反义基质金属蛋白酶抑制剂-1基因转染对氧化应激反应介导的肺纤维化大鼠的影响

目的:探讨反义基质金属蛋白酶抑制剂-1(TIMP-1cDNA)基因转染对氧化应激反应介导的肺纤维化大鼠的影响。方法:取40只大鼠,其中30只建立肺纤维化模型,随机分为模型组、反义组和空载组,其余10只为对照组。术后第1天,反义组和空载组向气管分别注入反义TIMP-1cDNA逆转录病毒载体和空载体,模型组和对照组注入生理盐水溶液。观察4组大鼠一般体征和肺组织病理学变化,对比肺系数、丙二醛(MDA)、超氧化物歧化酶(SOD)水平及谷胱甘肽/氧化型谷胱甘肽(GSH/GSSG)比值;对比肺组织中基质金属蛋白酶-9(MMP-9)、TIMP-1、Ⅳ型胶原mRNA和蛋白相对表达量及MMP-9/TIMP-1比值。结果:对照组大鼠一般状态良好,但模型组和空载组状态逐渐变差,反义组有所改善;对照组肺组织正常,模型组和空载组肺纤维化及组织结构损伤严重,反义组较模型组减轻,但仍有炎症细胞。肺系数、肺组织MDA水平、TIMP-1、Ⅳ型胶原mRNA和蛋白相对表达量对照组最低,反义组其次,模型组和空载组最高;肺组织SOD水平、GSH/GSSG对照组最高,反义组其次,模型组和空载组最低;肺组织MMP-9/TIMP-1 mRNA相对表达量及MMP-9/TIMP-1比值组间比较,反义组最高,模型组和空载组其次,对照组最低。上述指标模型组和空载组均相近(P0.05),其余每2组间比较差异均显著(均P0.05)。结论:反义TIMP-1基因转染可减轻氧化应激反应介导的肺纤维化,可能与下调TIMP-1、上调MMP-9 mRNA和蛋白表达有关。

Effect of antisense TIMP-1 gene transfection on oxidative stress-mediated pulmonary fibrosis in rats

Objective: To investigate the effect of antisense tissue inhibitor of metalloproteinase-1 (TIMP-1cDNA) transfection on oxidative stress-mediated pulmonary fibrosis in rats. Methods: Thirty of 40 rats were modeled as pulmonary fibrosis. They were randomly divided into model group, antisense group and no-load group (n=10 each), and the remaining 10 served as control group. On the first postoperative day, the antisense group and no-load group were injected into the trachea with antisense TIMP-1 cDNA retroviral vector and empty vector respectively. The model group and the control group were injected with physiological saline solution for 28 days. The general signs of the rats were observed. The pathological changes of lung tissues in each group were observed. The pulmonary coefficient, the levels of lung malondialdehyde (MDA), superoxide dismutase (SOD) levels and glutathione/glutathione oxidized (GSH/GSSG) were compared. The relative expression levels of matrix metalloproteinase-9 (MMP-9), TIMP-1, type IV collagen mRNA and protein and MMP-9/TIMP-1 in lung tissue were compared. Results: The rats in the control group were generally in good condition, those in the model group and the empty group gradually deteriorated, and those in the antisense group improved. Pathological observation showed that the lung tissue of the control group was normal. Pulmonary fibrosis and structural damage were severe in the model group and the empty group, and those in the antisense group were relieved as compared with the model group, but there were still inflammatory cells. The lung coefficient, MDA levels in lung tissues, TIMP-1, and IV collagen mRNA and protein relative expression were the lowest in control group, the second in antisense group, the highest in model group and no-load group. The levels of SOD, GSH/GSSG in lung tissues were the highest in the control group, the second in antisense group, the lowest in model group and no-load group. The relative expression levels of MMP-9 mRNA and MMP-9/TIMP-1 in lung tissues in the antisense group were the highest, followed by the model group and no-load group, lowest in the control group. The above indexes were similar between the model group and the no-load group (P>0.05), and there were significant differences between the rest each two groups (all P<0.05). Conclusion: Antisense TIMP-1 gene transfection can alleviate oxidative stress-mediated pulmonary fibrosis, which may be related to down-regulation of TIMP-1, and up-regulation of MMP-9 mRNA and protein expression.