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1.
Bioorg Chem ; 150: 107527, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38876005

RESUMO

Two protoberberine alkaloids with a unique C28 skeleton, named xanthiumines A (1) and B (2), respectively, were isolated from the fruits of Xanthium sibiricum Patr. Their structures including absolute configurations were unequivocally established by the comprehensive NMR and MS spectroscopic data analysis together with gauge-independent atomic orbital (GIAO) NMR calculations, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of natural protoberberine alkaloid with a phenolic acid group at C-13a. Their plausible biosynthetic pathway was proposed on the basis of the coexisting alkaloid monomer as the precursor. Furthermore, the effects and related molecular mechanism of compound 1 on hepatic lipid accumulation were also investigated in oleic acid (OA)-treated HepG2 cells.


Assuntos
Proteínas Quinases Ativadas por AMP , Alcaloides de Berberina , Frutas , Xanthium , Humanos , Frutas/química , Xanthium/química , Alcaloides de Berberina/química , Alcaloides de Berberina/farmacologia , Alcaloides de Berberina/isolamento & purificação , Células Hep G2 , Estrutura Molecular , Proteínas Quinases Ativadas por AMP/metabolismo , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Descoberta de Drogas , Ativadores de Enzimas/farmacologia , Ativadores de Enzimas/química , Ativadores de Enzimas/isolamento & purificação
2.
Nat Prod Res ; : 1-12, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462768

RESUMO

Two undescribed alkaloids, 15-carboxydihydroerysotrine (1) and (14 R)-4-methoxy-13,14-dihydrooxypalmatine (2), along with six known compounds, 1,6-didehydro-3,15,16-trimethoxy-9-methylerythrinanium (3), 8-oxytetrahydropalmatine (4), 20-hydroxyecdysone (5), makisterone A (6) turkesterone (7) and magnoflorine (8) were isolated from the root part of Cocculus hirsutus (L.) W. Theob. Their structures were established based on detailed analysis of NMR, UV-Vis, HRESIMS, and single-crystal XRD spectroscopic experiments. Compounds 3, 4 and 7 were reported for the first time from the genus Cocculus. All the compounds were analysed in silico to investigate their human acetylcholinesterase inhibition potential. This analysis revealed that compounds 1 and 8 interacted well with the selected protein, which suggested their further exploration as acetylcholinesterase inhibitors via in vitro and in vivo investigation.

3.
Phytomedicine ; 126: 155444, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367423

RESUMO

BACKGROUND: Stomach diseases have become global health concerns. Protoberberine alkaloids (PBAs) are a group of quaternary isoquinoline alkaloids from abundant natural sources and have been shown to improve gastric disorders in preclinical and clinical studies. The finding that PBAs exhibit low oral bioavailability but potent pharmacological activity has attracted great interest. PURPOSE: This review aims to provide a systematic review of the molecular mechanisms of PBAs in the treatment of gastric disorders and to discuss the current understanding of the pharmacokinetics and toxicity of PBAs. METHODS: The articles related to PBAs were collected from the Web of Science, Pubmed, and China National Knowledge Infrastructure databases using relevant keywords. The collected articles were screened and categorized according to their research content to focus on the gastroprotective effects, pharmacokinetics, and toxicity of PBAs. RESULTS: Based on the results of preclinical studies, PBAs have demonstrated therapeutic effects on chronic atrophic gastritis and gastric cancer by activating interleukin-4 (IL-4)/signal transducer and activator of transcription 6 (STAT6) pathway and suppressing transforming growth factor-beta 1 (TGF-ß1)/phosphoinositide 3-kinase (PI3K), Janus kinase-2 (JAK2)/signal transducers and activators of transcription 3 (STAT3), and mitogen-activated protein kinase (MAPK) pathways. The major PBAs exhibit similar pharmacokinetic properties, including rapid absorption, slow elimination, and low bioavailability. Notably, the natural organ-targeting property of PBAs may account for the finding of their low blood levels and high pharmacological activity. PBAs interact with other compounds, including conventional drugs and natural products, by modulation of metabolic enzymes and transporters. The potential tissue toxicity of PBAs should be emphasized due to their high tissue accumulation. CONCLUSION: This review highlights the gastroprotective effects, pharmacokinetics, and toxicity of PBAs and will contribute to the evaluation of drug properties and clinical translational studies of PBAs, accelerating their transfer from the laboratory to the bedside.


