Hippo通路相关分子在先天性膈疝肺发育不良大鼠模型中的表达及意义

Expression and significance of Hippo pathway related molecules in a rat model of congenital diaphragmatic hernia with pulmonary dysplasia

目的了解Hippo信号通路主要组成分子在先天性膈疝(congenital diaphragmatic hernia,CDH)模型大鼠胎肺组织中的表达情况,初步探讨该通路与CDH肺发育不良的关系。方法应用除草醚建立CDH大鼠模型,选取模型组中单纯左侧膈疝的胎鼠左肺作为研究对象,通过免疫印迹法和RT-PCR分别检测肺组织中Lats1、Taz和Yap(pYap)表达情况并与对照组胎鼠的左肺组织进行比较。结果Lats1、Taz和Yap在模型胎鼠和正常胎鼠的支气管、肺上皮细胞及肺动脉壁中都有表达。模型组的Yap蛋白及其mRNA的表达量分别为2.3333±0.3675和1.2433±0.1033明显高于对照组的1.2509±0.3886和0.9833±0.0650,两组比较,差异有统计学意义(P<0.05);而Lats1蛋白及其mRNA和Yap蛋白磷酸化水平(pYap)的表达量在两组间的差异均无统计学意义(P>0.05)。Taz的mRNA表达量在模型组和对照组分别为1.2167±0.0339和1.0133±0.1834,组间比较,差异有统计学意义(P<0.05);但其蛋白表达水平的组间差异无统计学意义(1.0497±0.3729和1.0014±0.0021,P>0.05)。结论先天性膈疝大鼠胎肺中未磷酸化的Yap的表达水平相对增加可能是导致胎肺成熟滞后、发育受阻的重要原因。

Objective To explore the expression of Hippo signaling pathway in lung tissue of fetal rats with congenital diaphragmatic hernia(CDH)and to explore the relationship between this pathway and pulmonary hypoplasia.Methods The CDH rat model was established with nitrofen.Left lung of fetal rats with simple diaphragmatic hernia in model group was selected and analyzed.The expressions of Lats1,Taz and Yap(pYap)in lung tissues were detected by Western blot and reverse transcription-polymerase chain reaction(RT-PCR)and compared with left lung tissues of fetal rats in normal control group.Results Lats1,Taz and Yap were expressed in bronchial,pulmonary epithelial cells and pulmonary artery walls of both model and normal fetal rats.The expression levels of Yap protein and its mRNA were significantly elevated in model group(2.3333±0.3675,1.2433±0.1033)than those in control group(1.2509±0.3886,0.9833±0.0650)(P<0.05).No inter-group statistical difference existed in the expression level of Lats1 or pYap(P>0.05).Although the mRNA expression levels of Taz were different(1.2167±0.0339,1.0133±0.1834),no inter-group statistical difference existed in the level of protein expression(1.0497±0.3729,1.0014±0.0021)(P>0.05).Conclusions The relative up-regulation of non-phosphorylated Yap may be an important cause for delayed fetal lung maturation and stunted development in fetal lungs of CDH rats.