RESUMO
Liver fibrosis, one of the leading causes of morbidity and mortality worldwide, lacks effective therapy. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. Luteolin-7-diglucuronide (L7DG) is the major flavonoid extracted from Perilla frutescens and Verbena officinalis. Their beneficial effects in the treatment of liver diseases were well documented. In this study we investigated the anti-fibrotic activities of L7DG and the potential mechanisms. We established TGF-ß1-activated mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 as in vitro liver fibrosis models. Co-treatment with L7DG (5, 20, 50 µM) dose-dependently decreased TGF-ß1-induced expression of fibrotic markers collagen 1, α-SMA and fibronectin. In liver fibrosis mouse models induced by CCl4 challenge alone or in combination with HFHC diet, administration of L7DG (40, 150 mg·kg-1·d-1, i.g., for 4 or 8 weeks) dose-dependently attenuated hepatic histopathological injury and collagen accumulation, decreased expression of fibrogenic genes. By conducting target prediction, molecular docking and enzyme activity detection, we identified L7DG as a potent inhibitor of protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 2.10 µM. Further studies revealed that L7DG inhibited PTP1B activity, up-regulated AMPK phosphorylation and subsequently inhibited HSC activation. This study demonstrates that the phytochemical L7DG may be a potential therapeutic candidate for the treatment of liver fibrosis.
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Aggregation of α-synuclein, a component of Lewy bodies (LBs) or Lewy neurites in Parkinson's disease (PD), is strongly linked with disease development, making it an attractive therapeutic target. Inhibiting aggregation can slow or prevent the neurodegenerative process. However, the bottleneck towards achieving this goal is the lack of such inhibitors. In the current study, we established a high-throughput screening platform to identify candidate compounds for preventing the aggregation of α-synuclein among the natural products in our in-house compound library. We found that a small molecule, 03A10, i.e., (+)-desdimethylpinoresinol, which is present in the fruits of Vernicia fordii (Euphorbiaceae), modulated aggregated α-synuclein, but not monomeric α-synuclein, to prevent further elongation of α-synuclein fibrils. In α-synuclein-overexpressing cell lines, 03A10 (10 µM) efficiently prevented α-synuclein aggregation and markedly ameliorated the cellular toxicity of α-synuclein fibril seeds. In the MPTP/probenecid (MPTP/p) mouse model, oral administration of 03A10 (0.3 mg· kg-1 ·d-1, 1 mg ·kg-1 ·d-1, for 35 days) significantly alleviated behavioral deficits, tyrosine hydroxylase (TH) neuron degeneration and p-α-synuclein aggregation in the substantia nigra (SN). As the Braak hypothesis postulates that the prevailing site of early PD pathology is the gastrointestinal tract, we inoculated α-synuclein preformed fibrils (PFFs) into the mouse colon. We demonstrated that α-synuclein PFF inoculation promoted α-synuclein pathology and neuroinflammation in the gut and brain; oral administration of 03A10 (5 mg· kg-1 ·d-1, for 4 months) significantly attenuated olfactory deficits, α-synuclein accumulation and neuroinflammation in the olfactory bulb and SN. We conclude that 03A10 might be a promising drug candidate for the treatment of PD. 03A10 might be a novel drug candidate for PD treatment, as it inhibits α-synuclein aggregation by modulating aggregated α-synuclein rather than monomeric α-synuclein to prevent further elongation of α-synuclein fibrils and prevent α-synuclein toxicity in vitro, in an MPTP/p mouse model, and PFF-inoculated mice.
Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Doenças Neuroinflamatórias , Substância Negra/metabolismo , Substância Negra/patologia , Encéfalo/metabolismoRESUMO
Dipeptidyl peptidase-4 (DPP4) plays a crucial role in regulating the bioactivity of glucagon-like peptide-1 (GLP-1) that enhances insulin secretion and pancreatic ß-cell proliferation, making it a therapeutic target for type 2 diabetes. Although the crystal structure of DPP4 has been determined, its structure-function mechanism is largely unknown. Here, we examined the biochemical properties of sporadic human DPP4 mutations distal from its catalytic site, among which V486M ablates DPP4 dimerization and causes loss of enzymatic activity. Unbiased molecular dynamics simulations revealed that the distal V486M mutation induces a local conformational collapse in a ß-propeller loop (residues 234-260, defined as the flap) and disrupts the dimerization of DPP4. The "open/closed" conformational transitions of the flap whereby capping the active site, are involved in the enzymatic activity of DPP4. Further site-directed mutagenesis guided by theoretical predictions verified the importance of the conformational dynamics of the flap for the enzymatic activity of DPP4. Therefore, the current studies that combined theoretical modeling and experimental identification, provide important insights into the biological function of DPP4 and allow for the evaluation of directed DPP4 genetic mutations before initiating clinical applications and drug development.
Assuntos
Diabetes Mellitus Tipo 2 , Dipeptidil Peptidase 4 , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/genética , Peptídeo 1 Semelhante ao Glucagon , Humanos , MutaçãoRESUMO
The root Rhynchosia volubilis was widely used for contraception in folk medicine, although its molecular mechanism on antifertility has not yet been revealed. In human sperm, it was reported that the cation channel of sperm, an indispensable cation channel for the fertilization process, could be regulated by various steroid-like compounds in plants. Interestingly, these nonphysiological ligands would also disturb the activation of the cation channel of sperm induced by progesterone. Therefore, this study aimed to explore whether the compounds in R. volubilis affect the physiological regulation of the cation channel of sperm. The bioguided isolation of the whole herb of R. volubilis has resulted in the novel discovery of five new prenylated isoflavonoids, rhynchones Aâ-âE (1: â-â5: ), a new natural product, 5'-O-methylphaseolinisoflavan (6: ) (1H and 13C NMR data, Supporting Information), together with twelve known compounds (7: â-â18: ). Their structures were established by extensive spectroscopic analyses and drawing a comparison with literature data, while their absolute configurations were determined by electronic circular dichroism calculations. The experiments of intracellular Ca2+ signals and patch clamping recordings showed that rhynchone A (1: ) significantly reduced cation channel of sperm activation by competing with progesterone. In conclusion, our findings indicat that rhynchone A might act as a contraceptive compound by impairing the activation of the cation channel of sperm and thus prevent fertilization.
Assuntos
Progesterona , Motilidade dos Espermatozoides , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Humanos , Masculino , Progesterona/análise , Progesterona/metabolismo , Progesterona/farmacologia , Sementes , Espermatozoides/química , Espermatozoides/metabolismoRESUMO
Hsp90 is a potential therapeutic target for tumor, as it maintains the stability of a variety of proteins related to tumor development and progression. Autophagy is a self-degradation process to maintain cellular homeostasis and autophagy inhibitors can suppress tumor growth. In this study, we identified DCZ5248, a triazine derivative, was a dual inhibitor of both Hsp90 and late-autophagy with potent antitumor activity against colon cancer cells in vitro and in vivo. We showed that DCZ5248 (0.1-10 µM) induced dose-dependent degradation of Hsp90 client proteins (AKT, CDK4, CDK6 and RAF-1) in HCT 116 colon cancer cells through a proteasome-dependent pathway. Meanwhile, DCZ5248 (0.3 µM) induced cytoplasmic vacuole formation, LC3 II conversion, p62 protein upregulation, and inhibited autophagy at the late stage in the colon cancer cell lines tested. We further revealed that the inhibition of autophagy was achieved by impairing lysosomal functions through induction of lysosomal acidification and attenuation of lysosomal cathepsin activity. The modulation of autophagy by DCZ5248 was independent of Hsp90 inhibition as the autophagy inhibition was not blocked by Hsp90 knockdown. Importantly, inhibition of both Hsp90 function and autophagy by DCZ5248 induced G1-phase cell cycle arrest, apoptosis, and exerted potent antitumor activity against colon cancer cells both in vitro and in vivo. These findings demonstrate that DCZ5248 is a novel dual inhibitor of Hsp90 and autophagy with potential for colon cancer therapy.
