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1.
Anal Bioanal Chem ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535814

RESUMO

In this study, a magnetic yolk-shell structured metal-organic framework material (Fe3O4@YS-UiO-66-NH2) is prepared by the directional etching of Co2+/peroxymonosulfate and in situ magnetization. The characteristic properties of the material were investigated by using field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer, Brunauer-Emmett-Teller, and contact angle test. The Fe3O4@YS-UiO-66-NH2 shows the advantages of large surface area, good magnetic property, and satisfactory stability, as well as giving high affinity to alkaloids (ALs) via hydrophilic interaction, hydrogen bonding, and π-π interaction. The results of static adsorption experiment indicate that the Fe3O4@YS-UiO-66-NH2 possesses high adsorption capacity towards ALs and the adsorption behaviors are fitted with Langmuir adsorption isotherm model. Furthermore, a magnetic solid-phase extraction using Fe3O4@YS-UiO-66-NH2 and HPLC method was developed for the analysis of ALs in spiked samples with the recovery of 89.6-100.8%. In addition, the proposed method was successfully applied in the pharmacokinetics study of berberine, coptisine, and palmatine in the rat. In short, the developed method might be used for high-efficient recognition and determination of ALs in plasma sample, which would also provide a new way to fabricate magnetic functionalized metal-organic framework in separation science.

2.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361791

RESUMO

As a key enzyme regulating postprandial blood glucose, α-Glucosidase is considered to be an effective target for the treatment of diabetes mellitus. In this study, a simple, rapid, and effective method for enzyme inhibitors screening assay was established based on α-glucosidase catalyzes reactions in a personal glucose meter (PGM). α-glucosidase catalyzes the hydrolysis of maltose to produce glucose, which triggers the reduction of ferricyanide (K3[Fe(CN)6]) to ferrocyanide (K4[Fe(CN)6]) and generates the PGM detectable signals. When the α-glucosidase inhibitor (such as acarbose) is added, the yield of glucose and the readout of PGM decreased accordingly. This method can achieve the direct determination of α-glucosidase activity by the PGM as simple as the blood glucose tests. Under the optimal experimental conditions, the developed method was applied to evaluate the inhibitory activity of thirty-four small-molecule compounds and eighteen medicinal plants extracts on α-glucosidase. The results exhibit that lithospermic acid (52.5 ± 3.0%) and protocatechualdehyde (36.8 ± 2.8%) have higher inhibitory activity than that of positive control acarbose (31.5 ± 2.5%) at the same final concentration of 5.0 mM. Besides, the lemon extract has a good inhibitory effect on α-glucosidase with a percentage of inhibition of 43.3 ± 3.5%. Finally, the binding sites and modes of four active small-molecule compounds to α-glucosidase were investigated by molecular docking analysis. These results indicate that the PGM method is feasible to screening inhibitors from natural products with simple and rapid operations.


Assuntos
Benzaldeídos/farmacologia , Benzofuranos/farmacologia , Glicemia/análise , Catecóis/farmacologia , Depsídeos/farmacologia , Diabetes Mellitus Tipo 2/diagnóstico , Inibidores de Glicosídeo Hidrolases/farmacologia , Monitorização Ambulatorial/métodos , alfa-Glucosidases/sangue , Acarbose/química , Acarbose/farmacologia , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Benzofuranos/química , Benzofuranos/isolamento & purificação , Sítios de Ligação , Técnicas Biossensoriais/instrumentação , Catecóis/química , Catecóis/isolamento & purificação , Depsídeos/química , Depsídeos/isolamento & purificação , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/química , Humanos , Hidrólise , Cinética , Maltose/metabolismo , Simulação de Acoplamento Molecular , Monitorização Ambulatorial/instrumentação , Extratos Vegetais/química , Plantas Medicinais , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Termodinâmica , Dispositivos Eletrônicos Vestíveis , alfa-Glucosidases/química
3.
Molecules ; 26(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203179

