A combined cell membrane chromatography and online HPLC/MS method for screening compounds from Radix Caulophylli acting on the human α1A-adrenoceptor

Immobilized protein strategies based on cell membrane chromatography and its application in discovering active and toxic substances in traditional Chinese medicine

Traditional Chinese medicine (TCM) contributes significantly to human health. Owing to the complexity of the ingredients in TCM, it is necessary to conduct basic research on effective substances and identify toxic substances to control the safety of medication. Cell membrane chromatography (CMC) is an important method for identifying target components in complex systems. The cell membrane stationary phase (CMSP) is the core component and key factor in determining the effectiveness of CMC. This review summarizes the development of CMSP with different membrane protein immobilization strategies and the application of CMC in the discovery of active and toxic substances in TCM, with the aim of providing an effective means for the discovery of active ingredients and quality control of TCM.

Application progress of immobilized biomembrane in the discovery of active compounds of natural products

Natural products (NPs) are an important source of bioactive compounds. Considering their complex matrix effects, the development of suitable methodologies for the fast identification and analysis of active substances from NPs played a significant role in controlling their quality and discovering new drugs. In recent years, the technology of immobilized biomembrane has attracted increasing attention, due to its peculiarities such as multi-target efficiency, accuracy and/or time-saving compared with traditional activity-guided separation and ligand fishing methods. This article first provides a systematic review of the latest advances in screening technologies based on biomembrane in the field of NPs. It includes detailed discussions of these technologies, including cell membrane chromatography, artificial membrane chromatography, cell membrane fishing, living cell fishing methods, and their applications in screening various active molecules from NPs. Their limitations and future development prospects were further discussed.

Ligand fishing via a monolithic column coated with white blood cell membranes: A useful technique for screening active compounds in Astractylodes lancea

The cell membrane-coated monolithic column (CMMC) ligand fishing assay is an interesting approach set up for the study of natural products (NPs). NPs such as Atractylodes lancea contain many compounds. Traditional methods used to separate compounds and determine active compounds by pharmacological tests are time-consuming and inefficient. Therefore, an alternative method is required to determine active compounds in NPs. Here, white blood cells were broken, and the white blood cell membranes (WBCMs) were immobilized on the surface of a monolithic column to form a CMMC. The column was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and confocal laser scanning microscopy. Combined with gas chromatography/mass spectrometry (GC/MS), the CMMC was used to screen active compounds in Atractylodes lancea. Three potential active compounds including hinesol, β-eudesmol, and 4-phenylbenzaldehyde were discovered. A molecular docking assay demonstrated that these compounds could bind to MD-2 laid on WBCMs. In addition, antiinflammatory effects by the discovered compound in vitro were confirmed, and β-eudesmol showed a concentration-dependent inhibitory effect on the tumor necrosis factor (TNF)-α of a RAW264.7 cell (P < 0.05). The CMMC ligand fishing assay exhibits good selectivity, great speed effects and is a potentially reliable tool for drug discovery in NPs.

Analysis of bioactive components and pharmacokinetics of Caulophyllum robustum in rat plasma after oral administration by UPLC-ESI-MS/MS

A UPLC-MS/MS method was developed and validated the determination and pharmacokinetic study of magnoflorine, cauloside C, hederagenin, and oleanolic acid from Caulophyllum robustum. Digoxin was used as the internal standard. The pretreated plasma samples were carried out on a Waters ACQUITYUPLC HSS T3 column at 35 °C with a mobile phase of acetonitrile-water (90:10, v/v) at a flow rate of 0.2 mL/min. This article describes the most simple, sensitive, and validated UPLC-MS/MS method to date for the simultaneous successful determination of four compounds in rat plasma after oral administration of the extract of C. robustum and their pharmacokinetic studies.