Assuntos
Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Triazinas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Lisossomos/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The chemical constituents of the flower buds of Buddleja officinalis were investigated in this study. Eight compounds were isolated from the water extract of B. officinalis by column chromatography, and their structures were elucidated on the basis of physicochemical properties and spectral data. These compounds were identified as(Z)-hex-3-en-1-ol-1-O-ß-D-glucopyranosyl-(1â2)-[ß-D-xylcopyranosyl-(1â6)]-ß-D-glucopyranoside(1), ebracteatoside B(2), jasmonic acid-11-O-ß-D-glucopyranoside(3), 6-hydroxyluteolin-7-O-ß-D-glucopyranoside(4), luteolin-7-O-galacturonide(5), vicenin-2(6), decaffeoylverbascoside(7), and 6-O-(E)-feruloyl-D-glucopyranoside(8). Compound 1 is a new 3-hexenol glycoside. Compounds 2, 3, and 6 were isolated from Buddleja genus for the first time, and compounds 4 and 5 were isolated from this plant for the first time.
Assuntos
Buddleja , Glicosídeos Cardíacos , Glicosídeos , Extratos VegetaisRESUMO
Berberine, berberrubine, thalifendine, demethyleneberberine, jatrorrhizine, and columbamine are six natural protoberberine alkaloid (PA) compounds that display extensive pharmacological properties and share the same protoberberine molecular skeleton with only slight substitution differences. The oral delivery of most PAs is hindered by their poor bioavailability, which is largely caused by P-glycoprotein (P-gp)-mediated drug efflux. Meanwhile, P-gp undergoes large-scale conformational changes (from an inward-facing to an outward-facing state) when transporting substrates, and these changes might strongly affect the P-gp-binding specificity. To confirm whether these six compounds are substrates of P-gp, to investigate the differences in efflux capacity caused by their trivial structural differences and to reveal the key to increasing their binding affinity to P-gp, we conducted a series of in vivo, in vitro, and in silico assays. Here, we first confirmed that all six compounds were substrates of P-gp by comparing the drug concentrations in wild-type and P-gp-knockout mice in vivo. The efflux capacity (net efflux) ranked as berberrubine > berberine > columbamine ~ jatrorrhizine > thalifendine > demethyleneberberine based on in vitro transport studies in Caco-2 monolayers. Using molecular dynamics simulation and molecular docking techniques, we determined the transport pathways of the six compounds and their binding affinities to P-gp. The results suggested that at the early binding stage, different hydrophobic and electrostatic interactions collectively differentiate the binding affinities of the compounds to P-gp, whereas electrostatic interactions are the main determinant at the late release stage. In addition to hydrophobic interactions, hydrogen bonds play an important role in discriminating the binding affinities.
Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Berberina/análogos & derivados , Berberina/metabolismo , Animais , Berberina/sangue , Células CACO-2 , Humanos , Ligação de Hidrogênio , Fígado/química , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação ProteicaRESUMO
The µ opioid receptor (OR), a member of the class A subfamily of G-protein coupled receptors (GPCRs), is a major target for the treatment of pain. G-protein biased µ-OR agonists promise to be developed as analgesics. Thus, TRV130, the first representative µ-OR ligand with G-protein bias, has entered into phase III clinical trials. To identify the detailed G-protein-biased activation and inactivation mechanisms of the µ-OR, we constructed five µ-OR systems that were in complexes with the G-protein-biased agonists TRV130 and BU72, the antagonists ß-FNA and naltrexone, as well as the free receptor. We performed a series of conventional molecular dynamics simulations and analyses of G-protein-biased activation and inactivation mechanisms of µ-OR. Our results, together with previously reported mutation results, revealed the operating mode of the activation switch composed of residues W6.48 and Y7.43 (Ballesteros/Weinstein numbering), the activity of which was responsible for down- and up-regulation, respectively, of the ß-arrestin signaling, which in turn affected G-protein-biased activation of µ-OR. TRV130 was found to stabilize W6.48 by interacting with Y7.43. In addition, we obtained useful information regarding µ-OR-biased activation, such as strong stabilization of W7.35 through a hydrophobic ring interaction in the TRV130 system. These findings may facilitate understanding of µ-OR biased activation and the design of new biased ligands for GPCRs.
