脐带间充质干细胞外泌体对急性肺损伤幼鼠的保护作用研究

The Protective Effect of Umbilical Cord Mesenchymal Stem Cell Exosomes on Acute Lung Injury in Neonatal Rats

为探索人脐带间充质干细胞外泌体(hUCMSC-Exo)对急性肺损伤(ALI)幼鼠模型的保护作用机制,为治疗新生儿呼吸窘迫综合征(NARDS)研究新的方法,本研究构建了一种基于新生幼鼠的ALI的动物模型。经hUCMSC-Exo治疗后发现,新生幼鼠的死亡率明显降低,新生幼鼠的体重下降趋势也得到缓解。收集各组幼鼠的肺组织提取总蛋白、RNA和匀浆,用蛋白质免疫印记(Western blot)检测p-NF-κB、IL-6、Occludin、Cludin 5、β-Catenin、Cyclin D1的蛋白表达水平;用逆转录实时荧光定量聚合酶链式反应(RT-qPCR)检测TNF-α、IL-1β、IL-6、IL-4、IL-10、IL-13的mRNA表达水平;用酶联免疫吸附剂测定(ELISA)检测肺组织中TNF-α、IL-6、IL-10细胞因子的浓度。肺组织病理切片结果显示,外泌体治疗后的炎症细胞浸润、肺泡间隔增厚、肺泡出血及水肿程度均有所减弱。研究结果说明,脂多糖(LPS)可以有效诱导新生幼鼠产生肺部炎症反应,从而引起ALI,而外泌体的治疗减轻了ALI的程度。本研究结果为NARDS治疗提供了新的策略。

The aim of this study is to explore the protective mechanism of human umbilical cord mesenchymal stem cell exosomes(hUCMSC-Exo)on acute lung injury(ALI)in neonatal rats,and to provide a new method for the treatment of neonatal respiratory distress syndrome(NARDS),This study constructed an animal model of ALI based on neonatal rats.After treatment with hUCMSC-Exo,it was found that the mortality rate of neonatal rats was significantly improved,and the trend of weight loss in neonatal rats was also alleviated.Lung tissue samples were collected from each group of neonatal rats to extract total protein,RNA,and homogenate.Western blot was used to detect the protein expression levels of p-NF-κB,IL-6,Occludin,Cludin 5,β-Catenin,and Cyclin D1;the mRNA expression levels of TNF-α,IL-1β,IL-6,IL-4,IL-10 and IL-13 were detected by RT-qPCR;enzyme-linked immunosorbent assay(ELISA)was used to detect the concentrations of TNF-α,IL-6,and IL-10 in lung tissue.The results of pathological sections of lung tissue showed that the infiltration of inflammatory cells,thickening of alveolar septa,pulmonary hemorrhage,and edema were all reduced after treatment with exosomes.The research results indicate that LPS can effectively induce pulmonary inflammation in neonatal rats,leading to acute lung injury,the treatment with exosomes alleviated the degree of ALI.The results of this study can provide new strategies for the treatment of NARDS.