Sestrin2在吸烟诱导的肺泡Ⅱ型上皮细胞损伤中的作用机制  

Protective effect and mechanism of Sestrin2 in the development of pulmonary alveolar type Ⅱ epithelial cell injury induced by cigarette smoking

作　　者：姜晓亮[1] 刘雪 刘云鹏[1] 付慧 刘星[1] 杨志伟[1] JIANG Xiaoliang;LIU Xue;LIU Yunpeng;FU Hui;LIU Xing;YANG Zhiwei(Institute of Laboratory Animal Sciences,Chinese Academy of Medical Sciences（CAMS;Comparative Medicine Center,Peking Union Medical College（PUMC）,Beijing 100021,China)

机构地区：[1]中国医学科学院医学实验动物研究所,北京协和医学院比较医学中心,北京100021

出　　处：《中国比较医学杂志》2018年第5期46-52,共7页Chinese Journal of Comparative Medicine

基　　金：国家自然科学基金面上项目(编号：81600387);国家自然科学基金青年项目(编号：81600334); 中国医学科学院医学与健康科技创新工程重大协同创新项目(编号：2016-I2M-1-016); 生命科学学会联合体“青年人才托举工程”

摘　　要：目的探索Sestrin2在吸烟诱导的肺泡Ⅱ型上皮细胞损伤中的作用机制。方法使用香烟烟雾提取物(CSE)处理人肺泡Ⅱ型上皮细胞复制吸烟诱导的肺泡上皮细胞损伤。使用DCFDA荧光探针检测ROS的生成,ELISA方法检测炎症因子TNF-α和IL-8的水平,免疫印迹方法检测Sestrin2的表达以及过氧化物酶(Prx-SO_(2/3)H)的氧化情况。同时检测Sestrin2 siRNA以及阿奇霉素处理后细胞中Sestrin2和Prx-SO_(2/3)H的表达以及ROS的生成和炎症因子的分泌。结果 CSE处理A549细胞后Sestrin2的表达降低,Prx-SO_(2/3)H的表达增加,ROS的产量升高,TNF-α和IL-8的分泌增多,阿奇霉素能够显著缓解CSE诱导的氧化应激及炎症损伤(P<0.05)。A549细胞经Sestrin2 siRNA沉默后,超氧化的Prx-SO_(2/3)H表达增多,ROS的产量升高,TNF-α和IL-8的分泌增多,但额外给予阿奇霉素不能缓解细胞的氧化应激及炎症损伤。结论 Sestrin2通过抑制细胞内ROS的生成在吸烟诱导的肺泡Ⅱ型上皮细胞损伤中发挥重要的保护作用,其机制与Sestrin2催化还原超氧化的过氧化物酶有关。Objective To explore the role of Sestrin2 in pulmonary alveolar type II epithelial cell injury induced by cigarette smoking and its mechanism of action. Methods The cell injury model was induced by cigarette smoke extract（CSE） in the human pulmonary alveolar type II epithelial A549 cells. The generation of ROS was detected by DCFDA fluorescence probe. The levels of inflammatory factors TNF-α and IL-8 were determined by ELISA,and the expression of Sestrin2 and the peroxiredoxin,Prx-SO2/3H,was detected by Western blot. In addition,all the events were also measured in the A549 cells which were transfected with Sestrin2 siRNA and treated with azithromycin. Results After the CSE treatment,the expression of Sestrin2 in the A549 cells was decreased,the expression of Prx-SO2/3H was increased,the ROS production,secretion of cytokines TNF-α and IL-8 were increased（P 0. 05）. These changes were partly reducedby azithromycin,indicating that azithromycin significantly relieved CSE-induced oxidative stress and inflammatory injury.Silencing of Sestrin2 in the A549 cells result ed in an increase of Prx-SO2/3H expression,ROS production and the secretion of the cytokines TNF-α and IL-8. However,oxidative stress and inflammatory injury were not alleviated with the addition of azithromycin in the Sestrin2 siRNA silencing A549 cells. Conclusions Sestrin2 plays an protective role in the pulmonary alveolar type II epithelial cell injury induced by cigarette smoking through negatively regulating the level of intracellular ROS via catalyzing the reduction of the hyperoxidized peroxiredoxin Prx-SO2/3H.

关 键 词：肺泡上皮细胞损伤 慢性阻塞性肺疾病 香烟烟雾 Sestrin2 活性氧 

分 类 号：R-33[医药卫生]