Assuntos
Proteínas de Ligação ao GTP/metabolismo , Morfinanos/metabolismo , Pirróis/metabolismo , Receptores Opioides mu/metabolismo , Compostos de Espiro/metabolismo , Tiofenos/metabolismo , Animais , Proteínas de Ligação ao GTP/química , Ligantes , Camundongos , Simulação de Dinâmica Molecular , Morfinanos/química , Naltrexona/análogos & derivados , Naltrexona/química , Naltrexona/metabolismo , Ligação Proteica , Conformação Proteica , Pirróis/química , Receptores Opioides mu/agonistas , Receptores Opioides mu/antagonistas & inibidores , Receptores Opioides mu/química , Compostos de Espiro/química , Tiofenos/química , Ureia/análogos & derivados , Ureia/química , Ureia/metabolismo , Água/químicaRESUMO
In drug design and discovery, binding affinity and selectivity are two basic properties of a drug candidate. Opioid receptors (ORs) are the main targets of strong analgesics. Like some other class A members of G-protein-coupled receptors (GPCRs), ORs exhibit complex selectivity on their ligands. The diversity of binding activity and selectivity among opioids has deeply attracted researchers for a long time. To investigate the subtype selectivity of µ, δ and κ ORs in detail, using the κ-selective antagonist JDTic as a probe, we performed a series of computational simulations, including molecular dynamics and metadynamics, on JDTic-µ/δ/κ-OR complexes. From the simulations, we found that the decisive factor of JDTic selectivity on the µ-subtype was the 2.63 position, which affected the efficacy of JDTic through changing the dynamics of the Q2.60 residue. In addition to the 2.63-position residue, the 7.35 position was the other crucial aspect of JDTic selectivity for the δ-subtype. Based on the results, we suggest a new concept, the "message-address-efficacy" hypothesis, to explain the relationships among the affinity, selectivity and function between ORs and opioids. Thus, all the detailed dynamics of JDTic-bound ORs might be helpful to deeply understand the subtype selectivity and binding mechanisms of other GPCRs.
Assuntos
Simulação de Acoplamento Molecular , Piperidinas/farmacologia , Receptores Opioides/metabolismo , Tetra-Hidroisoquinolinas/farmacologia , Estrutura Molecular , Piperidinas/química , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/químicaRESUMO
A new prenyleudesmane type diterpene, sinupol (8), and a new capnosane type diterpenoid, sinulacetate (9), were isolated from the Xisha soft coral Sinularia polydactyla along with five known related diterpenes (4-7 and 10). Their structures, including absolute configurations, were determined by extensive spectroscopic analysis, the comparison of their NMR data with those of related compounds, and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations. Both new compounds (8 and 9) exhibited promising inhibitory activity against protein tyrosine phosphatase 1B (PTP1B), a potential drug target for the treatment of type II diabetes and obesity.
