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1.
Am J Respir Cell Mol Biol ; 63(1): 46-56, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32176858

RESUMO

Goblet cell metaplasia, excessive mucus production, and inadequate mucus clearance accompany and exacerbate multiple chronic respiratory disorders, such as asthma and chronic obstructive pulmonary disease. Notch signaling plays a central role in controlling the fate of multiple cell types in the lung, including goblet cells. In the present study, we explored the therapeutic potential of modulating the Notch pathway in the adult murine lung using chemically modified antisense oligonucleotides (ASOs). To this end, we designed and characterized ASOs targeting the Notch receptors Notch1, Notch2, and Notch3 and the Notch ligands Jag1 (Jagged 1) and Jag2 (Jagged 2). Pulmonary delivery of ASOs in healthy mice or mice exposed to house dust mite, a commonly used mouse model of asthma, resulted in a significant reduction of the respective mRNAs in the lung. Furthermore, ASO-mediated knockdown of Jag1 or Notch2 in the lungs of healthy adult mice led to the downregulation of the club cell marker Scgb1a1 and the concomitant upregulation of the ciliated cell marker FoxJ1 (forkhead box J1). Similarly, ASO-mediated knockdown of Jag1 or Notch2 in the house dust mite disease model led to reduced goblet cell metaplasia and decreased mucus production. Because goblet cell metaplasia and excessive mucus secretion are a common basis for many lung pathologies, we propose that ASO-mediated inhibition of JAG1 could provide a novel therapeutic path for the treatment of multiple chronic respiratory diseases.


Assuntos
Células Caliciformes/efeitos dos fármacos , Células Caliciformes/metabolismo , Proteína Jagged-1/metabolismo , Pulmão/efeitos dos fármacos , Metaplasia/tratamento farmacológico , Metaplasia/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Animais , Asma/metabolismo , Biomarcadores/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pyroglyphidae , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
2.
JCI Insight ; 4(12)2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31217349

RESUMO

African Americans develop end-stage renal disease at a higher rate compared with European Americans due to 2 polymorphisms (G1 and G2 risk variants) in the apolipoprotein L1 (APOL1) gene common in people of African ancestry. Although this compelling genetic evidence provides an exciting opportunity for personalized medicine in chronic kidney disease, drug discovery efforts have been greatly hindered by the fact that APOL1 expression is lacking in rodents. Here, we describe a potentially novel physiologically relevant genomic mouse model of APOL1-associated renal disease that expresses human APOL1 from the endogenous human promoter, resulting in expression in similar tissues and at similar relative levels as humans. While naive APOL1-transgenic mice did not exhibit a renal disease phenotype, administration of IFN-γ was sufficient to robustly induce proteinuria only in APOL1 G1 mice, despite inducing kidney APOL1 expression in both G0 and G1 mice, serving as a clinically relevant "second hit." Treatment of APOL1 G1 mice with IONIS-APOL1Rx, an antisense oligonucleotide (ASO) targeting APOL1 mRNA, prior to IFN-γ challenge robustly and dose-dependently inhibited kidney and liver APOL1 expression and protected against IFN-γ-induced proteinuria, indicating that the disease-relevant cell types are sensitive to ASO treatment. Therefore, IONIS-APOL1Rx may be an effective therapeutic for APOL1 nephropathies and warrants further development.


Assuntos
Apolipoproteína L1/genética , Interferon gama , Oligonucleotídeos Antissenso/uso terapêutico , Proteinúria/tratamento farmacológico , Proteinúria/etiologia , Animais , Linhagem Celular , Feminino , Humanos , Camundongos , Camundongos Transgênicos
3.
Genome Biol ; 19(1): 4, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29334995

