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1.
BMC Psychiatry ; 23(1): 383, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37259053

RESUMO

BACKGROUND: Functional impairment affects many patients with schizophrenia. Treatment with the long-acting injectable antipsychotic aripiprazole once-monthly (AOM) may help improve functioning. OBJECTIVES: To explore changes in functioning in patients with schizophrenia who received AOM treatment in observational studies. METHODS: Here we report functional outcomes in the form of Global Assessment of Functioning (GAF) scores in a pooled analysis of data from two observational studies from Canada (NCT02131415) and Germany (vfa non-interventional studies registry 15960N). Data from 396 patients were analyzed. RESULTS: At baseline, the mean GAF score was 47.7 (SD 13.4). During 6 months of treatment with AOM, the mean GAF score increased to 59.4 (SD 15.8). Subgroups stratified by patient age (≤35 years/>35 years), sex, disease duration (≤5 years/>5 years) and disease severity at baseline had all significantly improved their GAF at month 6. 51.5% of the patients showed a GAF score increase of at least 10 points, which was regarded as clinically meaningful, and were considered responders. CONCLUSIONS: These data show that treatment with AOM may help improve patient functioning in a routine treatment setting. TRIAL REGISTRATION: NCT02131415 (May 6, 2014), vfa non-interventional studies registry 15960N.


Assuntos
Antipsicóticos , Esquizofrenia , Adulto , Humanos , Antipsicóticos/uso terapêutico , Aripiprazol/uso terapêutico , Canadá , Preparações de Ação Retardada/uso terapêutico , Gravidade do Paciente , Esquizofrenia/tratamento farmacológico , Masculino , Feminino
2.
BMC Psychiatry ; 22(1): 773, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482352

RESUMO

BACKGROUND: ReLiAM, Real-Life Assessment of Abilify Maintena, was the first reported long-term prospective non-interventional study for patients with schizophrenia treated with aripiprazole once-monthly injectable formulation (AOM) under real-life conditions. ReLiAM's primary aim was to evaluate the evolution of global functional status in patients treated with AOM for 12 months in Canada. METHODS: The objective of this post hoc analysis of the ReLiAM study is to investigate the treatment effects of real-life use of AOM over a 1-year period in the subgroup of patients with reported substance use compared with patients without substance use. RESULTS: The results of this post hoc analysis demonstrate that treatment with AOM for 12 months in patients with schizophrenia was comparably effective in improving global functioning in subgroups of patients with and without concomitant substance use. CONCLUSIONS: These results support the use of AOM for the treatment of schizophrenia in patients with or without concomitant substance use. TRIAL REGISTRATION: ClinicalTrials.gov NCT02131415, first posted on May 6, 2014. Overall trial status: Terminated.


Assuntos
Esquizofrenia , Transtornos Relacionados ao Uso de Substâncias , Humanos , Aripiprazol/uso terapêutico , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Estudos Prospectivos , Canadá
3.
BMC Psychiatry ; 19(1): 114, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30991969

RESUMO

BACKGROUND: With previously established efficacy of aripiprazole once-monthly injectable formulation (AOM) in pre-registration randomized controlled trials, the current study was designed to evaluate its effectiveness in patients treated for schizophrenia in regular clinical settings in Canada. METHODS: Following their clinicians' decision to prescribe AOM, 193 patients with a diagnosis of schizophrenia, were recruited from 17 Canadian community or hospital-based settings. The primary outcome of global functioning was assessed with the Global Assessment of Functioning Scale (GAF) at 3-month intervals for 1 year. Secondary outcomes (social and occupational functioning and illness severity) and adverse drug reactions (ADR) were also assessed. RESULTS: A majority of the 169 evaluable patients were within the first 5 years of diagnosis (early phase). A linear mixed model analysis showed a significant main effect of time (Type III test p < 0.001) after adjusting for baseline GAF score, with a change in mean GAF scores from 49 at baseline to 61 at 12 months. No differences between early vs late phase were observed. Results on secondary outcome measures of function (Social and Occupational Functioning Scale) and illness severity (Clinical Global Impression-Severity Scale and Brief Psychiatric Rating Scale) were similar. Serious ADRs were observed in 29 (14.6%) patients and akathisia in 18 (9.1%) patients. At month-12, significant (≥7%) weight gain was observed in 25.7% (n = 27/105) of patients. CONCLUSIONS: Treatment with AOM is effective in improving symptoms and functioning in schizophrenia patients treated in regular clinical settings. Akathisia was infrequent while one quarter of patients gained clinically significant weight. TRIAL REGISTRATION: Unique identifier: NCT02131415 . First posted: 06 May 2014.