Assuntos
Antozoários/química , Diterpenos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Animais , Diterpenos/química , Modelos Moleculares , Estrutura MolecularRESUMO
It has been widely recognized that inflammation, particularly chronic inflammation, can increase the risk of cancer and that the simultaneous treatment of inflammation and cancer may produce excellent therapeutic effects. Berberine, an alkaloid isolated from Rhizoma coptidis, has broad applications, particularly as an antibacterial agent in the clinic with a long history. Over the past decade, many reports have demonstrated that this natural product and its derivatives have high activity against both cancer and inflammation. In this review, we summarize the advances in studing berberine and its derivatives as anti-inflammatory and anti-tumor agents in the digestive system; we also discuss their structure-activity relationship. These data should be useful for the development of this natural product as novel anticancer drugs with anti-inflammation activity.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Berberina/análogos & derivados , Berberina/farmacologia , Sistema Digestório/efeitos dos fármacos , Anti-Inflamatórios/uso terapêutico , Antineoplásicos/uso terapêutico , Berberina/uso terapêutico , Humanos , Relação Estrutura-AtividadeRESUMO
Myocardial injury and ensuing fibrotic alterations impair normal heart architecture and cause cardiac dysfunction. Oxidative stress has been recognized as a key player in the pathogenesis of cardiac injury and progression of cardiac dysfunction, and promoting fibrosis. In the current study we investigated whether luteolin-7-diglucuronide (L7DG), a naturally occurring antioxidant found in edible plants, could attenuate isoproterenol (ISO)-induced myocardial injury and fibrosis in mice and the underlying mechanisms. Myocardial injury and fibrosis were induced in mice via injection of ISO (5 mg·kg-1·d-1, ip) for 5 or 10 d. Two treatment regimens (pretreatment and posttreatment) were employed to administer L7DG (5-40 mg·kg-1·d-1, ip) into the mice. After the mice were euthanized, morphological examinations of heart sections revealed that both L7DG pretreatment and posttreatment regimens significantly attenuated ISO-induced myocardial injury and fibrosis. But the pretreatment regimen caused better protection against ISO-induced myocardial fibrosis than the posttreatment regimen. Furthermore, L7DG pretreatment blocked ISO-stimulated expression of the genes (Cyba, Cybb, Ncf1, Ncf4 and Rac2) encoding the enzymatic subunits of NADPH oxidase, which was the primary source of oxidant production in mammalian cells. Moreover, L7DG pretreatment significantly suppressed ISO-stimulated expression of collagen genes Col1a1, Col1a2, Col3a1, and Col12a1 and non-collagen extracellular matrix genes fibrillin-1, elastin, collagen triple helix repeat containing 1 and connective tissue growth factor. In addition, L7DG pretreatment almost reversed ISO-altered expression of microRNAs that were crosstalking with TGFß-mediated fibrosis, including miR-29c-3p, miR-29c-5p, miR-30c-3p, miR-30c-5p and miR-21. The current study demonstrated for the first time that L7DG is pharmacologically effective in protecting the heart against developing ISO-induced injury and fibrosis, justifying further evaluation of L7DG as a cardioprotective agent to treat related cardiovascular diseases.
Assuntos
Antioxidantes/farmacologia , Cardiomiopatias/tratamento farmacológico , Cardiotônicos/farmacologia , Glucuronatos/farmacologia , Luteolina/farmacologia , Miocárdio/patologia , Animais , Antioxidantes/uso terapêutico , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/patologia , Cardiotônicos/uso terapêutico , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Fibrose/induzido quimicamente , Fibrose/patologia , Fibrose/prevenção & controle , Glucuronatos/isolamento & purificação , Glucuronatos/uso terapêutico , Isoproterenol , Lamiaceae/química , Luteolina/isolamento & purificação , Luteolina/uso terapêutico , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Necrose/induzido quimicamente , Necrose/tratamento farmacológico , Necrose/patologiaRESUMO
The mutation of B-RafV600E is widespread in a variety of human cancers. Its inhibitors vemurafenib and dabrafenib have been launched as drugs for treating unresectable melanoma, demonstrating that B-RafV600E is an ideal drug target. This study focused on developing novel B-RafV600E inhibitors as drug leads against various cancers with B-RafV600E mutation. Using molecular modeling approaches, 200 blockbuster drugs were spliced to generate 283 fragments followed by molecular docking to identify potent fragments. Molecular structures of potential inhibitors of B-RafV600E were then obtained by fragment reassembly followed by docking to predict the bioactivity of the reassembled molecules. The structures with high predicted bioactivity were synthesized, followed by in vitro study to identify potent B-RafV600E inhibitors. A highly potent fragment binding to the hinge area of B-RafV600E was identified via a docking-based structural splicing approach. Using the fragment, 14 novel structures were designed by structural reassembly, two of which were predicted to be as strong as marketed B-RafV600E inhibitors. Biological evaluation revealed that compound 1m is a potent B-RafV600E inhibitor with an IC50 value of 0.05 µmol/L, which was lower than that of vemurafenib (0.13 µmol/L). Moreover, the selectivity of 1m against B-RafWT was enhanced compared with vemurafenib. In addition, 1m exhibits desirable solubility, bioavailability and metabolic stability in in vitro assays. Thus, a highly potent and selective B-RafV600E inhibitor was designed via a docking-based structural splicing and reassembly strategy and was validated by medicinal synthesis and biological evaluation.