RESUMO

BACKGROUND: About 11% of all human genetic diseases are caused by nonsense mutations that generate premature translation termination codons (PTCs) in messenger RNAs (mRNA). PTCs not only lead to the production of truncated proteins, but also often result in  decreased mRNA abundance due to  nonsense-mediated mRNA decay (NMD). Although pharmacological inhibition of NMD could be an attractive therapeutic approach for the treatment of diseases caused by nonsense mutations, NMD also regulates the expression of 10-20% of the normal transcriptome. RESULTS: Here, we investigate whether NMD can be inhibited to stabilize mutant mRNAs, which may subsequently produce functional proteins, without having a major impact on the normal transcriptome. We develop antisense oligonucleotides (ASOs) to systematically deplete each component in the NMD pathway. We find that ASO-mediated depletion of each NMD factor elicits different magnitudes of NMD inhibition in vitro and are differentially tolerated in normal mice. Among all of the NMD factors, Upf3b depletion is well tolerated, consistent with previous reports that UPF3B is not essential for development and regulates only a subset of the endogenous NMD substrates. While minimally impacting the normal transcriptome, Upf3b-ASO treatment significantly stabilizes the PTC-containing dystrophin mRNA in mdx mice and coagulation factor IX mRNA in a hemophilia mouse model. Furthermore, when combined with reagents promoting translational read-through, Upf3b-ASO treatment leads to the production of functional factor IX protein in hemophilia mice. CONCLUSIONS: These data demonstrate that ASO-mediated reduction of the NMD factor Upf3b could be an effective and safe approach for the treatment of diseases caused by nonsense mutations.


Assuntos
Códon sem Sentido , Degradação do RNAm Mediada por Códon sem Sentido , Oligonucleotídeos Antissenso , Proteínas de Ligação a RNA/antagonistas & inibidores , Animais , Células Cultivadas , Distrofina/genética , Fator IX/metabolismo , Hemofilia B/genética , Hemofilia B/metabolismo , Hemofilia B/terapia , Fígado/metabolismo , Camundongos , Estabilidade de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Transcriptoma
4.
J Clin Invest ; 128(1): 359-368, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29202483

RESUMO

Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by duplication of peripheral myelin protein 22 (PMP22) and is the most common hereditary peripheral neuropathy. CMT1A is characterized by demyelination and axonal loss, which underlie slowed motor nerve conduction velocity (MNCV) and reduced compound muscle action potentials (CMAP) in patients. There is currently no known treatment for this disease. Here, we show that antisense oligonucleotides (ASOs) effectively suppress PMP22 mRNA in affected nerves in 2 murine CMT1A models. Notably, initiation of ASO treatment after disease onset restored myelination, MNCV, and CMAP almost to levels seen in WT animals. In addition to disease-associated gene expression networks that were restored with ASO treatment, we also identified potential disease biomarkers through transcriptomic profiling. Furthermore, we demonstrated that reduction of PMP22 mRNA in skin biopsies from ASO-treated rats is a suitable biomarker for evaluating target engagement in response to ASO therapy. These results support the use of ASOs as a potential treatment for CMT1A and elucidate potential disease and target engagement biomarkers for use in future clinical trials.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Doença de Charcot-Marie-Tooth/tratamento farmacológico , Neurônios Motores/metabolismo , Proteínas da Mielina/antagonistas & inibidores , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Pele/metabolismo , Potenciais de Ação/genética , Animais , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/metabolismo , Doença de Charcot-Marie-Tooth/patologia , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neurônios Motores/patologia , Proteínas da Mielina/biossíntese , Proteínas da Mielina/genética , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Pele/patologia
5.
J Infect Dis ; 216(2): 198-202, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28838145

RESUMO

Epstein-Barr virus (EBV) causes infectious mononucleosis and can lead to lymphoproliferative diseases. We evaluated the effects of valganciclovir on oral EBV shedding in a randomized, double-blind, placebo-controlled study. Twenty-six men received oral valganciclovir or daily placebo for 8 weeks, followed by a 2-week "washout period" and then 8 weeks of the alternative treatment. Valganciclovir reduced the proportion of days with EBV detected from 61.3% to 17.8% (relative risk, 0.28; 95% confidence interval [CI], .21-.41; P < .001), and quantity of virus detected by 0.77 logs (95% CI, .62-.91 logs; P < .001). Further investigations into the impact of valganciclovir on EBV-associated diseases are needed.


