激活蛋白-1对机械通气性肺损伤小鼠肺组织炎症反应、细胞凋亡和MMP-9/TIMP-1平衡的影响

Influence of AP-1 on lung tissue inflammatory response,cell apoptosis and MMP-9/TIMP-1 balance in ventilator-induced lung injury mice

目的:研究激活蛋白-1(AP-1)对机械通气性肺损伤小鼠炎症反应、细胞凋亡和基质金属蛋白酶-9(MMP-9)/组织基质金属蛋白酶抑制因子-1(TIMP-1)平衡的影响。方法:选择2~3个月龄健康昆明小鼠30只,雌雄不限,分为假手术组、模型组和干预组3组,每组10只。假手术组行气管切开保留自主呼吸,模型组和干预组行机械通气6 h,干预组连接呼吸机后立即腹腔注射AP-1单克隆抗体(20μg)。ELISA法检测血浆白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平,取腹主动脉血检测血氧分压(PaO2),测定肺湿干重比值(W/D),HE染色观察肺组织病理学改变并进行肺损伤评分,TUNEL法检测肺组织中细胞凋亡指数,Western blot法检测肺组织中AP-1、MMP-9和TIMP-1蛋白的相对表达量。结果:与假手术组比较,模型组和干预组血浆IL-6和TNF-α水平升高,PaO2降低,肺W/D增加,肺组织病理学改变明显,肺损伤评分、细胞凋亡指数、AP-1和MMP-9蛋白相对表达量升高,TIMP-1蛋白相对表达量降低;与模型组比较,干预组血浆IL-6和TNF-α水平下降,PaO2升高,肺W/D降低,肺组织病理学改变减轻,肺损伤评分、细胞凋亡指数、AP-1和MMP-9蛋白相对表达量降低,TIMP-1蛋白相对表达量升高(P<0.05)。结论:外源性抑制AP-1表达可改善机械通气性肺损伤程度,减轻炎症反应和细胞凋亡,调节MMP-9/TIMP-1平衡。

Aim:To study the influence of of activator protein-1(AP-1)on lung tissue inflammatory response,cell apoptosis and matrix metalloproteinase-9(MMP-9)/tissue matrix metalloproteinase inhibitor-1(TIMP-1)balance in ventilator-induced lung injury mice.Methods:A total of 30 healthy Kunming mice with age of 2-3 months were chosen,male or female.They were randomly allocated into 3 groups,sham-operation group,model group and intervention group,with 10 mice in each group.In sham-operation group,tracheotomy was performed to preserve spontaneous breathing.The model group and intervention group received mechanical ventilation for 6 hours and intervention group was given intraperitoneal injection of AP-1 monoclonal antibody(20μg)after receiving ventilator.Plasma interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were detected by ELISA.Abdominal aortic blood was used to detect partial pressure of blood oxygen(PaO2).The ratio of wet to dry weight(W/D)of lung was calculated,and the pathological changes and injury score of lung tissue were observed by HE staining.The apoptosis index of lung tissue was detected by TUNEL method.AP-1,MMP-9 and TIMP-1 in lung tissue were detected by Western blot.Results:Compared with sham-operation group,plasma IL-6 and TNF-αin model group and intervention group increased significantly,PaO2 decreased,W/D of lung was higher,the pathological changes of lung tissue were obvious,lung injury score increased,apoptosis index was higher,the expressions of AP-1 and MMP-9 increased,while that of TIMP-1 decreased;compared with model group,plasma IL-6 and TNF-αin intervention group was lower,PaO2 increased,W/D of lung decreased,pathological changes of lung tissue alleviated,lung injury score decreased,apoptosis index was lower,the expressions of AP-1 and MMP-9 decreased,while that of TIMP-1 increased(P<0.05).Conclusion:Exogenous intervention of AP-1 could alleviate the ventilator-induced lung injury,inflammation disorder,apoptosis and MMP-9/TIMP-1 imbalance.