RESUMO

In this study, a polydopamine (PDA)-modified hollow fiber-immobilized xanthine oxidase (XOD) was prepared for screening potential XOD inhibitors from flavonoids. Several parameters for the preparation of PDA-modified hollow fiber-immobilized XOD, including the dopamine concentration, modification time, XOD concentration and immobilization time, were optimized. The results show that the optimal conditions for immobilized XOD activity were a dopamine concentration of 2.0 mg/mL in 10.0 mM Tris-HCl buffer (pH 8.5), a modification time of 3.0 h, an XOD concentration of 1000 µg/mL in 10.0 mM phosphate buffer (pH 7.5) and an immobilization time of 3.0 h. Subsequently, the enzymatic reaction conditions such as the pH value and temperature were investigated, and the enzyme kinetics and inhibition parameters were determined. The results indicate that the optimal pH value (7.5) and temperature (37 °C) of the PDA-modified hollow fiber-immobilized XOD were consistent with the free enzyme. Moreover, the PDA-modified hollow fiber-immobilized XOD could still maintain above 50% of its initial immobilized enzyme activity after seven consecutive cycles. The Michaelis-Menten constant (Km) and the half-maximal inhibitory concentration (IC50) of allopurinol on the immobilized XOD were determined as 0.25 mM and 23.2 µM, respectively. Furthermore, the PDA-modified hollow fiber-immobilized XOD was successfully applied to evaluate the inhibitory activity of eight flavonoids. Quercetin, apigenin, puerarin and epigallocatechin showed a good inhibition effect, and their percentages of inhibition were (79.86 ± 3.50)%, (80.98 ± 0.64)%, (61.15 ± 6.26)% and (54.92 ± 0.41)%, respectively. Finally, molecular docking analysis further verified that these four active compounds could bind to the amino acid residues in the XOD active site. In summary, the PDA-modified hollow fiber-immobilized XOD is an efficient method for the primary screening of XOD inhibitors from natural products.


Assuntos
Inibidores Enzimáticos/química , Enzimas Imobilizadas , Flavonoides/química , Indóis/química , Polímeros/química , Xantina Oxidase , Enzimas Imobilizadas/antagonistas & inibidores , Enzimas Imobilizadas/química , Simulação de Acoplamento Molecular , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/química
4.
Enzyme Microb Technol ; 148: 109805, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116756

RESUMO

In this study, a paper-based sensor, combined with a visual distance-readout method, was developed to determine glucose in fruit samples based on the glucose oxidase-mediated sodium alginate gelation. The type of filter paper, the concentration of sodium alginate and the enzymatic reaction conditions were systematically investigated. Under optimal conditions, the increase in diffusion diameter showed a good linear relationship with glucose concentration between 1.4-7.0 mM, and the limit of quantification was 1.4 mM. Finally, the applicability of the proposed strategy was successfully verified by measuring glucose concentrations in fruit samples. The results generated by the developed paper-based sensor were in good agreement with the results obtained from a glucose assay kit. The recoveries were 91.8%-99.1%. In short, the present study developed a simple, low-cost and efficient method for assessing fruit quality and for guiding fruit intake for diabetic patients, especially in remote or resource-limited regions.


Assuntos
Técnicas Biossensoriais , Frutas/química , Glucose Oxidase , Alginatos , Glucose , Papel
5.
Enzyme Microb Technol ; 148: 109830, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116751

RESUMO

In this study, a paper-based sensor combined with visual distance-readout technique for point of-care testing (POCT) of urea was developed by urease-mediated chitosan viscosity change. A series of factors that affect the performance of the sensor were investigated, including the type of filter paper, chitosan concentration, acetic acid concentration and enzymatic reaction conditions. Under optimal conditions, the proposed method for urea determination has good linearity between 3.8-15.1 mM. The limit of quantitation is 3.8 mM. Finally, the paper-based sensor was successfully applied to the determination of urea in two diesel exhaust fluid (DEF) samples. The recoveries of urea were 91.4 % and 109.9 % in DEF-1 and DEF-2, respectively. The present study provides a novel approach, which integrates paper-based sensor and visual distance-readout technique, for monitoring urea in POCT application, especially in remote or resource-limited regions.


