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1.
Medicine (Baltimore) ; 101(38): e30720, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36197265

RESUMO

To explore the mechanism of action of colchicine in the treatment of acute cerebral infarction (ACI) based on network pharmacology. The Swiss Target Prediction Database and CTD database were used to predict the target information of colchicine. ACI-related targets were retrieved using the GeneCards database, and the target protein interaction network (PPI) and active ingredient-target network were obtained by combining Cytoscape 3.7.1 software and R language. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and gene function analysis (GO) enrichment analysis were performed using R language to preliminarily explore the multiple pharmacological mechanisms of action of colchicine. There were 200 targets identified by network parameter analysis; 958 ACI targets were identified. Overlapping comparisons allowed the extraction of 143 overlapping targets, and the top 30 targets were screened according to the topological isomerization parameters. Component-target networks were constructed. A PPI of overlapping targets was established to identify key targets. In addition, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and GO functional enrichment analysis were performed to explore the multiple mechanisms of action of colchicine in the treatment of ACI. Colchicine treatment of ACI is characterized by multi-component, multi-target and multi-pathway, and can exert complex network regulation through the interaction between different targets, providing a new idea and new basis for further exploration of the mechanism of action of colchicine in the treatment of ACI.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Infarto Cerebral/tratamento farmacológico , Colchicina/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Farmacologia em Rede
2.
Elife ; 102021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34951590

RESUMO

Transition metals, such as zinc, are essential micronutrients in all organisms, but also highly toxic in excessive amounts. Heavy-metal transporting P-type (PIB) ATPases are crucial for homeostasis, conferring cellular detoxification and redistribution through transport of these ions across cellular membranes. No structural information is available for the PIB-4-ATPases, the subclass with the broadest cargo scope, and hence even their topology remains elusive. Here, we present structures and complementary functional analyses of an archetypal PIB-4-ATPase, sCoaT from Sulfitobacter sp. NAS14-1. The data disclose the architecture, devoid of classical so-called heavy-metal-binding domains (HMBDs), and provide fundamentally new insights into the mechanism and diversity of heavy-metal transporters. We reveal several novel P-type ATPase features, including a dual role in heavy-metal release and as an internal counter ion of an invariant histidine. We also establish that the turnover of PIB-ATPases is potassium independent, contrasting to many other P-type ATPases. Combined with new inhibitory compounds, our results open up for efforts in for example drug discovery, since PIB-4-ATPases function as virulence factors in many pathogens.


Heavy metals such as zinc and cobalt are toxic at high levels, yet most organisms need tiny amounts for their cells to work properly. As a result, proteins studded through the cell membrane act as gatekeepers to finetune import and export. These proteins are central to health and disease; their defect can lead to fatal illnesses in humans, and they also help bacteria infect other organisms. Despite their importance, little is known about some of these metal-export proteins. This is particularly the case for PIB-4-ATPases, a subclass found in plants and bacteria and which includes, for example, a metal transporter required for bacteria to cause tuberculosis. Intricate knowledge of the three-dimensional structure of these proteins would help to understand how they select metals, shuttle the compounds in and out of cells, and are controlled by other cellular processes. To reveal this three-dimensional organisation, Grønberg et al. used X-ray diffraction, where high-energy radiation is passed through crystals of protein to reveal the positions of atoms. They focused on a type of PIB-4-ATPases found in bacteria as an example. The work showed that the protein does not contain the metal-binding regions seen in other classes of metal exporters; however, it sports unique features that are crucial for metal transport such as an adapted pathway for the transport of zinc and cobalt across the membrane. In addition, Grønberg et al. tested thousands of compounds to see if they could block the activity of the protein, identifying two that could kill bacteria. This better understanding of how PIB-4-ATPases work could help to engineer plants capable of removing heavy metals from contaminated soils, as well as uncover new compounds to be used as antibiotics.