Assuntos
Alcaloides de Berberina , Alcaloides de Berberina/farmacologia , Alcaloides de Berberina/farmacocinética , Humanos , Animais , Neoplasias Gástricas/tratamento farmacológico , Gastrite Atrófica/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos
4.
Fitoterapia ; 171: 105697, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37797794

RESUMO

Two previously undescribed isoquinoline alkaloids, bracteatinine (1) and isogroenlandicine (2), together with four known alkaloids - coptisine (3), dehydrocorydaline (4), palmatine (5) and jatrorrhizine (6) were isolated from the aerial parts of Corydalis bracteata (Steph. Ex. Willd.) Pers. The structures of the compounds were elucidated using 1D and 2D NMR data along with HRESI-MS. The isolated new compounds bracteatinine and isogroenlandicine are close structural derivatives and isomers of corgoine and groenlandicine, respectively. Bracteatinine is also notable, being a representative of the rare 2-benzylisoquinoline alkaloids. Many natural products isolated from different plants are used as adjuvants, in addition to standard chemotherapy, in treatment of different cancers. Cancer-associated thrombosis remains a common complication and leading cause of mortality for cancer patients. Because platelets play the key role in thrombotic complications, we investigated effects of the isolated alkaloids 1-6 on platelet reactivity and showed that they did not significantly affect platelet function.


Assuntos
Alcaloides , Corydalis , Neoplasias , Humanos , Corydalis/química , Estrutura Molecular , Alcaloides/farmacologia , Alcaloides/química , Isoquinolinas/farmacologia , Isoquinolinas/química
5.
Chem Biodivers ; 20(6): e202300570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37194166

RESUMO

Twenty-two quaternary 8-dichloromethylprotoberberine alkaloids were synthesized from unmodified quaternary protoberberine alkaloids (QPAs) to improve their physical and chemical properties and to obtain selectively anticancer derivatives. The synthesized derivatives showed more appropriate octanol/water partition coefficients by up to values 3-4 compared to unmodified QPA substrates. In addition, these compounds exhibited significant antiproliferative activity against colorectal cancer cells and lower toxicity on normal cells, resulting in more significant selectivity indices than unmodified QPA compounds in vitro. The IC50 values of antiproliferative activity of quaternary 8-dichloromethyl-pseudoberberine 4-chlorobenzenesulfonate and quaternary 8-dichloromethyl-pseudopalmatine methanesulfonate against colorectal cancer cells are 0.31 µM and 0.41 µM, respectively, significantly stronger than those of other compounds and positive control 5-fluorouracil. These findings suggest that 8-dichloromethylation can be used as one of the modification strategies to guide the structural modification and subsequent investigation of anticancer drugs for CRC based on QPAs.


Assuntos
Alcaloides , Antineoplásicos , Neoplasias Colorretais , Humanos , Alcaloides/farmacologia , Alcaloides/química , Linhagem Celular , Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Estrutura Molecular
6.
Front Genet ; 14: 1151645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035743

RESUMO

Coptis chinensis Franch. (Huanglian in Chinese) is an important economic crop with medicinal value. Its rhizome has been used as a traditional herbal medicine for thousands of years in Asia. Protoberberine alkaloids, as the main bioactive component of Coptis chinensis, have a series of pharmacological activities. However, the protoberberine alkaloids content of C. chinensis is relatively low. Understanding the molecular mechanisms affecting the transcriptional regulation of protoberberine alkaloids would be crucial to increase their production via metabolic engineering. WRKY, one of the largest plant-specific gene families, regulates plant defense responses via the biosynthesis of specialized metabolites such as alkaloids. Totally, 41 WRKY transcription factors (TFs) related to protoberberine alkaloid biosynthesis were identified in the C. chinensis genome and classified into three groups based on phylogenetic and conserved motif analyses. Three WRKY genes (CcWRKY7, CcWRKY29, and CcWRKY32) may regulate protoberberine alkaloid biosynthesis, as suggested by gene-specific expression patterns, metabolic pathways, phylogenetic, and dual-luciferase analysis. Furthermore, the CcWRKY7, CcWRKY29, and CcWRKY32 proteins were specifically detected in the nucleus via subcellular localization. This study provides a basis for understanding the regulatory mechanisms of protoberberine alkaloid biosynthesis and valuable information for breeding C. chinensis varieties.

