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1.
Biomed Pharmacother ; 167: 115608, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37801902

RESUMO

BACKGROUND: Gelsemium elegans (Gardner & Chapm.) Benth (G. elegans) has been widely used as a traditional folk medicine in China and Southeast Asia. As the most abundant alkaloid in G. elegans, Koumine (KM) has been revealed the effect of inflammatory attenuation modulating by macrophage activation and polarization. PURPOSE: This study aimed to explore the effect of KM on modulation of microglia polarization that led to the suppression of neuroinflammation and further improved neurodegenerative behavior. METHODS: Inflammatory mediators, microglia M1 and M2 phenotype markers and Nrf2/HO-1 pathway related protein were assessed in LPS-induced BV2 cells and LPS-treated mice by RT-PCR, immunohistochemistry, immunofluorescence and Western blotting. Moreover, the learning and memory abilities of mice were evaluated by Morris water maze test, and the neuronal damage was evaluated by the Nissl staining. RESULTS: KM attenuated LPS-induced viability and morphological changes in BV2 microglial cells. Our findings showed that KM activated the Nrf2/HO-1 signaling pathway to promote phenotypic switch from M1 to M2 phenotypes. This switch suppresses the release of inflammatory mediators in LPS-induced BV2 cells. Meanwhile, KM attenuated neuroinflammation through modulating microglia polarization and subsequently reversed the behavioral alterations in LPS-induced mice model of neuroinflammation. CONCLUSIONS: KM may alleviate neuroinflammation by regulating microglia polarization with the involvement of Nrf2/HO-1 pathway, resulting of the neuroprotective effect.


Assuntos
Fator 2 Relacionado a NF-E2 , Doenças Neuroinflamatórias , Animais , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Microglia , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Mediadores da Inflamação/metabolismo
2.
Molecules ; 25(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911607

RESUMO

Src plays a crucial role in many signaling pathways and contributes to a variety of cancers. Therefore, Src has long been considered an attractive drug target in oncology. However, the development of Src inhibitors with selectivity and novelty has been challenging. In the present study, pharmacophore-based virtual screening and molecular docking were carried out to identify potential Src inhibitors. A total of 891 molecules were obtained after pharmacophore-based virtual screening, and 10 molecules with high docking scores and strong interactions were selected as potential active molecules for further study. Absorption, distribution, metabolism, elimination and toxicity (ADMET) property evaluation was used to ascertain the drug-like properties of the obtained molecules. The proposed inhibitor-protein complexes were further subjected to molecular dynamics (MD) simulations involving root-mean-square deviation and root-mean-square fluctuation to explore the binding mode stability inside active pockets. Finally, two molecules (ZINC3214460 and ZINC1380384) were obtained as potential lead compounds against Src kinase. All these analyses provide a reference for the further development of novel Src inhibitors.


Assuntos
Descoberta de Drogas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/química , Quinases da Família src/química , Sítios de Ligação , Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos , Humanos , Ligantes , Conformação Molecular , Estrutura Molecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Inibidores de Proteínas Quinases/farmacologia , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Quinases da Família src/antagonistas & inibidores
3.
Front Oncol ; 10: 616628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33425771

RESUMO

In this study, a combination of network pharmacology, bioinformatics analysis, molecular docking and transcriptomics was used to investigate the active ingredient and potential target of Gelsemium elegans in the treatment of colorectal cancer. Koumine was screened as the active component by targeting PDK1 through network pharmacology and reverse docking. RNA-Seq, enrichment analysis and validation experiment were then further employed to reveal koumine might function in inhibiting Akt/mTOR/HK2 pathway to regulate cell glycolysis and detachment of HK2 from mitochondria and VDAC-1 to activate cell apoptosis both in vitro and in vivo. In the present study, we provide a systematical approach for the identification of effective ingredient and potential target of herbal medicine. Our results have important implication for the intensive study of koumine as novel anticancer agents for colorectal cancer and could be supportive in its further structural modification.

