RESUMO
MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression and are implicated in the etiology of several neuropsychiatric disorders, including substance use disorders (SUDs). Using in silico genome-wide sequence analyses, we identified miR-495 as a miRNA whose predicted targets are significantly enriched in the Knowledgebase for Addiction Related Genes (ARG) database (KARG; http://karg.cbi.pku.edu.cn). This small non-coding RNA is also highly expressed within the nucleus accumbens (NAc), a pivotal brain region underlying reward and motivation. Using luciferase reporter assays, we found that miR-495 directly targeted the 3'UTRs of Bdnf, Camk2a and Arc. Furthermore, we measured miR-495 expression in response to acute cocaine in mice and found that it is downregulated rapidly and selectively in the NAc, along with concomitant increases in ARG expression. Lentiviral-mediated miR-495 overexpression in the NAc shell (NAcsh) not only reversed these cocaine-induced effects but also downregulated multiple ARG mRNAs in specific SUD-related biological pathways, including those that regulate synaptic plasticity. miR-495 expression was also downregulated in the NAcsh of rats following cocaine self-administration. Most importantly, we found that NAcsh miR-495 overexpression suppressed the motivation to self-administer and seek cocaine across progressive ratio, extinction and reinstatement testing, but had no effect on food reinforcement, suggesting that miR-495 selectively affects addiction-related behaviors. Overall, our in silico search for post-transcriptional regulators identified miR-495 as a novel regulator of multiple ARGs that have a role in modulating motivation for cocaine.
Assuntos
Transtornos Relacionados ao Uso de Cocaína/genética , MicroRNAs/genética , MicroRNAs/fisiologia , Regiões 3' não Traduzidas , Animais , Comportamento Aditivo/genética , Cocaína/genética , Cocaína/metabolismo , Simulação por Computador , Condicionamento Operante/efeitos dos fármacos , Extinção Psicológica/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Motivação/genética , Plasticidade Neuronal/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiopatologia , Ratos , Ratos Sprague-Dawley , Reforço Psicológico , AutoadministraçãoRESUMO
Human papillomaviruses (HPVs) are involved in the pathogenesis of cancer of the cervix (CaCx). MicroRNA (miRNA) expression analysis using Ambion (Austin, TX, USA) arrays showed that three miRNAs were overexpressed and 24 underexpressed in cervical cell lines containing integrated HPV-16 DNA compared to the normal cervix. Furthermore, nine miRNAs were overexpressed and one underexpressed in integrated HPV-16 cell lines compared to the HPV-negative CaCx cell line C-33A. Based on microarray and/or quantitative real-time PCR and northern blot analyses, microRNA-218 (miR-218) was specifically underexpressed in HPV-positive cell lines, cervical lesions and cancer tissues containing HPV-16 DNA compared to both C-33A and the normal cervix. Expression of the E6 oncogene of high-risk HPV-16, but not that of low-risk HPV-6, reduced miR-218 expression, and conversely, RNA interference of E6/E7 oncogenes in an HPV-16-positive cell line increased miR-218 expression. We also demonstrate that the epithelial cell-specific marker LAMB3 is a target of miR-218. We also show that LAMB3 expression is increased in the presence of the HPV-16 E6 oncogene and this effect is mediated through miR-218. These findings may contribute to a better understanding of the molecular mechanisms involved in cervical carcinogenesis.
Assuntos
Transformação Celular Viral , Regulação Neoplásica da Expressão Gênica , Papillomavirus Humano 16/metabolismo , MicroRNAs/biossíntese , Infecções por Papillomavirus/metabolismo , RNA Neoplásico/biossíntese , Neoplasias do Colo do Útero/metabolismo , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/genética , Transformação Celular Viral/genética , Feminino , Perfilação da Expressão Gênica , Células HeLa , Papillomavirus Humano 16/genética , Papillomavirus Humano 6/genética , Papillomavirus Humano 6/metabolismo , Humanos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Oncogênicas Virais/antagonistas & inibidores , Proteínas Oncogênicas Virais/biossíntese , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/genética , RNA Neoplásico/genética , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , CalininaAssuntos
Anestesia Geral , Anestesia Local , Hérnia Inguinal/cirurgia , Anilidas , Humanos , Masculino , Morfina , Ácidos PipecólicosRESUMO
The salient features of currently available bronchus blockers, single and double lumen endobronchial tubes are briefly discussed (AU)