7.
Chem Biodivers ; 20(5): e202300230, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36951446

RESUMO

Natural QPAs have anti-cancer property. The prodrugs of QPAs synthesized in our work with significantly improved solubility showed significantly stronger activity in animal experiments. Nevertheless, the mechanism of action of QPAs for treating cancers remains poorly understood. Here, a chemoproteomic study reveals that QPAs non-covalently and multivalently bind to PES1 in CRC cells, which impinges on the direct interaction between hTERT and hTR in the assembly of the telomerase complex, downregulates telomerase activity, and so promotes the aging process of CRC cells. This study is beneficial for us to conduct extensively the pharmaceutical chemistry research of QPAs.


Assuntos
Alcaloides de Berberina , Telomerase , Animais , Telomerase/metabolismo , RNA/química
8.
J Sep Sci ; 46(2): e2200613, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36446729

RESUMO

A novel magnetic sulfonated covalent organic polymer was prepared for magnetic solid-phase extraction of protoberberine alkaloids. The magnetic sulfonated covalent organic polymer was rapidly synthesized under mild conditions. The physicochemical properties of the prepared materials were characterized by Fourier-transform infrared spectrometry, transmission electron microscopy, and X-ray photoelectron spectroscopy. Several extraction parameters were systematically investigated, including desorption time, pH of sample solution, acetonitrile content, acetic acid content in the eluent, extraction time, and sample volume. By coupling magnetic solid-phase extraction and high-performance liquid chromatography, an efficient and sensitive method for the extraction and determination of protoberberine alkaloids in complex samples was developed. The proposed method showed great linearity (r > 0.9989), low limits of detection (0.2-0.3 ng/ml), and high precision (relative standard deviations ≤ 5.74%). The proposed method was further applied to the analysis of protoberberine alkaloids in Cortex phellodendri and human plasma samples. The recoveries were 91.50%-110.31% with relative standard deviations less than 6.63% in Cortex phellodendri and 96.12%-111.20% with relative standard deviations lower than 5.56% in plasma samples.


Assuntos
Alcaloides , Polímeros , Humanos , Polímeros/química , Adsorção , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção
9.
J Ethnopharmacol ; 301: 115807, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36223842

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Malaria remains one of the most important pathogenic infectious diseases. Although Africa suffers the greatest brunt, a sizeable proportion of her population still relies on herbal medicines for reasons of cost as well as the belief etched in the minds of consumers that herbal medicines are safer and more efficacious than Modern medicines. Agbo-iba; a concoction of two or more than two plants is commonly used for the management of malaria in Nigeria. AIM OF THE STUDY: This study assessed the safety and efficacy of a hepta-herbal Agbo-iba (HHA) antimalarial decoction used for the management of malaria in Benin city, Nigeria. MATERIALS AND METHODS: Assessment was done against malaria parasite in culture as well as in vivo in pre-clinical murine model of malaria. RESULTS: HHA (IC50Pf3D7 50 µg/ml) was moderately potent and only one of its constituent plants Annickia affinis (IC50Pf3D7 1.49 µg/ml) was far more potent, while all others were moderately active to inactive against the parasite in vitro. HHA showed good selectivity in vitro and was safe at 2 g/kg in mice. However, at 100 mg/kg oral dose, while HHA suppressed parasite growth by 56.76%, the suppression caused by A.affinis was only 32.46% in mice malaria suggesting the existence of synergistic partner(s) in the herbal formula. LCMS revealed the presence of quaternary protoberberine alkaloids (QPAs) in A.affinis and HHA. CONCLUSIONS: Although QPAs have strong in vitro antiplasmodial activity, their in vivo antimalarial activity is undermined by being substrates of Permeability glycoprotein (Pgp) efflux pump. Our study suggests that inhibitor(s) of Pgp in HHA could improve the bioavailability of QPAs in mice fed the herbal combo. Further, molecules from other HHA constituent plants may also contribute to the better potency observed for the polyherbal in vivo. These possibilities were validated by the curative antimalarial study at 100 mg/kg, where A.affinis was inactive but the HHA suppressed parasite growth by 44.45%.