Advances in cell membrane chromatography

Cell membrane chromatography (CMC) is a biomimetic chromatographic method based on the ability of membrane receptors to selectively interact with their ligands in vivo. Using membrane receptors as a stationary phase, the CMC method helps in determining the binding characteristics between ligands and membrane receptors and in efficiently identifying specific target components in a complex sample that produce the cellular biological effects of ligands (drugs, antibodies, enzymes, cytokines, etc.). CMC is an analytical tool for revealing characteristics of ligand-receptor interactions, screening and discovering target substances, and accurately controlling the quality of drugs. Since establishment of CMC in the early 1990s, with the rapid development of cell biology, significant progress has been made in the development of high-expression receptors, engineered cell cultures, and standardized preparations, which allowed in vitro immobilization of cell membrane receptors and miniaturization of binding assays. A variety of CMC models have been established using different membrane receptors as a stationary phase, and many new methods have been developed by combining CMC with high-performance liquid chromatography (HPLC)/mass spectrometry or HPLC-IT-TOF technologies. CMC methods have been widely used to study drug-receptor interactions and to screen complex samples for effective or harmful components.

Screening techniques for the identification of bioactive compounds in natural products

Natural products (NPs) have a long history of clinical use and are rich source of bioactive compounds. The development of tools and techniques for identifying and analyzing NP bioactive compounds to ensure their quality and discover new drugs is thus very important and still in demand. Screening techniques have proven highly useful for screening and analyzing active components in complex mixtures, which rely on cell culture, dialysis, ultrafiltration, chromatographic methods and target molecule immobilization, using biological targets to identify the active compounds. The recent progress in biological screening techniques in the field of natural products is reviewed here. This includes a review on the strategy and application of the screening methods, their detailed description and discussion of their existing limitations of the different models along with prospective in future development of screening techniques.

Analysis of solute-protein interactions and solute-solute competition by zonal elution affinity chromatography

Many biological processes involve solute-protein interactions and solute-solute competition for protein binding. One method that has been developed to examine these interactions is zonal elution affinity chromatography. This review discusses the theory and principles of zonal elution affinity chromatography, along with its general applications. Examples of applications that are examined include the use of this method to estimate the relative extent of solute-protein binding, to examine solute-solute competition and displacement from proteins, and to measure the strength of these interactions. It is also shown how zonal elution affinity chromatography can be used in solvent and temperature studies and to characterize the binding sites for solutes on proteins. In addition, several alternative applications of zonal elution affinity chromatography are discussed, which include the analysis of binding by a solute with a soluble binding agent and studies of allosteric effects. Other recent applications that are considered are the combined use of immunoextraction and zonal elution for drug-protein binding studies, and binding studies that are based on immobilized receptors or small targets.

Screening of bioactive components from traditional Chinese medicines using cell membrane chromatography coupled with mass spectrometry

INTRODUCTION

Cell membrane chromatography (CMC), as a highly selective type of affinity chromatography, has been demonstrated as an effective method to screen bioactive components acting on specific receptor from a complicated biological system.

OBJECTIVE

To review the recent research progress and the technical applications of these analytical methods using CMC combined with gas chromatography-mass spectrometry, (GC/MS) and liquid chromatography-mass spectrometry (LC/MS).

METHODOLOGY

In this review, we briefly introduce the CMC offline GC/MS, CMC online GC/MS, CMC offline LC/MS, and CMC online LC/MS system. And the practical application of these technologies is also enumerated. Then the future of these technologies and research methods were discussed.

RESULTS

Many bioactive components interacting with specific receptors have been screened and identified in traditional Chinese medicines.

CONCLUSION

CMC technique has been combined with GC/MS and HPLC/MS and these combined systems have been successfully used to screen bioactive components acting on specific receptors from a complicated biological system.

A method for screening active components from Chinese herbs by cell membrane chromatography-offline-high performance liquid chromatography/mass spectrometry and an online statistical tool for data processing

Cell membrane chromatography (CMC) has been successfully applied to screen bioactive compounds from Chinese herbs for many years, and some offline and online two-dimensional (2D) CMC-high performance liquid chromatography (HPLC) hyphenated systems have been established to perform screening assays. However, the requirement of sample preparation steps for the second-dimensional analysis in offline systems and the need for an interface device and technical expertise in the online system limit their extensive use. In the present study, an offline 2D CMC-HPLC analysis combined with the XCMS (various forms of chromatography coupled to mass spectrometry) Online statistical tool for data processing was established. First, our previously reported online 2D screening system was used to analyze three Chinese herbs that were reported to have potential anti-inflammatory effects, and two binding components were identified. By contrast, the proposed offline 2D screening method with XCMS Online analysis was applied, and three more ingredients were discovered in addition to the two compounds revealed by the online system. Then, cross-validation of the three compounds was performed, and they were confirmed to be included in the online data as well, but were not identified there because of their low concentrations and lack of credible statistical approaches. Last, pharmacological experiments showed that these five ingredients could inhibit IL-6 release and IL-6 gene expression on LPS-induced RAW cells in a dose-dependent manner. Compared with previous 2D CMC screening systems, this newly developed offline 2D method needs no sample preparation steps for the second-dimensional analysis, and it is sensitive, efficient, and convenient. It will be applicable in identifying active components from Chinese herbs and practical in discovery of lead compounds derived from herbs.

