Li Yuping, Luo Bailing, Zhang Li, Ma Miao, Guo Xianling
Department of Respiratory Medicine, Xiangya Hospital of Central South University, Changsha 410008, China.
Department of Respiratory Medicine, Xiangya Hospital of Central South University, Changsha 410008, China. Email:
Zhonghua Jie He He Hu Xi Za Zhi. 2014 Jan;37(1):30-5.
To investigate alveolar epithelial cell apoptosis induced by endoplasmic reticulum stress in a rat model of chronic obstructive pulmonary disease (COPD) and the potential protective effect of resveratrol.
The COPD rat model was established by intratracheal instillation of lipopolysaccharide (LPS) and exposure to cigarette smoke daily. Forty-eight male Sprague-Dawley rats were randomly divided into 4 groups (n = 12 each): a normal control group, a resveratrol control group (resveratrol 25 mg × kg⁻¹ × d⁻¹ gavage), a COPD group (COPD rat model established), and a resveratrol intervention group (COPD model rats receiving resveratrol 25 mg × kg⁻¹ × d⁻¹ gavage). Spirometry was conducted and the lung pathological changes were observed. The protein expression of CCAAT/enhancer binding protein homologous protein (CHOP) and caspase-12 were detected by immunohistochemistry and Western blot, and alveolar epithelial apoptosis was analyzed by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL). Statistical analysis among groups were carried out by one way analysis of variance followed by LSD-t test between 2 groups.
Significant decrease of FEV0.3/FVC [(59 ± 4)%] and dynamic lung compliance [(0.154 ± 0.013) ml/cm H₂O, 1 cm H₂O = 0.098 kPa] and increase of airway resistance [(0.651 ± 0.046) cm H₂O × ml⁻¹× s⁻¹] were found in the COPD group when compared with the normal control group [(82 ± 4)%, (0.401 ± 0.033) ml/cm H₂O, (0.404 ± 0.033) cm H₂O × ml⁻¹ × s⁻¹] (t = -14.48, 16.48, P < 0.05). The FEV0.3/FVC [(71 ± 5)%] and dynamic lung compliance [(0.302 ± 0.023) ml/cm H₂O] of the resveratrol intervention group were significantly improved when compared with those of the COPD group, and the airway resistance [(0.442 ± 0.036) cm H₂O × ml⁻¹ × s⁻¹] also decreased (t = -10.02-10.37, P < 0.05). Significant small airway inflammation and emphysema were seen in the lung tissue of COPD group, while significant improvement was observed in the resveratrol intervention group when compared with COPD group. The lung tissue immunohistochemistry integrated optical density (IOD) of CHOP and caspase-12 (9 778 ± 217, 12 009 ± 346) of the COPD group increased significantly when compared with the normal control group (960 ± 94, 1 124 ± 112) (t = -100.43, - 90.43, P < 0.05), while the IODs of the resveratrol intervention group (5 799 ± 177, 6 720 ± 173) decreased significantly when compared with the COPD group (t = 45.32, 43.93, P < 0.05). Western blot results showed that the relative quantification of CHOP (0.910 ± 0.053) and caspase-12 (1.104 ± 0.026) increased in the COPD group when compared with the normal control group (0.204 ± 0.021, 0.133 ± 0.013, t = -36.04, -115.03, P < 0.05), while the ratios of the resveratrol intervention group (0.462 ± 0.037, 0.642 ± 0.011) decreased significantly when compared with COPD group (t = 24.22, 60.59, P < 0.05). Higher apoptosis index was seen in the COPD group [(39.8 ± 1.6)%] when compared with the resveratrol intervention group [(26.3 ± 1.5)%] and the normal control group [(6.4 ± 0.6)%] (t = 20.21, -49.94, P < 0.05).
Endoplasmic reticulum stress, which induced apoptosis of alveolar epithelial cells, was observed in this COPD model. Resveratrol was shown to alleviate endoplasmic reticulum stress and attenuate alveolar epithelial apoptosis.
在慢性阻塞性肺疾病（COPD）大鼠模型中研究内质网应激诱导的肺泡上皮细胞凋亡以及白藜芦醇的潜在保护作用。
通过气管内滴注脂多糖（LPS）并每日暴露于香烟烟雾建立COPD大鼠模型。48只雄性Sprague-Dawley大鼠随机分为4组（每组n = 12）：正常对照组、白藜芦醇对照组（白藜芦醇25 mg×kg⁻¹×d⁻¹灌胃）、COPD组（建立COPD大鼠模型）和白藜芦醇干预组（COPD模型大鼠接受白藜芦醇25 mg×kg⁻¹×d⁻¹灌胃）。进行肺功能测定并观察肺组织病理变化。通过免疫组织化学和蛋白质印迹法检测CCAAT/增强子结合蛋白同源蛋白（CHOP）和半胱天冬酶-12的蛋白表达，并通过末端脱氧核苷酸转移酶介导的缺口末端标记法（TUNEL）分析肺泡上皮细胞凋亡。组间统计分析采用单因素方差分析，随后进行两组间的LSD-t检验。
与正常对照组[（82±4）%，（0.401±0.033）ml/cm H₂O，（0.404±0.033）cm H₂O×ml⁻¹×s⁻¹]相比，COPD组的第0.3秒用力呼气容积/用力肺活量[（59±4）%]和动态肺顺应性[（0.154±0.013）ml/cm H₂O，1 cm H₂O = 0.098 kPa]显著降低，气道阻力[（0.651±0.046）cm H₂O×ml⁻¹×s⁻¹]增加（t = -14.48，16.48，P < 0.05）。与COPD组相比，白藜芦醇干预组的第0.3秒用力呼气容积/用力肺活量[（71±5）%]和动态肺顺应性[（0.302±0.023）ml/cm H₂O]显著改善，气道阻力[（0.442±0.036）cm H₂O×ml⁻¹×s⁻¹]也降低（t = -10.02 - 10.37，P < 0.05）。COPD组肺组织可见明显的小气道炎症和肺气肿，而与COPD组相比，白藜芦醇干预组有显著改善。与正常对照组（960±94，1 124±112）相比，COPD组肺组织CHOP和半胱天冬酶-12的免疫组织化学积分光密度（IOD）（9 778±217，12 009±346）显著增加（t = -100.43，- 90.43，P < 0.05），而与COPD组相比，白藜芦醇干预组的IOD（5 799±177，6 720±173）显著降低（t = 45.32，43.93，P < 0.05）。蛋白质印迹结果显示，与正常对照组（0.204±0.021，0.133±0.013，t = -36.04，-115.03，P < 0.05）相比，COPD组CHOP（0.910±0.053）和半胱天冬酶-12（1.104±0.026）的相对定量增加，而与COPD组相比，白藜芦醇干预组的比值（0.462±0.037，0.642±0.011）显著降低（t = 24.22，60.59，P < 0.05）。与白藜芦醇干预组[（26.3±1.5）%]和正常对照组[（6.4±0.6）%]相比，COPD组的凋亡指数更高[（39.8±1.6）%]（t = 20.21，-49.94，P < 0.05）。
在该COPD模型中观察到内质网应激诱导肺泡上皮细胞凋亡。白藜芦醇可减轻内质网应激并减弱肺泡上皮细胞凋亡。