Assuntos
Antimaláricos , Malária , Plantas Medicinais , Feminino , Camundongos , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antimaláricos/química , Nigéria , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Malária/tratamento farmacológico , Malária/parasitologia , Plantas Medicinais/química , Plasmodium falciparum , Plasmodium berghei
10.
J Chromatogr A ; 1681: 463426, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36063777

RESUMO

Quantitation of protoberberine alkaloids is an essential guarantee for efficacy control and medication safety of Coptidis Rhizoma (CR) related medicines. Traditional univariate chromatography faced challenges with co-elution, unknown interferences, and retention time shift when analyzing isomeric analytes in varying sample matrices. We presented a chemometrics-enhanced high-performance liquid chromatography-diode array detection (HPLC-DAD) strategy for simultaneous quantification of six protoberberine alkaloids and processed multi-channels chromatographic-spectral data with four second-order calibration algorithms. Chromatographic conditions were firstly optimized. Four groups of predicted samples were modeled individually with the designed calibration set. Mathematical resolutions were then obtained, and pseudo-univariate regression gave the quantitative concentration of each analyte. Four models were scored on fit, linearity, recovery, and robustness, where alternating trilinear decomposition assisted multivariate curve resolution (ATLD-MCR) exhibited an optimal and stable performance. Besides, the resolved spectra presented high consistency with the actual spectra (r≥0.9993). Limits of quantification (LOQ) fully met the pharmacopoeia stipulation and were 0.17, 0.60, 0.19, 0.74, 0.15, and 0.38 µg mL-1 for columbamine, epiberberine, jatrorrhizine, coptisine, palmatine, and berberine, respectively. The importance of this strategy is to exploit collinearity resolution and additional selectivity that permit accurate quantitation at poor chromatographic resolutions, avoiding individual pretreatment and HPLC optimizations for different samples. This study provides a universal alternative for routine quality assessment of protoberberine alkaloids in CR-related medicines.


Assuntos
Alcaloides , Alcaloides de Berberina , Berberina , Coptis , Medicamentos de Ervas Chinesas , Alcaloides/química , Berberina/análise , Alcaloides de Berberina/química , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Coptis/química , Medicamentos de Ervas Chinesas/química
11.
Bioorg Chem ; 97: 103648, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32065882

RESUMO

Natural protoberberine alkaloids were first identified and characterized as potent, selective and cellular active lysine specific demethylase 1 (LSD1) inhibitors. Due to our study, isoquinoline-based tetracyclic scaffold was identified as the key structural element for their anti-LSD1 activity, subtle changes of substituents attached to the core structure led to dramatic changes of the activity. Among these protoberberine alkaloids, epiberberine potently inhibited LSD1 (IC50 = 0.14 ± 0.01 µM) and was highly selective to LSD1 over MAO-A/B. Furthermore, epiberberine could induce the expression of CD86, CD11b and CD14 in THP-1 and HL-60 cells, confirming its cellular activity of inducing acute myeloid leukemia (AML) cells differentiation. Moreover, epiberberine prolonged the survival of THP-1 cells bearing mice and inhibited the growth of AML cells in vivo without obvious global toxicity. These findings give the potential application of epiberberine in AML treatment, and the isoquinoline-based tetracyclic scaffold could be used for further development of LSD1 inhibitors.


