吉林大学学报(医学版) ›› 2020, Vol. 46 ›› Issue (6): 1155-1161.doi: 10.13481/j.1671-587x.20200608

• 基础研究 • 上一篇    下一篇

FOXO1对急性肺损伤小鼠肺泡上皮钠通道的调控作用及其机制

何婧,王导新,邓旺()   

  1. 重庆医科大学附属第二医院呼吸与危重症学科,重庆 400010
  • 收稿日期:2020-02-15 出版日期:2020-11-28 发布日期:2022-08-24
  • 通讯作者: 邓旺 E-mail:bsb_dw@163.com
  • 作者简介:何 婧(1987-),女,重庆市人,主治医师,医学博士,主要从事呼吸危重症基础和临床方面的研究。
  • 基金资助:
    国家自然科学基金资助课题(81600060)

Regulatory effect of FOXO1 on alveolar epithelial sodium channel in acute lung injury mice and its mechanism

Jing HE,Daoxin WANG,Wang DENG()   

  1. Department of Respiratory Medicine,Second Affiliated Hospital,Chongqing Medical University,Chongqing 400010,China
  • Received:2020-02-15 Online:2020-11-28 Published:2022-08-24
  • Contact: Wang DENG E-mail:bsb_dw@163.com

摘要: 目的

探讨叉头框蛋白O1(FOXO1) 对脂多糖(LPS)诱导的急性肺损伤小鼠肺泡上皮钠通道(ENaC)的调控作用,并阐明其可能的作用机制。

方法

20只C57BL/6J小鼠随机分为对照组和LPS组,每组10只。经相应处理后分别留取标本,HE染色观察2组小鼠肺组织病理形态表现,RT-PCR和Western blotting法检测2组小鼠肺组织中α亚基ΕΝαC(αENaC)mRNA表达水平及磷酸化FOXO1(pFOXO1)表达水平。培养肺泡上皮A549细胞,分别进行基因干预,使A549细胞过表达或沉默FOXO1基因,RT-PCR法检测αENaC mRNA表达水平。A549细胞分为对照组、胰岛素组、胰岛素+PI3K抑制剂组和胰岛素+AKT抑制剂组,分别干预后收集细胞,Western blotting法检测各组A549细胞中pFOXO1(Ser256)蛋白表达水平,RT-PCR法检测各组A549细胞中αENaC mRNA表达水平,免疫荧光法检测FOXO1在细胞中的定位情况。

结果

与对照组比较,LPS组小鼠肺组织病理评分明显升高(P<0.05),肺组织中pFOXO1(Ser256)和αENaC蛋白表达水平降低(P<0.05),二者呈正相关关系 (r=0.703, P<0.05);与对照组比较,过表达FOXO1组A549细胞中αENaC mRNA表达水平降低(P<0.05),沉默FOXO1组αENaC mRNA表达水平升高(P<0.05);与对照组比较,胰岛素组A549细胞中pFOXO1(Ser256)蛋白和αENaC mRNA表达水平升高(P<0.05),pFOXO1主要分布于细胞质中,而胰岛素+PI3K抑制剂和胰岛素+AKT抑制剂组A549细胞中αENaC mRNA和pFOXO1蛋白表达水平低于胰岛素组P<0.05)。

结论

FOXO1磷酸化失活后由细胞核穿梭至细胞浆,对αENaC的抑制作用减弱,从而上调αENaC表达。

关键词: 叉头框蛋白O1, 上皮细胞钠离子通道, 胰岛素, 急性肺损伤, 急性呼吸窘迫综合征

Abstract: Objective

To investigate the regulatory effect of forkhead box O1(FOXO1) on the alveolar epithelial sodium channel (ENac) in the lipopolysaccharide (LPS)-induced acute lung injury mice, and to illustrate the mechanism.

Methods

Twenty C57BL/6J mice were randomly divided into control group and LPS group, and there were 10 mice in each group. After treatment, the mouse samples were obtained. HE staining was used to observe the pathomorphology of lung tissue of the mice in two groups, RT-PCR method and Western blotting method were used to detect the expression levels of α-subunit ENaC(αENaC) mRNA and pFOXO1 (Ser256) protein in lung tissue of the mice in two groups.The alveolar epithelial A549 cells were cultured, and then infected with ADV-FOXO1 or shRNA-FOXO1, respectively.RT-PCR method was used to determine the expression of αENaC mRNA. The A549 cells were divided into control group, insulin group, insulin+PI3K inhibitor group, and insulin+AKT inhibitor group. After corresponding intervention, Western blotting method was used to detect the expression levels of pFOXO1 (Ser256) protein,RT-PCR method was used to determine the expression levels of αENaC mRNA, and immunofluorescence method was used to detect the intracellular localization of FOXO1.

Results

Compared with control group, the lung injury score of mice in LPS group was increased significantly (P<0.05), the expression levels of pFOXO1 (Ser256) and αENaC proteins in the lung tissue were significantly decreased(P<0.05) and they showed positively correlated relationship(r=0.703, P<0.05).Compared with control group; the expression level of αENaC mRNA in A549 cells in over-expression FOXO1 group was significantly decreased (P<0.05),and the expression level of αENaC mRNA in silencing FOXO1 group was significantly increased(P<0.05); compared with control group, the expression levels of pFOXO1 protein and αENaC mRNA in the A549 cells in insulin group were increased significantly (P<0.05), and FOXO1 was mainly located in the cytoplasm. The expression levels of αENaC mRNA and pFOXO1 protein in A549 cells in insulin+PI3K inhibitor group and insulin+AKT inhibitor group were lower than those in insulin group (P<0.05).

Conclusion

After inactiviation of FOXO1 phosphorylation,FOXO1 can translocate from nucleus to cytoplasm to weaken the inhibitory effect of αENaC and upregulate the expression of αENaC.

Key words: forkhead box O1, epithelial sodium channel, insulin, acute lung injury, acute respiratory distress syndrome

中图分类号: 

  • R563