RESUMO
Background: Previous studies have revealed the important role of alveolar macrophages (AMs) in the pathogenesis of acute respiratory distress syndrome (ARDS) and potential anti-inflammatory properties of lincRNA-p21. This study aims to study the association between lincRNA-p21 and active AMs to understand the molecular mechanisms of AMs-mediated inflammatory responses in ARDS.Methods: This study was mainly investigated in mice with the intratracheal instillation of lipopolysaccharide (LPS) or LPS-treated AMs. The expression of lincRNA-p21 and classical macrophage markers, IL-12ß and iNOS, was detected by quantitative RT-PCR, while NF-κB p65 translocation was measured by western blotting analysis. And, NF-κB activity was analyzed through luciferase report assays. Gain- and loss-of-function studies were also performed for further investigations.Results: Elevated lincRNA-p21 levels were observed in both LPS-induced ARDS mice and LPS-treated AMs, with upregulated expression of IL-12ß and iNOS, namely M1 activation, and p65 nuclear translocation. Further in vitro studies showed that LPS-induced M1 activation could be counteracted by both lincRNA-p21 inhibition and inhibited NF-κB activation. Moreover, both p65 nuclear translocation and NF-κB activity were promoted by lincRNA-p21 overexpression, while lincRNA-p21 inhibition showed a negative effect on LPS-induced p65 nuclear translocation and increase of NF-κB activity. Additionally, LPS-induced lung injuries could be attenuated by lincRNA-p21 inhibition in vivo.Conclusion: This study revealed elevated lincRNA-p21 levels in LPS-induced ARDS and investigated the potential role of lincRNA-p21 in LPS-induced pro-inflammatory response via NF-κB/p65 mediated pathways, suggesting the potential application of lincRNA-p21 for ADRS therapy.
Assuntos
Ativação de Macrófagos/genética , Macrófagos Alveolares/metabolismo , NF-kappa B/genética , RNA Longo não Codificante/genética , Síndrome do Desconforto Respiratório/genética , Quinases Ativadas por p21/genética , Animais , Regulação da Expressão Gênica/genética , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Lesão Pulmonar/genética , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/genética , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Fator de Transcrição RelA/genéticaRESUMO
AIMS: To explore the role of long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) in the cell proliferation of airway smooth muscle cells (ASMCs) in asthma. MATERIALS AND METHODS: An asthma rat model was established by ovalbumin sensitization and challenge. The expression of GAS5, miR-10a and BDNF mRNA and protein was determined with qRT-PCR and western blot, separately. The targeting relationship between GAS5 and miR-10a was examined with RNA immunoprecipitation and RNA pull-down assay; the interaction between miR-10a and BDNF was evaluated by luciferase reporter assay. Cell Proliferation Assay (MTS) was used for ASMC proliferation detection. Knock-down of GAS5 was performed in asthmatic rats to determine the effects of GAS5 in vivo. KEY FINDINGS: Compared with control group, the inspiratory resistance and expiratory resistance were increased in asthma group; and the expression of GAS5, miR-10a and BDNF was higher, lower and higher, respectively. The expression of GAS5 and miR-10a was elevated and repressed, respectively, by platelet-derived growth factor-BB (PDGF-BB). GAS5 functioned as a bait of miR-10a. GAS5 regulates BDNF expression through miR-10a. PDGF-BB promotes the cell proliferation of ASMCs through miR-10a/BDNF. Knock-down of GAS5 significantly decreased airway hyperresponsiveness in asthmatic rats. SIGNIFICANCE: The lncRNA GAS5/miR-10a/BDNF regulatory axis played an important role in promoting ASMCs proliferation, thus contributing to asthma.
Assuntos
Asma/patologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células , MicroRNAs/genética , Miócitos de Músculo Liso/patologia , RNA Longo não Codificante/genética , Sistema Respiratório/patologia , Animais , Apoptose , Asma/genética , Asma/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Células Cultivadas , Regulação Neoplásica da Expressão Gênica , Miócitos de Músculo Liso/metabolismo , Ratos , Sistema Respiratório/metabolismo , Transdução de SinaisRESUMO
OBJECTIVE: The mechanism of Schisandrin B on the proliferation and migration of airway smooth muscle cells (ASMCs) in asthmatic rats was explored. METHODS: SD rats were divided into three groups: control (group 1), model (group 2) and model + Schisandrin B (group 3). miR-150 and lncRNA BCYRN1 levels were measured by qRT-PCR. The combination of BCYRN1 and miR-150 was detected by RNA pull down. ASMCs' viability/proliferation/migration were examined by WST-1 assay and 24-well Transwell system. RESULTS: Schisandrin B up-regulated miR-150 expression and down-regulated BCYRN1 expression in sensitized rats. Schisandrin B reversed the expression of miR-150 and BCYRN1 in MV-treated ASMCs. In addition, Schisandrin B inhibited the viability, proliferation and migration of MV-induced ASMCs. We also found miR-150 inhibited BCYRN1 expression which was proved by experiments using ASMCs transfected with miR-150 inhibitor. CONCLUSION: Schisandrin B increased miR-150 expression and decreased BCYRN1, and BCYRN1 expression was inhibited by miR-150, which indicated that Schisandrin B could regulate BCYRN1 through miR-150.