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 mascle 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 of the 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.

Screening of immune cell activators from Astragali Radix using a comprehensive two-dimensional NK-92MI cell membrane chromatography/C18 column/time-of-flight mass spectrometry system

Astragali Radix(AR)is a clinically used herbal medicine with multiple immunomodulatory activities that can strengthen the activity and cytotoxicity of natural killer(NK)cells.However,owing to the complexity of its composition,the specific active ingredients in AR that act on NK cells are not clear yet.Cell membrane chromatography(CMC)is mainly used to screen the active ingredients in a complex system of herbal medicines.In this study,a new comprehensive two-dimensional(2D)NK-92MI CMC/C18 column/time-of-flight mass spectrometry(TOFMS)system was established to screen for potential NK cell activators.To obtain a higher column efficiency,3-mercaptopropyltrimethoxysilane-modified silica was synthesized to prepare the NK-92MI CMC column.In total,nine components in AR were screened from this system,which could be washed out from the NK-92MI/CMC column after 10 min,and they showed good affinity for NK-92MI/CMC column.Two representative active compounds of AR,isoastragaloside Ⅰ and astragaloside IV,promoted the killing effect of NK cells on K562 cells in a dose-dependent manner.It can thus suggest that isoastragaloside Ⅰ and astragaloside Ⅳ are the main immunomodulatory components of AR.This comprehensive 2D NK-92MI CMC analytical system is a practical method for screening immune cell activators from other herbal medicines with immunomodulatory effects.

Cell membrane chromatography and its application in the analysis of bioactive ingredients of TCMs

Traditional Chinese medicines （TCMs） have a long history of clinical testing and reliable therapeutic efficacy. They have attracted international attention as excellent sources of bioactive compounds for the discovery of new drugs. However, TCMs usually contain hundreds or even thousands of components and only a few of these compounds are responsible for the pharmacological effects. The large number of components in TCMs makes the analysis and screening for bioactive compounds extremely difficult. Therefore, strategies for analysis and screening of bioactive compounds in TCMs have long been a focus of studies on TCMs. Cell membrane chromatography （CMC） has become a useful tool for studying the bioactive compounds of TCMs. This review summarizes the principles, characteristics, and application of CMC, and the possible problems faced when working with TCMs. This method will likely become increasingly important for screening and analysis of hioactive compounds in TCMs.

Development of 3-mercaptopropyltrimethoxysilane(MPTS)-modified bone marrow mononuclear cell membrane chromatography for screening anti-osteoporosis components from Scutellariae Radix

Osteoporosis is a bone metabolic disease caused by the imbalance between osteoblasts and osteoclasts due to excess osteoclastogenesis,manifesting in the decrease of bone density and bone strength.Scutellariae Radix shows good anti-osteoporosis activity,but the effective component is still unclear.Cell membrane chromatography(CMC)is a biological affinity chromatography with membrane immobilized on a silica carrier as the stationary phase.It can realize a dynamical simulation of interactions between drugs and receptors on cell membrane,which is suitable for screening active compounds from complex systems.In this study,the components of Scutellariae Radix with potential anti-osteoporosis activity through inhibiting the differentiation from bone marrow mononuclear cells(BMMCs)to osteoclast were screened by a BMMC/CMC analytical system.Firstly,a new3-mercaptopropyltrimethoxysilane(MPTS)-modified BMMC/CMC stationary phase was developed to realize covalent binding with cell membrane fractions.By investigating the retention time(tR)of the positive drug,the life span of the MPTS-modified CMC columns was significantly improved from 3 to 12 days.Secondly,6 components of Scutellariae Radix were screened to show affinity to membrane receptors on BMMCs by a two-dimensional BMMC/CMC-TOFMS analytical system.Among them,tectochrysin demonstrated the best anti-osteoporosis effect in vitro,which has never been reported.We found that tectochrysin could inhibit the differentiation of BMMCs into osteoclasts induced by receptor activator of nuclear factor-κB ligand(RANKL)and macrophage colony-stimulating factor(M-CSF)in a concentration-dependent manner in vitro.In vivo,it significantly reduced the loss of bone trabeculae in ovariectomized mice,and decreased the level of C-terminal cross-linking telopeptides of type 1 collagen(CTX-1),tartrate-resistant acid phosphatase 5 b(TRAP-5 b),interleukin 6(IL-6)in serum.In conclusion,tectochrysin serves as a potential candidate in the treatment of osteoporosis.The proposed twodimensional MPTS-modified BMMC/CMC-TOFMS analytical system shows the advantages of longlife span and fast recognition ability,which is very suitable for infrequent cell lines.

A high expression EGFR/cell membrane chromatography and online high performance liquid chromatography/mass spectrometry method for screening EGFR antagonists from Rhizoma Polygoni Cuspidati

The epidermal growth factor receptors(EGFRs)in some tumor cells are significant targets for drug discovery.In this work,we have developed an EGFR cell membrane chromatography and online high performance liquid chromatography/mass spectrometry system for screening active component from Rhizoma Polygoni Cuspidati.As a result,resveratrol from Rhizoma Polygoni Cuspidati was found to be the active component acting on EGFR like gefitinib.There was a good relationship between their inhibiting effects on EGFR secretion and HEK293 EGFR cell growth in vitro.The EGFR/CMC-online-HPLC/MS system demonstrated fast and effective characteristics for screening leading compounds from traditional Chinese medicine.