Assuntos
Antivirais/administração & dosagem , Ganciclovir/análogos & derivados , Mononucleose Infecciosa/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Eliminação de Partículas Virais/efeitos dos fármacos , Adulto , Idoso , Método Duplo-Cego , Ganciclovir/administração & dosagem , Herpesvirus Humano 4/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valganciclovir , Carga Viral/efeitos dos fármacos , Washington , Adulto Jovem
6.
F1000Res ; 4: 1102, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26673611

RESUMO

We previously demonstrated that, while changes in temperature produce dramatic shifts in the time elapsed during Drosophila melanogaster embryogenesis, the relative timing of events within embryogenesis does not change. However, it was unclear if this uniform scaling is an intrinsic property of developing embryos, or if it is specific to thermal fluctuations. To investigate this, here we characterize the embryonic response to changes in oxygen concentration, which also impact developmental rate, using time-lapse imaging, and find it fundamentally different from the temperature response. Most notably, changes in oxygen levels drive developmental heterochrony, with the timing of several morphological processes showing distinct scaling behaviors. Gut formation is severely slowed by decreases in oxygen, while head involution and syncytial development are less impacted than the rest of development, and the order of several developmental landmarks is inverted at different oxygen levels. These data reveal that the uniform scaling seen with changes in temperature is not a trivial consequence of adjusting developmental rate. The developmental rate changes produced by changing oxygen concentrations dwarf those induced by temperature, and greatly impact survival. While extreme temperatures increase early embryo mortality, mild hypoxia increases arrest and death during mid-embryogenesis and mild hyperoxia increases survival over normoxia.

7.
PLoS Genet ; 10(4): e1004293, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24762628

RESUMO

Temperature affects both the timing and outcome of animal development, but the detailed effects of temperature on the progress of early development have been poorly characterized. To determine the impact of temperature on the order and timing of events during Drosophila melanogaster embryogenesis, we used time-lapse imaging to track the progress of embryos from shortly after egg laying through hatching at seven precisely maintained temperatures between 17.5 °C and 32.5 °C. We employed a combination of automated and manual annotation to determine when 36 milestones occurred in each embryo. D. melanogaster embryogenesis takes [Formula: see text]33 hours at 17.5 °C, and accelerates with increasing temperature to a low of 16 hours at 27.5 °C, above which embryogenesis slows slightly. Remarkably, while the total time of embryogenesis varies over two fold, the relative timing of events from cellularization through hatching is constant across temperatures. To further explore the relationship between temperature and embryogenesis, we expanded our analysis to cover ten additional Drosophila species of varying climatic origins. Six of these species, like D. melanogaster, are of tropical origin, and embryogenesis time at different temperatures was similar for them all. D. mojavensis, a sub-tropical fly, develops slower than the tropical species at lower temperatures, while D. virilis, a temperate fly, exhibits slower development at all temperatures. The alpine sister species D. persimilis and D. pseudoobscura develop as rapidly as tropical flies at cooler temperatures, but exhibit diminished acceleration above 22.5 °C and have drastically slowed development by 30 °C. Despite ranging from 13 hours for D. erecta at 30 °C to 46 hours for D. virilis at 17.5 °C, the relative timing of events from cellularization through hatching is constant across all species and temperatures examined here, suggesting the existence of a previously unrecognized timer controlling the progress of embryogenesis that has been tuned by natural selection as each species diverges.