An insertion/self-fusion mechanism for cell membrane immobilization on porous silica beads to fabricate biomimic carriers

An insertion/self-fusion mechanism for cell membrane immobilization on porous silica beads has been proposed to fabricate biomimic carriers.

Screening anaphylactic components of MaiLuoNing injection by using rat basophilic leukemia-2H3 cell membrane chromatography coupled with HPLC-ESI-TOF-MS

MaiLuoNing injection is a traditional Chinese medicine that used clinically since the 1950s in China. However, anaphylactic reactions, through the potentiation of mast cell degranulation, have been reported. In the present study, a rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization-ion trap-time of flight-mass spectrometry method was established for screening, analyzing, and identifying the potential anaphylactic components of MaiLuoNing injection. Harpagoside, a potential degranulator of rat basophilic leukemia-2H3 cells, was retained in rat basophilic leukemia-2H3 cell membrane chromatography. We aimed to evaluate the retained components to determine which of those were capable of inducing degranulation of basophilic leukemia cells. A β-hexosaminidase assay revealed that harpagoside can induce rat basophilic leukemia-2H3 cell degranulation in a dose-dependent manner. BLBA/c mice also exhibit passive cutaneous anaphylaxis in response to harpagoside. These results indicate that rat basophilic leukemia-2H3 cell membrane chromatography coupled with high-performance liquid chromatography and electrospray ionization ion trap time-of-flight mass spectrometry is effective in screening for the anaphylactic components of MaiLuoNing injection.

Characterization of anti-leukemia components from Indigo naturalis using comprehensive two-dimensional K562/cell membrane chromatography and in silico target identification

Traditional Chinese Medicine (TCM) has been developed for thousands of years and has formed an integrated theoretical system based on a large amount of clinical practice. However, essential ingredients in TCM herbs have not been fully identified, and their precise mechanisms and targets are not elucidated. In this study, a new strategy combining comprehensive two-dimensional K562/cell membrane chromatographic system and in silico target identification was established to characterize active components from Indigo naturalis, a famous TCM herb that has been widely used for the treatment of leukemia in China, and their targets. Three active components, indirubin, tryptanthrin and isorhamnetin, were successfully characterized and their anti-leukemia effects were validated by cell viability and cell apoptosis assays. Isorhamnetin, with undefined cancer related targets, was selected for in silico target identification. Proto-oncogene tyrosine-protein kinase (Src) was identified as its membrane target and the dissociation constant (Kd) between Src and isorhamnetin was 3.81 μM. Furthermore, anti-leukemia effects of isorhamnetin were mediated by Src through inducing G2/M cell cycle arrest. The results demonstrated that the integrated strategy could efficiently characterize active components in TCM and their targets, which may bring a new light for a better understanding of the complex mechanism of herbal medicines.

Interactions between histamine H1 receptor and its antagonists by using cell membrane chromatography method

Objectives

A high histamine H1 receptor (H1R) expression cell membrane chromatography (CMC) method was developed to investigate the affinity of ligands for H1R.

Methods

The affinity of ligands for H1R was evaluated by frontal analysis. Competition studies and molecular docking study were utilized to study the interactions that occurred at specific binding sites on H1R.

Key findings

The KD values measured by frontal analysis were (8.72 ± 0.21) × 10−7 M for azelastine, (9.12 ± 0.26) × 10−7 M for cyproheptadine, (9.90 ± 0.18) × 10−7 M for doxepin, (1.42 ± 0.13) × 10−6 M for astemizole, (2.25 ± 0.36) × 10−6 M for chlorpheniramine and (3.10 ± 0.27) × 10−6 M for diphenhydramine. The results had a positive correlation with those from radioligand binding assay. The ability of displacement order measured on the binding sites occupied by doxepin was doxepin (KD, (2.95 ± 0.21) × 10−8 M) &gt; astemizole (KD, (5.03 ± 0.18) × 10−7 M) &gt; chlorpheniramine (KD, (1.27 ± 0.16) × 10−6 M) &gt; cyproheptadine (KD, (1.61 ± 0.27) × 10−6 M), whose order met with the scores by molecular docking study.