Assuntos
Antineoplásicos/uso terapêutico , Alcaloides de Berberina/uso terapêutico , Histona Desmetilases/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Antineoplásicos/química , Alcaloides de Berberina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HL-60 , Histona Desmetilases/metabolismo , Humanos , Camundongos , Camundongos SCID
12.
Phytomedicine ; 64: 152919, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465980

RESUMO

BACKGROUND: It has been shown that secondary metabolites occur in Chelidonium majus L. (C. majus) crude extract and milky sap (alkaloids such as berberine, coptisine, chelidonine, chelerythrine, sanguinarine, and protopine) are biologically active compounds with a wide spectrum of pharmacological functions. Berberine, an isoquinoline alkaloid extracted from plants, possesses a wide range of biological activities, including inhibition of growth of a variety of cancer cell lines. PURPOSE AND STUDY DESIGN: In the present study, we investigated the potential anticancer effect of a protoberberine alkaloidal fraction (BBR-F) isolated from the medicinal plant C. majus on HeLa and C33A cervical cancer cells after light irradiation (PDT treatment). METHODS: BBR-F was prepared from an ethanolic extract of stems of C. majus. Identification of alkaloidal compounds was performed using high-performance liquid chromatography - mass spectrometry (HPLC/ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy. BBR-F was then biologically evaluated for its anticancer properties. Cytotoxic activity after PDT treatment and without light irradiation (dark cytotoxicity) was determined by colorimetric WST-1 assay. The impact of the protoberberine alkaloidal fraction on the morphology and function of the cells was assessed by fluorescence and confocal microscopy as well as by flow cytometric analysis. To investigate the proinflammatory effect of the extracted natural BBR-F, nitric oxide concentration was determined using the Griess method. RESULTS: An effective reduction in HeLa and C33A cell viability was observed after PDT treatment of BBR-F treated cells. Furthermore, microscopic analysis identified various morphological changes in the studied cells that occurred during apoptosis. Apoptosis of HeLa and C33A cells was also characterized by biochemical changes in cell membrane composition, activation of intracellular caspases, disruption of the mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) generation. CONCLUSION: Our results strongly suggest that the components of the natural plant protoberberine fraction (BBR-F) extracted from C. majus may represent promising novel photosensitive agents and can be applied in cancer photodynamic therapy as natural photosensitizers.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Alcaloides de Berberina/farmacologia , Chelidonium/química , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides de Berberina/química , Alcaloides de Berberina/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Caules de Planta/química , Plantas Medicinais
13.
J Comput Aided Mol Des ; 32(9): 917-928, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30171419

RESUMO

The protein lysine methyltransferase G9a, which controls gene expression by epigenetic regulation of H3K9 methylation, is related to various human diseases, including cancer, drug addiction, and mental retardation. In recent years, genetic, biological, and physiological evidence has established G9a inhibitors as potential chemotherapeutic agents for cancer treatment. In this study, we identified protoberberine alkaloid pseudodehydrocorydaline (CT13) as a novel G9a inhibitor, by structure-based virtual screening of in-house library containing natural product compounds. The activity of CT13 was determined by biophysical analyses involving MALDI-TOF mass spectrometry and western blot analysis. CT13 showed selective inhibitory activity against G9a and suppressed the level of H3K9me2 in MCF7 human breast cancer cells. Molecular docking analysis suggested the binding mode of CT13 which occupies the binding site of histone H3 substrate. CT13 provides a novel scaffold for further development of analogous synthetic G9a inhibitors.


Assuntos
Alcaloides de Berberina/química , Histona Metiltransferases/antagonistas & inibidores , Alcaloides de Berberina/farmacologia , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Histonas/química , Humanos , Células MCF-7 , Metilação , Simulação de Acoplamento Molecular , Ligação Proteica , Bibliotecas de Moléculas Pequenas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Relação Estrutura-Atividade
14.
J Sep Sci ; 41(18): 3614-3621, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30035355