4.
J Enzyme Inhib Med Chem ; 35(1): 235-244, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31760818

RESUMO

Cyclin-dependent kinase 2 (CDK2) is the family of Ser/Thr protein kinases that has emerged as a highly selective with low toxic cancer therapy target. A multistage virtual screening method combined by SVM, protein-ligand interaction fingerprints (PLIF) pharmacophore and docking was utilised for screening the CDK2 inhibitors. The evaluation of the validation set indicated that this method can be used to screen large chemical databases because it has a high hit-rate and enrichment factor (80.1% and 332.83 respectively). Six compounds were screened out from NCI, Enamine and Pubchem database. After molecular dynamics and binding free energy calculation, two compounds had great potential as novel CDK2 inhibitors and they also showed selective inhibition against CDK2 in the kinase activity assay.


Assuntos
Antineoplásicos/análise , Antineoplásicos/farmacologia , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/análise , Inibidores de Proteínas Quinases/farmacologia , Máquina de Vetores de Suporte , Células A549 , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
5.
Sci Rep ; 9(1): 8109, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147584

RESUMO

The flower of Trollius chinensis Bunge was widely used for the treatment of inflammation-related diseases in traditional Chinese medicine (TCM). In order to clarify the anti-inflammatory mechanism of this Chinese herbs, a comprehensive network pharmacology strategy that consists of three sequential modules (pharmacophore matching, enrichment analysis and molecular docking.) was carried out. As a result, Apoptosis signal-regulating kinase 1 (ASK1), Janus kinase 1 (JAK1), c-Jun N-terminal kinases (JNKs), transforming protein p21 (HRas) and mitogen-activated protein kinase 14 (p38α) that related to the anti-inflammatory effect were filtered out. In further molecular dynamics (MD) simulation, the conformation of CID21578038 and CID20055288 were found stable in the protein ASK1 and JNKs respectively. The current investigation revealed that two effective compounds in the flower of Trollius chinensis Bunge played a crucial role in the process of inflammation by targeting ASK1 and JNKs, the comprehensive strategy can serve as a universal method to guide in illuminating the mechanism of the prescription of traditional Chinese medicine by identifying the pathways or targets.


Assuntos
Flores/química , Regulação da Expressão Gênica/genética , Inflamação/tratamento farmacológico , Ranunculaceae/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Biologia Computacional , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Flores/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/genética , Inflamação/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Janus Quinase 1/genética , MAP Quinase Quinase Quinase 5/genética , Proteína Quinase 14 Ativada por Mitógeno/genética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ranunculaceae/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
6.
J Sep Sci ; 42(9): 1725-1732, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30839168

RESUMO

Leonurus japonicus houtt, a well-known herb of traditional Chinese medicine, is widely used to treat gynaecological diseases. In this study, a rapid and sensitive liquid chromatography with tandem mass spectrometry method for simultaneously quantifying leonurine and stachydrine, the two main bioactive components in Leonurus japonicus houtt, was developed and validated. Plasma samples were prepared by protein precipitation with acetonitrile and separation by a Hewlett Packard XDB-C8 column (150 × 4.6 mm, id, 5 µm) equipped with a gradient elution system containing methanol-water and 0.1% formic acid at a flow-rate of 0.4 mL/min. Components were then detected by a mass spectrometer in positive electrospray ionization mode. This method showed good linearity, precision, accuracy, recovery, stability, and negligible matrix effects, which were within acceptable ranges. The method was successfully applied to compare the pharmacokinetics in normal rats and rats with cold-stagnation and blood-stasis primary dysmenorrhoea treated with Leonurus japonicus houtt electuary. The result showed significant differences (p < 0.05) in the pharmacokinetic parameters between the primary dysmenorrhoea and normal groups. This result implied that Leonurus japonicus houtt electuary remained longer and was absorbed slower in rats with primary dysmenorrhoea and exhibited higher bioavailability and peak concentration.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Dismenorreia/tratamento farmacológico , Ácido Gálico/análogos & derivados , Leonurus/química , Prolina/análogos & derivados , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Dismenorreia/sangue , Feminino , Ácido Gálico/administração & dosagem , Ácido Gálico/farmacocinética , Humanos , Prolina/administração & dosagem , Prolina/farmacocinética , Ratos , Ratos Sprague-Dawley
7.
Molecules ; 23(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997360