Assuntos
Técnicas Biossensoriais , Quitosana , Ureia , Urease , Viscosidade
6.
Enzyme Microb Technol ; 146: 109776, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33812564

RESUMO

A simple, convenient and efficient enzyme immobilization method through phytic acid (PA) modified α-Glucosidase (α-Glu)/Cu3(PO4)2·3H2O hybrid nanoflower was developed. The structural properties of the materials were studied by several characterization techniques. Subsequently, the enzymatic reaction conditions such as the pH value and temperature were optimized, and the enzyme kinetics and inhibition parameters were determined. The PA modified α-Glu/Cu3(PO4)2·3H2O hybrid nanoflower had better enzymatic activity under a wide pH range and high temperature than the free one. After seven successive cycles, the PA modified α-Glu/Cu3(PO4)2·3H2O hybrid nanoflower could still maintain approximately 63.0 % of its initial immobilized enzyme activity. The Michaelis-Menten constant (Km) and the half-maximal inhibitory concentration (IC50) of acarbose were determined as 0.77 mM and 15.01 µM, respectively. In addition, the material was applied to evaluate the inhibitory activity of ten phenolic compounds on α-Glu, and epicatechin gallate, gallocatechin gallate, epigallocatechin gallate and rosmarinic acid showed good inhibitory activity with % of inhibition of (53.42 ± 2.39)%, (37.28 ± 1.32)%, (37.08 ± 0.63)% and (35.53 ± 0.23)%, respectively. These results indicate that the PA modified hybrid nanoflower is an efficient method of α-Glu immobilization.


Assuntos
Glucosidases , Ácido Fítico , Enzimas Imobilizadas , Temperatura
7.
Electrophoresis ; 42(14-15): 1436-1449, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33908064

RESUMO

Profiling of lipid-water partition coefficients (KL/W ) of drugs is an essential issue during the early stage of drug development. In this study, two liposomes, including 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) + cholesterol (Chol) (DSPC/Chol liposomes) and soybean lecithin (SPC) + Chol (SPC/Chol liposomes), were prepared for the liposome electrokinetic chromatography (LEKC) analysis, and the logarithm of lipid-water partition coefficients (log KL/W ) of neutral and ionic drugs were determined based on an iterative method. The log KL/W values determined by the SPC/Chol or DSPC/Chol liposomes LEKC were linearly fitted, which showed a good fitting coefficient (R2 = 0.89). Furthermore, the linear relationship between the data obtained from LEKC system and octanol-water system, immobilized artificial membrane, Caco-2 cell model, and software prediction was analyzed, respectively. Results illustrated that DSPC/Chol liposomes or SPC/Chol liposomes had a good linear relationship with Caco-2 cell model, and R2 was 0.81 and 0.72, respectively. Moreover, the linear free energy relationship analysis suggested that the solute volume, hydrogen bond basicity, and J- were the main descriptors that drove the partition process of solutes in the SPC/Chol or DSPC/Chol LEKC system. In addition, the normalized properties of the SPC/Chol and DSPC/Chol LEKC systems through linear free energy relationship analysis were very close. In short, DSPC/Chol liposomes are more suitable for simulating cell membranes than SPC/Chol liposomes, and the developed LEKC is an effective partitioning model for measuring the log KL/W of drugs.