Assuntos
Drosophila melanogaster/genética , Desenvolvimento Embrionário/genética , Seleção Genética/genética , Animais , Temperatura Baixa , Variação Genética/genética , Filogenia , Especificidade da Espécie , Imagem com Lapso de Tempo/métodos
8.
J Clin Virol ; 60(2): 127-32, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24698158

RESUMO

BACKGROUND: Human herpesvirus 8 (HHV-8) replication increases the risk of Kaposi sarcoma (KS). Highly-active antiretroviral therapy (HAART) reduces the incidence of KS, and regimens that contain protease inhibitors (PIs) may be particularly effective. OBJECTIVE: To determine whether PI-based HAART regimens may more effectively inhibit HHV-8 shedding compared to regimens without PIs. STUDY DESIGN: Prospective, observational study of 142 HIV-1 and HHV-8 co-infected men conducted in Seattle, Washington. Quantitative HHV-8 PCR testing was performed on daily swabs of the oropharynx, the primary site of HHV-8 replication. Associations between antiretroviral regimen and detection of HHV-8 DNA in swabs were evaluated using generalized estimating equations. RESULTS: HHV-8 DNA was detected in 3016 (26%) of 11,608 specimens collected. PI-based HAART was associated with a statistically significantly lower frequency of detection (RR 0.2; 95% CI 0.1-0.5) compared to ART-naïve persons, whereas HAART without a PI was not (RR 0.7; 95% CI 0.4-1.3). Compared to ART-naïve persons, there was also a trend toward lower quantities of HHV-8 detected during treatment with HAART regimens that contained a PI. These associations between PIs and measures of HHV-8 shedding could not be attributed to use of nelfinavir, which inhibits HHV-8 replication in vitro, and were independent of CD4 count and HIV plasma viral load (VL). CONCLUSIONS: HAART regimens that contain PIs appear to decrease HHV-8 shedding compared to NNRTIs. Further study of PI-based HAART is warranted to determine the optimal regimens for prevention and treatment of KS.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/isolamento & purificação , Nasofaringe/virologia , Eliminação de Partículas Virais , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/métodos , DNA Viral/análise , DNA Viral/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Carga Viral , Washington , Adulto Jovem
9.
Genome Res ; 22(10): 1907-19, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22730465

RESUMO

Two major transcriptional regulators of Caenorhabditis elegans bodywall muscle (BWM) differentiation, hlh-1 and unc-120, are expressed in muscle where they are known to bind and regulate several well-studied muscle-specific genes. Simultaneously mutating both factors profoundly inhibits formation of contractile BWM. These observations were consistent with a simple network model in which the muscle regulatory factors drive tissue-specific transcription by binding selectively near muscle-specific targets to activate them. We tested this model by measuring the number, identity, and tissue-specificity of functional regulatory targets for each factor. Some joint regulatory targets (218) are BWM-specific and enriched for nearby HLH-1 binding. However, contrary to the simple model, the majority of genes regulated by one or both muscle factors are also expressed significantly in non-BWM tissues. We also mapped global factor occupancy by HLH-1, and created a genetic interaction map that identifies hlh-1 collaborating transcription factors. HLH-1 binding did not predict proximate regulatory action overall, despite enrichment for binding among BWM-specific positive regulatory targets of hlh-1. We conclude that these tissue-specific factors contribute much more broadly to the transcriptional output of muscle tissue than previously thought, offering a partial explanation for widespread HLH-1 occupancy. We also identify a novel regulatory connection between the BWM-specific hlh-1 network and the hlh-8/twist nonstriated muscle network. Finally, our results suggest a molecular basis for synthetic lethality in which hlh-1 and unc-120 mutant phenotypes are mutually buffered by joint additive regulation of essential target genes, with additional buffering suggested via newly identified hlh-1 interacting factors.


Assuntos
Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica , Especificidade de Órgãos/genética , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Sequência Conservada , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Proteínas Musculares , Músculos/metabolismo , Mutação , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Proteínas Nucleares , Motivos de Nucleotídeos , Ligação Proteica , Interferência de RNA , Fatores de Transcrição/genética , Transcriptoma
10.
J Acquir Immune Defic Syndr ; 54(5): 482-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20616743