RESUMO

Gelsemium elegans Benth. (G. elegans), which is a famous Chinese folk medicine, has been commonly used to treat certain types of skin ulcers and alleviate inflammation, headaches, and cancer pain. However, the extensive clinical use of G. elegans has been greatly hampered by its toxicity. As one of the most widely used herbal medicines, Glycyrrhiza uralensis Fisch, has a unique effect on detoxification of G. elegans. In the present study, a rapid and sensitive method using ultra-liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was established and validated for determination of koumine, the most abundant molecule among the alkaloids of G. elegans, in rat plasma, tissue, and liver microsome. The developed method was successfully applied to the pharmacokinetics, tissue distribution, and in vitro metabolism study in rat with or without pre-treated Glycyrrhiza uralensis Fisch extract. Meanwhile, the expression level of CYP3A1 mRNA was analyzed to explain the detoxification mechanism of Glycyrrhiza uralensis Fisch on G. elegans. As a result, our work demonstrated that Glycyrrhiza uralensis Fisch could significantly affect the pharmacokinetics and tissue distribution of koumine in rats. The detoxification mechanism of Glycyrrhiza uralensis Fisch on G. elegans may be its cytochrome enzyme up-regulation effect.


Assuntos
Gelsemium/química , Glycyrrhiza uralensis/química , Alcaloides Indólicos/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Regulação Enzimológica da Expressão Gênica , Inativação Metabólica/efeitos dos fármacos , Alcaloides Indólicos/sangue , Alcaloides Indólicos/metabolismo , Limite de Detecção , Masculino , Microssomos Hepáticos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo , Distribuição Tecidual
8.
Biomed Chromatogr ; 32(6): e4201, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29388221

RESUMO

A simple, rapid and sensitive method using UPLC-MS/MS was established and validated for simultaneous determination of gelsemine and koumine in rat plasma after oral administration of Gelsemium elegans Benth extract. Plasma was performed with methanol precipitation and berberine was chosen as the internal standard. Plasma samples were separated on an Acquity UPLC® BEH C18 column (3.0 × 50 mm, 1.7 µm) with gradient elution using acetonitrile and 0.1% formic acid aqueous solution as the mobile phase at a flow rate of 0.4 mL/min. Multiple reaction monitoring mode in positive ion mode was utilized for detection. The calibration curves were linear over the range of 0.2-100 ng/mL for gelsemine and 0.1-50 ng/mL for koumine, with the lower limits of quantification 0.2 and 0.1 ng/mL, respectively. The intra- and inter-precision and accuracy were well within the acceptable ranges. The developed method was successfully applied to an in vivo pharmacokinetic study in rat after oral administration of 10 mg/kg Gelsemium elegans Benth extract.


Assuntos
Alcaloides/sangue , Cromatografia Líquida de Alta Pressão/métodos , Gelsemium/química , Alcaloides Indólicos/sangue , Extratos Vegetais/administração & dosagem , Espectrometria de Massas em Tandem/métodos , Administração Oral , Alcaloides/química , Alcaloides/farmacocinética , Animais , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacocinética , Modelos Lineares , Masculino , Extratos Vegetais/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Biomed Chromatogr ; 32(4)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29148582

RESUMO

Orientin showed a broad array of biological activities, and it is the major bioactive compound in the Trollius chinensis Bunge. The aim of this study was to investigate the comparative pharmacokinetics of orientin after intravenous administration of single orientin and T. chinensis Bunge extract. Sample preparation involved a simple one-step deproteinization procedure with acetonitrile. Chromatographic separation was achieved on a Waters BEH C18 column with a mobile phase consisting of acetonitrile and water containing 0.1% formic acid in an isocratic elution way. The detection was accomplished in multiple reaction monitoring mode with positive electrospray ionization. The pharmacokinetic properties of orientin were compared after intravenous administrations of pure orientin and T. chinensis Bunge extract to rats with approximately the same dosage of 10 mg/kg. The results of the study indicate that the pharmacokinetics of orientin in rat plasma show significant differences between two groups. This is useful for the clinical uses of therapeutic dosing of orientin and T. chinensis Bunge.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/administração & dosagem , Flavonoides/farmacocinética , Glucosídeos/administração & dosagem , Glucosídeos/farmacocinética , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacocinética , Espectrometria de Massas em Tandem/métodos , Administração Intravenosa , Animais , Feminino , Flavonoides/sangue , Flavonoides/química , Glucosídeos/sangue , Glucosídeos/química , Modelos Lineares , Masculino , Extratos Vegetais/sangue , Extratos Vegetais/química , Ranunculaceae , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Bioorg Med Chem Lett ; 27(4): 729-732, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28131711

