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1.
Curr Top Med Chem ; 24(15): 1279-1290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38639276

RESUMO

The multifaceted benefits of Lepisanthes fruticosa position it is not only as a promising agricultural commodity but also as a versatile resource with implications for health, biodiversity, and economic growth. Lepisanthes fruticosa has a rich history of traditional use for treating various ailments such as fever and diarrhea. Beyond its traditional uses, the plant's antioxidant properties suggest potential applications in combating oxidative stress-related conditions. Its antihyperglycemic properties indicate promise in managing elevated blood sugar levels, while its antibacterial and antiviral attributes hint at potential applications in infectious disease control. Furthermore, the plant's anticancer properties add to its appeal as a valuable resource in the realm of medical research. The plant also exhibits considerable potential in addressing a range of health concerns, including non-communicable diseases and infections, antidiarrheal, and antiviral properties. In essence, Lepisanthes fruticose emerges as more than just an agricultural asset. Its unique combination of nutritional richness, health benefits, and economic viability underscores its potential to become a valuable asset both locally and on the global stage. In this current review, we are discussed about the ethnopharmacology, nutritional value, therapeutic effects, phytochemistry, and toxicology of Lepisanthes fruticose.


Assuntos
Compostos Fitoquímicos , Humanos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Valor Nutritivo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Animais , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação
2.
Med Chem ; 19(3): 297-309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35713125

RESUMO

BACKGROUND: The severe acute respiratory syndrome coronavirus-2 is causing a disaster through coronavirus disease-19 (COVID-19), affecting the world population with a high mortality rate. Although numerous scientific efforts have been made, we do not have any specific drug for COVID-19 treatment. OBJECTIVE: Aim of the present study was to analyse the molecular interaction of nitrogen heterocyclic based drugs (hydroxychloroquine, remdesivir and lomefloxacin) with various SARSCoV- 2 proteins (RdRp, PLPro, Mpro and spike proteins) using a molecular docking approach. METHODS: We have performed docking study using PyRx software, and Discovery Studio Visualizer was used to visualise the molecular interactions. The designed nitrogen heterocyclic analogues were checked for Lipinski's rule of five, Veber's Law and Adsorption, Distribution, Metabolism, and Excretion (ADME) threshold. After obtaining the docking results of existing nitrogen heterocyclic drugs, we modified the selected drugs to get molecules with better affinity against SARS-CoV-2. RESULTS: Hydroxychloroquine bound to RdRp, spike protein, PLPro and Mpro at -5.2, -5.1, -6.7 and -6.0 kcal/mol, while remdesivir bound to RdRp, spike protein, PLPro, and Mpro at -6.1, -6.9, -6.4 and -6.9 kcal/mol, respectively. Lomefloxacin bound to RdRp, spike protein, PLPro and Pro at -6.4, -6.6, -7.2 and -6.9 kcal/mol. ADME studies of all these compounds indicated lipophilicity and high gastro intestine absorbability. The modified drug structures possess better binding efficacy towards at least one target than their parent compounds. CONCLUSION: The outcome reveals that the designed nitrogen heterocyclics could contribute to developing the potent inhibitory drug SARS-CoV-2 with strong multi-targeted inhibition ability and reactivity.


Assuntos
COVID-19 , Compostos Heterocíclicos , Humanos , SARS-CoV-2 , Simulação de Acoplamento Molecular , Tratamento Farmacológico da COVID-19 , Hidroxicloroquina , Glicoproteína da Espícula de Coronavírus , Compostos Heterocíclicos/farmacologia , RNA Polimerase Dependente de RNA , Simulação de Dinâmica Molecular , Antivirais/farmacologia
3.
J Biomol Struct Dyn ; 41(19): 9256-9266, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36411738

RESUMO

Candidates generated from unsaturated ketone (chalcone) demonstrated as strong, reversible and specific monoamine oxidase-B (MAO-B) inhibitory activity. For the research on MAO-B inhibition, our team has synthesized and evaluated a panel of aldoxime-chalcone ethers (ACE) and hydroxylchalcones (HC). The MAO-B inhibitory activity of several candidates is in the micro- to nanomolar range in these series. The purpose of this research was to develop predictive QSAR models and look into the relation between MAO-B inhibition by aldoxime and hydroxyl-functionalized chalcones. It was shown that the molecular descriptors ETA Shape P, MDEO-12, ETA dBetaP, SpMax1 Bhi and ETA EtaP B are significant in the inhibitory action of the MAO-B target. Using the current 2D QSAR models, potential chalcone-based MAO-B inhibitors might be created. The lead molecules were further analyzed by the detailed molecular dynamics study to establish the stability of the ligand-enzyme complex.Communicated by Ramaswamy H. Sarma.