Assuntos
Íons/metabolismo , Metais Pesados/metabolismo , ATPases do Tipo-P/química , ATPases do Tipo-P/metabolismo , Rhodobacteraceae/enzimologia , Sítios de Ligação , Transporte Biológico , Proteínas de Transporte de Cátions/metabolismo , Modelos Moleculares , ATPases do Tipo-P/classificação , Conformação Proteica , Rhodobacteraceae/classificação , Zinco/metabolismo
3.
Oncol Rep ; 42(3): 1173-1182, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322230

RESUMO

Long non­coding RNAs (lncRNAs) can act as carcinogenic or cancer suppressive factors during the pathogenesis, invasion and metastasis of non­small cell lung cancer (NSCLC). The current study explored the role of long intergenic non­protein coding RNA 00887 (LINC00887) and competing endogenous RNAs (ceRNAs). It was revealed that LINC00887 interacts with several microRNAs (miRs), which regulates downstream genes such as fibronectin 1, MET proto­oncogene, receptor tyrosine kinase and mothers against decapentaplegic homolog 4, which are associated with the spread of lung cancer. The experimental results also suggested that LINC00887 can stimulate miR­613, miR­206 and miR­1­2 to become competing endogenous RNAs, which may regulate the epithelial­mesenchymal transition of NSCLC cells through the transforming growth factor­â signal transduction pathway, and therefore promote the migration of cells and the acquisition of stem cell characteristics. Therefore, it can be concluded that high levels of LINC00887 can accelerate the malignant transformation ability of NSCLC cells.


Assuntos
Adenocarcinoma de Pulmão/secundário , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Movimento Celular , Neoplasias Pulmonares/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Invasividade Neoplásica , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Células Tumorais Cultivadas
4.
Antibodies (Basel) ; 7(4)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31544889

RESUMO

P-type ATPases form a large and ubiquitous superfamily of ion and lipid transporters that use ATP (adenosine triphosphate) to carry out their function. The IB subclass (PIB-ATPases) allows flux of heavy metals and are key players in metal detoxification, critical for human health, crops, and survival of pathogens. Nevertheless, PIB-ATPases remain poorly understood at a molecular level. In this study, nanobodies (Nbs) are selected against the zinc-transporting PIB-ATPase ZntA from Shigella sonnei (SsZntA), aiming at developing tools to assist the characterization of the structure and function of this class of transporters. We identify six different Nbs that bind detergent stabilized SsZntA. We further assess the effect of the Nbs on the catalytic function of SsZntA, and find that five nanobodies associate without affecting the function, while one nanobody significantly reduces the ATPase activity. This study paves the way for more refined mechanistical and structural studies of zinc-transporting PIB-ATPases.

5.
Neurol Sci ; 39(2): 305-311, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29124441

RESUMO

The study aimed to determine the incidence and the onset time of bulbar paralysis (BP) associated with Miller-Fisher syndrome (MFS) and its overlaps, to better understand the clinical characteristics among patients with MFS and its overlaps. Medical records from 48 patients with MFS and its overlaps were divided into two groups based on the presence (MFS-BP+) or absence (MFS-BP-) of BP. Their clinical features, laboratory and electrophysiological findings, neuroimaging data, and treatment plan were analyzed and compared between two groups. The incidence of BP associated with MFS and its overlaps was 48%. Eighty-two percent of the patients developed BP within 1 week after the onset of MFS and its overlaps. The cerebrospinal fluid (CSF) protein level in patients was higher in MFS-BP+ than in MFS-BP- group (67.69 ± 26.59 vs. 50.15 ± 20.44 mg/dl; P < 0.05). Frequencies of severe limb weakness, hypoglossal paralysis, disturbance of consciousness, and tracheal intubation required were also significantly higher in MFS-BP+ than in MFS-BP- group. Positive results of anti-GQ1b and anti-GT1b antibodies were all found in MFS-BP+ group. The prevalence of BP in MFS and its overlap was higher, the majority of BP occurred within 7 days after the onset of the disease, and early diagnosis of BP concurrence is helpful to decide the treatment plan.


