Zhang Peng, Liu Linghua, Yao Lei, Song Xiaoxue
Department of Intensive Care Medicine, Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.
Department of Respiratory and Critical Care Medicine, Shaanxi Provincial People's Hospital, Xi'an, China.
Int J Stem Cells. 2021 May 30;14(2):229-239. doi: 10.15283/ijsc20136.
Implantation of bone marrow-derived mesenchymal stem cells (BMSCs) has been recognized as an effective therapy for attenuating acute lung injury (ALI). This study aims to discover microRNA (miRNA)-mediated improvement of BMSCs-based therapeutic effects.
Mice were treated with lipopolysaccharide (LPS) for induction of ALI. BMSCs with lentivirus- mediated expression of miR-23b-3p or fibroblast growth factor 2 (FGF2) were intratracheally injected into the mice with ALI. The expressions of miR-23b-3p, FGF2, Occludin, and surfactant protein C (SPC) in lung tissues were analyzed by immunoblot or quantitative reverse transcription polymerase chain reaction. Histopathological changes in lung tissues were observed via hematoxylin-eosin staining. Lung edema was assessed by the ratio of lung wet weight/body weight (LWW/BW). The levels of interleukin (IL)-1, IL-6, IL-4, and IL-8 in bronchoalveolar lavage fluid (BALF) were assessed by ELISA. LPS injection downregulated the expressions of miR-23b-3p, SPC and Occludin in the lung tissues, increased the LWW/BW ratio and aggravated histopathological abnormalities, while upregulating IL-1, IL-6, IL-4, and IL-8 in the BALF. Upregulated miR-23b-3p counteracted LPS-induced effects, whereas downregulated miR-23b-3p intensified LPS-induced effects. FGF2, which was downregulated by miR-23b-3p upregulation, was a target gene of miR-23b-3p. Overexpressing FGF2 downregulated the expressions of miR-23b-3p, SPC and Occludin, increased the LWW/BW ratio and aggravated histopathological abnormalities, while upregulating IL-1, IL-6, IL-4, and IL-8, and it offset miR-23b-3p upregulation-caused effects on the ALI mice.
Overexpression of miR-23b-3p in BMSCs strengthened BMSC-mediated protection against LPS-induced mouse acute lung injury via targeting FGF2.
骨髓间充质干细胞（BMSC）移植已被公认为是减轻急性肺损伤（ALI）的有效治疗方法。本研究旨在探索微小RNA（miRNA）介导的基于BMSC的治疗效果改善。
用脂多糖（LPS）处理小鼠以诱导ALI。将慢病毒介导表达miR-23b-3p或成纤维细胞生长因子2（FGF2）的BMSC经气管内注射到ALI小鼠体内。通过免疫印迹或定量逆转录聚合酶链反应分析肺组织中miR-23b-3p、FGF2、闭合蛋白和表面活性蛋白C（SPC）的表达。通过苏木精-伊红染色观察肺组织的组织病理学变化。通过肺湿重/体重比（LWW/BW）评估肺水肿。通过酶联免疫吸附测定法评估支气管肺泡灌洗液（BALF）中白细胞介素（IL）-1、IL-6、IL-4和IL-8的水平。注射LPS下调了肺组织中miR-23b-3p、SPC和闭合蛋白的表达，增加了LWW/BW比值并加重了组织病理学异常，同时上调了BALF中IL-1、IL-6、IL-4和IL-8的水平。上调miR-23b-3p可抵消LPS诱导的效应，而下调miR-23b-3p则增强LPS诱导的效应。miR-23b-3p上调使其表达下调的FGF2是miR-23b-3p的靶基因。过表达FGF2下调了miR-23b-3p、SPC和闭合蛋白的表达，增加了LWW/BW比值并加重了组织病理学异常，同时上调了IL-1、IL-6、IL-4和IL-8，并且抵消了miR-23b-3p上调对ALI小鼠产生的效应。
BMSC中miR-23b-3p的过表达通过靶向FGF2增强了BMSC介导的对LPS诱导的小鼠急性肺损伤的保护作用。
