Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China (mainland).
Department of Intensive Care Unit, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, China (mainland).
Med Sci Monit. 2020 Mar 23;26:e920793. doi: 10.12659/MSM.920793.
BACKGROUND Chronic obstructive pulmonary disease (COPD), a general airway disease, is featured by progressive and chronic immunoreaction in the lung. Increasing evidences have showed that cigarette smoking is the main reason in the COPD progression, and human pulmonary microvascular endothelial cell (HPMEC) apoptosis often be observed in COPD, while its pathogenesis is not yet fully described. Upregulation of long noncoding RNA (lncRNA) maternally expressed gene 3 (MEG3) was observed in COPD patients, but the specific mechanism of lncRNA MEG3 in COPD remains unknown. The objective of this research was to explore the role of lncRNA MEG3 in cigarette smoke extract (CSE)-induced HPMECs. MATERIAL AND METHODS HPMECs were induced by a series of concentrations of CSE (0%, 0.1%, 1%, and 10%). Then cell apoptosis was analyzed by flow cytometry. Cell apoptosis related proteins were tested using western blot assay. Finally, we applied knockdown and over-expression system to explore the lncRNA MEG3 functions in CSE-induced HPMECs. RESULTS Our results indicated that various concentrations of CSE (0%, 0.1%, 1%, and 10%) significantly promoted cell apoptosis, augmented caspase-3 activity, upregulated Bax expression, decreased Bcl-2 expression, and enhanced lncRNA MEG3 level in HPMECs. LncRNA MEG3-plasmid transfection resulted in the upregulation of lncRNA MEG3, more apoptotic HPMECs, and higher caspase-3 activity. While lncRNA MEG3 knockdown presented the opposite effects. Further investigation suggested that all the effects of CSE treatment on HPMECs were markedly reversed by lncRNA MEG3-shRNA (short hairpin RNA). CONCLUSIONS Our study illustrated a protective effect of lncRNA MEG3-shRNA on CSE-induced HPMECs, indicting lncRNA MEG3 can be a new therapeutic approach for COPD treatment.
慢性阻塞性肺疾病（COPD）是一种常见的气道疾病，其特征是肺部进行性和慢性免疫反应。越来越多的证据表明，吸烟是 COPD 进展的主要原因，COPD 患者常观察到人类肺微血管内皮细胞（HPMEC）凋亡，但其发病机制尚未完全描述。在 COPD 患者中观察到长链非编码 RNA（lncRNA）母系表达基因 3（MEG3）的上调，但 lncRNA MEG3 在 COPD 中的具体机制尚不清楚。本研究旨在探讨 lncRNA MEG3 在香烟烟雾提取物（CSE）诱导的 HPMEC 中的作用。
用一系列浓度的 CSE（0%、0.1%、1%和 10%）诱导 HPMEC。然后用流式细胞术分析细胞凋亡。用 Western blot 检测细胞凋亡相关蛋白。最后，我们应用敲低和过表达系统来探讨 lncRNA MEG3 在 CSE 诱导的 HPMEC 中的作用。
结果表明，不同浓度的 CSE（0%、0.1%、1%和 10%）显著促进 HPMEC 细胞凋亡，增加 caspase-3 活性，上调 Bax 表达，下调 Bcl-2 表达，上调 lncRNA MEG3 水平。lncRNA MEG3-质粒转染导致 lncRNA MEG3 上调，更多的 HPMEC 细胞凋亡，以及更高的 caspase-3 活性。而 lncRNA MEG3 敲低则呈现相反的效果。进一步的研究表明，CSE 处理对 HPMEC 的所有作用均明显被 lncRNA MEG3-shRNA（短发夹 RNA）逆转。
本研究表明 lncRNA MEG3-shRNA 对 CSE 诱导的 HPMEC 具有保护作用，表明 lncRNA MEG3 可以成为 COPD 治疗的新方法。