Assuntos
Paralisia Bulbar Progressiva/complicações , Paralisia Bulbar Progressiva/epidemiologia , Síndrome de Miller Fisher/complicações , Síndrome de Miller Fisher/epidemiologia , Adulto , Idoso , Povo Asiático , Paralisia Bulbar Progressiva/diagnóstico por imagem , Eletrofisiologia , Feminino , Gangliosídeos/imunologia , Humanos , Imunoglobulina G/sangue , Incidência , Masculino , Pessoa de Meia-Idade , Síndrome de Miller Fisher/diagnóstico por imagem , Neuroimagem , Estudos Retrospectivos
6.
Biol Psychiatry ; 81(8): 654-670, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27916196

RESUMO

BACKGROUND: Stress is a conserved physiological response in mammals. Whereas moderate stress strengthens memory to improve reactions to previously experienced difficult situations, too much stress is harmful. METHODS: We used specific ß-adrenergic agonists, as well as ß2-adrenergic receptor (ß2AR) and arrestin knockout models, to study the effects of adaptive ß2AR activation on cognitive function using Morris water maze and object recognition experiments. We used molecular and cell biological approaches to elucidate the signaling subnetworks. RESULTS: We observed that the duration of the adaptive ß2AR activation determines its consequences on learning and memory. Short-term formoterol treatment, for 3 to 5 days, improved cognitive function; however, prolonged ß2AR activation, for more than 6 days, produced harmful effects. We identified the activation of several signaling networks downstream of ß2AR, as well as an essential role for arrestin and lactate metabolism in promoting cognitive ability. Whereas Gs-protein kinase A-cyclic adenosine monophosphate response element binding protein signaling modulated monocarboxylate transporter 1 expression, ß-arrestin-1 controlled expression levels of monocarboxylate transporter 4 and lactate dehydrogenase A through the formation of a ß-arrestin-1/phospho-mitogen-activated protein kinase/hypoxia-inducible factor-1α ternary complex to upregulate lactate metabolism in astrocyte-derived U251 cells. Conversely, long-term treatment with formoterol led to the desensitization of ß2ARs, which was responsible for its decreased beneficial effects. CONCLUSIONS: Our results not only revealed that ß-arrestin-1 regulated lactate metabolism to contribute to ß2AR functions in improved memory formation, but also indicated that the appropriate management of one specific stress pathway, such as through the clinical drug formoterol, may exert beneficial effects on cognitive abilities.


Assuntos
Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Ácido Láctico/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Receptores Adrenérgicos beta 2/metabolismo , Transdução de Sinais , Estresse Psicológico/metabolismo , beta-Arrestina 1/metabolismo , Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Animais , Astrócitos/metabolismo , Linhagem Celular , Fumarato de Formoterol/administração & dosagem , Hipocampo/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoenzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Receptores Adrenérgicos beta 2/genética , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia , Transcriptoma
7.
Br J Pharmacol ; 172(21): 5050-67, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26248680

