MicroRNA dysregulation in lung injury: the role of the miR-26a/EphA2 axis in regulation of endothelial permeability
MicroRNA dysregulation in lung injury: the role of the miR-26a/EphA2 axis in regulation of endothelial permeability
复制标题
DOI：
10.1152/ajplung.00073.2017
复制
发表时间：
2018-10-01
影响因子：
4.9
通讯作者：
Nozik-Grayck, Eva
中科院分区：
文献类型：
--
作者：
Good, Ryan J.;Hernandez-Lagunas, Laura;Nozik-Grayck, Eva
微小RNA（miRNAs）是一种非编码RNA，在许多疾病中调节基因表达，但miRNAs在肺损伤病理生理学中的作用尚不清楚。我们假设miRNA表达的失调驱动了与肺损伤发展有关的关键基因的变化。为了验证我们的假设，我们利用了一个模型，肺内博莱霉素（0.1 U）给药后早期诱导的肺损伤。用博来霉素或PBS处理野生型小鼠，并在第4或7天收集肺。通过miRNA阵列确定肺miRNA谱，并通过定量PCR和流式细胞术确认。肺miR-26 a在博来霉素损伤后7天显著降低，并且基于预测的基因靶点的富集，其被鉴定为细胞粘附的推定调节剂，包括在改变的屏障功能中重要的基因靶点EphA 2、KDR和ROCK 1。肺EphA 2 mRNA和蛋白在博莱霉素损伤的肺中增加。我们进一步使用人肺微血管内皮细胞（HMVEC-L）在体外探索miR-26 a/EphA 2轴。用miR-26 a模拟物和抑制剂转染细胞，并测量基因靶标的表达和渗透性。miR-26 a调节EphA 2的表达，但不调节KDR或ROCK 1的表达。此外，miR-26 a抑制增加了HMVEC-L的渗透性，并且由于miR-26 a而破坏的屏障完整性被EphA 2敲低所阻断，如VE-钙粘蛋白染色所示。我们的数据表明，miR-26 a是肺内皮中EphA 2表达的重要表观遗传调节因子。因此，miR-26 a可能通过减轻EphA 2介导的通透性变化而代表肺损伤中的新治疗靶点。
MicroRNAs (miRNAs) are noncoding RNAs that regulate gene expression in many diseases, although the contribution of miRNAs to the pathophysiology of lung injury remains obscure. We hypothesized that dysregulation of miRNA expression drives the changes in key genes implicated in the development of lung injury. To test our hypothesis, we utilized a model of lung injury induced early after administration of intratracheal bleomycin (0.1 U). Wild-type mice were treated with bleomycin or PBS, and lungs were collected at 4 or 7 days. A profile of lung miRNA was determined by miRNA array and confirmed by quantitative PCR and flow cytometry. Lung miR-26a was significantly decreased 7 days after bleomycin injury, and, on the basis of enrichment of predicted gene targets, it was identified as a putative regulator of cell adhesion, including the gene targets EphA2, KDR, and ROCK1, important in altered barrier function. Lung EphA2 mRNA, and protein increased in the bleomycin-injured lung. We further explored the miR-26a/EphA2 axis in vitro using human lung microvascular endothelial cells (HMVEC-L). Cells were transfected with miR-26a mimic and inhibitor, and expression of gene targets and permeability was measured. miR-26a regulated expression of EphA2 but not KDR or ROCK1. Additionally, miR-26a inhibition increased HMVEC-L permeability, and the disrupted barrier integrity due to miR-26a was blocked by EphA2 knockdown, shown by VE-cadherin staining. Our data suggest that miR-26a is an important epigenetic regulator of EphA2 expression in the pulmonary endothelium. As such, miR-26a may represent a novel therapeutic target in lung injury by mitigating EphA2-mediated changes in permeability.