实用医学杂志 ›› 2022, Vol. 38 ›› Issue (1): 38-44.doi: 10.3969/j.issn.1006⁃5725.2022.01.008

• 基础研究 • 上一篇    下一篇

细胞自噬调控上皮间质转化在肺纤维化中的作用机制

胡琴1,2,3 张晨曦4 柯少瑞1,2,3   

  1. 河南中医药大学1 呼吸疾病中医药防治省部共建协同创新中心,2 河南省中医药防治呼吸病重点实验室, 3 中医药科学院,4 药学院(郑州 450046)

  • 出版日期:2022-01-10 发布日期:2022-01-10
  • 通讯作者: 柯少瑞 E⁃mail:shaoruike0902@163.com
  • 基金资助:
    国家自然科学基金项目(编号:82004090);河南省中原青年拔尖人才项目(编号:ZYQR201912189);河南省博士后科研项目(编号:19030074)

Mechanism of autophagy regulating epithelial mesenchymal transformation in pulmonary fibrosis

HU Qin*,ZHANG Chenxi,KE Shaorui.   

  1. Co ⁃construction Collaborative Innovation Center for Chinese Medicine and Respiratory Diseases by He′nan & Education Ministry of P.R.,He′nan University of Chinese Medicine,Zhengzhou 450046,China;*He′nan Key Laboratory of Chinese Medicine for Respiratory Disease,He′nan University of Chinese Medicine,Zhengzhou 450046,China;*Academy of Chinese Medicine Sciences,He′nan University of Chinese Medi⁃ cine,Zhengzhou 450046,China 

  • Online:2022-01-10 Published:2022-01-10
  • Contact: KE Shaorui E⁃mail:shaoruike0902@163.com

摘要:

目的 探讨细胞自噬在特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)中的作用机制及 其变化对调控肺泡上皮间质转化(epithelial⁃mesenchymal transition,EMT)的影响,为进一步阐明IPF 的发病 机制提供实验依据。方法 采用倒置显微镜观察不同浓度转化生长因子(transforming growth factor⁃β TGF⁃β1)作用于人源肺泡上皮细胞 A549 后其形态学改变;CCK⁃8 法检测不同浓度 TGF⁃β1 A549 细胞活 力的影响;Western blot 检测不同浓度 TGF⁃β1 对自噬和 EMT 相关蛋白表达的影响,筛选出最佳的诱导浓度 及时间,建立纤维化体外模型;透射电子显微镜(TEM)观察 5 ng/mL TGF⁃β1 A549 细胞自噬的影响;造模成功后,将A549细胞分为空白组(Control)、模型组(5 ng/mL TGF⁃β1)、RAPA组(10 nmol/L RAPA)、TGF⁃β1 + RAPA(5 ng/mL TGF⁃β1+10 nmol/L RAPA)组,Western blot 和免疫荧光法检测加入自噬激动剂雷帕霉素 rapamycin,RAPA)后,自噬和 EMT 相关蛋白的表达变化。结果 与对照组相比,TGF⁃β1 处理后细胞形态 由不规则多边形转变为梭形且细胞分散开来,呈现出 EMT 的典型表象。CCK⁃8 结果显示,在实验浓度范 围内,TGF⁃β1 A549 细胞无明显的细胞毒性作用(P > 0.05)。Western blot 结果显示,与对照组相比,经 TGF⁃β1 浓度梯度诱导的各组 Beclin1、E⁃cadherin 的蛋白表达下调,p62、N⁃cadherin 的蛋白表达上调(P < 0.05)。TEM 结果显示,与对照组相比,TGF⁃β1 诱导后细胞形态向梭形转变,且自噬溶酶体数量显著减少。 加入 RAPA 之后,Western blot 和免疫荧光结果显示,与模型组相比,RAPA Beclin1、E⁃cadherin、LC3 蛋白 表达上调,p62、N⁃cadherin、Fibronectin 蛋白表达下调(P < 0.05)。结论 TGF⁃β1 可下调 A549 细胞自噬水 平,促进细胞EMT 发生,RAPA 在提高自噬水平的同时可抑制EMT 从而缓解肺纤维化

关键词:

特发性肺纤维化,  , 自噬,  , TGF?β1, 雷帕霉素,  , 细胞上皮间质转化

Abstract:

Objective To explore the mechanism of autophagy in idiopathic pulmonary fibrosis(IPF)and the impact of autophagy modifications on EMT regulation,as well as to offer an experimental foundation for further IPF pathogenesis research. Methods Different concentrations of transforming growth factor⁃β(TGF⁃β1)was used to induce human alveolar epithelial cells A549 cells,and changes of cell morphology were observed by microscope. CCK8 assay detected the effects of different concentrations of TGF ⁃ β1 on A549 cell viability. Western blot mea⁃ sured the effects of different concentrations of TGF⁃β1 on the expression of autophagy and EMT⁃related proteins and the optimal induction concentration and time were selected to establish the model of IPF in vitro.Transmission electron microscopy(TEM)was used to observe the effects of 5 ng/mL TGF⁃β1 on autophagy of A549 cells. RAPA an autophagy agonist,was used to study the effect of autophagy on EMT. A549 cells were divided into four groups:control,model(5 ng/mL TGF⁃β1),RAPA(10 nmol/L RAPA),and TGF⁃β1+RAPA(5 ng/mL TGF⁃β1 +10nmol/L RAPA). Western blot and Immunofluorescence were used to detect the expression of autophagy and EMT⁃ related proteins after the treatment of rapamycin(RAPA),an autophagy agonist. Results Compared with the control group,the cell morphology of the experimental group changed from irregular polygon to spindle shape and the cells were scattered,showing the typical appearance of EMT. TGF⁃β1 had no significant cytotoxic effect on A549 cells in the experimental concentrations range(P > 0.05). Compared with the control group,the protein expressions of Beclin1 and E ⁃cadherin in the TGF ⁃β1 concentration gradient induced groups were decreased,while the protein expressions of p62 and N⁃cadherin were increased(P < 0.05). TEM showed that compared with the control group the cell morphology changed to spindle shape after TGF⁃β1 treatment,and the number of autolysosomes decreased significantly. Western blot and Immunofluorescence data showed that in RAPA group,the expressions of LC3 Beclin1,and E⁃cadherin were up⁃regulated,while the expressions of p62,N⁃cadherin,and Fibronectin were down⁃ regulated(P < 0.05). Conclusion TGF⁃β1 can suppress the level of autophagy and promote the occurrence of EMT in A549 cells,whereas RAPA enhanced autophagy may alleviate pulmonary fibrosis by inhibiting EMT process.

Key words:

idiopathic pulmonary fibrosis, autophagy, transforming growth factor ? β1, RAPA, epithelial?mesenchymal transition