Assuntos
Chalcona , Chalconas , Chalconas/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade , Monoaminoxidase , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular
4.
Saudi J Biol Sci ; 29(12): 103458, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36187455

RESUMO

COVID-19 is a progressing pandemic of coronavirus disease-2019, which had drowned the whole world in a deep sorrow sea. Uncountable deaths were extending the list of deaths every single day. The present research was aimed to study the multi-target interaction of coumarins against COVID-19 using molecular docking analysis. The structure of coumarin compounds was checked for ADME and Lipinski rule of five by using SwissADME, an online tool. SARS-CoV-2 proteins such as RdRp, PLpro, Mpro and spike protein were collected from the Protein Data Bank. The molecular docking study was performed in the PyRx tool, and the molecular interactions were visualised by Discovery Studio Visualizer. All the coumarin compounds used in the study were obeyed Lipinski's rule of 5 without any violations. All the three designed derivatives of phenprocoumon, hymecromone, and psoralen were showed high binding affinity and prominent interactions with the drug target. The presence of -OH groups in the compound, His41, a catalytic dyad in Mpro, number of and the distance of hydrogen bond interactions with SARS-CoV-2 targets was accountable for the high binding attractions. The modified drug structures possess better binding efficacy towards at least three targets compared to their parent compounds. Further, molecular dynamic studies can be suggested to find the ligand-protein complex stability. The present study outcome reveals that the designed coumarins can be synthesised and examined as a potent inhibitory drug of SARS-CoV-2.

5.
Saudi Pharm J ; 29(10): 1205-1215, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34703373

RESUMO

Autoinjectors are self-injectable devices; they are important class of medical devices which can deliver drugs through subcutaneous or intramuscular route. They enclose prefilled syringes or cartridges which are driven by a spring system. The major benefits of this device are easy self-administration, improved patient compliance, reduced anxiety, and dosage accuracy. Immediate treatment during emergency conditions such as anaphylaxis, migraine, and status epilepticus or for chronic conditions like psoriasis, diabetes, multiple sclerosis, and rheumatoid arthritis, Reformulation of first-generation biologics, technical advancements, innovative designs, patient compliance, overwhelming interest for self-administration all these made entry of more and more autoinjectors into use. In this review, intensive efforts have been made for exploring the different types of currently available autoinjectors for the management of emergency and chronic diseases.

6.
Curr Drug Discov Technol ; 17(4): 507-514, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31424372

RESUMO

About 95% of earth living space lies deep below the ocean's surface and it harbors extraordinary diversity of marine organisms. Marine biodiversity is an exceptional reservoir of natural products, bioactive compounds, nutraceuticals and other potential compounds of commercial value. Timeline for the development of the drug from a plant, synthetic and other alternative sources is too lengthy. Exploration of the marine environment for potential bioactive compounds has gained focus and huge opportunity lies ahead for the exploration of such vast resources in the ocean. Further, the evolution of superbugs with increasing resistance to the currently available drugs is alarming and it needs coordinated efforts to resolve them. World Health Organization recommends the need and necessity to develop effective bioactive compounds to combat problems associated with antimicrobial resistance. Based on these factors, it is imperative to shift the focus towards the marine environment for potential bioactive compounds that could be utilized to tackle antimicrobial resistance. Current research trends also indicate the huge strides in research involving marine environment for drug discovery. The objective of this review article is to provide an overview of marine resources, recently reported research from marine resources, challenges, future research prospects in the marine environment.


Assuntos
Anti-Infecciosos/farmacologia , Organismos Aquáticos/química , Produtos Biológicos/farmacologia , Descoberta de Drogas/métodos , Infecções/tratamento farmacológico , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/uso terapêutico , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/uso terapêutico , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Humanos , Infecções/microbiologia
7.
Molecules ; 23(12)2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30551671

RESUMO

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum absorbance (λmax) of 420 nm. SEM and TEM images revealed DSAgNPs were spherical and rod shaped, with a size range of 20 nm and 75 nm. The zeta potential was found to be -15.41 mV. XRD and EDX analyses confirmed the nature and presence of Ag and AgCl. DSAgNPs showed considerable antibacterial activity, exhibited better cytotoxicity against brine shrimp, and shown better photocatalytic activity against methylene blue. Based on the present research work, it can be concluded that DSAgNPs could be used in the field of water treatment, pharmaceuticals, biomedicine, biosensor and nanotechnology in near future.