Assuntos
Antipsicóticos/administração & dosagem , Aripiprazol/administração & dosagem , Esquizofrenia/tratamento farmacológico , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Adolescente , Adulto , Antipsicóticos/efeitos adversos , Aripiprazol/efeitos adversos , Escalas de Graduação Psiquiátrica Breve , Canadá/epidemiologia , Estudos de Coortes , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Esquizofrenia/diagnóstico , Resultado do Tratamento , Aumento de Peso/efeitos dos fármacos , Aumento de Peso/fisiologia , Adulto Jovem
4.
Retrovirology ; 10: 96, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-24020926

RESUMO

BACKGROUND: HIV-1 translation is modulated by the activation of the interferon (IFN)-inducible Protein Kinase RNA-activated (PKR). PKR phosphorylates its downstream targets, including the alpha subunit of the eukaryotic translation Initiation Factor 2 (eIF2α), which decreases viral replication. The PKR Activator (PACT) is known to activate PKR after a cellular stress. In lymphocytic cell lines, HIV-1 activates PKR only transiently and not when cells replicate the virus at high levels. The regulation of this activation is due to a combination of viral and cellular factors that have been only partially identified. RESULTS: PKR is transiently induced and activated in peripheral blood mononuclear cells after HIV-1 infection. The addition of IFN reduces viral replication, and induces both the production and phosphorylation of PKR. In lymphocytic Jurkat cells infected by HIV-1, a multiprotein complex around PKR contains the double-stranded RNA binding proteins (dsRBPs), adenosine deaminase acting on RNA (ADAR)1 and PACT. In HEK 293T cells transfected with an HIV-1 molecular clone, PACT unexpectedly inhibited PKR and eIF2α phosphorylation and increased HIV-1 protein expression and virion production in the presence of either endogenous PKR alone or overexpressed PKR. The comparison between different dsRBPs showed that ADAR1, TAR RNA Binding Protein (TRBP) and PACT inhibit PKR and eIF2α phosphorylation in HIV-infected cells, whereas Staufen1 did not. Individual or a combination of short hairpin RNAs against PACT or ADAR1 decreased HIV-1 protein expression. In the astrocytic cell line U251MG, which weakly expresses TRBP, PACT mediated an increased HIV-1 protein expression and a decreased PKR phosphorylation. In these cells, a truncated PACT, which constitutively activates PKR in non-infected cells showed no activity on either PKR or HIV-1 protein expression. Finally, PACT and ADAR1 interact with each other in the absence of RNAs. CONCLUSION: In contrast to its previously described activity, PACT contributes to PKR dephosphorylation during HIV-1 replication. This activity is in addition to its heterodimer formation with TRBP and could be due to its binding to ADAR1. HIV-1 has evolved to replicate in cells with high levels of TRBP, to induce the expression of ADAR1 and to change the function of PACT for PKR inhibition and increased replication.


Assuntos
HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Proteínas de Ligação a RNA/metabolismo , Replicação Viral , eIF-2 Quinase/antagonistas & inibidores , Adenosina Desaminase/metabolismo , Linhagem Celular , Humanos , Fosforilação , Ligação Proteica , Multimerização Proteica , Processamento de Proteína Pós-Traducional
5.
J Virol ; 85(17): 8460-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21490091

RESUMO

Adenosine deaminase acting on RNA 1 (ADAR1) is a double-stranded RNA binding protein and RNA-editing enzyme that modifies cellular and viral RNAs, including coding and noncoding RNAs. This interferon (IFN)-induced protein was expected to have an antiviral role, but recent studies have demonstrated that it promotes the replication of many RNA viruses. The data from these experiments show that ADAR1 directly enhances replication of hepatitis delta virus, human immunodeficiency virus type 1, vesicular stomatitis virus, and measles virus. The proviral activity of ADAR1 occurs through two mechanisms: RNA editing and inhibition of RNA-activated protein kinase (PKR). While these pathways have been found independently, the two mechanisms can act in concert to increase viral replication and contribute to viral pathogenesis. This novel type of proviral regulation by an IFN-induced protein, combined with some antiviral effects of hyperediting, sheds new light on the importance of ADAR1 during viral infection and transforms our overall understanding of the innate immune response.