RESUMO

BACKGROUND AND PURPOSE: Cholecystokinin (CCK) is secreted by intestinal I cells and regulates important metabolic functions. In pancreatic islets, CCK controls beta cell functions primarily through CCK1 receptors, but the signalling pathways downstream of these receptors in pancreatic beta cells are not well defined. EXPERIMENTAL APPROACH: Apoptosis in pancreatic beta cell apoptosis was evaluated using Hoechst-33342 staining, TUNEL assays and Annexin-V-FITC/PI staining. Insulin secretion and second messenger production were monitored using ELISAs. Protein and phospho-protein levels were determined by Western blotting. A glucose tolerance test was carried out to examine the functions of CCK-8s in streptozotocin-induced diabetic mice. KEY RESULTS: The sulfated carboxy-terminal octapeptide CCK26-33 amide (CCK-8s) activated CCK1 receptors and induced accumulation of both IP3 and cAMP. Whereas Gq -PLC-IP3 signalling was required for the CCK-8s-induced insulin secretion under low-glucose conditions, Gs -PKA/Epac signalling contributed more strongly to the CCK-8s-mediated insulin secretion in high-glucose conditions. CCK-8s also promoted formation of the CCK1 receptor/ß-arrestin-1 complex in pancreatic beta cells. Using ß-arrestin-1 knockout mice, we demonstrated that ß-arrestin-1 is a key mediator of both CCK-8s-mediated insulin secretion and of its the protective effect against apoptosis in pancreatic beta cells. The anti-apoptotic effects of ß-arrestin-1 occurred through cytoplasmic late-phase ERK activation, which activates the 90-kDa ribosomal S6 kinase-phospho-Bcl-2-family protein pathway. CONCLUSIONS AND IMPLICATIONS: Knowledge of different CCK1 receptor-activated downstream signalling pathways in the regulation of distinct functions of pancreatic beta cells could be used to identify biased CCK1 receptor ligands for the development of new anti-diabetic drugs.


Assuntos
Colecistocinina/fisiologia , Ilhotas Pancreáticas/metabolismo , Receptores da Colecistocinina/metabolismo , Transdução de Sinais , Animais , Apoptose/fisiologia , Arrestinas/genética , Colecistocinina/metabolismo , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Knockout , Fosforilação , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , beta-Arrestina 1 , beta-Arrestinas
8.
Exp Mol Pathol ; 98(1): 79-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25533547

RESUMO

Influenza A virus infection is a persistent threat to public health worldwide due to hemagglutinin (HA) variation. Current vaccines against influenza A virus provide immunity to viral isolates similar to vaccine strains. Antibodies against common epitopes provide immunity to diverse influenza virus strains and protect against future pandemic influenza. Therefore, it is vital to analyze common HA antigenic epitopes of influenza virus. In this study, 14 strains of monoclonal antibodies with high sensitivity to common epitopes of influenza virus antigens identified in our previous study were selected as the tool to predict common HA epitopes. The common HA antigenic epitopes were divided into four categories by ELISA blocking experiments, and separately, into three categories according to the preliminary results of computer simulation. Comparison between the results of computer simulations and ELISA blocking experiments indicated that at least two classes of common epitopes are present in influenza virus HA. This study provides experimental data for improving the prediction of HA epitopes of influenza virus (H1 subtype) and the development of a potential universal vaccine as well as a novel approach for the prediction of epitopes on other pathogenic microorganisms.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Anticorpos Monoclonais/classificação , Simulação por Computador , Ensaio de Imunoadsorção Enzimática , Humanos , Influenza Humana/virologia
9.
J Biol Chem ; 289(35): 24215-25, 2014 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-24962568

RESUMO

The very large G protein-coupled receptor 1 (VLGR1) is a core component in inner ear hair cell development. Mutations in the vlgr1 gene cause Usher syndrome, the symptoms of which include congenital hearing loss and progressive retinitis pigmentosa. However, the mechanism of VLGR1-regulated intracellular signaling and its role in Usher syndrome remain elusive. Here, we show that VLGR1 is processed into two fragments after autocleavage at the G protein-coupled receptor proteolytic site. The cleaved VLGR1 ß-subunit constitutively inhibited adenylate cyclase (AC) activity through Gαi coupling. Co-expression of the Gαiq chimera with the VLGR1 ß-subunit changed its activity to the phospholipase C/nuclear factor of activated T cells signaling pathway, which demonstrates the Gαi protein coupling specificity of this subunit. An R6002A mutation in intracellular loop 2 of VLGR1 abolished Gαi coupling, but the pathogenic VLGR1 Y6236fsx1 mutant showed increased AC inhibition. Furthermore, overexpression of another Usher syndrome protein, PDZD7, decreased the AC inhibition of the VLGR1 ß-subunit but showed no effect on the VLGR1 Y6236fsx1 mutant. Taken together, we identified an independent Gαi signaling pathway of the VLGR1 ß-subunit and its regulatory mechanisms that may have a role in the development of Usher syndrome.