8.
Anal Bioanal Chem ; 413(9): 2457-2466, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33674935

RESUMO

In this study, an effective and portable method for enzyme activity detection and inhibitory activity evaluation was developed based on the alkaline phosphatase (ALP)-mediated reaction in a personal glucose meter (PGM). In this method, ALP catalyzes the hydrolysis of substrate amifostine (WR-2721) to produce ethanethiol (WR-1065), which can trigger the reduction of ferricyanide (K3[Fe(CN)6]), an electron transfer mediator in glucose test strips, to ferrocyanide ([K4Fe(CN)6]) and generate a PGM-detectable signal. Thus, WR-1065 can be directly quantified by a PGM as simply as detecting glucose in blood. After being systematically optimized, the method was applied to evaluate the inhibitory activity of ten small-molecule compounds and six Cordyceps sinensis (CS) extracts on ALP. The results showed that adenosine-5-monophosphate and theophylline had high inhibitory activity, but two CS extracts have promotion potency on ALP with the values of -20.7 ± 1.3% and -46.6 ± 2.1%, respectively. Moreover, the binding sites and modes of small-molecule compounds to ALP were investigated by molecular docking, while a new substrate competitor with theoretically good inhibitory activity against ALP was designed by scaffold hopping. Finally, the accuracy of the PGM method for enzyme activity detection was assessed by detecting ALP from milk samples, and the recovery ranged from 87.7% to 116.9%. These results indicate that it is feasible to evaluate enzyme activity and the inhibitory activity of small-molecule compounds and CS extracts on ALP using a PGM based on ALP-mediated reaction. Graphical abstract.


Assuntos
Fosfatase Alcalina/metabolismo , Técnicas Biossensoriais/métodos , Glicemia/análise , Ensaios Enzimáticos/métodos , Fosfatase Alcalina/antagonistas & inibidores , Técnicas Biossensoriais/instrumentação , Ensaios Enzimáticos/instrumentação , Inibidores Enzimáticos/farmacologia , Desenho de Equipamento , Humanos , Modelos Moleculares
9.
Phytochem Anal ; 32(2): 198-205, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32519355

RESUMO

INTRODUCTION: Emerging network pharmacology (NP) combines phytochemical information with bioinformatics tools allowing herbal formulae to be illustrated holistically in the context of phytochemical basis and therapeutic mechanisms. OBJECTIVE: This study attempted to explore the holistic molecular evidence of herbal formula Si-Wu decoction (SWD) by using the method of NP. MATERIAL AND METHOD: Databases of traditional medicines combined with PubChem, SciFinder, SEA, STRING, and KEGG were employed to gather information for establishing the "compound similarity" (CS) network and the "target-(pathway)-target" (TPT) network. Gephi software was applied to visualise the networks, with further module-based and node-based network topological analysis. Moreover, the approved drugs and shortest path analysis were used to validate the TPT network. RESULTS: The CS network presented the phytochemical profile of SWD, including the major compound groups of iridoid glycosides, glycosides, phthalide lactones, phenylpropanoids, and monoterpenoids. Furthermore, the topological analysis of TPT network depicted the holistic property of SWD in interpretable neuroendocrine immunomodulation (NIM) perspective, and the node degree analysis indicated a closer connection of SWD with endocrine or metabolism system. Moreover, by combing the analysis of the CS network and TPT network, potential active ingredients could be primarily identified. CONCLUSION: The phytochemical profile and molecular target profile, which might pave the way for an understanding of SWD in modern science and provide a reference for relevant quality research and evaluation, were demonstrated by network analysis. Moreover, the methods could be further applied to discover the phytochemical or biomolecular evidence with distinct advantages in dealing with the tremendous separated information.


Assuntos
Medicamentos de Ervas Chinesas , Compostos Fitoquímicos
10.
J Pharm Biomed Anal ; 193: 113743, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33221573

RESUMO

In this study, a method based on adsorbed hollow fiber immobilized tyrosinase (TYR) was developed to screening potential TYR inhibitors from Pueraria lobate extract. Kojic acid and ranitidine were used as positive and negative control to verify the reliability of the proposed method, respectively. Several significant parameters of the screening process, including the amount of P. lobata extract, adsorption time and incubation time, were optimized. After investigating the repeatability of the developed method, seven potential active compounds in P. lobata extract were successfully detected and their chemical structures were tentatively identified by liquid chromatography - mass spectrometry analysis. Furthermore, the inhibitory activity of four identified compounds on TYR was tested in vitro, and three of them, namely, puerarin, puerarin-6″-O-xyloside and puerarin apioside were verified to have good TYR inhibitory activity with IC50 value of 478.5, 513.8, and 877.3 µM, respectively. In addition, the molecular docking results indicated that these compounds could bind to the amino acid residues in TYR catalytic pocket. These results proved that the proposed method is a feasible approach for screening of TYR inhibitors from plant extract.