Assuntos
Adenosina Desaminase/metabolismo , Edição de RNA , Vírus de RNA/fisiologia , RNA Viral/metabolismo , Replicação Viral , eIF-2 Quinase/antagonistas & inibidores , Humanos , Modelos Biológicos , Proteínas de Ligação a RNA
6.
Rev Med Virol ; 21(1): 42-53, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21294215

RESUMO

Recent therapeutic approaches against HIV-1 include IFN in combination therapy for patients with coinfections or as an alternative strategy against the virus. These treatment options require a better understanding of the weak efficacy of the IFN-stimulated genes, such as the protein kinase RNA-activated (PKR), which results in viral progression. Activated PKR has a strong antiviral activity on HIV-1 expression and production in cell culture. However, PKR is not activated upon HIV-1 infection when the virus reaches high levels of replication, due to viral and cellular controls. PKR is activated by low levels of the HIV-1 trans-activation response (TAR) RNA element, but is inhibited by high levels of this double-stranded RNA. The viral Tat protein also counteracts PKR activation by several mechanisms. In addition, HIV-1 replicates only in cells that have a high level of the TAR RNA binding protein (TRBP), a strong inhibitor of PKR activation. Furthermore, increased levels of adenosine deaminase acting on RNA (ADAR1) are observed when HIV-1 replicates at high levels and the protein binds to PKR and inhibits its activation. Finally, the PKR activator (PACT) also binds to PKR during HIV-1 replication with no subsequent kinase activation. The combination of all the inhibiting pathways that prevent PKR phosphorylation contributes to a high HIV-1 production in permissive cells. Enhancing PKR activation by counteracting its inhibitory partners could establish an increased innate immune antiviral pathway against HIV-1 and could enhance the efficacy of the IFN treatment.


Assuntos
Regulação para Baixo , Infecções por HIV/enzimologia , HIV-1/fisiologia , Replicação Viral , eIF-2 Quinase/antagonistas & inibidores , Animais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Humanos , Inibidores de Proteínas Quinases/farmacologia , Replicação Viral/efeitos dos fármacos , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
7.
Eur Psychiatry ; 65(1): e42, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35855645

RESUMO

BACKGROUND: Noninterventional naturalistic studies are an important complement to randomized controlled trials. Aripiprazole once-monthly (AOM) is an atypical antipsychotic in a long-acting injectable formulation. METHODS: A pooled analysis of two noninterventional studies was undertaken to validate previous results on AOM effectiveness and safety in a larger population and improve statistical power for preplanned subgroup analyses. We analyzed data from 409 patients with schizophrenia who were treated with AOM and were enrolled in noninterventional studies in Germany (via noninterventional studies registry 15,960 N) and Canada (NCT02131415). Data collected at baseline, 3 and 6 months were analyzed. Among the endpoints were psychopathology (brief psychiatric rating scale [BPRS]) and disease severity (clinical global impression [CGI]). RESULTS: Mean patient age was 38.9 (SD 14.8) years, and 59.9% were male. BPRS decreased from 48.1 (SD 15.6) at baseline to 36.5 (SD 13.7) at month 6 (p < 0.001). CGI decreased from 4.47 (SD 0.90) at baseline to 3.64 (SD 1.16) at month 6 (p < 0.001). A total of 54.4% were responders (at least 20% reduction) on the BPRS, and 56.5% had a CGI-S-score that was at least 1 level better than baseline. A total of 43.4% were considered responders on both the BPRS and CGI scales. A total of 45.2% were considered in remission. Adverse events were rare and corresponded to the previously known safety profile of AOM. CONCLUSIONS: Treatment with AOM for patients with schizophrenia appeared effective and safe under real-life conditions.