RESUMO

A sodium dodecyl sulfate sensitized switchable solvent liquid-phase microextraction method was developed and applied to the preconcentration of active alkaloids in Rhizoma coptidis followed by high performance liquid chromatography determination. Before extraction, nonionic triethylamine was converted to its cationic form in the presence of carbon dioxide. Then, the ionic solvent carrying target analytes was once more reverted to its nonionic form by adding sodium hydroxide, as well as phase separation and analytes enrichment were realized simultaneously. Several parameters affecting the approach, such as concentration of sodium dodecyl sulfate, extraction solvent volume, sodium hydroxide concentration, sample phase pH, injection solvent type, and extraction time, were investigated and optimized. The possible microextraction mechanism of double micelle supramolecular inclusion was explored. Under the optimum conditions, the enrichment factors of four protoberberine alkaloids were from 101.8 to 152.0. The linear ranges (with r2  ≥ 0.990) were 0.032-4.23, 0.031-4.33, 0.0026-10.04, and 0.0013-4.13 µg/mL for epiberberine, coptisine, palmatine, and berberine, respectively. The detection limits were in the range of 0.16-0.32 ng/mL. Satisfactory accuracies (recoveries 98.8-104.6%) and precisions (RSDs 1.9-10.9%) were also obtained. The results showed that the approach is rapid, effective, eco-friendly, and easy-to-handle for the enrichment and detection of active alkaloids in Rhizoma coptidis.


Assuntos
Alcaloides de Berberina/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Microextração em Fase Líquida , Dodecilsulfato de Sódio/química , Alcaloides de Berberina/química , Solventes/química
15.
Eur J Pharm Sci ; 110: 77-86, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167234

RESUMO

In our previous study, Rhizoma Coptidis extract was found to exert more potent inhibitory effect than its major component berberine towards urease from Helicobacter pylori (HPU) and jack bean (JBU). In continuation of our work, the present study was designed to further comparatively investigate the urease inhibitory activities of five major protoberberine alkaloids in Rhizoma Coptidis, namely berberine, palmatine, coptisine, epiberberine, jateorhizine to identify the bioactive constituent, and illuminate the potential mechanism of action. Results indicated that the five protoberberine alkaloids acted as concentration-dependent inactivators of urease with IC50 values ranging between 3.0 and 5087µM for HPU and 2.3->10,000µM for JBU, respectively. Notably, epiberberine (EB) was found to be the most potent inhibitor against both ureases with IC50 values of 3.0±0.01µM for HPU and 2.3±0.01µM for JBU, which was more effective than the standard urease inhibitor, acetohydroxamic acid (83±0.01µM for HPU and 22±0.01µM for JBU, respectively). Further kinetic analysis revealed that the type of EB inhibition against HPU was slow-binding and uncompetitive, with Ki of 10.6±0.01µM, while slow-binding and competitive against JBU with Ki of 4.6±0.01µM. Addition of thiol reagents, such as l-cysteine, glutathione and dithiothreitol, significantly abolished the inhibition, while Ni2+ competitive inhibitors, boric acid and sodium fluoride, synergetically inhibited urease with EB, indicating the obligatory role of the active site sulfhydryl group for the inhibition. In addition, binding of EB with the urease proved to be reversible, as about 65% and 90% enzymatic activity of HPU and JBU, respectively, could be restored by dithiothreitol application. These findings highlighted the potential role of Rhizoma Coptidis protoberberine alkaloids, especially EB, as a lead urease inhibitor in the treatment of diseases associated with ureolytic bacteria. Thus, EB had good potential for further development into a promising therapeutic approach for the treatment of urease-related diseases.


Assuntos
Berberina/análogos & derivados , Proteínas de Plantas/antagonistas & inibidores , Urease/antagonistas & inibidores , Berberina/química , Canavalia/enzimologia , Coptis chinensis , Cisteína/química , Ditiotreitol/química , Medicamentos de Ervas Chinesas/química , Glutationa/química , Helicobacter pylori/enzimologia , Ácidos Hidroxâmicos/química , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Urease/química
16.
Xenobiotica ; 46(2): 175-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26134304

