Angiotensin-(1-7) Attenuated Cigarette Smoking-related Pulmonary Fibrosis via Improving the Impaired Autophagy Caused by Nicotinamide Adenine Dinucleotide Phosphate Reduced Oxidase 4-Dependent Reactive Oxygen Species
Angiotensin-(1-7) Attenuated Cigarette Smoking-related Pulmonary Fibrosis via Improving the Impaired Autophagy Caused by Nicotinamide Adenine Dinucleotide Phosphate Reduced Oxidase 4-Dependent Reactive Oxygen Species
复制标题
血管紧张素 (1-7) 通过改善烟酰胺腺嘌呤二核苷酸磷酸还原氧化酶 4 依赖性活性氧引起的自噬受损来减轻吸烟相关的肺纤维化
DOI：
10.1165/rcmb.2017-0284oc
复制
发表时间：
2018-09-01
影响因子：
6.4
通讯作者：
Meng, Ying
中科院分区：
文献类型：
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作者：
Pan, Miaoxia;Zheng, Zemao;Meng, Ying
吸烟被认为是肺纤维化的主要危险因素。血管紧张素(Ang)II已被报道可加重吸烟所致的肺纤维化，而Ang-(1-7)对吸烟所致肺纤维化的作用尚不清楚。由活性氧(ROS)激活的自噬被认为是肺纤维化的新机制。然而，自噬是否参与了吸烟所致肺纤维化的调控仍有待研究。在此，我们旨在通过调节自噬和ROS来研究Ang-(1-7)在吸烟相关肺纤维化中的作用。在体内，持续向被动吸烟大鼠灌胃Ang-(1-7)8周。在体外，原代肺成纤维细胞在暴露于香烟烟雾提取物(CSE)之前，用抗氧化剂、烟酰胺腺嘌呤二核苷酸磷酸还原氧化酶(NOX)4siRNA或轻链(LC)3B siRNA进行预处理。用GFP-mCherry Red荧光蛋白-LC3腺病毒检测细胞内的自噬通量。我们发现，Ang-(1-7)可降低体内过氧化氢(H_2O_2)浓度、NOX4蛋白水平和自噬损伤，并改善吸烟刺激所致的肺纤维化。在体外，CSE处理增加了NOX4蛋白的表达和ROS的产生，导致受损的自噬小体在成纤维细胞中积累。LC3B缺失可促进CSE诱导的胶原合成。用抗氧化剂或NOX4 siRNA处理可抑制CSE诱导的自噬通量和胶原生成不足。相反，Ang-(1-7)的作用与CSE的作用相反。综上所述，Ang-(1-7)通过减轻体内和体外NOX4依赖的ROS引起的受损自噬，改善吸烟所致的肺纤维化。
Cigarette smoking is acknowledged as the major risk factor of pulmonary fibrosis. Angiotensin (Ang) II has been reported to aggravate smoking-induced lung fibrosis, whereas the effect of Ang-(1-7) on smoking-related lung fibrosis remains unknown. The autophagy, being activated by reactive oxygen species (ROS), is identified as a novel mechanism of pulmonary fibrosis. However, whether autophagy is involved in regulation of smoking-induced lung fibrosis still needs investigation. Here, we aim to investigate the effect of Ang-(1-7) on smoking-related lung fibrosis by the regulation of autophagy and ROS. In vivo, Ang-(1-7) was constantly infused into passive smoking rats for 8 weeks. In vitro, primary lung fibroblasts were pretreated with antioxidant, nicotinamide adenine dinucleotide phosphate reduced oxidase (NOX) 4 siRNA, or light chain (LC) 3B siRNA before exposure to cigarette smoke extract (CSE). GFP-mCherry red fluorescent protein-LC3 advenovirus was introduced to evaluate the autophagic flux in cells. We found that Ang-(1-7) reduced hydrogen peroxide (H2O2) concentration, protein levels of NOX4, and autophagy impairment, as well as improving lung fibrosis induced by smoking stimulation in vivo. In vitro, CSE treatment elevated NOX4 protein expression and ROS production, resulting in the accumulation of impaired autophagosomes in fibroblasts. LC3B depletion enhanced CSE-induced collagen synthesis. Treatment with antioxidants or NOX4 siRNA inhibited CSE-induced insufficient autophagic flux and collagen production. In contrast, the action of Ang-(1-7) opposed the effects of CSE. In conclusion, Ang-(1-7) improves smoking-induced pulmonary fibrosis via attenuating the impaired autophagy caused by NOX4-dependent ROS in vivo and in vitro.