Assuntos
Antipsicóticos , Aripiprazol , Esquizofrenia , Adulto , Antipsicóticos/efeitos adversos , Aripiprazol/efeitos adversos , Escalas de Graduação Psiquiátrica Breve , Canadá , Estudos Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/tratamento farmacológico , Resultado do Tratamento
8.
Ther Adv Psychopharmacol ; 11: 20451253211013148, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025982

RESUMO

BACKGROUND: Anxiety symptoms are common in patients with major depressive disorder (MDD) and usually confer worse treatment outcomes. The long-term, open-label AtWoRC study in working patients with MDD treated with vortioxetine demonstrated a significant correlation between severity of anxiety symptoms and impaired work productivity. This analysis was undertaken to further explore clinical characteristics and treatment outcomes in patients with different levels of severity of anxiety symptoms at baseline. METHODS: Post hoc analysis in 199 working patients with MDD treated with vortioxetine (10-20 mg/day), stratified by Generalized Anxiety Disorder 7-item (GAD-7) score at baseline [mild/moderate anxiety (GAD-7 ⩽14), n = 83; severe anxiety (GAD-7 ⩾15), n = 116]. Associations were examined between GAD-7 and other outcome assessment scores at baseline. Observed mean changes from baseline to week 52 were compared between groups. RESULTS: Patients with severe anxiety had significantly worse depressive and cognitive symptoms, functioning, and work productivity at baseline than those with mild/moderate anxiety, but similar cognitive performance. Statistically significant improvements from baseline were seen for all outcomes after 52 weeks of vortioxetine treatment, with no significant differences observed between the two groups after adjustment for baseline anxiety scores. CONCLUSION: Treatment with vortioxetine was associated with long-term improvement in clinical symptoms and measures of work productivity in patients with MDD in a real-world setting, irrespective of severity of anxiety symptoms at the start of treatment.

9.
J Virol ; 83(19): 10119-28, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19605474

RESUMO

The interferon-induced protein kinase RNA activated (PKR) is activated after virus infection. This activation is transient during the human immunodeficiency virus type 1 (HIV-1) infection of lymphocytes, and the protein is not activated at the peak of infection. We observed that interferon-induced adenosine deaminase acting on RNA 1-p150 (ADAR1-p150) and ADAR1-p110 expression increases while the virus replicates actively. Furthermore, both forms of ADAR1 show enhanced interactions with PKR at the peak of HIV infection, suggesting a role for this protein in the regulation of PKR activation. We observed that ADAR1-p150, as previously shown for the TAR RNA binding protein (TRBP), reverses the PKR inhibition of HIV expression and production in HEK 293T cells. This activity requires the Z-DNA binding motif and the three double-stranded RNA binding domains but not the catalytic domain. In astrocytic cells, ADAR1-p150 increased HIV expression and production to an extent similar to that of TRBP. Small interfering RNAs against ADAR1-p150 moderately decreased HIV production. These results indicate that two interferon-induced proteins, ADAR1 and PKR, have antagonistic functions on HIV production. They suggest that ADAR1 and TRBP belong to a multiprotein complex that inhibits PKR during the HIV infection of lymphocytes.


Assuntos
Adenosina Desaminase/genética , Adenosina Desaminase/fisiologia , Regulação Viral da Expressão Gênica , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Linfócitos/virologia , Replicação Viral , eIF-2 Quinase/metabolismo , Motivos de Aminoácidos , Linhagem Celular , Fator de Iniciação 2 em Eucariotos/metabolismo , HIV-1/metabolismo , Humanos , Células Jurkat , Modelos Biológicos , Fosforilação , Proteínas de Ligação a RNA , Transfecção
10.
J Occup Environ Med ; 62(3): e94-e101, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31895735