RESUMO

OBJECTIVE: To determine whether rapidly cleared episodes of herpes simplex virus (HSV) reactivation occur in HIV-infected adults. METHODS: Twenty HSV-2-seropositive, HIV-seropositive adults, including 9 (45%) who were also HSV-1 seropositive, collected oral and anogenital swabs for HSV DNA polymerase chain reaction 4 times a day for 60 days. Samples were positive for HSV if we detected > or =150 copies of HSV DNA/mL of specimen. RESULTS: Median HSV shedding episode duration was 7.5 (range 4-253) hours for oral and 11 (range 4-328) hours for anogenital reactivation. Thirty-five percent of oral and 29% of anogenital reactivations lasted < or =6 hours, and 59% of oral and 53% of anogenital reactivations lasted < or =12 hours. Seven of 9 participants who shed orally and 10 of 15 who shed anogenitally had > or =1 reactivation lasting < or =6 hours. The median maximum level of HSV DNA detected in an episode increased with episode duration for both oral and anogenital episodes. Concurrent oral and anogenital shedding occurred more frequently than expected: oral HSV shedding was detected on 17% of time points with anogenital but 1% of time points without anogenital, shedding (P < 0.001). CONCLUSIONS: Rapidly cleared episodes of oral and anogenital HSV shedding occur in HIV-infected persons, supporting the hypothesis that frequent anogenital mucosal immune activation caused by HSV-2 is present in HIV coinfected persons, potentially contributing to HIV infectiousness.


Assuntos
Canal Anal/virologia , Infecções por HIV/complicações , Herpes Simples/epidemiologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 2/isolamento & purificação , Boca/virologia , Eliminação de Partículas Virais , Adulto , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Herpes Simples/virologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Ativação Viral
11.
Development ; 136(16): 2735-46, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19605496

RESUMO

The C. elegans MS blastomere, born at the 7-cell stage of embryogenesis, generates primarily mesodermal cell types, including pharynx cells, body muscles and coelomocytes. A presumptive null mutation in the T-box factor gene tbx-35, a target of the MED-1 and MED-2 divergent GATA factors, was previously found to result in a profound decrease in the production of MS-derived tissues, although the tbx-35(-) embryonic arrest phenotype was variable. We report here that the NK-2 class homeobox gene ceh-51 is a direct target of TBX-35 and at least one other factor, and that CEH-51 and TBX-35 share functions. Embryos homozygous for a ceh-51 null mutation arrest as larvae with pharynx and muscle defects, although these tissues appear to be specified correctly. Loss of tbx-35 and ceh-51 together results in a synergistic phenotype resembling loss of med-1 and med-2. Overexpression of ceh-51 causes embryonic arrest and generation of ectopic body muscle and coelomocytes. Our data show that TBX-35 and CEH-51 have overlapping function in MS lineage development. As T-box regulators and NK-2 homeodomain factors are both important for heart development in Drosophila and vertebrates, our results suggest that these regulators function in a similar manner in C. elegans to specify a major precursor of mesoderm.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/embriologia , Proteínas de Homeodomínio/metabolismo , Mesoderma/fisiologia , Proteínas com Domínio T/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Blastômeros/fisiologia , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Linhagem da Célula , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Redes Reguladoras de Genes/fisiologia , Proteínas de Homeodomínio/genética , Dados de Sequência Molecular , Fenótipo , Interferência de RNA , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Proteínas com Domínio T/genética , Fatores de Transcrição/genética
12.
Genome Res ; 18(12): 1955-68, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18981268

RESUMO

To learn how well ungapped sequence comparisons of multiple species can predict cis-regulatory elements in Caenorhabditis elegans, we made such predictions across the large, complex ceh-13/lin-39 locus and tested them transgenically. We also examined how prediction quality varied with different genomes and parameters in our comparisons. Specifically, we sequenced approximately 0.5% of the C. brenneri and C. sp. 3 PS1010 genomes, and compared five Caenorhabditis genomes (C. elegans, C. briggsae, C. brenneri, C. remanei, and C. sp. 3 PS1010) to find regulatory elements in 22.8 kb of noncoding sequence from the ceh-13/lin-39 Hox subcluster. We developed the MUSSA program to find ungapped DNA sequences with N-way transitive conservation, applied it to the ceh-13/lin-39 locus, and transgenically assayed 21 regions with both high and low degrees of conservation. This identified 10 functional regulatory elements whose activities matched known ceh-13/lin-39 expression, with 100% specificity and a 77% recovery rate. One element was so well conserved that a similar mouse Hox cluster sequence recapitulated the native nematode expression pattern when tested in worms. Our findings suggest that ungapped sequence comparisons can predict regulatory elements genome-wide.