Assuntos
Anti-Infecciosos/farmacologia , Bombacaceae/química , Química Verde/métodos , Luz , Nanopartículas Metálicas/química , Extratos Vegetais/química , Sementes/química , Prata/química , Animais , Artemia/efeitos dos fármacos , Catálise , Morte Celular/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana
8.
Med Chem ; 14(7): 733-740, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807521

RESUMO

BACKGROUND: The development of severe drug resistance caused by the extensive use of anti-HIV agents has resulted in a greatly extensive reduction in these drugs efficacy. OBJECTIVES: To identify the important pharmacophoric features and correlate 3D chemical structure of benzothiazinimines with their anti-HIV potential using 2D, 3D-QSAR and pharmacophore modeling studies. METHODS: QSAR and pharmacophore mapping studies have been used to relate structural features. 2D QSAR and 3D QSAR studies were performed using partial least square and k-nearest neighbor methodology, coupled with various feature selection methods, viz. stepwise, genetic algorithm, and simulated annealing, to derive QSAR models which were further validated for statistical significance. RESULTS: The physicochemical descriptor XAHydrophilicArea and SsOHE-index, and alignmentindependent descriptor T_C_Cl_6 showed significant correlation with the anti-HIV activity of benzothiazinimines in 2D QSAR. 3D QSAR results showed the significant effect of electrostatic and steric field descriptors in the anti-HIV potential of benzothiazinimines. The generated pharmacophore hypothesis demonstrated the importance of aromaticity and hydrogen bond acceptors. CONCLUSION: The significant models obtained in this study suggested that these techniques could be used as a guidance for designing new benzothiazinimines with enhanced anti-HIV potential.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , Infecções por HIV , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Software , Relação Estrutura-Atividade
9.
Chem Biol Drug Des ; 81(5): 557-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23452185

RESUMO

The 1,3,4-thiadiazole nucleus is one of the most important and well-known heterocyclic nuclei, which is a common and integral feature of a variety of natural products and medicinal agents. Thiadiazole nucleus is present as a core structural component in an array of drug categories such as antimicrobial, anti-inflammatory, analgesic, antiepileptic, antiviral, antineoplastic, and antitubercular agents. The broad and potent activity of thiadiazole and their derivatives has established them as pharmacologically significant scaffolds. In this study, an attempt has been made with recent research findings on this nucleus, to review the structural modifications on different thiadiazole derivatives for various pharmacological activities.


Assuntos
Tiadiazóis/química , Estrutura Molecular , Relação Estrutura-Atividade
10.
Bioorg Med Chem ; 20(11): 3378-95, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22546204

RESUMO

Thiazolidinone is considered as a biologically important active scaffold that possesses almost all types of biological activities. Successful introduction of ralitoline as a potent anti-convulsant, etozoline as a antihypertensive, pioglitazone as a hypoglycemic agent and thiazolidomycin activity against streptomyces species proved potential of thiazolidinone moiety. This diversity in the biological response profile has attracted the attention of many researchers to explore this skeleton to its multiple potential against several activities. This review is complementary to earlier reviews and aims to review the work reported on various biological activities of thiazolidinone derivatives from year 2000 to the beginning of 2011. Data are presented for active compounds, some of which have passed the preclinical testing stage.


Assuntos
Tiazolidinedionas/química , Tiazolidinedionas/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Anticonvulsivantes/química , Anticonvulsivantes/farmacologia , Antidepressivos/química , Antidepressivos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antituberculosos/química , Antituberculosos/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Estrutura Molecular , Pioglitazona , Receptor Muscarínico M1/agonistas , Streptomyces/efeitos dos fármacos , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia , Tiazolidinedionas/síntese química
11.
Virol J ; 8: 443, 2011 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-21933387

RESUMO

BACKGROUND: Xenotropic Murine Leukemia Virus-related (XMRV) virus is a recently identified mouse gammaretrovirus that has the ability to infect certain human cells. In this study, we investigated the susceptibility of primary neuronal cell types to infection with XMRV. FINDINGS: We observed that the human primary progenitors, progenitor-derived neurons, and progenitor-derived astrocytes supported XMRV multiplication. Interestingly, both progenitors and progenitor-derived neurons were more susceptible compared with progenitor-derived astrocytes. In addition, XMRV-infected Jurkat cells were able to transmit infection to neuronal cells. CONCLUSIONS: These data suggest that neuronal cells are susceptible for XMRV infection.