RESUMO

OBJECTIVE: To assess changes in workplace productivity and functioning in an open-label study in working patients receiving vortioxetine (10 to 20 mg/d) for major depressive disorder (MDD). METHODS: Associations between items in the Work Limitations Questionnaire (WLQ), the Sheehan Disability Scale (SDS), and the Work Productivity and Activity Impairment (WPAI) questionnaire were assessed at 12 and 52 weeks by Pearson correlation coefficients. RESULTS: Significant improvements were observed across all domains of workplace productivity and functioning after 12 and 52 weeks' vortioxetine treatment. Strong correlations were seen between improvements in WLQ mental domains and WPAI presenteeism and SDS work/school items. Presenteeism showed stronger correlations with other workplace productivity measures than absenteeism. CONCLUSIONS: Presenteeism and absenteeism impact productivity in working patients with MDD. Vortioxetine confers long-term benefits across all workplace functioning domains.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Eficiência , Presenteísmo/estatística & dados numéricos , Desempenho Profissional , Absenteísmo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Local de Trabalho
11.
RNA Biol ; 5(2): 92-103, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18421256

RESUMO

The double-stranded (ds) RNA binding proteins, TRBP and PACT bind the interferon-induced protein kinase PKR and dsRNA. TRBP inhibits, whereas PACT activates PKR. They have two dsRNA binding domains (dsRBDs) and a C-terminal domain that does not bind RNA. All three domains show a strong homology between the two proteins. Interaction assays by in vitro binding, yeast two-hybrid, and immunoprecipitations show that TRBP and PACT form heterodimers in the absence of dsRNA. In cells, TRBP and PACT colocalize in specific dots of the perinuclear space. Analysis of the individual domains shows that the two dsRBDs of each protein interact with each other. In contrast, the C-terminal domain of PACT homodimerizes and interacts with its homologous region in TRBP, but the same domain in TRBP does not homodimerize. Because the C-terminal domain in TRBP binds to the tumor suppressor Merlin, the RNase III Dicer and PACT, we name it the Merlin Dicer PACT liaison (Medipal) domain. Based on known interactions Medipal is defined as aminoacids 228-366 in TRBP and 195-313 in PACT. TRBP-PACT interaction correlates with an absence of eIF2alpha activation by PACT, suggesting that the heterodimer does not activate PKR. We propose that the Medipal domain mediates specialized functions through protein-protein interactions and contributes to the RNA interference pathway and to PKR activation.


Assuntos
Mapeamento de Interação de Proteínas , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Núcleo Celular/metabolismo , Dimerização , Fator de Iniciação 2 em Eucariotos/metabolismo , Células HeLa , Humanos , Modelos Biológicos , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , RNA/metabolismo , Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade , Técnicas do Sistema de Duplo-Híbrido
12.
J Mol Biol ; 355(5): 898-910, 2006 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-16343534

RESUMO

HIV-1 viral production is restricted intracellularly in astrocytes compared with lymphocytes due to the limited expression of viral structural proteins. The poor translation of HIV-1 mRNA and consequent limited virion production can be restored by overexpression of TRBP proteins in the astrocytoma U251MG cells. TRBP1 and TRBP2 are double-stranded RNA binding proteins that increase HIV-1 gene expression. Both proteins are produced from a single gene that possesses two independent promoters and an alternative first exon. Endogenous expression is restricted in astrocytes due to limited TRBP promoter expression compared to lymphocytes. We examined the transcriptional regulation of TRBP1 and TRBP2 by in vivo genomic footprinting in the lymphocytic Jurkat and in the astrocytic U251MG cells. We identified one AP4 and one AP2-binding site that regulate the TRBP2 promoter in both cell types, and one Sp1 and two CCAAT-binding sites that control TRBP1 expression. Mutations in the TRBP1 promoter modulate its expression specifically in Jurkat and in U251MG. The analysis of the CCAAT-390 site by EMSA and by ChIP demonstrates that NF-Y/CBF transcription factor binds specifically to the promoter in vitro and in vivo. Furthermore, each NF-Y subunit was more highly expressed in the lymphocytic cells, compared to astrocytic cells. An NF-YA trans-dominant mutant decreased TRBP1 promoter expression fourfold in Jurkat cells, thus demonstrating the functional importance of NF-Y factors in lymphocytes. These studies suggest that the cell specifity of HIV-1 expression and replication may be regulated, in part, through the control of TRBP1 expression.