Conclusions

The studies showed CMC could be applied to investigate drug–receptor interactions.

Combining Sprague-Dawley rat uterus cell membrane chromatography with HPLC/MS to screen active components from Leonurus artemisia

CONTEXT

Leonurus artemisia (Lour.) S.Y.Hu (Lamiaceae) (YiMuCao in Chinese) is a traditional Chinese medicine. Leonurus artemisia has been shown to have many pharmacological effects such as increasing uterine contraction amplitude, and tension, but the active components are still unknown.

OBJECTIVE

The objective of this study is to determine active components of L. Artemisia that are responsible for the biological activity using HPLC and cell membrane-based system.

MATERIALS AND METHODS

The whole L. artemisia ethanol extract and its eight fractions were screened using Sprague-Dawley rat uterus cell membrane chromatography (CMC) combined with the HPLC/MS system. Oxytocin was used to investigate the activity of CMC column. The effect of active components screened from L. artemisia was studied by tension measurement of isolated rat uterine strips in vitro at a dose of 10(-7)-10(-4 )mol/L with oxytocin as a control.

RESULTS

The acetone extract showed obvious activity when compared with the eight extracts of L. artemisia. From the acetone extract, in the negative ionization mode, the active compound was identified as genkwanin, with a molecular weight of 283. In vitro pharmacological experiments proved that genkwanin promoted uterine contractions at a dose from 10(-7) to 10(-4 )mol/L. The EC50 value was 4.86 ± 4.21 μmol/L for genkwanin and 4.30 ± 3.65 μmol/L for oxytocin on the contractile amplitude of uterine strips isolated from rats.

DISCUSSION AND CONCLUSION

Genkwanin was identified as the active compound in L. artemisia by this method. In vitro pharmacological experiments proved that genkwanin promoted uterine contractions. Genkwanin may be used to uterine inertia and may have an effect on postpartum hemorrhage.

Prospects for multitarget lipid-raft-coated silica beads: a remarkable online biomaterial for discovering multitarget antitumor lead compounds

Application of lipid raft biomaterial with multiple cancer-related receptors for screening novel multitarget antitumour lead compounds.

Genus caulophyllum: an overview of chemistry and bioactivity

Recently, some promising advances have been achieved in understanding the chemistry, pharmacology, and action mechanisms of constituents from genus Caulophyllum. Despite this, there is to date no systematic review of those of genus Caulophyllum. This review covers naturally occurring alkaloids and saponins and those resulting from synthetic novel taspine derivatives. The paper further discussed several aspects of this genus, including pharmacological properties, mechanisms of action, pharmacokinetics, and cell membrane chromatography for activity screening. The aim of this paper is to provide a point of reference for pharmaceutical researchers to develop new drugs from constituents of Caulophyllum plants.

Comparative normal/failing rat myocardium cell membrane chromatographic analysis system for screening specific components that counteract doxorubicin-induced heart failure from Acontium carmichaeli

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.

Isolation and characterization of bioactive compounds from plant resources: the role of analysis in the ethnopharmacological approach

The phytochemical research based on ethnopharmacology is considered an effective approach in the discovery of novel chemicals entities with potential as drug leads. Plants/plant extracts/decoctions, used by folklore traditions for treating several diseases, represent a source of chemical entities but no information are available on their nature. Starting from this viewpoint, the aim of this review is to address natural-products chemists to the choice of the best methodologies, which include the combination of extraction/sample preparation tools and analytical techniques, for isolating and characterizing bioactive secondary metabolites from plants, as potential lead compounds in the drug discovery process. The work is distributed according to the different steps involved in the ethnopharmacological approach (extraction, sample preparation, biological screening, etc.), discussing the analytical techniques employed for the isolation and identification of compound/s responsible for the biological activity claimed in the traditional use (separation, spectroscopic, hyphenated techniques, etc.). Particular emphasis will be on herbal medicines applications and developments achieved from 2010 up to date.