RESUMO

1. Organic cation transporters (OCTs) play an important role in drug safety and efficacy. Protoberberine alkaloids are ubiquitous organic cations or weak bases with remarkable biological actives. This study was to elucidate the potential interaction of alkaloids (coptisine, jatrorrhizine, epiberberine, berberrubine, palmatine and corydaline) with OCTs using Madin-Darby canine kidney (MDCK) cells stably expressing human OCT1, OCT2 and OCT3. 2. All the tested alkaloids significantly inhibited the uptake of MPP(+), a model OCT substrate, in MDCK-hOCTs cells with the IC50 of 0.931-9.65 µM. Additionally, coptisine, jatrorrhizine and epiberberine were substrates of all the hOCTs with the Km of 0.273-5.80 µM, whereas berberrubine was a substrate for hOCT1 and hOCT2, but not for hOCT3, the Km values were 1.27 and 1.66 µM, respectively. The transport capacity of coptisine in MDCK cells expressing the variants of hOCT1-P341L or hOCT2-A270S was significantly higher than that in wild-type (WT) cells with the Clint (Vmax/Km) of 379 ± 7.4 and 433 ± 5.7 µl/mg protein/min, respectively. 3. The above data indicate that the tested alkaloids are potent inhibitors, and coptisine, jatrorrhizine, epiberberine and berberrubine are substrates of hOCT1, hOCT2 and/or hOCT3 with high affinity. In addition, the variants (OCT1-P341L and OCT2-A270S) possess higher transport capacity to coptisine than WT hOCTs.


Assuntos
Alcaloides de Berberina/farmacocinética , Fator 3 de Transcrição de Octâmero/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Transportador 1 de Cátions Orgânicos/metabolismo , 1-Metil-4-fenilpiridínio/farmacocinética , Animais , Berberina/análogos & derivados , Berberina/farmacocinética , Células Cultivadas , Cromatografia Líquida , Cães , Humanos , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Fator 3 de Transcrição de Octâmero/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Transportador 1 de Cátions Orgânicos/genética , Transportador 2 de Cátion Orgânico , Polimorfismo Genético , Espectrometria de Massas em Tandem
17.
J Sep Sci ; 38(12): 2117-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25832420

RESUMO

In this work, a novel magnetic nanomaterial functionalized with a molecularly imprinted polymer was prepared for the extraction of protoberberine alkaloids. Molecularly imprinted polymers were made on the surface of Fe3 O4 nanoparticles by using berberine as template, acetonitrile/water as porogen, acrylamide as functional monomer and ethylene glycol dimethacrylate as cross-linker. The optimized molar ratio of template/functional monomer was 1:7. The polymeric magnetic nanoparticles were characterized by transmission electron microscopy and Fourier transform infrared spectroscopy. The stability and adsorption capacity of the molecularly imprinted polymers were investigated. The molecularly imprinted polymers were used as a selective sorbent for the magnetic molecularly imprinted solid-phase extraction and determination of jatrorrhizine, palmatine, and berberine. Extraction parameters were studied including loading pH, sample volume, stirring speed, and extraction time. Finally, a magnetic molecularly imprinted solid-phase extraction coupled to high-performance liquid chromatography method was developed. Under the optimized conditions, the method showed good linear range of 0.1-150 ng/mL for berberine and 0.1-100 ng/mL for jatrorrhizine and palmatine. The limit of detection was 0.01 ng/mL for berberine and 0.02 ng/mL for jatrorrhizine and palmatine. The proposed method has been applied to determine protoberberine alkaloids in Cortex phellodendri and rat plasma samples. The recoveries ranged from 87.33-102.43%, with relative standard deviation less than 4.54% in Cortex phellodendri and from 102.22-111.15% with relative standard deviation less than 4.59% in plasma.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides de Berberina/isolamento & purificação , Nanopartículas de Magnetita/química , Extratos Vegetais/química , Administração Oral , Adsorção , Alcaloides/química , Animais , Berberina/análogos & derivados , Berberina/química , Berberina/isolamento & purificação , Alcaloides de Berberina/química , Cromatografia Líquida de Alta Pressão , Reagentes de Ligações Cruzadas/química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Nanotecnologia , Phellodendron/química , Casca de Planta/química , Extratos Vegetais/administração & dosagem , Polímeros/química , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Recent Adv Phytochem ; 45: 31-75, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27795590

