高氧肺损伤形成过程中小窝蛋白-1、TGF-β1表达关系的体内外研究

Study on relationship of caveolin-1 and TGF-β1 in hyperoxia-induced lung injury in vivo and in vitro

目的通过建立高氧肺损伤动物模型和体外细胞培养的方法,从体内和体外两方面来研究小窝蛋白-1(caveolin-1)和TGF-β1的表达关系,以探讨其发病机制。方法 (1)体内实验:建立早产鼠高氧肺损伤模型。于给氧后1、3、7d留取肺组织标本,在光学显微镜下观察肺组织形态学变化,免疫组织化学法检测相应时间点小窝蛋白-1、TGF-β1的表达水平。(2)体外实验:建立高氧A549细胞损伤模型。于给氧后12、24、48h收集细胞,免疫荧光双染检测相应时间点小窝蛋白-1、TGF-β1表达水平的相关性。结果 (1)体内结果:小窝蛋白-1在对照组肺组织中均有较高水平表达。与对照组比较,高氧组肺组织caveolin-1的表达水平出现降低,在3、7d明显降低(P<0.05);TGF-β1在对照组肺组织中均有较低水平表达。与对照组比较,高氧组肺组织TGF-β1的表达水平升高,在3、7d明显升高(P<0.05)。(2)体外结果:对照组,小窝蛋白-1的高表达伴随着TGF-β1的低表达;高氧组,随着通氧时间的延长,小窝蛋白-1表达逐渐减弱,TGF-β1表达逐渐增强。结论在高氧肺损伤的发生、发展过程中,Caveolin-1表达显著性减少,TGF-β1表达持续性增多,二者呈拮抗关系,提示Caveolin-1可能通过下调TGF-β1的产生而具有抗纤维化能力。

Objective Through the establishment of model for hyperoxia-induced lung injury in vivo and vitro,the dynamic changes of caveolin-1（Cav-1） and transforming growth factor batal（TGF-β1）,and the mechanism of hyperoxic lung injury were investigated.Methods In vivo：a mode1 of hyperoxia in preterm rats was established.The lung tissue in two groups was obtained at 1,3 and 7 days after exposing to either room air or hyperoxia.The change of morphology were observed under inverted microscope,and the expression of Caveol in-1,TGF-β1 in the lung tissue was detected in immunohistochemistry.In vitro：Hyperoxia injury A549 cell model was established.After exposure to oxygen or room air for 12,24 and 48 h,the relationship of expression between Caveolin-1 and TGF-β1 was detected by double immunofluorescence staining technique,followed by laser scan with focus microscope.Results In vivo：the expression of Caveolin-1 remained at a higher level in the air group.Compared with control group,the expression of caveolin-1 in the hyperoxia exposure group began to decrease from 1 day,markedly at 3,7 days（P＆lt;0.05）.The expression of TGF-β1 remained at a lower level in the air group.Compared with control group,the expression of TGF-β1 in the hyperoxia exposure group began to increase significantly from 1 day,markedly at 3,7 days（P＆lt;0.05）.In vitro：In the control group,the high expression of Caveolin-1 was associated with low expression of TGF-β1;Compared with control group,with prolonged hyperoxia exposure,the content of Caveolin-1 reduced continuously,but TGF-β1 increased gradually.Conclusion The expression level of Caveolin-1 reduced significantly and the TGF-β1 increased progressively,when exposed to hyperoxia,which means that Caveolin-1 maybe has the anti-pulmonary fibrosis function through decreasing TGF-β1 generation.