RESUMO

A series of (1H-1,2,3-triazol-4-yl)methoxybenzaldehyde derivatives containing an anthraquinone moiety were synthesized and identified as novel xanthine oxidase inhibitors. Among them, the most promising compounds 1h and 1k were obtained with IC50 values of 0.6µM and 0.8µM, respectively, which were more than 10-fold potent compared with allopurinol. The Lineweaver-Burk plot revealed that compound 1h acted as a mixed-type xanthine oxidase inhibitor. SAR analysis showed that the benzaldehyde moiety played a more important role than the anthraquinone moiety for inhibition potency. The basis of significant inhibition of xanthine oxidase by 1h was rationalized by molecular modeling studies.


Assuntos
Antraquinonas/química , Benzaldeídos/química , Inibidores Enzimáticos/química , Xantina Oxidase/antagonistas & inibidores , Benzaldeídos/síntese química , Benzaldeídos/metabolismo , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Concentração Inibidora 50 , Cinética , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Triazóis/química , Xantina Oxidase/metabolismo
11.
Nat Prod Res ; 31(17): 1995-2000, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28049349

RESUMO

The present study was designed to investigate the chemical constituents and bioactivities of the roots of Eleutherococcus sessiliflorus (E. sessiliflorus). The compounds were isolated through various chromatography techniques and elucidated by mass spectrometric (MS), 1D- and 2D-NMR analyses. The sedative-hypnotic effect of E. sessiliflorus ethanol extract and its fractions (acetic ether, n-butanol and water fraction) were also investigated. In the chemical constituent study, one new compound, 3-ethyl-5-hydroxy-3-(hydroxymethyl) pentyl-3-(3,4-dihydroxyphenyl) acrylate and fourteen known compounds were isolated and identified. The chromatographic fingerprint of E. sessiliflorus was established by UPLC-PDA-MS/MS analysis. In bioactivity study, it was found that the water fraction of E. sessiliflorus extract could prolong pentobarbital-induced sleeping time more than that of the other fractions of E. sessiliflorus extract in mice, which provided a basis for future study on sedative-hypnotic effect of the chemical constituents in E. sessiliflorus.


Assuntos
Eleutherococcus/química , Hipnóticos e Sedativos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , 1-Butanol/química , Animais , Etanol , Hipnóticos e Sedativos/química , Masculino , Camundongos , Pentobarbital/farmacologia , Extratos Vegetais/análise , Raízes de Plantas/química , Sono/efeitos dos fármacos , Espectrometria de Massas em Tandem
12.
PLoS One ; 9(3): e90416, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24618672

RESUMO

A metabonomic approach based on ultra performance liquid chromatography coupled with mass spectrometry (UPLC/MS) was used to study the hepatotoxicity of ricinine in rats. Potential biomarkers of ricinine toxicity and toxicological mechanism were analyzed by serum metabonomic method. The significant differences in the metabolic profiling of the control and treated rats were clear by using the principal components analysis (PCA) of the chromatographic data. Significant changes of metabolite biomarkers like phenylalanine, tryptophan, cholic acid, LPC and PC were detected in the serum. These biochemical changes were related to the metabolic disorders in amino acids and phospholipids. This research indicates that UPLC/MS-based metabonomic analysis of serum samples can be used to predict the hepatotoxicity and further understand the toxicological mechanism induced by ricinine. This work shows that metabonomics method is a valuable tool in drug mechanism study.


