between HUP and LUP patients were identified. Nine of the 22 metabolites in combination were characterized by a maximum area-under-receiver operating characteristic curve (AUC = 0.899) with a sensitivity of 85.1% and a specificity of 83.0% distinguishing HUP and LUP. Our results indicate that serum metabolome profiling might serve as a promising approach for the diagnosis of uremic pruritus and that the identified biomarkers may improve the understanding of pathophysiology of this disorder. Because the 9 metabolites were phospholipids, uremic toxins, and steroids, further studies may reveal their possible role in the pathogenesis of uremic pruritus.

A rapid, sensitive and selective liquid chromatography with tandem mass spectrometry method was developed and fully validated for the simultaneous quantification of arotinolol and amlodipine in rat plasma. Two internal standards were introduced with metoprolol as the internal standard of arotinolol and (S)-amlodipine-d4 as the internal standard of amlodipine. The analytes were isolated from 50.0 μL plasma samples by a simple protein precipitation using acetonitrile. The chromatographic separation was achieved in 5 min on a C18 column. The mobile phase consisted of phase A 5% methanol and phase B 95% methanol (both containing 0.5% formic acid and 5 mM ammonium acetate) and was delivered in gradient elution at 0.300 mL/min. Quantification was performed in multiple-reaction-monitoring mode with the transition m/z 372.1 → 316.1 for arotinolol, m/z 268.2 → 116.2 for metoprolol, m/z 409.1 → 238.1 for amlodipine and m/z 413.1 → 238.1 for (S)-amlodipine-d4. Linearity was obtained over the range of 0.200–40.0 ng/mL for arotinolol (r2 = 0.9988) and 0.500–100 ng/mL for amlodipine (r2 = 0.9985) in rat plasma. The validated data have met the acceptance criteria in FDA guideline. This method was successfully applied to a pharmacokinetic interaction study in rats, and the results indicated that there was no significant drug–drug interaction between arotinolol and amlodipine. This article is protected by copyright. All rights reserved

Hyperlipidemia is considered to be a high lipid level in blood, can induce metabolic disorders and dysfunctions of the body, and results in some severe complications. Therefore, hunting for some metabolite markers and clarifying the metabolic pathways in vivo will be an important strategy in the treatment and prevention of hyperlipidemia. In this study, a rat model of hyperlipidemia was constructed according to histopathological data and biochemical parameters, and the metabolites of serum and urine were analyzed by UPLC-Q-TOF/MS. Combining pattern recognition and statistical analysis, 19 candidate biomarkers were screened and identified. These changed metabolites indicated that during the development and progression of hyperlipidemia, energy metabolism, lipid metabolism, amino acid metabolism and nucleotide metabolism were mainly disturbed, which are reported to be closely related to diabetes, cardiovascular diseases, etc. This study demonstrated that a UPLC-Q-TOF/MS based metabolomic approach is useful to profile the alternation of endogenous metabolites of hyperlipidemia. Keywords: UPLC-Q-TOF/MS, Hyperlipidemia, Metabolomic, Pattern recognition

A rapid and sensitive liquid chromatography with tandem mass spectrometry method has been developed and validated for the simultaneous quantification of 11 major compounds in Yuanhu-Bazhi herb-pair from a rat intestinal perfusion experiment, including eight alkaloids and three coumarins using diazepam as the internal standard. The analysis was performed on an Agilent Poroshell 120EC-C18 column using a gradient elution of acetonitrile/H2O with 0.0015% formic acid and 2 mM ammonium formate buffer additive (pH 4.2). All compounds were detected by tandem mass spectrometry in positive ionization mode and quantified using multiple reaction monitoring mode. Good linearity in the related range of each compound was presented. The validation data, such as accuracy and precision, were within the required limits. The lower limit of quantification of each analyte was less than 10 ng/mL. Intra-day and inter-day precisions were less than 12.84%. The relative errors of accuracy were in the range of –13.31 to 13.19%. The recoveries of analytes were greater than 84.08%. The method has been successfully applied to an intestinal absorption study of major components following intestinal perfusion of Yuanhu-Bazhi herb-pair extract to rats.