RESUMO

The roots/rhizomes of black cohosh (Actaea racemosa L. syn. Cimicifuga racemosa [L]. Nutt., Ranunculaceae) have been used traditionally by Native Americans to treat colds, rheumatism, and a variety of conditions related to women's health. In recent years black cohosh preparations have become popular dietary supplements among women seeking alternative treatments for menopausal complaints. The popularity of the plant has led to extensive phytochemical and biological investigations, including several clinical trials. Most of the phytochemical and biological research has focused on two abundant classes of compounds: the triterpene glycosides and phenolic acids. A third group of phytoconstituents that has received far less attention consists of the alkaloids and related compounds that contain nitrogen. This chapter summarizes the current state of knowledge of the chemistry and biological activities associated with this group of constituents and provides some perspective on their significance for future research on this interesting plant.

19.
Xenobiotica ; 45(4): 302-11, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25369727

RESUMO

1. Zebrafish has been used in metabolic study of drugs as a powerful tool in recent years. In this study, we make a feasible metabolism investigation of five protoberberine alkaloids (PBAs) applied in zebrafish model for the first time, including berberine (BBR), palmatine (PAL), jatrorrhizine (JAT), coptisine (COP) and epiberberine (EBBR). 2. After exposure for 24 hours, 19 metabolites were identified by LTQ Orbitrap mass spectrometer, including 9 phase I metabolites and 10 phase II metabolites. Demethylation, hydroxylation, sulfation and glucuronidation were the major metabolic transformation of PBAs in zebrafish, which were similar to mammals. Compared with reported literatures, BBR and JAT showed high consistency between human and zebrafish in metabolic pathways. 3. To our knowledge, this is the first time to study in vivo metabolism of COP, which provides useful information to other researchers. 4. This study indicated that zebrafish model is feasible and reasonable to predict the metabolism of PBAs. It showed great potential for developing a novel and rapid method for predicting the metabolism of trace compounds of botanical drugs, with the advantages of lower cost, higher performance and easier set up.


Assuntos
Alcaloides de Berberina/metabolismo , Berberina/análogos & derivados , Animais , Berberina/metabolismo , Cromatografia Líquida de Alta Pressão , Metabolômica , Modelos Animais , Espectrometria de Massas em Tandem , Peixe-Zebra
20.
J Pharm Biomed Anal ; 98: 463-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25023388

RESUMO

A novel hollow fiber cell fishing procedure with high-performance liquid chromatography (HFCF-HPLC) was developed and used for rapid screening, fishing, and analysis of bioactive compounds from traditional Chinese medicines. Human breast cancer cell MCF7, mouse breast cancer cell MADB106, and gastric cancer cell SGC7901 were seeded on the internal surface of hollow fibers that were used to screen, fish, and analyze an antitumor-active protoberberine alkaloid group from Coptis chinensis decoction. The main variables that affect the HFCF-HPLC process were investigated and optimized. The surface properties of the hollow fiber-seeded cells, cell survival rate, non-specific binding between active centers in the hollow fiber and the target compounds, repeatability, reliability, and recovery of HFCF-HPLC were investigated in detail. Several active compounds structures that were screened from Coptis chinensis by using HFCF-HPLC were identified by comparing the retention time of the reference substances. The cell membrane and cell organelle were separated from MCF7 cells for a preliminary study of the target effect of active compounds on MCF7 cells. The living cell, cell membrane, and cell organelle fishing factors of the active compound, as the indexes of drug binding ability in HFCF-HPLC, were defined and discussed. In addition, tamoxifen as positive control substance and indomethacin as negative control substance were screened by using HFCF-HPLC to further verify the method's reliability. The results demonstrated that HFCF-HPLC is an effective, rapid, stable, and reliable method to screen and analyze bioactive compounds.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Alcaloides de Berberina/química , Alcaloides de Berberina/farmacologia , Coptis/química , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Indometacina/química , Indometacina/farmacologia , Células MCF-7 , Medicina Tradicional Chinesa/métodos , Camundongos , Organelas/efeitos dos fármacos , Reprodutibilidade dos Testes , Taxa de Sobrevida , Tamoxifeno/química , Tamoxifeno/farmacologia
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