AMPK调控内质网应激抵抗COPD大鼠肺泡上皮细胞凋亡的实验研究

目的:初步探讨AMPK在内质网应激所致COPD大鼠肺泡上皮细胞凋亡中所起的作用及机制。方法:实验分三组:对照组,COPD模型组,AICAR干预组,以香烟烟雾烟熏加气管内滴注脂多糖方法构建COPD大鼠模型,取大鼠肺组织行HE染色病理观察,免疫组化,western blot检测p-AMPK/AMPK,ORP150,caspase-3及CHOP表达,TUNEL法检测各组凋亡情况。结果:病理HE染色提示模型组大量炎症细胞浸润,肺大疱形成,支气管壁发生狭窄;AICAR干预组炎症细胞较模型组减少。与正常对照组相比,免疫组化及western blot均提示模型组中p-AMPK和ORP150蛋白表达含量增强,差异有统计学意义(P0.05)。而AICAR干预组中p-AMPK/AMPK及ORP150蛋白表达较模型组明显上升,差异有统计学意义(P0.05)。内质网应激相关凋亡指标CHOP及caspase-3的表达在模型组明显增强,较正常组比较差异有显著性(P0.05),而AICAR组中凋亡指标较模型组明显下调。结论:AMPK可以保护肺泡上皮细胞免于香烟烟雾所致内质网应激凋亡,且有可能通过增加ORP150来实现其保护作用。

The Mechanism of AMPK Regulate Endoplasmic Reticulum Stress to Resist the Epithelial Cell Apoptosis in COPD Rats

ABSTRACT Objective: To explore the effect and mechanism of AMPK on apoptosis of alveolar epithelial cells induced by endo- plasmic reticulum stress in COPD rats. Methods: the rats were divided into three groups: control group, model group, AICAR interven- tion group, establishment of rat model of chronic obstructive pulmonary disease by smoking smoke inhalation and intratracheal instilla- tion of lipopolysaccharide. The HE staining of rat lung tissue pathological observation, immunohistochemical detection of p-AMPK/AMPK, western blot the expression of Caspase-3, ORP150, and CHOP. Apoptosis were detected by TUNEL method. Results: the HE staining showed that the model group of pulmonary bullae formation, inflammatory cell infiltration, inflammatory cells in AICAR group was lower than that of model group. Compared with the normal control group, immunohistochemistry and Western blot showed that p-AMPK/ AMPK and ORP150 protein expression decreased in the model group, the difference was statistically significant (P<0.05), and AICAR in the intervention group p-AMPK/ AMPK and ORP150 protein expression were significantly increased compared with the model group, the difference was statistically significant (P<0.05). Endoplasmic reticulum stress related apoptosis The expression of CHOP and caspase-3 apoptosis index increased significantly in the model group, there was significant difference compared with normal group (P<0.05), while in group AICAR, apoptosis index down significantly compared with the model group. Conclusion: AMPK can protect alveolar epithelial cells from cigarette smoke induced endoplasmic reticulum stress and apoptosis, it was possible to achieve its protective effect the increase of ORP150.