Assuntos
Antineoplásicos/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Purinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/síntese química , Imidazóis/química , Imidazóis/farmacologia , Indóis/síntese química , Indóis/química , Indóis/farmacologia , Estrutura Molecular , Oximas/síntese química , Oximas/química , Oximas/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Purinas/síntese química , Purinas/química , Solubilidade , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/farmacologia , VemurafenibRESUMO
AIM: Huanglian-jie-du decoction (HLJDD) is an important multiherb remedy in TCM, which is recently demonstrated to be effective to treat ischemic stroke. Here, we aimed to investigate the pharmacological mechanisms of HLJDD in the treatment of ischemic stroke using systems biology approaches. METHODS: Putative targets of HLJDD were predicted using MetaDrug. An interaction network of putative HLJDD targets and known therapeutic targets for the treatment of ischemic stroke was then constructed, and candidate HLJDD targets were identified by calculating topological features, including 'Degree', 'Node-betweenness', 'Closeness', and 'K-coreness'. The binding efficiencies of the candidate HLJDD targets with the corresponding compositive compounds were further validated by a molecular docking simulation. RESULTS: A total of 809 putative targets were obtained for 168 compositive compounds in HLJDD. Additionally, 39 putative targets were common to all four herbs of HLJDD. Next, 49 major nodes were identified as candidate HLJDD targets due to their network topological importance. The enrichment analysis based on the Gene Ontology (GO) annotation system and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway demonstrated that candidate HLJDD targets were more frequently involved in G-protein-coupled receptor signaling pathways, neuroactive ligand-receptor interactions and gap junctions, which all played important roles in the progression of ischemic stroke. Finally, the molecular docking simulation showed that 170 pairs of chemical components and candidate HLJDD targets had strong binding efficiencies. CONCLUSION: This study has developed for the first time a comprehensive systems approach integrating drug target prediction, network analysis and molecular docking simulation to reveal the relationships between the herbs contained in HLJDD and their putative targets and ischemic stroke-related pathways.
Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Acidente Vascular Cerebral/tratamento farmacológico , Biologia de Sistemas/métodos , Animais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Mineração de Dados , Bases de Dados Genéticas , Combinação de Medicamentos , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genômica , Humanos , Simulação de Acoplamento Molecular , Mapas de Interação de Proteínas , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/metabolismo , Integração de Sistemas , Resultado do Tratamento , Fluxo de TrabalhoRESUMO
(2'R)-2',3'-Dihydro-2'-(1-hydroxy-1-methylethyl)-2,6'-bibenzofuran-6,4'-diol (DHMB) is a natural compound extracted from Morus notabilis. It was found that DHMB acts as a competitive inhibitor against mushroom tyrosinase with a Ki value of 14.77 µM. Docking results further indicated that it could form strong interactions with one copper ion with a distance of 2.7 Å, suggesting the mechanism of inhibition might be due to chelating copper ions in the active site. Furthermore, melanin production in B16-F10 murine melanoma cells was significantly inhibited by DHMB in a concentration-dependent manner without cytotoxicity. The results of western blotting also showed that DHMB decreased 3-isobuty-1-methxlzanthine-induced mature tyrosinase expression. Taken together, these findings indicated that DHMB may be a new promising pigmentation-altering agent for agriculture, cosmetic, and therapeutic applications.