Assuntos
Astrócitos/virologia , Suscetibilidade a Doenças , Células Jurkat/virologia , Células-Tronco Neurais/virologia , Neurônios/virologia , Infecções por Retroviridae/virologia , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/genética , Animais , Astrócitos/citologia , Diferenciação Celular , Humanos , Imuno-Histoquímica , Células Jurkat/citologia , Masculino , Camundongos , Células-Tronco Neurais/citologia , Neurônios/citologia , Cultura Primária de Células , Neoplasias da Próstata/virologia , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/metabolismo , Infecções por Retroviridae/transmissão , Células Tumorais Cultivadas , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/metabolismo , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/patogenicidade
12.
Virol J ; 8: 423, 2011 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21896167

RESUMO

BACKGROUND: XMRV is a gammaretrovirus first identified in prostate tissues of Prostate Cancer (PC) patients and later in the blood cells of patients with Chronic Fatigue Syndrome (CFS). Although XMRV is thought to use XPR1 for cell entry, it infects A549 cells that do not express XPR1, suggesting usage of other receptors or co-receptors. METHODS: To study the usage of different receptors and co- receptors that could play a role in XMRV infection of lymphoid cells and GHOST (GFP- Human osteosarcoma) cells expressing CD4 along with different chemokine receptors including CCR1, CCR2, etc., were infected with XMRV. Culture supernatants and cells were tested for XMRV replication using real time quantitative PCR. RESULTS: Infection and replication of XMRV was seen in a variety of GHOST cells, LNCaP, DU145, A549 and Caski cell lines. The levels of XMRV replication varied in different cell lines showing differential replication in different cell lines. However, replication in A549 which lacks XPR1 expression was relatively higher than DU145 but lower than, LNCaP. XMRV replication varied in GHOST cell lines expressing CD4 and each of the co- receptors CCR1-CCR8 and bob. There was significant replication of XMRV in CCR3 and Bonzo although it is much lower when compared to DU145, A549 and LNCaP. CONCLUSION: XMRV replication was observed in GHOST cells that express CD4 and each of the chemokine receptors ranging from CCR1- CCR8 and BOB suggesting that infectivity in hematopoietic cells could be mediated by use of these receptors.


Assuntos
Neoplasias Ósseas/virologia , Osteossarcoma/virologia , Receptores de Quimiocinas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/metabolismo , Receptores Virais/metabolismo , Replicação Viral , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/fisiologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Antígenos CD4/biossíntese , Linhagem Celular , Síndrome de Fadiga Crônica/genética , Síndrome de Fadiga Crônica/metabolismo , Síndrome de Fadiga Crônica/virologia , Expressão Gênica , Humanos , Masculino , Especificidade de Órgãos , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/virologia , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Quimiocinas/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Receptores Virais/genética , Receptor do Retrovírus Politrópico e Xenotrópico
13.
Chem Biol Drug Des ; 78(3): 464-70, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21615706

RESUMO

A series of 1,3-thiazolidin-4-one derivatives were prepared by the reaction of respective aromatic amine, aromatic aldehyde, and thioglycolic acid in dry benzene/toluene. The newly synthesized compounds were characterized on the basis of elemental analysis, IR, (1) HNMR, and mass spectra. The newly synthesized final compounds were evaluated for their in vitro antibacterial, antifungal, and anti-viral activities. Preliminary results indicated that some of the compounds demonstrated antibacterial activity in the range of 7-13 µg/mL, antifungal activity in the range of 13-17 µg/mL, comparable with the standard drugs, ciprofloxacin and fluconazole. Structure-activity relationship studies revealed that the nature of the substituents at the 2 and 3 positions of the thiazolidinone nucleus had a significant impact on the in vitro antimicrobial and anti-viral activity of these classes of agents.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antivirais/química , Antivirais/farmacologia , Tiazolidinas/química , Tiazolidinas/farmacologia , Anti-Infecciosos/síntese química , Antivirais/síntese química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Desenho de Fármacos , Fungos/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Tiazolidinas/síntese química , Viroses/tratamento farmacológico , Vírus/efeitos dos fármacos
14.
Eur J Med Chem ; 45(7): 2791-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20347187

RESUMO

A linear quantitative structure activity relationship (QSAR) model is presented for modeling and predicting the inhibition of HIV-1 integrase. The model was produced by using the stepwise multiple linear regression technique on a database that consists of 67 recently discovered 1,3,4-oxadiazole substituted naphthyridine derivatives. The developed QSAR model was evaluated for statistical significance and predictive power. The key conclusion of this study is that valence connectivity index order 1, lowest unoccupied molecular orbital and dielectric energy significantly affect the inhibition of HIV-1 integrase activity by 1,3,4-oxadiazole substituted naphthyridine derivatives. The selected physicochemical descriptors serve as a first guideline for the design of novel and potent antagonists of HIV-1 integrase.