Assuntos
Sequência de Bases/genética , Genes de Helmintos , Genes Homeobox , Proteínas de Homeodomínio/genética , Sequências Reguladoras de Ácido Nucleico/genética , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Sequência Conservada/genética , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , Proteínas de Homeodomínio/metabolismo , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Transgenes
13.
Trends Cell Biol ; 18(11): 536-44, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18848778

RESUMO

Receptor tyrosine kinase-like orphan receptor (Ror) proteins are a conserved family of tyrosine kinase receptors that function in developmental processes including skeletal and neuronal development, cell movement and cell polarity. Although Ror proteins were originally named because the associated ligand and signaling pathway were unknown, recent studies in multiple species have now established that Ror proteins are Wnt receptors. Depending on the cellular context, Ror proteins can either activate or repress transcription of Wnt target genes and can modulate Wnt signaling by sequestering Wnt ligands. New evidence implicates Ror proteins in planar cell polarity, an alternative Wnt pathway. Here, we review the progress made in understanding these mysterious proteins and, in particular, we focus on their function as Wnt receptors.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , MAP Quinase Quinase 4/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Proteínas Wnt/metabolismo , Animais , Movimento Celular/fisiologia , Polaridade Celular/fisiologia , Humanos , Filogenia , Estrutura Terciária de Proteína , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase
14.
J Infect Dis ; 198(1): 23-30, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18491970

RESUMO

BACKGROUND: Human herpesvirus-8 (HHV-8) replication is critical in the induction and maintenance of Kaposi sarcoma, primary effusion lymphoma, and some cases of Castleman disease. In vitro and observational studies suggest that ganciclovir inhibits HHV-8 replication, but no randomized clinical trials have been conducted. METHODS: A total of 26 men infected with HHV-8 were randomized to receive 8 weeks of valganciclovir administered orally (900 mg once per day) or 8 weeks of placebo administered orally. After a 2-week washout period, participants in each group received the study drug they had not yet taken (either valganciclovir or placebo), for 8 additional weeks. Oral swab samples were collected daily during the study, and HHV-8 and CMV DNA were quantified by real-time PCR. RESULTS: A total of 16 human immunodeficiency virus (HIV)-positive men and 10 HIV-negative men enrolled in and completed the study. Of the 3,439 swab samples that participants had been expected to provide, 3029 (88%) were available for analysis. HHV-8 was detected on 44% of swabs collected from participants who were receiving placebo, compared with 23% of swabs collected from participants who were receiving valganciclovir (relative risk [RR], 0.54 [95% confidence interval {CI}, 0.33-0.90]; P = .02). Valganciclovir reduced oropharyngeal shedding of cytomegalovirus by 80% (RR, 0.20 [95% CI, 0.08-0.48]; P < .001). Shedding of HHV-8 and shedding of cytomegalovirus were independent. Hematologic, renal, or hepatic toxicities were no more common among participants who received the active drug, compared with those who received placebo, though participants who received valganciclovir reported more days of diarrhea. CONCLUSIONS: Valganciclovir administered orally once per day is well tolerated and significantly reduces the frequency and quantity of HHV-8 replication.