Assuntos
Agaricales/enzimologia , Benzofuranos/química , Melaninas/biossíntese , Melanoma Experimental/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , AMP Cíclico/metabolismo , Inibidores Enzimáticos/química , Camundongos , Simulação de Acoplamento Molecular , Morus/químicaRESUMO
AIM: To develop a reliable computational approach for predicting potential drug targets based merely on protein sequence. METHODS: With drug target and non-target datasets prepared and 3 classification algorithms (Support Vector Machine, Neural Network and Decision Tree), a multi-algorithm and multi-model based strategy was employed for constructing models to predict potential drug targets. RESULTS: Twenty one prediction models for each of the 3 algorithms were successfully developed. Our evaluation results showed that â¼30% of human proteins were potential drug targets, and â¼40% of putative targets for the drugs undergoing phase II clinical trials were probably non-targets. A public web server named D3TPredictor (http://www.d3pharma.com/d3tpredictor) was constructed to provide easy access. CONCLUSION: Reliable and robust drug target prediction based on protein sequences is achieved using the multi-algorithm and multi-model strategy.
Assuntos
Algoritmos , Desenho Assistido por Computador , Bases de Dados de Proteínas , Descoberta de Drogas/métodos , Internet , Proteoma , Sequência de Aminoácidos , Árvores de Decisões , Humanos , Redes Neurais de Computação , Reprodutibilidade dos Testes , Relação Estrutura-Atividade , Máquina de Vetores de SuporteRESUMO
AIM: A large number of drug-induced long QT syndromes are ascribed to blockage of hERG potassium channels. The aim of this study was to construct novel computational models to predict compounds blocking hERG channels. METHODS: Doddareddy's hERG blockage data containing 2644 compounds were used, which divided into training (2389) and test (255) sets. Laplacian-corrected Bayesian classification models were constructed using Discovery Studio. The models were internally validated with the training set of compounds, and then applied to the test set for validation. Doddareddy's experimentally validated dataset with 60 compounds was used for external test set validation. RESULTS: A Bayesian classification model considering the effects of four molecular properties (Mw, PPSA, ALogP and pKa_basic) as well as extended-connectivity fingerprints (ECFP_14) exhibited a global accuracy (91%), parameter sensitivity (90%) and specificity (92%) in the test set validation, and a global accuracy (58%), parameter sensitivity (61%) and specificity (57%) in the external test set validation. CONCLUSION: The novel model is better than those in the literatures for predicting compounds blocking hERG channels, and can be used for large-scale prediction.
Assuntos
Descoberta de Drogas/métodos , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Teorema de Bayes , Simulação por Computador , Bases de Dados de Produtos Farmacêuticos , Canais de Potássio Éter-A-Go-Go/metabolismo , Humanos , Modelos BiológicosRESUMO
Two new sulfated sesquiterpenoids, megastigman-7-ene-3, 5, 6, 9-tetrol-3-O-ß-D-6'-sulfonated-glucopyranoside (1) and 3-O-ß-D-6'-sulfonated-glucopyranosyl-6-(3-oxo-2-butenylidenyl)-1, 1, 5-trimethylcyclohexan-5-ol (2), along with one known sesquitepenoid compound icariside B1 (3) were isolated from the whole herb of Petasites tricholobus Franch. Their structures were identified by their chemical and spectroscopic characters. All obtained compounds were tested for their cytotoxicity against four cancer cell lines.
Assuntos
Petasites/química , Sesquiterpenos/farmacologia , Linhagem Celular Tumoral , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Humanos , Norisoprenoides/isolamento & purificação , Norisoprenoides/farmacologia , Sesquiterpenos/isolamento & purificaçãoRESUMO
(M)-Bicelaphanol A (1) and (P)-bicelaphanol A (2), two unprecedented dimeric trinorditerpenes existing as atropisomers, together with their monomer celaphanol A (3), were isolated from the root bark of Celastrus orbiculatus. The structures and absolute configurations of 1 and 2 were determined by spectroscopic and single-crystal X-ray diffraction analyses. Compound 1 exhibited a significant in vitro neuroprotective effect against a hydrogen peroxide-induced cell viability decrease in PC12 cells at 1 µM, while compounds 2 and 3 showed such effects at 10 µM.