Assuntos
Alcaloides/farmacologia , Metaboloma/efeitos dos fármacos , Metabolômica , Piridonas/farmacologia , Alcaloides/administração & dosagem , Alcaloides/química , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Análise Química do Sangue , Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Espectrometria de Massas , Metabolômica/métodos , Ressonância Magnética Nuclear Biomolecular , Piridonas/administração & dosagem , Piridonas/química , Ratos
13.
Nat Prod Res ; 26(6): 530-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21756194

RESUMO

The present study was to investigate the pharmacokinetics of luteolin-7-O-ß-D-glucoside (LGL) and apigenin-7-O-ß-D-glucoside (AGL) in rat plasma after intravenous administration of the Humulus scandens extract (HSE). A simple and accurate high-performance liquid chromatographic (HPLC) method was successfully developed for simultaneous determination of LGL and AGL in rat plasma after the plasma protein was precipitated with methanol. HPLC analysis was performed on a C18 column with UV detection at 350 nm and a mobile phase of methanol-0.2% phosphoric acid (1 : 1, v/v). Calibration curves of LGL and AGL were linear over the concentration range of 0.16-20.0 and 0.06-7.20 µg mL⁻¹, respectively. The accuracy and precision of the two analytes at low, medium and high concentrations were within the range of -3.4% to 8.1%. The relative standard deviations (RSDs) of the intra- and inter-day precisions were less than 11.7% and 10.0%, respectively. The extraction recoveries (n = 5) varied from 91.9% to 104.1% for LGL and from 92.6% to 109.3% for AGL. The method was fully validated and successfully applied to a pharmacokinetic study of LGL and AGL in rat plasma after the intravenous administration of HSE.


Assuntos
Apigenina/sangue , Flavonas/sangue , Glucosídeos/sangue , Humulus/química , Extratos Vegetais/farmacocinética , Animais , Calibragem , Cromatografia Líquida de Alta Pressão , Injeções Intravenosas , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
14.
J Chromatogr Sci ; 43(8): 426-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16212784

RESUMO

A simple and sensitive high-performance liquid chromatographic (HPLC) method is developed for the determination of osthole in rat plasma and applied to a pharmacokinetic study in rats after administration of Fructus Cnidii extract. After addition of fluocinonide as an internal standard, plasma samples are extracted with diethyl ether. HPLC analysis of the extracts is performed on a Hypersil ODS2 analytical column, using methanol-0.4% acetic acid (65:35, v/v) as the mobile phase. The UV detector is set at 322 nm. The standard curve is linear over the range 0.0520-5.20 microg/mL (r = 0.9979). The mean extraction recoveries of osthole at three concentrations were 81.0%, 91.2%, and 90.7%, respectively. The intra- and interday precisions have relative standard deviations from 1.9% to 4.9%. The limit of quantitation is 0.0520 microg/mL. The HPLC method developed can easily be applied to the determination and pharmacokinetic study of osthole in rat plasma after the animals are given the Fructus Cnidii extract. The plasma concentration of osthole from six rats showed a Cmax of 0.776 +/- 0.069 microg/mL at Tmax of 1.0 +/- 0.3 h.


Assuntos
Apiaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/farmacocinética , Extratos Vegetais/farmacocinética , Administração Oral , Animais , Cumarínicos/administração & dosagem , Cumarínicos/sangue , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Zhongguo Zhong Yao Za Zhi ; 30(8): 586-8, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16011280

RESUMO

OBJECTIVE: To investigate the chemical constituents of Epimedium brevicornum. METHOD: The chemical constituents were isolated by using silica gel column chromatography and preparative TLC. The structures were identified on the basis of physical-chemical constants and spectral data. RESULT: Five compounds were isolated and identified as hyperoside, icariin, epimedin B, epimedin C, inositol. CONCLUSION: Compound I and III - V were isolated from the plant for the first time.


Assuntos
Epimedium/química , Flavonoides/isolamento & purificação , Plantas Medicinais/química , Quercetina/análogos & derivados , Flavonoides/química , Componentes Aéreos da Planta/química , Quercetina/química , Quercetina/isolamento & purificação
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