Assuntos
Antivirais/uso terapêutico , Ganciclovir/análogos & derivados , Infecções por HIV/complicações , Herpesvirus Humano 8/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Adulto , Idoso , Antivirais/efeitos adversos , Estudos Cross-Over , Método Duplo-Cego , Ganciclovir/efeitos adversos , Ganciclovir/uso terapêutico , Herpesvirus Humano 8/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Orofaringe/virologia , Cooperação do Paciente , Sarcoma de Kaposi/prevenção & controle , Valganciclovir , Eliminação de Partículas Virais/efeitos dos fármacos
15.
Urology ; 69(4): 791-4, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17445683

RESUMO

OBJECTIVES: The molecular mechanisms by which potassium induces urinary bladder hyperactivity are not clear. In the present study, we tested our hypothesis that potassium chloride (KCl)-induced bladder hyperactivity might be mediated through a calcium-sensitizing RhoA-Rho-kinase pathway in an in vivo animal model using urodynamic parameters. METHODS: Two groups of adult male rats (n = 8) were anesthetized, their bladder exteriorized, and a saline-filled Intracath fixed into the bladder dome. This Intracath was connected to a pressure transducer and an infusion pump. Continuous filling cystometrograms were performed by infusing warm saline (0.04 mL/min) to obtain baseline data on each rat. The number of contractions per unit time (intercontractile intervals in seconds), pressure threshold, and peak pressure during micturition were recorded. To create bladder hyperactivity, protamine sulfate (30 mg/mL) followed by KCl (500 mM) was infused intravesically, and a continuous filling cystometrogram was again recorded. Y-27632, a specific RhoA-Rho-kinase inhibitor, was administered either intra-arterially (group 1) or intravesically (group 2) to each rat, and an additional continuous filling cystometrogram was recorded with KCl (500 mM) to observe the effects of Rho-kinase inhibition on bladder contractility. RESULTS: Intravesical KCl infusion after protamine exposure resulted in significantly greater contractions and decreased the intercontractile interval (P <0.05). Y-27632 administration attenuated the effect of KCl on the contractions and intercontractile interval and decreased the mean pressure threshold. CONCLUSIONS: Suppression of KCl-induced bladder contractility by the Rho-kinase inhibitor Y-27632 confirmed the involvement of this novel calcium-sensitizing RhoA-Rho-kinase pathway in mediating these smooth muscle contractions.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Cloreto de Potássio/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Animais , Masculino , Contração Muscular , Ratos , Ratos Sprague-Dawley , Urodinâmica , Quinases Associadas a rho
16.
J Infect Dis ; 195(1): 30-6, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17152006

RESUMO

BACKGROUND: Little is known about the clinical and virologic manifestations of human herpesvirus (HHV)-8 infection in immunocompetent persons in the absence of malignancy. METHODS: A total of 46 human immunodeficiency virus-negative, HHV-8-seropositive men collected saliva daily, and 25 recorded 15 common symptoms daily (gastrointestinal, constitutional, and oropharyngeal) and absences from work or school. Quantitative polymerase chain reaction measured HHV-8 DNA in saliva. RESULTS: Some 44 (96%) of 46 men reported having sex with men (MSM). Of the 44 MSM, 27 (61%) had HHV-8 detected in saliva on > or = 1 day; heterosexual men also shed HHV-8. In analyses restricted to MSM, HHV-8 DNA was detected on 636 (22%) of 2897 days. Among MSM with HHV-8 detected in saliva, the median rate was 20% (range, 1%-100%), with 30% shedding on > 50% of days, and the median quantity was 4.5 log10 copies/mL (range, 2.0-7.3 log10 copies/mL). The quantity of HHV-8 shed was lower in nonwhites (P<.001) and younger participants (P=.03). The frequency of HHV-8 detection and quantity were correlated (r=0.62; P<.001). Symptoms were reported on 10 (9%) of 114 days when HHV-8 was present, compared with 78 (9%) of 830 days without (odds ratio, 0.93 [95% confidence interval, 0.30-2.88]; P=.9). CONCLUSIONS: HHV-8 is detected frequently and intermittently in the saliva of chronically infected immunocompetent MSM, but this infection is asymptomatic.