Assuntos
Isoflavonas , Pueraria , Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Extratos Vegetais/farmacologia , Reprodutibilidade dos Testes
11.
J Pharm Biomed Anal ; 192: 113675, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33099113

RESUMO

Sample preparation such as isolation and pre-concentration is a crucial step for the phytochemical analysis. Magnetic solid-phase extraction (MSPE) has received considerable attention, mainly due to its phase separation more conveniently by facile magnetic decantation as compared to traditional SPE. This review focused on the recent applications of MSPE in sample preparation for the analysis of phytochemical compounds in plants, biological samples and Chinese herbal preparations. In addition, the enzymes immobilized on the magnetic materials and used for the biospecific extraction of enzyme inhibitors were also discussed. The information summarized in this article may provide a reference to the further applications of MSPE in phytochemical analysis.


Assuntos
Magnetismo , Extração em Fase Sólida , Fenômenos Magnéticos , Compostos Fitoquímicos
12.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33381797

RESUMO

In drug discovery, one of the most important tasks is to find novel and biologically active molecules. Given that only a tip of iceberg of drugs was founded in nearly one-century's experimental exploration, it shows great significance to use in silico methods to expand chemical database and profile drug-target linkages. In this study, a web server named ChemGenerator was proposed to generate novel activates for specific targets based on users' input. The ChemGenerator relies on an autoencoder-based algorithm of Recurrent Neural Networks with Long Short-Term Memory by training of 7 million of molecular Simplified Molecular-Input Line-Entry System as the basic model, and further develops target guided generation by transfer learning. As results, ChemGenerator gains lower loss (<0.01) than existing reference model (0.2~0.4) and shows good performance in the case of Epidermal Growth Factor Receptor. Meanwhile, ChemGenerator is now freely accessible to the public by http://smiles.tcmobile.org. In proportion to endless molecular enumeration and time-consuming expensive experiments, this work demonstrates an efficient alternative way for the first virtual screening in drug discovery.

13.
J Sep Sci ; 44(6): 1220-1230, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33369071

RESUMO

In this study, a zirconium terephthalate metal-organic framework-coated magnetic nanoparticle (UiO-66@PA@PEI@Fe3 O4 ) was synthesized for the extraction of berberine prior to high-performance liquid chromatography analysis. The phytic acid, which could be grafted onto the magnetic nanoparticle through electrostatic interaction with the abundant amino groups of polyethylenimine, possesses outstanding metal ion coordination ability for the immobilization of metal-organic frameworks UiO-66. The physicochemical properties of the obtained nanoparticle were thoroughly investigated by a series of characterization techniques. Then, the factors that will affect the extraction efficiency and recovery of berberine were investigated. Results indicated that the material had good stability and reusability, and high adsorption capacity (50.01 mg/g) to berberine through single-layer adsorption. In addition, a molecular docking study indicated that the interactions between the material and berberine were mainly π-π stacking and hydrophobic interaction. Finally, the material was successfully applied to the extraction of berberine in Rhizoma Coptidis and Cortex Phellodendri extracts with the recoveries of 76.1% and 71.6%, respectively.