High-expression EGFR/cell membrane chromatography-online-high-performance liquid chromatography/mass spectrometry: rapid screening of EGFR antagonists from Semen Strychni

RATIONALE

Traditional methods for screening active compounds from complex system such as traditional Chinese medicines are relatively cumbersome and time-consuming. In order to improve this situation, we established an online analytical method for screening, separation and identification EGFR antagonists from traditional Chinese medicines, which is described in this study.

METHODS

Cells with high EGFR expression levels were used to prepare the cell membrane stationary phase for the EGFR cell membrane chromatography model with the purpose of screening active compounds. Separation of the retention fractions was achieved by the high-performance liquid chromatography, and identification was conducted via electrospray ionization quadrupole mass spectrometry. The inhibitory effects of active compounds on EGFR cell growth were also demonstrated in vitro.

RESULTS

The screening results showed that vauquline and strychnine from Semen Strychni could be active components acting on EGFR similarly to gefitinib as a control drug. Results from biological trials showed that vauquline and strychnine inhibited cell proliferation of HEK293/EGFR cells, and inhibited Erk phosphorylation, and can effectively reduce expression of downstream signaling molecules.

CONCLUSIONS

This EGFR cell membrane chromatography-online-high-performance liquid chromatography/tandem mass spectrometry method can be applied for rapid screening, separation and identification of EGFR antagonists from traditional Chinese medicines and should be useful for drug discovery with natural medicinal herbs.

An Escherichia coli Cell Membrane Chromatography-Offline LC-TOF-MS Method for Screening and Identifying Antimicrobial Peptides from Jatropha curcas Meal Protein Isolate Hydrolysates

A novel, simple, and rapid method, named cell membrane affinity extraction (CMAE)–offline liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) was developed for screening and identifying antimicrobial peptides from Jatropha curcas meal protein isolate hydrolysates (JCMPIH) obtained by proteolytic enzyme (pepsin, trypsin, protamex, neutrase, flavourzyme, papain, alcalase, and acid protease) hydrolysis. A cationic antimicrobial peptide (CAILTHKR, JCpep8) was successfully isolated and identified by this method. Antimicrobial assay indicated that JCpep8 was active against the tested microorganisms ( Escherichia coli ATCC 25922, Shigella dysenteriae ATCC 51302, Pseudomonas aeruginosa ATCC 27553, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 23631, Streptococcus pneumoniae ATCC 49619) with minimal inhibitory concentration values ranging from 29 to 68 µg/mL. JCpep8 induced significant morphological alterations of the tested microbe surfaces, as shown by transmission electron microscopy, indicating strong membrane disruption. The results showed that CMAE-offline LC-TOF-MS could be a promising method for discovering high-throughput screening antimicrobial peptides from JCMPIH.

Applications of HPLC/MS in the analysis of traditional Chinese medicines

In China, traditional Chinese medicines (TCMs) have been used in clinical applications for thousands of years. The successful hyphenation of high-Performance liquid chromatography (HPLC) and mass spectrometry (MS) has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most populär type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere.

Using cell membrane chromatography and HPLC-TOF/MS method for in vivo study of active components from roots of Aconitum carmichaeli

An offline two-dimensional system combining a rat cardiac muscle cell membrane chromatography time-of-flight mass spectrometry (CMC-TOF/MS) with a high Performance liquid chromatography time-of-flight mass spectrometry (HPLC-TOF/MS) was established for investigating the parent components and metabolites in rat urine samples after administration of the roots of Aconitum carmichaeli. On the basis ofthe analysis of the first dimension, retention components of the urine sample were collected into 30 fractions (one fraction per minute). Then offline analysis of the second dimension was carried out. 34 compounds including 24 parent alkaloids and 10 potential metabolites were identified from the dosed rat urine, and then binding affinities of different compounds on cell membranes were compared and influences of some functional groups on activity were estimated with the semi-quantification and curve fitting method. As a result, binding affinities decreased along with the process of deacylation, debenzoylation and demethylation, which may be related to the alleviation of toxicity in the procedure of herb processing or metabolism. Moreover, some minor components in rat urine (Songorine, 14-benzoylneoline, Deoxyaconitine, etc.) exerted relatively strong affinity on cell membranes are worth exploring. The results delivered by the System suggest that the CMC can be applied to in vivo study.