Department of Medical Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China.
Department of Medical Intensive Care Unit, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China.
Biochem Biophys Res Commun. 2020 Jul 23;528(2):311-317. doi: 10.1016/j.bbrc.2020.05.042. Epub 2020 May 14.
Acute respiratory distress syndrome (ARDS) becomes a serious challenge in critical care medicine due to the lack of effective therapy. As the damage of alveolar epithelium is a characteristic feature of ARDS, inducing mesenchymal stem cells (MSCs) to differentiate into alveolar epithelial cells turns out to be a promising therapy for ARDS, but the differentiation efficiency is yet to be improved. The study aimed to investigate the effect of overexpressing FoxM1 on MSCs' differentiation into alveolar epithelial cells.
MSCs were isolated from mouse bone marrow, followed by transfected with lentivirus carrying the FoxM1 plasmid. Small airway epithelial cell growth medium was used as a culture system for inducing MSCs' differentiation into alveolar epithelial cells. Differentiation efficiency was assessed by detecting the expression levels of specific markers of alveolar epithelial cells mainly using quantitative reverse-transcription polymerase chain reaction and Western blot. To examine whether Wnt/β-catenin signalling was involved in the regulation mechanism, a specific inhibitor of the pathway XAV-939 was used and nuclear and cytoplasmic proteins were also analysed respectively. Co-immunoprecipitation was performed to examine the potential interaction between FoxM1 and β-catenin.
Overexpressing FoxM1 statistically significantly increased the expression levels of specific markers of type II alveolar epithelial cells prosurfactant protein C and surfactant protein B, which was partially reversed by XAV-939 treatment, while the expression levels of specific marker of type I alveolar epithelial cells aquaporin 5 did not change significantly. Overexpressing FoxM1 also increased the nuclear translocation of β-catenin and its transcriptional activity. A direct interaction between FoxM1 and β-catenin was found in co-immunoprecipitation assay.
Overexpression of FoxM1 could improve the efficiency of MSCs' differentiation into type II alveolar epithelial cells partly by activating Wnt/β-catenin signalling.
急性呼吸窘迫综合征（ARDS）由于缺乏有效治疗方法，成为重症医学领域的严峻挑战。肺泡上皮损伤是 ARDS 的特征性表现，因此诱导间充质干细胞（MSCs）向肺泡上皮细胞分化成为一种有前景的 ARDS 治疗方法，但分化效率有待提高。本研究旨在探讨过表达 FoxM1 对 MSCs 向肺泡上皮细胞分化的影响。
从小鼠骨髓中分离 MSCs，然后用携带 FoxM1 质粒的慢病毒转染。用小气道上皮细胞生长培养基作为诱导 MSCs 向肺泡上皮细胞分化的培养系统。主要通过定量逆转录聚合酶链反应和 Western blot 检测肺泡上皮细胞特异性标志物的表达水平来评估分化效率。为了研究 Wnt/β-catenin 信号通路是否参与调控机制，使用该通路的特异性抑制剂 XAV-939，并分别分析核蛋白和胞质蛋白。通过共免疫沉淀实验检测 FoxM1 和 β-catenin 之间的潜在相互作用。
过表达 FoxM1 可统计学显著增加Ⅱ型肺泡上皮细胞特异性标志物 prosurfactant protein C 和 surfactant protein B 的表达水平，XAV-939 处理部分逆转了这一结果，而Ⅰ型肺泡上皮细胞特异性标志物 aquaporin 5 的表达水平无明显变化。过表达 FoxM1 还增加了β-catenin 的核转位及其转录活性。在共免疫沉淀实验中发现 FoxM1 和 β-catenin 之间存在直接相互作用。
过表达 FoxM1 可通过激活 Wnt/β-catenin 信号通路，部分提高 MSCs 向Ⅱ型肺泡上皮细胞的分化效率。