14.
Anal Chim Acta ; 1142: 19-27, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33280697

RESUMO

In this study, a simple and portable enzyme activity assay and inhibitor screening method was developed based on ß-Glucosidase-mediated cascade reaction in a personal glucose meter (PGM). The inhibition of castanospermine (ß-Glucosidase inhibitor) on ß-Glucosidase leads to reducing the yields of glucose and saligenin produced by the catalysis hydrolysis of D (-)-Salicin. The ferricyanide (K3 [Fe(CN)6]) can be reduced by the products of glucose and saligenin to form ferrocyanide ([K4[Fe(CN)6]) in the glucose strips, and thereby get the electron to generate PGM detectable signals. This strategy can realize the direct determination of glucose and saligenin using PGM as simple as measuring the glucose in blood. Under the optimum experimental conditions, quantitative detection of ß-Glucosidase in crude almond sample was achieved within the ranges of 1.0-9.0 U/mL with the limit of detection of 0.45 U/mL. The recoveries of ß-Glucosidase spiked with two different concentrations (3.0 and 6.0 U/mL) in the crude bitter almond extracts were determined as 96.2% and 84.3%, respectively. Furthermore, gallic acid, protocatechualdehyde, cryptochlorogenic acid, epigallocatechin, epicatechin and vanillic acid exhibited good inhibitory effect (all higher than 40%) on ß-Glucosidase. In addition, tea polyphenol extracts of raw Pu-erh and Fuding white tea had good inhibition potency and the % of inhibition were (29.0 ± 3.5)% and (21.1 ± 2.2)% on ß-Glucosidase, respectively. Finally, molecular docking study indicated that hydrogen bonding plays an important role in the interaction between the compounds and ß-Glucosidase. The enzyme activity assay and inhibitor screening method developed in present study using PGM based on ß-Glucosidase-mediated cascade reaction would be of value for expanding the application of PGM in non-glucose target analysis.


Assuntos
Glucose , beta-Glucosidase , Automonitorização da Glicemia , Hidrólise , Simulação de Acoplamento Molecular
15.
Talanta ; 219: 121350, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887078

RESUMO

In this work, efficient, sensitive bifunctional-monomer chitosan magnetic molecularly imprinted polymers (BCMMIPs) were fabricated and successfully applied to concentrate the metabolites of Epimedium flavonoids in rat testis and bone that were later analyzed using UPLC-Q-TOF-MS. Using chitosan and methacrylic acid as co-functional monomers, BCMMIPs exhibited a large adsorption capacity (7.60 mg/g), fast kinetics (60 min), and good selectivity. Chitosan is bio-compatible and non-toxic, and methacrylic acid provides multiple hydrogen bond donors. The BCMMIPs were injected into rat testis to specifically enrich the total flavonoid metabolites in vivo and were used to extract metabolites from bone in vitro. The results showed that the BCMMIPs coupled with UPLC-Q-TOF-MS successfully identified 28 compounds from testis and 18 compounds from bone, including 19 new compounds. This study provided a reliable protocol for the concentration of metabolites from complex biological samples, and several new metabolites of Epimedium flavonoids were found in vivo and in vitro.


Assuntos
Quitosana , Epimedium , Impressão Molecular , Adsorção , Animais , Glicosídeos , Fenômenos Magnéticos , Masculino , Polímeros Molecularmente Impressos , Polímeros , Ratos , Extração em Fase Sólida
16.
Talanta ; 219: 121283, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887173

RESUMO

In this report, a non-toxic Dual Template Molecularly Imprinted Polymers (DMIPs) was synthesized with quercetin and schisandrin b as template molecules, using deep-eutectic solvents as functional monomers for the first time. The DMIPs were used to efficiently and simultaneously enrich quercetin and schisandrin b from the mixed crude extracts of penthorum and schisandra. The results indicated that the DMIPs exhibited rapid adsorption kinetics (80 min for adsorption equilibrium) and high selectivity. The largest adsorbing capacities to quercetin and schisandrin b were 23.58 mg/g and 41.64 mg/g, respectively. After presaturation with quercetin and schisandrin b, the nontoxic saturated DMIPs were fed to the mice. Blood samples of the mice were taken and both quercetin and schisandrin b were successfully detected. The pharmacokinetics of quercetin and schisandrin b were similar to reports in the literature where mice were directly fed with botanicals. Our study provides a reliable protocol such that DMIPs can be used to separate and enrich several target molecules simultaneously from complex biological systems. Our findings suggested that the DMIPs have potential application as a drug delivery system of compound herbal formulas.