Assuntos
Herpesvirus Humano 8/fisiologia , Imunocompetência/fisiologia , Boca/virologia , Orofaringe/virologia , Eliminação de Partículas Virais/fisiologia , Adulto , Idoso , Infecções por Herpesviridae/virologia , Homossexualidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Comportamento Sexual
17.
Neurourol Urodyn ; 24(3): 295-300, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15791631

RESUMO

AIMS: Spontaneously hypertensive rats (SHR) exhibit overactive bladder (OAB) symptoms and have an up-regulated calcium sensitizing RhoA/Rho-kinase pathway in their vascular smooth muscle tissues. This study examined the role of RhoA/Rho-kinase pathway in bladder hyperactivity by evaluating the effect of a specific Rho-kinase inhibitor (Y-27632) on SHR bladder function. METHODS: Adult male SHR (n = 9) and their normotensive controls (Wistar-Kyoto; WKY) (n = 8) were anesthetized and the carotid artery cannulated for blood pressure monitoring. A catheter was fixed into the bladder dome and connected to a pressure transducer and an infusion pump. After equilibration, systemic and bladder pressure were recorded. Continuous filling cystometrograms (CMGs) were performed and threshold pressure (TP), peak pressure (PP), and number of voids and non-voiding contractions (NVCs) per unit time recorded. Each SHR then received Y-27632, 10 mumol intra-arterially. After 10 min, CMG was repeated and the same measurements recorded. Bladder tissues were evaluated immunohistochemically (IHC) for RhoA protein expression. RESULTS: SHR exhibited significantly higher number of voids and NVCs than normotensive WKY rats (P < 0.05). In SHR, Y-27362 administration significantly decreased the number of voids (29%, from 0.83 +/- 0.3 to 0.63 +/- 0.17 voids/min) and NVCs (61%, from 1.8 +/- 0.54 to 0.64 +/- 0.167 NVC/min). IHC showed significantly higher RhoA protein expression in SHR bladder tissues. CONCLUSIONS: Overexpression of RhoA may play a role in hypertension-related OAB. Inhibition of Rho-kinase activity with Y-27632 produced a significant suppression of bladder overactivity. Identification of Rho-kinase isoforms that are bladder-tissue specific and their selective inhibitors may help to disassociate the unwanted hypotensive effects of this approach.


Assuntos
Amidas/farmacologia , Inibidores Enzimáticos/farmacologia , Hipertensão/complicações , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Incontinência Urinária/tratamento farmacológico , Animais , Pressão Sanguínea , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Contração Muscular/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/enzimologia , Incontinência Urinária/etiologia , Incontinência Urinária/metabolismo , Urodinâmica/efeitos dos fármacos , Quinases Associadas a rho , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/metabolismo
18.
J Infect Dis ; 190(4): 693-6, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15272395

RESUMO

The effect of highly active antiretroviral therapy (HAART) on control of herpes simplex virus (HSV) in human immunodeficiency virus (HIV) type 1-infected subjects is not known. Among 28 HAART-treated and 49 untreated subjects with HIV-1 and HSV-2 infections, mucosal HSV shedding (median, 18% and 29% of days positive for HSV DNA, respectively; P=.08) and HSV DNA level (median, 56,250 and 50,000 copies/mL, respectively; P=.20) were similar. Treated subjects reported significantly fewer days with HSV lesions, compared with untreated subjects (2.8% vs. 11.3% of days, respectively; P=.001). Thus, mucosal HSV shedding and HSV-2 reactivation were still frequent among treated subjects, even though HAART was associated with fewer days with HSV lesions.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1 , HIV-2 , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 2/isolamento & purificação , Simplexvirus/isolamento & purificação , Adulto , DNA Viral/análise , Feminino , Genitália/virologia , Infecções por HIV/complicações , Infecções por HIV/virologia , Herpes Simples/complicações , Herpes Simples/patologia , Herpesvirus Humano 2/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/virologia , Mucosa/virologia , Simplexvirus/genética , Eliminação de Partículas Virais
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