Assuntos
Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , Naftiridinas/química , Naftiridinas/farmacologia , Oxidiazóis/química , Relação Quantitativa Estrutura-Atividade , Modelos Moleculares , Análise de Regressão , Software
15.
Glia ; 57(9): 971-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19062179

RESUMO

14-3-3 Isoforms are shown to be upregulated or accumulated in the glial cells of autopsied patient brains affected with progressive multifocal leukoencephalopathy (PML), a demylinating disease caused by JC virus (JCV). The possible involvement of 14-3-3 in JCV tropism, however, has never been examined. To investigate a potential relationship between 14-3-3 isoforms and JCV in vitro, we examined the localization of six 14-3-3 isoforms in human neural progenitors and progenitor-derived astrocytes (PDAs) in cells without JCV exposure. The 14-3-3 zeta isoform was initially localized in the progenitor cytoplasm. When differentiation of progenitors into PDAs was induced, the zeta isoform was translocated into the nucleus. However, upon JCV infection, progenitor cells exhibited an uncharacteristic 14-3-3 zeta nuclear presence in the few cells that became infected. JCV-treated PDAs showed elevated levels of 14-3-3 zeta compared with noninfected PDAs. Treatment with TGF-beta1, a known stimulant of JCV multiplication, increased the overall number of infected cells and the otherwise absent nuclear presence of 14-3-3 zeta in progenitors. These results suggest that the nuclear presence of 14-3-3 zeta may play a role in JCV infection, and that the isoform may in part determine JCV susceptibility in these cell types.


Assuntos
Proteínas 14-3-3/metabolismo , Astrócitos/metabolismo , Vírus JC/fisiologia , Neurônios/metabolismo , Células-Tronco/metabolismo , Transporte Ativo do Núcleo Celular , Astrócitos/virologia , Western Blotting , Núcleo Celular/metabolismo , Núcleo Celular/virologia , Células Cultivadas , Imunofluorescência , Humanos , Imunoensaio , Neurônios/virologia , Células-Tronco/virologia , Fator de Crescimento Transformador beta1/metabolismo
16.
J Gen Virol ; 89(Pt 6): 1396-1401, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18474555

RESUMO

JC virus (JCV) DNA replication occurs in the nuclei of infected cells. The level of JCV genome expression depends on nucleotide sequences in the viral regulatory region and their interaction with host-cell nuclear transcription factors. Our previous studies showed a higher level of NF-1X in JCV-permissive cells compared with the other members of the NF-1 family, NF-1A, B and C, which suggests that NF-1X plays a positive role in JCV multiplication. It remained unclear whether a reduction in the level of NF-1A, which is expressed abundantly in JCV-non-permissive cell types, leads to an increase in JCV multiplication. In this study, we show that downregulation of NF-1A expression in JCV-non-susceptible progenitor and HeLa cells results in a reversion to susceptibility for JCV multiplication. These data demonstrate that a higher level of NF-1A protein in JCV-non-permissive cell types, compared with the level of NF-1X, may be acting as a negative regulator at the JCV promoter to control JCV multiplication.


Assuntos
Vírus JC/fisiologia , Fatores de Transcrição NFI/fisiologia , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Núcleo Celular/virologia , Células Cultivadas , Regulação para Baixo , Feto , Células HeLa , Humanos , Células-Tronco , Telencéfalo , Replicação Viral
17.
J Virol ; 81(12): 6412-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17409139