Assuntos
Impressão Molecular , Adsorção , Animais , Camundongos , Polímeros Molecularmente Impressos , Polímeros , Extração em Fase Sólida
17.
Chin Med ; 15: 93, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874198

RESUMO

Background: The dry root and rhizome of Ligusticum chuanxiong Hort., or Chuanxiong, has been used as a blood-activating and stasis-removing traditional Chinese medicine for 1000 years. Our previous studies have shown the inhibitory activity on platelet and thrombin (THR) of Chuanxiong. THR and factor Xa (FXa) play significant roles in the coagulation cascade and their inhibitors are of valuable in the treatment of thromboembolic diseases. The aim of the present study is to screen THR and FXa inhibitors from Chuanxiong. Methods: Four extracts [ethyl acetate (EA), butanol (BA) and remained extract (RE) from 75% ethanol extract, and water extract (WE)] of Chuanxiong were prepared, and their THR/FXa inhibitory activities were assessed in vitro. Following silica-gel column chromatography (SC), the active EA extract and BA extract was further partitioned, respectively. Their active fractions (EA-SC1 to EA-SC5; BA-SC1 to BA-SC5) were obtained and analyzed by LC-MS. After modeling by the principal component analysis (PCA) and orthogonal partial least squares discriminate analysis (OPLS-DA), the specific marker compounds were predicted and identified. Their enzyme inhibitory was assessed in vitro and interactions with THR/FXa were investigated by molecular docking analysis. Results: Chuanxiong EA extract showed strong activity against THR and BA extract was more effective in inhibiting FXa activity, and their fractions exhibited obvious difference in enzyme inhibitory activity. Furthermore, marker compounds a-h were predicted by PCA and OPLS-DA, and their chemical structures were identified. Among them, senkyunolide A, Z-ligustilide, ferulic acid and senkyunolide I (IC50 was determined as 0.77 mM) with potential THR inhibitory activity, as well as isochlorogenic acid A with FXa inhibitory activity were screened out. It was found that the four components could interact with the active site of THR, and the binding energy was lower than - 5 kcal/mol. Isochlorogenic acid A were bound to the active site of FXa, and the binding energy was - 9.39 kcal/mol. The IC50 was determined as 0.56 mM. Conclusions: THR/FXa inhibitory components in different extracts of Chuanxiong were successfully characterized by the method of enzyme inhibition activity assays with ultra performance liquid chromatography-quadrupole time of flight mass spectrometry-based multivariate statistical analysis.

18.
J Sep Sci ; 43(15): 3136-3145, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32515904

RESUMO

In this study, a capillary electrophoresis-based online immobilized enzyme microreactor was developed for evaluating the inhibitory activity of green tea catechins and tea polyphenol extracts on trypsin. The immobilized trypsin activity and other kinetic parameters were evaluated by measuring the peak area of the hydrolyzate of chromogenic substrate S-2765. The results indicated that the activity of the immobilized trypsin remained approximately 90.0% of the initial immobilized enzyme activity after 30 runs. The value of Michaelis-Menten constant (Km ) was (0.47 ± 0.08) mM, and the half-maximal inhibitory concentration (IC50 ) and inhibition constant (Ki ) of benzamidine were measured as 3.34 and 3.00 mM, respectively. Then, the inhibitory activity of four main catechins (epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate) and three tea polyphenol extracts (green tea, white tea, and black tea) on trypsin were investigated. The results showed that four catechins and three tea polyphenol extracts had potential trypsin inhibitory activity. In addition, molecular docking results illustrated that epigallocatechin gallate, epicatechin gallate, epicatechin, and epigallocatechin were all located not only in the catalytic cavity, but also in the substrate-binding pocket of trypsin. These results indicated that the developed method is an effective tool for evaluating inhibitory activity of catechins on trypsin.


