Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Jiangsu Normal University, Xuzhou 221116, P.R. China.
Department of Respiration, Huaihe Hospital of Henan University, Kaifeng 475000, P.R. China.
Biosci Rep. 2017 Nov 15;37(6). doi: 10.1042/BSR20170803. Print 2017 Dec 22.
During the present study, we explored the protective effects of autophagy on endoplasmic reticulum (ER) stress (ERS) induced apoptosis belonging to alveolar epithelial cells (AECs) in rat models with chronic obstructive pulmonary disease (COPD). Fifty-six 12-week-old male Sprague-Dawley (SD) rats were randomly assigned into the COPD group (rats exposed to cigarette smoke (CS)), the 3-methyladenine (3-MA) intervention group (COPD rats were administrated with 10 mg/kg autophagy inhibitors), the chloroquine (CQ)-intervention group (COPD rats were administrated 40 mg/kg CQ), and the control group (rats breathed in normal saline). The forced expiratory volume in 0.3 s/forced vital capacity (FEV/FVC%), inspiratory resistance (RI), and dynamic lung compliance (Cdyn) were measured and recorded. The expressions of PKR-like ER kinase (PERK) and CCAAT/enhancer-binding protein-homologous protein (CHOP) were detected by immunohistochemistry. The cell apoptotic rates of AECs were analyzed by terminal deoxynucleotidyl transferase (TdT) mediated dUTP-biotin nick end-labeling (TUNEL) staining. The expression levels of light chain 3 (LC3-II), p62, Beclin-1, ATG5, ATG7, Caspase-12, and Caspase-3 were detected by Western blotting. Results showed that the COPD group exhibited a lower FEV/FVC% and Cdyn, and a higher RI than the control group. Compared with the control group, the integrated optical density (IOD) values of PERK and CHOP, the apoptotic rate of AECs, and expressions of LC3-II, Beclin-1, ATG5, ATG7, Caspase-3, and Caspase-12 expressions were significantly higher, whereas p62 expression was significantly lower in the COPD group. Based on the results obtained during the present study, it became clear that the inhibition of autophagy could attenuate the ERS-induced apoptosis of AECs in rats with COPD.
在本研究中，我们探讨了自噬对慢性阻塞性肺疾病（COPD）大鼠模型肺泡上皮细胞（AEC）内质网（ER）应激（ERS）诱导凋亡的保护作用。将 56 只 12 周龄雄性 Sprague-Dawley（SD）大鼠随机分为 COPD 组（大鼠暴露于香烟烟雾（CS））、3-甲基腺嘌呤（3-MA）干预组（COPD 大鼠给予 10mg/kg 自噬抑制剂）、氯喹（CQ）干预组（COPD 大鼠给予 40mg/kg CQ）和对照组（大鼠吸入生理盐水）。测量并记录 0.3 秒用力呼气量/用力肺活量（FEV/FVC%）、吸气阻力（RI）和动态肺顺应性（Cdyn）。免疫组织化学法检测蛋白激酶 R 样内质网激酶（PERK）和 CCAAT/增强子结合蛋白同源蛋白（CHOP）的表达。末端脱氧核苷酸转移酶（TdT）介导的 dUTP-生物素缺口末端标记（TUNEL）染色分析 AEC 细胞凋亡率。Western blot 检测自噬相关蛋白 LC3-II、p62、Beclin-1、ATG5、ATG7、Caspase-12 和 Caspase-3 的表达水平。结果显示，COPD 组 FEV/FVC%和 Cdyn 低于对照组，RI 高于对照组。与对照组相比，COPD 组 PERK 和 CHOP 的积分光密度（IOD）值、AEC 凋亡率、LC3-II、Beclin-1、ATG5、ATG7、Caspase-3 和 Caspase-12 的表达明显升高，而 p62 的表达明显降低。COPD 组。基于本研究的结果，我们清楚地了解到抑制自噬可以减轻 COPD 大鼠 ER 诱导的 AEC 凋亡。
