摘要目的 探讨核因子相关因子-2(Nrf2)在COPD发病中的作用及与核因子-κB和Ⅰ-κB激酶(IKKs)之间的关系.方法 将大鼠按照完全随机方法分为对照组、模型组和干预组,每组12只,检测大鼠的肺功能和抗氧化能力.免疫组织化学SABC法和逆转录PCR法检测Nrf2、核因子-κB p65和IKKα/β的蛋白水平及mRNA表达.统计学方法采用单因素方差分析,组间两两比较采用LSD-t检验.结果 模型组大鼠FEV_(0.3)/FVC为(58.8±2.6)%,动态肺顺应性为(0.14±0.02)ml/cm H_2O(1 cm H_2O=0.098 kPa),总抗氧化能力为(0.20±0.03)U/ml,SOD抗氧化能力为(19.6±2.4)U/ml,均明显低于对照组[(86.3±2.5)%、(0.38±0.02)ml/cm H_2O、(3.16±0.31)U/ml及(56.1±2.2)U/ml];模型组大鼠的气道阻力为(0.69±0.17)cm H_2O·ml_(-1)·s~(-1),明显高于对照组的(0.34±0.06)cm H_2O·ml~(-1)·s~(-1);干预组介于两组之间.模型组大鼠Nrf2、IKKα/β和核因子-κB p65的阳性系数依次为3.23±0.31、3.80±0.16和3.85±0.18,明显高于对照组的0.91±0.45、1.17±0.42和1.30±0.34,干预组IKKα/β和核因子-κB p65的阳性系数(2.10±0.46和2.53±0.36)介于两者之间,而Nrf2的阳件系数(3.78±0.22)明显高于模型组.模型组大鼠Nff2、IKKβ和核因子-KB p65的mRNA表达分别为0.61±0.08、0.89士0.05和0.91±0.02,明显高于对照组的0.29±0.07、0.30±0.07和0.30±0.07,干预组IKKB和核因子-κB p65的mRNA表达(0.67±0.04和0.69±0.04)介于两者之间,而Nrf2的mRNA表达(0.90±0.05)明显高于模型组.结论 15d-PGJ2在COPD模型中有抗氧化应激和抗炎症作用,这可能与Nrf2增加有关.Nrf2可能通过抑制IKKβ表达从而抑制核因子.κB p65的表达水平.

abstractsObjective To study the expression of nuclear factor-erythroid 2-related factor 2 ( Nrf2) in the bronchial and lung tissues of chronic obstructive pulmonary disease ( COPD) rat models and its association with I-kappa B kinases (IKKs). Methods Rat COPD models were established by intratracheal instillation of lipopolysaccharide (LPS) twice and exposure to cigarette smoke daily. The drug intervention group received 15-deoxy-△2,14-prostaglandin J2 (15d-PGJ2) 0.3 mg/kg twice via tail venous injection. Spirometry was conducted and the pathological changes were observed. Antioxidation activities were measured and the expressions of Nrf2, IKKα/β and NF-κB p65 were detected by immunohistochemistry and RT-PCR. The differences among groups were calculated by one-way ANOVA, and comparison between groups was made by LSD- test. Results FEV_(0.3)/FVC, Cdyn values and antioxidation capacity including total anti-oxidation competence and superoxidase dismutase in the COPD group [ (58. 8 ±2. 6)% , (0. 14 ± 0. 02)ml/cm H_2O( 1 cm H_2O =0. 098 kPa), (0. 20 ±0. 03) U/ml and (19. 6 ±2. 4) U/ml, respectively] were significantly lower than those in the normal control group [ ( 86. 3 ±2. 5 ) % , ( 0. 38 ±0. 02 ) ml/ cm H_2O, ( 3. 16 ± 0. 31 ) U/ml and ( 56. 1 ± 2. 2 ) U/ml, respectively ] . RI values ( 0. 69 ± 0. 17 ) cm H_2O . ml~(-1). s~(-1) were significantly higher than that of the normal control group (0. 34 ±0. 06)cm H_2O. ml~(-1). s~(-1). The above measurements of the drug intervention group [ (74. 5 ±3. 9)% , (0. 30 ±0. 04) respectively] were between the COPD and the control groups, with airflow limitation and pulmonary ventilation improved significantly. Immunohistochemistry showed that, the positive coefficient of Nrf2, IKKα/β and NF-κB p65 were increased significantly in the COPD models (3. 23 ±0. 31, 3. 80 ±0. 16 and 3. 85 ±0. 18, respectively) , as compared with the control group (0.91 ±0.45, 1. 17 ±0.42 and 1.30 ± 0.34, respectively). The expression of IKKα/β (2. 10 ±0.46) and NF-κB p65 (2.53 ±0.36) in thelungs of the intervention group was between the COPD group and the control group, but the expression ofNrf2 (3. 78 ±0. 22) increased as compared to the COPD group. The results of RT-PCR showed that, themRNA IOD value of Nrf2, IKKβ and NF-κB p65 increased significantly in the COPD group (0. 61 ±0. 08,0. 89 ± 0. 05 and 0. 91 ± 0. 02, respectively) , as compared with the control group (0. 29 ± 0. 07, 0. 30 ± 0. 07, 0. 30 ± 0. 07, respectively), while the expression of IKKβ ( 0. 67 ± 0. 04) and NF-κB p65 (0. 69 ±0. 04) in the lungs of the drug intervention group were between the above two groups, and the expression of Nrf2 (0. 90 ±0. 05) increased as compared to the COPD group. Conclusions 15d-PGJ2 was shown to have anti-oxidation and anti-inflammation effects in this COPD model, which may be related to the increase of Nrf2. Nrf2 inhibited the expression of NF-κB p65 possibly through the down-regulation of IKKβ.