RESUMO
BACKGROUND: Asthma is one of the most frequent and serious diseases worldwide. Inflammation has been reported to correlate with airway remodeling, which is critical for the progression of asthma. Better understanding of novel molecules modulating asthma and the underlying mechanism will benefit explorations of new treatments. Method: To explore the role of miR-200a and miR-200b in asthma, miR-200a mimics/inhibitor and miR-200b mimics/inhibitor were employed in A549 cells, respectively. Expression levels of inflammatory cytokines, including TNF-α, IL-4, IL-5, IL-13 and IL-1ß, were measured by quantitative real time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). A dual luciferase reporter assay was performed to identify whether miR-200a/200b directly bound to Orosomucoid 1-like 3 (ORMDL3). ERK, p-ERK and MMP-9, involved in downstream pathways of ORMDL3, were detected using qRT-PCR and western blotting. Results: MiR-200a/200b silencing significantly increased the expression of inflammatory cytokines, including TNF-α, IL-4, IL-5, IL-13 and IL-1ß, in A549 cells. ORMDL3 was the target gene of miR-200a/200b, with high expression levels in miR-200a inhibitor and miR-200b inhibitor groups. MiR-200a and miR-200b played synergistic roles in the regulation of the inflammatory effect in A549 cells. Expression levels of p-ERK and MMP-9 were significantly increased in miR-200a inhibitor and miR-200b inhibitor groups and were rescued by ERK inhibitor and MMP-9 inhibitor, respectively. Conclusion: These findings suggest that miR-200a and miR-200b are required to regulate asthma inflammation. Reduction in miR-200a/200b promotes the development of asthma inflammation by targeting ORMDL3 to activate the ERK/MMP-9 pathway. Therefore, elevating miR-200a and miR-200b and decreasing ORMDL3 might be potential strategies for inhibition of the asthma process.
Assuntos
Inflamação/genética , Sistema de Sinalização das MAP Quinases/genética , Metaloproteinase 9 da Matriz/genética , Proteínas de Membrana/genética , MicroRNAs/genética , Transdução de Sinais/genética , Células A549 , Remodelação das Vias Aéreas/genética , Asma/genética , Linhagem Celular Tumoral , Citocinas/genética , Expressão Gênica/genética , HumanosRESUMO
The objective of the present study was to explore the function and mechanism of long noncoding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) in pulmonary fibrosis (PF) progression. HPAEpic cells and A549 cells were exposed to hypoxic conditions to establish an in vitro model. Cell apoptosis was detected by TUNEL assay, and inflammatory cytokine levels were detected by ELISA. Gene and protein expression levels were identified by qRT-PCR and Western blot assays, respectively. The interaction among NEAT1, miR-29a, and NFATc3 was identified by dual-luciferase reporter and RNA pull-down assays. In hypoxia-treated cells, hypoxia markers (HIF-1α and HIF-2α), cytokines (TNF-α, IL-1ß, and IL-6) and fibrotic markers (α-SMA, collagen I and collagen III) were significantly enhanced. Consistently, the expression levels of NEAT1 and NFATc3 were increased, but miR-29a was decreased in hypoxia-stimulated cells. Knockdown of NEAT1 significantly decreased cell apoptosis and the releases of TNF-α, IL-1ß, and IL-6 as well as reduced the levels of α-SMA, collagen I, and collagen III. Moreover, NEAT1 positively regulated NFATc3 expression by directly targeting miR-29a. Functional experiments showed that the anti-apoptotic, anti-inflammatory, and anti-fibrotic effects mediated by NETA1 silencing were impeded by miR-29a inhibition or NFATc3 overexpression in hypoxia-stimulated HPAEpic and A549 cells. Collectively, these data demonstrated that NEAT1 knockdown inhibited hypoxia-induced cell apoptosis, inflammation, and fibrosis by targeting the miR-29a/NFATc3 axis in PF, suggesting that NEAT1 might be a potential therapeutic target for relieving PF progression.
Assuntos
MicroRNAs , RNA Longo não Codificante , Células Epiteliais Alveolares/metabolismo , Apoptose/genética , Fibrose , Humanos , Hipóxia/genética , Inflamação/genética , Interleucina-6/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Fatores de Transcrição NFATC , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fator de Necrose Tumoral alfaRESUMO
We characterized the expression profile of angiogenesis-related genes (ARG) and matrix metalloproteinase (MMP) genes in preterm infants, with and without bronchopulmonary dysplasia (BPD). We reanalyzed a gene expression dataset for preterm infants from the Gene Expression Omnibus database using the Gene-Cloud of Biotechnology Information platform. A total of 1,652 genes were differentially (1.2-fold change) expressed: 811 were highly expressed in infants with BPD, and 841 were highly expressed in those without BPD. Twenty-eight and 11 ARGs were upregulated in infants with and without BPD, respectively. Among 27 detected MMPs and TIMPs, MMP8, MMP9, MMP25, TIMP2 and TIMP3 were differently expressed. Levels of THBS1, MMP8, MMP9, MMP25, TIMP2 and TIMP3 increased as severity of BPD and retinopathy of prematurity (ROP) increased, whereas ETS1, LEF1 and SPOCK2 exhibited the opposite trend. Expression of ETS1 and LEF1 had a fitting rate of R2 = 0.849 and P < 0.001. ELISAs showed a positive correlation between THBS1 and CD36 (receptor of THBS1) levels in serum samples from preterm infants. Our study indicates that the upregulation of THBS1 and downregulation of ETS1, LEF1 promotes BPD in preterm infants by disrupting blood vessel formation rather than by dysregulation of MMPs and TIMPs.