Assuntos
Proteínas de Transporte/fisiologia , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Animais , Sequência de Bases , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Primers do DNA , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteólise , Receptores Acoplados a Proteínas G/metabolismo
10.
Diabetologia ; 57(9): 1899-910, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24947582

RESUMO

AIMS/HYPOTHESIS: Somatostatin secretion from islet delta cells plays an important role in regulating islet function and is tightly controlled by environmental changes. Activation of the adrenergic system promoted somatostatin secretion from islet delta cells; however, the role of the adrenergic system in regulating somatostatin content and transcription has not been defined. An imbalance between the somatostatin content and its secretion may cause dysfunctions in the islet delta cells. We have investigated the role of the adrenergic system in the modulation of somatostatin content and transcription in pancreatic delta cells and the detailed underlying mechanisms of this regulation. METHODS: The stress hormone adrenaline (epinephrine), specific adrenergic agonists or specific adrenergic antagonists were applied to islets from either wild-type or specific adrenergic receptor knockout mice and pancreatic delta cell lines to investigate their effects on somatostatin content and transcription. The GloSensor assay, quantitative real-time PCR, western blots and the dual luciferase assay were used to monitor the cAMP level, somatostatin expression, activations of kinases and transcriptional factors. Arrb1 knockout mice, specific Creb or Pax6 mutations and specific kinase inhibitors were used to dissect the signalling pathway. RESULTS: Adrenaline and isoprenaline increased somatostatin content and transcription through the activation of ß1-/ß2-adrenergic receptors (ß1-/ß2ARs). The somatostatin content in ß1AR(-/-) /ß2AR(-/-) (Adrb1/Adrb2 knockout) mice was 50% lower than in ß1AR(+/+)/ß2AR (+/+) mice. Two parallel signalling pathways, Gs-cAMP-protein kinase A (PKA)-cAMP response element binding protein (CREB) and ß-arrestin 1-extracellular signal-related kinase (ERK)-paired box protein 6 (PAX6), cooperatively regulated isoprenaline-induced somatostatin transcription. CONCLUSIONS/INTERPRETATION: A stress pathway increased somatostatin content and transcription through ß-adrenergic agonism. ß-Arrestin1, ERK and PAX6 are important pancreatic delta cell regulators in addition to cAMP, PKA and CREB. Dysfunction of ß-adrenergic agonism may impair pancreatic delta cell function.


Assuntos
Arrestinas/metabolismo , Receptores Adrenérgicos/metabolismo , Células Secretoras de Somatostatina/metabolismo , Somatostatina/metabolismo , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas do Olho/metabolismo , Proteínas de Homeodomínio/metabolismo , Camundongos , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/metabolismo , Proteínas Repressoras/metabolismo , beta-Arrestina 1 , beta-Arrestinas
11.
Biomed Rep ; 1(1): 111-114, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24648904

RESUMO

Immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangement (GR) studies have been successfully employed to investigate the clonality and cell lineage of various lymphoid malignancies. Several lymphoma cell lines, such as BJAB, RAJI, DG75 and Jurkat cell lines, were often used as the positive controls in GR detection assays. Of those, the DG75 B-cell lymphoma line was found to exhibit biclonality [two or more homoduplex and heteroduplex bands in a polymerase chain reaction (PCR) product of clonality assay] in the PCR of GR detection assays. To further explore these characteristics of the biclonal phenomenon, the PCR products were purified and cloned into a pEGM-T clone vector. The sequences were analyzed using DNA analysis software. The results demonstrated that the two bands originated from two forms of GR of DG75 cell lines, i.e., DG75 is a biclonal cell line in Ig GRs, which has not been reported before.

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