Yang Min, Chen Ping, Peng Hong, Shen Qin, Chen Yan
Department of Respiratory Medicine, the Second Xiangya Hospital of Central South University, Changsha 410011, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2010 Sep;33(9):665-9.
To observe the expression and activity of cytochrome C oxidase and pulmonary endothelial apoptosis in lungs of COPD patients, and therefore to investigate the pathogenesis of COPD.
According to COPD diagnostic criteria and patients' smoking status, 20 patients who had undergone lung resections were divided into 3 groups: group A, non-smokers without COPD (7 patients); group B, smokers without COPD (7 patients); and group C, smokers with COPD (6 patients). Their normal lung tissues were used in the study. TUNEL assay was used to assess pulmonary vascular endothelial apoptosis. Cytochrome C oxidase (COX) activity was measured by spectrophotometry. Semi-quantitative polymerase chain reaction and Western blot were used to measure COX subunit II (COXII) mRNA and protein expression respectively. Moreover, immunohistochemistry was used to detect COXII protein expression in pulmonary endothelial cells. One-way ANOVA and LSD-t test were used for statistics.
The apoptotic index of pulmonary vascular endothelial cells in group C [(13.8 ± 1.9)%] was significantly higher than that in group B [(9.6 ± 0.8)%] and group A [(5.9 ± 1.0)%]. While COX activity and COXII mRNA expression of lung tissues and COXII protein expression of pulmonary endothelial cells in group C [(4.4 ± 0.7) × 10⁵ U/kg, (0.76 ± 0.17) and (14.5 ± 1.6), respectively] were significantly lower than those in group A [(7.6 ± 0.4) × 10⁵ U/kg, 0.86 ± 0.20 and 23.8 ± 3.4, respectively] and group B [(6.0 ± 0.6) × 10⁵ U/kg, 0.81 ± 0.15 and 18.6 ± 2.1, respectively] (t = -13.66 - 13.27, all P < 0.05). The correlation analyses showed that COX activity was correlated positively with FEV₁ % pred and FEV₁/FVC (r = 0.84, 0.91, all P < 0.01), but negatively with smoking index (r = -0.78, P < 0.01). The apoptotic index of pulmonary vascular endothelial cells was negatively correlated with COXII expression (r = -0.75, P < 0.01).
Increased pulmonary vascular endothelial apoptosis and decreased COX expression and activity, which were often associated with cigarette smoking, were present in COPD patients. COX might mediate the pulmonary vascular endothelial apoptosis in COPD.
观察慢性阻塞性肺疾病（COPD）患者肺组织中细胞色素C氧化酶的表达及活性以及肺血管内皮细胞凋亡情况，以探讨COPD的发病机制。
根据COPD诊断标准及患者吸烟状况，将20例接受肺切除术的患者分为3组：A组，非吸烟且无COPD患者（7例）；B组，吸烟但无COPD患者（7例）；C组，吸烟且患有COPD患者（6例）。采用其正常肺组织进行研究。采用TUNEL法评估肺血管内皮细胞凋亡情况。用分光光度法测定细胞色素C氧化酶（COX）活性。分别采用半定量聚合酶链反应和蛋白质免疫印迹法检测COX亚基II（COXII）mRNA和蛋白表达。此外，采用免疫组织化学法检测肺血管内皮细胞中COXII蛋白表达。采用单因素方差分析和LSD-t检验进行统计学分析。
C组肺血管内皮细胞凋亡指数[（13.8±1.9）%]显著高于B组[（9.6±0.8）%]和A组[（5.9±1.0）%]。而C组肺组织COX活性、COXII mRNA表达及肺血管内皮细胞COXII蛋白表达[分别为（4.4±0.7）×10⁵U/kg、（0.76±0.17）及（14.5±1.6）]显著低于A组[分别为（7.6±0.4）×10⁵U/kg、0.86±0.20及23.8±3.4]和B组[分别为（6.0±0.6）×10⁵U/kg、0.81±0.15及18.6±2.1]（t=-13.66～-13.27，均P<0.05）。相关性分析显示，COX活性与FEV₁%pred及FEV₁/FVC呈正相关（r=0.84、0.91，均P<0.01），但与吸烟指数呈负相关（r=-0.78，P<0.01）。肺血管内皮细胞凋亡指数与COXII表达呈负相关（r=-0.75，P<0.01）。
COPD患者存在肺血管内皮细胞凋亡增加以及COX表达和活性降低的情况，且常与吸烟相关。COX可能介导了COPD患者肺血管内皮细胞凋亡。