Assuntos
Astrócitos/fisiologia , Fator de Ligação a CCAAT/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Linfócitos/fisiologia , Regiões Promotoras Genéticas , Isoformas de Proteínas , Astrócitos/citologia , Astrocitoma , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Genes Reporter , HIV-1/genética , HIV-1/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Jurkat , Linfócitos/citologia , Dados de Sequência Molecular , Coativadores de Receptor Nuclear , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Distribuição Tecidual , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
13.
Retrovirology ; 2: 65, 2005 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-16253139

RESUMO

Increasing evidence indicates that RNA interference (RNAi) may be used to provide antiviral immunity in mammalian cells. Human micro (mi)RNAs can inhibit the replication of a primate virus, whereas a virally-encoded miRNA from HIV inhibits its own replication. Indirect proof comes from RNAi suppressors encoded by mammalian viruses. Influenza NS1 and Vaccinia E3L proteins can inhibit RNAi in plants, insects and worms. HIV-1 Tat protein and Adenovirus VA RNAs act as RNAi suppressors in mammalian cells. Surprisingly, many RNAi suppressors are also inhibitors of the interferon (IFN)-induced protein kinase R (PKR) but the potential overlap between the RNAi and the IFN pathways remains to be determined. The link between RNAi as an immune response and the IFN pathway may be formed by a cellular protein, TRBP, which has a dual role in HIV replication and RNAi. TRBP has been isolated as an HIV-1 TAR RNA binding protein that increases HIV expression and replication by inhibiting PKR and by increasing translation of structured RNAs. A recent report published in the Journal of Virology shows that the poor replication of HIV in astrocytes is mainly due to a heightened PKR response that can be overcome by supplying TRBP exogenously. In two recent papers published in Nature and EMBO Reports, TRBP is now shown to interact with Dicer and to be required for RNAi mediated by small interfering (si) and micro (mi)RNAs. The apparent discrepancy between TRBP requirement in RNAi and in HIV replication opens the hypotheses that RNAi may be beneficial for HIV-1 replication or that HIV-1 may evade the RNAi restriction by diverting TRBP from Dicer and use it for its own benefit.


Assuntos
HIV/fisiologia , Interferência de RNA , Proteínas de Ligação a RNA/fisiologia , Replicação Viral , HIV/imunologia , Humanos , Imunidade Inata , Ribonuclease III/metabolismo
14.
J Virol ; 79(20): 12763-72, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16188979

RESUMO

Acute human immunodeficiency virus type 1 (HIV-1) replication in astrocytes produces minimal new virus particles due, in part, to inefficient translation of viral structural proteins despite high levels of cytoplasmic viral mRNA. We found that a highly reactive double-stranded (ds) RNA-binding protein kinase (PKR) response in astrocytes underlies this inefficient translation of HIV-1 mRNA. The dsRNA elements made during acute replication of HIV-1 in astrocytes triggers PKR activation and the specific inhibition of HIV-1 protein translation. The heightened PKR response results from relatively low levels of the cellular antagonist of PKR, the TAR RNA binding protein (TRBP). Efficient HIV-1 production was restored in astrocytes by inhibiting the innate PKR response to HIV-1 dsRNA with dominant negative PKR mutants, or PKR knockdown by siRNA gene silencing. Increasing the expression of TRBP in astrocytes restored acute virus production to levels comparable to those observed in permissive cells. Therefore, the robust innate PKR antiviral response in astrocytes results from relatively low levels of TRBP expression and contributes to their restricted infection. Our findings highlight TRBP as a novel cellular target for therapeutic interventions to block productive HIV-1 replication in cells that are fully permissive for HIV-1 infection.


Assuntos
HIV-1/crescimento & desenvolvimento , Proteínas de Ligação a RNA/fisiologia , eIF-2 Quinase/metabolismo , Astrócitos/imunologia , Astrócitos/metabolismo , Astrócitos/virologia , Células Cultivadas , Regulação para Baixo , HIV-1/metabolismo , Humanos , Imunidade Inata , Biossíntese de Proteínas , Proteínas de Ligação a RNA/metabolismo , eIF-2 Quinase/antagonistas & inibidores
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