RESUMO

The multiplication of the human neurotropic polyomavirus JC virus (JCV) is regulated by cell membrane receptors and nuclear transcription factors. Signaling pathways also play a role in determining the extent to which JCV can productively infect cells. These data show that constitutively active MEK1 protein (CA-MEK1), overexpressed in cultures of human glia, supports a substantial increase in late JCV protein (Vp-1) synthesis. The specificity of this pathway was indicated by no significant enhancement of JCV multiplication through activation of other components of mitogen-activated protein kinase pathways such as p38, Jun N-terminal protein kinase, and protein kinase A. Further evidence supporting the importance of signaling in JCV infection came from addition of transforming growth factor beta1 (TGF-beta1), which stimulated a 200% increase of Vp-1 expression. Specific MEK1/2 inhibitors, flavenoid PD98059 and U0126, decreased the basal and TGF-beta1-stimulated Vp-1 expression by 95% or more. TGF-beta1 is known to phosphorylate/activate Smad DNA binding proteins that could subsequently bind or increase binding to JCV promoter sequences, linking the effects of signaling with JCV transcriptional regulation. The effectiveness with which MEK1/2 inhibitors block JCV multiplication provides insight that may contribute to development of compounds directed against JCV.


Assuntos
Vírus JC/metabolismo , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo , Replicação Viral , Linhagem Celular , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Regulação Viral da Expressão Gênica , Humanos , Transdução de Sinais , Células-Tronco/virologia , Transfecção
18.
Proteomics ; 6(20): 5628-36, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16991198

RESUMO

The human polyomavirus JC virus (JCV) is responsible for the CNS demyelination observed in cases of progressive multifocal leukoencephalopathy. The JCV regulatory region (promoter) is a hypervariable, noncoding, nucleotide sequence positioned between the early and late protein-coding regions in the viral genome. Selective binding of cellular transcription factors to this promoter region participates in the control of viral tropism. Hence, further study of these proteins might provide new insights into JCV tropism and associated pathogenesis. This review gives an overview of viral proteomics - the study of all proteins expressed from the viral gene transcripts, and all the cellular proteins that play a role in JCV tropism. It also describes a new biochemical approach for studying relevant JCV promoter-binding proteins, which is an anchored-JCV transcriptional promoter (ATP) assay. An ATP assay utilizes the product of PCR-amplified JCV promoter sequences coupled with Sepharose beads in order to capture and isolate cellular nuclear proteins with specific promoter-binding affinity for analysis. Proteins that bind to JCV-ATPs can be eluted and subjected to proteomic analysis. Insights from this approach may improve the understanding of viral and cellular parameters that control JCV tropism.


Assuntos
Vírus JC/metabolismo , Proteômica/métodos , Proteínas Virais/química , Desoxirribonuclease I/metabolismo , Genoma Viral , Polyomavirus/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo , Transcrição Gênica , Tropismo
19.
J Virol ; 80(21): 10506-13, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16928756

RESUMO

The infectious cycle of the human polyomavirus JC (JCV) is ultimately regulated in cellular nuclei at the level of viral protein expression and genomic replication. Such activity is prompted by interactions between variant nucleotide sequences within the JCV regulatory region (promoter) and cellular transcription factors that bind specific DNA consensus sites. In previous work we identified an NF-1 class member, NF-1X, as a critical transcription factor affecting the JCV cellular host range. Within variant JCV promoters, as well as other viral and cellular promoters, adjacently located NF-1 and AP-1 consensus sites are often found. The close proximity of these two binding sites suggests the opportunity for interaction between NF-1 and AP-1 proteins. Here, by electrophoretic mobility shift assays, we show temporal and dose-dependent interference by an AP-1 family member, c-Jun, upon NF-1 proteins binding an NF-1 consensus site derived from JCV promoter sequence. Moreover, as demonstrated by protein-protein interaction assays, we identify specific binding affinity independent of DNA binding between NF-1X and c-Jun. Finally, to compare the binding profiles of NF-1X and c-Jun on JCV promoter sequence in parallel with in vivo detection of viral activity levels, we developed an anchored transcriptional promoter (ATP) assay. With use of extracts from JCV-infected cells transfected to overexpress either NF-1X or c-Jun, ATP assays showed concurrent increases in NF-1X binding and viral protein expression. Conversely, increased c-Jun binding accompanied decreases in both NF-1X binding and viral protein expression. Therefore, inhibition of NF-1X binding by c-Jun appears to play a role in regulating levels of JCV activity.


Assuntos
Vírus JC/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fatores de Transcrição NFI/metabolismo , Sítios de Ligação/genética , Células Cultivadas , DNA Viral/genética , DNA Viral/metabolismo , Genes Virais , Humanos , Técnicas In Vitro , Vírus JC/patogenicidade , Vírus JC/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Células-Tronco Multipotentes/virologia , Fatores de Transcrição NFI/genética , Neurônios/virologia , Regiões Promotoras Genéticas , Ligação Proteica , Biossíntese de Proteínas , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
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