Assuntos
Catequina/farmacologia , Inibidores Enzimáticos/farmacologia , Oligopeptídeos/análise , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Tripsina/metabolismo , Catequina/química , Catequina/isolamento & purificação , Eletroforese Capilar , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Enzimas Imobilizadas/antagonistas & inibidores , Enzimas Imobilizadas/metabolismo , Hidrólise , Simulação de Acoplamento Molecular , Oligopeptídeos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Polifenóis/química , Polifenóis/isolamento & purificação , Especificidade por Substrato , Chá/química
19.
Pharmacol Res ; 159: 104963, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32497719

RESUMO

Thrombotic events act as a critical factor that interferes with Cardiovascular Diseases (CVDs), and antithrombotic herbal medicine is a long-standing controversial issue. Although a dispute is involved in their clinical application, all parties unanimously agree that herbal products have been widely used in folk medicine, and their interactions with conventional drugs are of high concern. This study aims to investigate how antithrombotic herbal medicines interact with Western cardiovascular drugs on the molecular level by taking an example of the most frequently used herbal pair, Danshen-Chuanxiong (DS-CX), and to discover more scientific evidence on their potential herb-drug interactions. Network pharmacology (NP), as an analytical approach of a complex system, is used to visualize and compare target profiles of DS-CX and Western cardiovascular drugs, which can be applied to predict common herb-drug targets and to construct a solid context for discussing herb-drug interactions. These interactions are further validated by in vitro assays, while in vivo zebrafish model employed for evaluating an overall pharmacological efficacy of herbal pairs in specific combination ratios. The study finds that DS could react directly to the Western cardiovascular drug targets relevant to antithrombotic pathways (i.e., thrombin, coagulation factor Xa and cyclooxygenase-1), whereas CX could not react directly and can synergistically affect antithrombotic effects with DS in specific combination ratios. Moreover, it is indicated that DS-CX may generate wide biological functions by a complicated mechanism of "neuro-immune-metabolism/endocrine" (NIM), which can further cause multiple direct and indirect interactions with Western cardiovascular drugs. From the clinical perspective, herb-drug interactions should be given high attention, especially when multiple herbs are used simultaneously.

20.
Chin Med ; 15: 38, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351617

RESUMO

Background: The dry root and rhizome of Salvia miltiorrhiza Bunge, or Danshen, is a well-known traditional Chinese medicine with anticoagulant activity. Taking into account that thrombin (THR) and factor Xa (FXa) play crucial roles in the coagulation cascade, it is reasonable and meaningful to screening THR and/or FXa inhibitors from Danshen. Methods: Four extracts [butanol (BA), ethyl acetate (EA) and remained extract (RE) from 75% ethanol extract, and water extract (WE)] of Danshen were prepared, and their THR/FXa inhibitory activities were assessed in vitro. Then, the active EA extract was further separated by silica-gel column chromatography (SC), and its fractions (SC1-SC5) were analyzed by LC-MS. The principal component analysis (PCA) and orthogonal partial least squares discriminate analysis (OPLS-DA) were employed for predicting the specific marker compounds. The chemical structures of targeted compounds were identified by LC-MS/MS and their interactions with THR/FXa were analyzed by the molecular docking analysis. Results: Danshen EA extract showed strong activity against THR and FXa, and its fractions (SC1-SC5) exhibited obvious difference in inhibitory activity against these two enzymes. Furthermore, four marker compounds with potential THR/FXa inhibitory activity were screened by PCA and OPLS-DA, and were identified as cryptotanshinone, tanshinone I, dihydrotanshinone I and tanshinone IIA. The molecular docking study showed that all these four tanshinones can interact with some key amino acid residues of the THR/FXa active cavities, such as HIS57 and SER195, which were considered to be promising candidates targeting THR and/or FXa with low binding energy (< - 7 kcal mol-1). Conclusions: LC-MS combined with multivariate statistical analysis can effectively screen potential THR/FXa inhibitory components in Danshen.

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