Cell membrane chromatography (CMC) derived from pathological tissues is ideal for screening specific components acting on specific diseases from complex medicines owing to the maximum simulation of in vivo drug-receptor interactions. However, there are no pathological tissue-derived CMC models that have ever been developed, as well as no visualized affinity comparison of potential active components between normal and pathological CMC columns. In this study, a novel comparative normal/failing rat myocardium CMC analysis system based on online column selection and comprehensive two-dimensional (2D) chromatography/monolithic column/time-of-flight mass spectrometry was developed for parallel comparison of the chromatographic behaviors on both normal and pathological CMC columns, as well as rapid screening of the specific therapeutic agents that counteract doxorubicin (DOX)-induced heart failure from Acontium carmichaeli (Fuzi). In total, 16 potential active alkaloid components with similar structures in Fuzi were retained on both normal and failing myocardium CMC models. Most of them had obvious decreases of affinities on failing myocardium CMC compared with normal CMC model except for four components, talatizamine (TALA), 14-acetyl-TALA, hetisine, and 14-benzoylneoline. One compound TALA with the highest affinity was isolated for further in vitro pharmacodynamic validation and target identification to validate the screen results. Voltage-dependent K(+) channel was confirmed as a binding target of TALA and 14-acetyl-TALA with high affinities. The online high throughput comparative CMC analysis method is suitable for screening specific active components from herbal medicines by increasing the specificity of screened results and can also be applied to other biological chromatography models.

The compatibility of Rhizoma Corydalis(Yuanhu,YH) and Radix Angelicae dahuricae (Baizhi,BZ) as a herb pair Yuanhu-Baizhi(YB) can produce synergistic analgesic effect. However, the underlying mechanism of this herb pair compatibility is not elucidated yet. A LC–MS/MS method combined with in vivo microdialysis sampling from awaken rats’ striatum was developed to simultaneously quantitate three endogenous neurotransmitters, dopamine(DA), glutamate (Glu), and 5-hydroxytryptamine (5-HT), and nine components of Yuanhu-Baizhi herb pair in rats. The microdialysates were derivatizated with benzoyl chloride and analyzed on Agilent Poroshell 120EC-C18 column. The mobile phase consisted of aqueous solution with 0.05% formic acid and 2.0 mM ammonium formate (A), and acetonitrile (B) delivered at gradient elution. All the twelve analytes were quantified using an electrospray ionization tandem mass spectrometry in the selective reaction monitoring mode. The method was validated following FDA’s guidance on bioanalytical validation. The standard curves were linear ( r2 > 0.991) over the corresponding concentration ranges. For three neurotransmitters, the intra-day and inter-day precision (RSD) were not greater than 14.9%, and the intra-day and inter-day accuracy (RE) ranged from -14.2∼ 7.2%. The LLOQ of 5-HT, DA and Glu were 0.50 nM, 0.50 nM and 20.00 nM, respectively. For nine components in Yuanhu-Baizhi herb pair, the intra-day and inter-day precision (RSD) were less than 15.0%, and the intra-day and inter-day accuracy (RE) ranged from -12.5 ∼14.8%. The novel developed method was applied to pharmacokinetic (PK) and pharmacodynamic (PD) study of Yuanhu-Baizhi herb pair in rats. The results showed that the pharmacokinetic behavior of nine components in the herb pair was significantly different with that of single herb, mainly referring to the bioavailability of five alkaloids from Yuanhu increased whereas that of four coumarins decreased in rat striatum. Pharmacodynamic study based on Glu, DA, and 5-HT revealed that the content of neurotransmitters varied when rats were administered Yuanhu-Baizhi herb pair or single herb. PD analysis results demonstrated the compatibility of Yuanhu and Baizhi has the synergistic effect and the effect of attenuation from the point of the neurotransmitters’ view. In conclusion, the pharmacokinetic and pharmacodynamic study based on in vivo microdialysis sampling from awaken animals and LC–MS/MS quantitation is in favor of revealing the compatibility mechanism of herb pairs.