Hydrophobic interaction membrane chromatography for bioseparation and responsive polymer ligands involved

Hydrophobic interaction chromatography （HIC） is a rapid growing bioseparation technique, which separates biomolecules, such as therapeutic proteins and antibodys, based on the reversible hydrophobic interaction between immobilized hydrophobic ligands on chromatographic resin spheres and non-polar regions of solute molecule. In this review, the fundamental concepts of HIC and the factors that may affect purification efficiency of HIC is summarized, followed by the comparison of HIC with affinity chromatography and ion-exchange chromatography. Hydrophobic interaction membrane chromatography （HIMC） combines the advantages of HIC and membrane process and has showed great potential in bioseparation. For better understanding of HIMC, this review presents an overview of two main concerns about HIMC, i.e. membrane materials and hydrophobic ligands. Specifically, cellulose fiber-based membrane substrate and environment-responsive ligands are emphasized.

Interactions Mode of Amphoteric Molecules with Ordered Phospholipid Membrane

Aim To explore interaction mode between amphoteric molecules with the orderedphospholipid membrane. Methods Membrane interactions were determined by immobilized artificialmembrane (IAM) chromatography and solutes' hydrophobicity was measured by n-octanol/buffer system.Results The ampholytes, similar to bases, generally exhibited higher membrane affinity than expectedfrom their hydrophobicity, resulting from the attractive polar interaction with phospholipidmembrane. Furthermore, the strength of additional polar interaction with membrane (Δlg k_(IAM)) wasthen calculated. The Δlg k_(IAM) values were far greater for bases and ampholytes ranging from0.50 - 1.39, than those for acids and neutrals with the scope from - 0.55 - 0.44. ConclusionConsidering the microspecies distribution of amphoteric molecules, it was assumed that not onlyneutral and positive but also zwitterionic microspecies are capable of partitioning into orderedamphoteric lipid membrane with complementarily conformational and energetically favorableinteractions.

Baicalein:A potential GLP-1R agonist improves cognitive disorder of diabetes through mitophagy enhancement

There is increasing evidence that the activation of glucagon-like peptide-1 receptor(GLP-1R)can be used as a therapeutic intervention for cognitive disorders.Here,we have screened GLP-1R targeted compounds from Scutellaria baicalensis,which revealed baicalein is a potential GLP-1R small-molecule agonist.Mitophagy,a selective autophagy pathway for mitochondrial quality control,plays a neuroprotective role in multiple cognitive impairment diseases.We noticed that Glp1r knock-out(KO)mice present cognitive impairment symptoms and appear worse in spatial learning memory and learning capacity in Morris water maze(MWM)test than their wide-type(WT)counterparts.Our mechanistic studies revealed that mitophagy is impaired in hippocampus tissue of diabetic mice and Glp1r KO mice.Finally,we verified that the cognitive improvement effects of baicalein on diabetic cognitive dysfunction occur through the enhancement of mitophagy in a GLP-1R-dependent manner.Our findings shed light on the importance of GLP-1R for cognitive function maintenance,and revealed the vital significance of GLP-1R for maintaining mitochondrial homeostasis.Furthermore,we identified the therapeutic potential of baicalein in the treatment of cognitive disorder associated with diabetes.

INHIBITORY EFFECTS OF THE ALKALOIDS FROM Radix Caulophylli ON THE PROLIFERATION OF HUMAN VASCULAR ENDOTHELIAL CELL

Objective To find an angiogenetic inhibitor from Radix Caulophylli (RC). Methods The extract of Radix Caulophylli was obtained by using 95% alcohol in water as solvent. Then, the total alkaloids of Radix Caulophylli was isolated from the extract by using a positive ion exchange resin column. An active part was found by a screening model of cell membrane chromatography (CMC) and further tested by the MTT method with emodin as a control. Results The total alkaloids of Radix Caulophylli was the active part by CMC and could significantly inhibit proliferation of ECV304 cells in MTT test. The inhibitory rate was 56.06% while the concentration of the total alkaloids of Radix Caulophylli was 19.63μg/mL. Conclusion The total alkaloids from Radix Caulophylli may be a new angiogenetic inhibitor, and mechanism of the total alkaloids on inhibitory angiogenesis still need to be further investigated.

Poly(vinylidene fluoride) membrane based thin film microextraction for enrichment of benzoylurea insecticides from water samples followed by their determination with HPLC

Thin-film microextraction（TFME）,a new geometry for solid-phase microextraction,has become an attractive sample-preparation technique.Compared to other microextraction approaches,the sensitivity of this technique was enhanced without sacrificing the sampling time due to the high surface area-tovolume ratio together with the increase of extraction-phase volume.In this paper,a new TFME method based on poly（vinylidene fluoride） membrane was developed for the extraction of benzoylurea insecticides（diflubenzuron,triflumuron,hexaflumuron and teflubenzuron） from water samples followed by their determination with high performance liquid chromatography-diode array detection.Under the optimal conditions,good linearity was observed over the concentration range of 0.5-100.0 ng/mL with correlation coefficient greater than 0.9994.The limits of detection（S/N = 3） of the method for the target analytes were 0.1 ng/mL.Mean recoveries ranged from 87.7% to 103.9% with relative standard deviations lower than 6.5%.The results indicated that the developed TFME method is simple,efficient,and cost effective.