Effect Of Inflammation Induced MAPK Apoptosis Pathway On CDH Lung Tissue

Background:Congenital diaphragmatic hernia（CDH）is a congenital embryonic malformation caused by incomplete growth of fetal diaphragm and abnormal development of lung.The incidence rate is 2.5?-5.7?,and the total mortality rate is45%-75%.With the continuous progress of CDH research,neonatal postpartum support treatment and diaphragm repair surgery are relatively mature.However,its pulmonary dysplasia and persistent pulmonary hypertension are still difficult to correct,which is also the main cause of neonatal death.Objective:The relationship between the changes of ASK1/MAPK apoptosis pathway induced by inflammation and the abnormal development of fetal lung were investigated in CDH animal model.Method:SPF SD rats of 9.5 days pregnant were randomly divided into blank control group（Control group）,diaphragmatic hernia group（CDH group）and CDH +sildenafil intervention group（CDH+S group）after the intervention of the nitrofen and sildenafil.RT-q PCR was used to detect the relative m RNA expression of ASK1/MAPK pathway in fetal lung.WB was used to detect the protein expression of the p-ASK1,JNK and p38α.Fetal lung sections were analyzed by HE,and the protein expression location of the ASK1,JNK and p38α were located by IHC.Result:50 live fetuses of 4 pregnant rats in Control group,84 live fetuses of 6 pregnant rats in CDH group and 37 live fetuses of 4 pregnant rats in CDH+S group were successfully obtained.HE staining showed that pulmonary dysplasia and vascular remodeling in CDH group compared with Control group,the fetal lung in CDH+S group was significantly improved compared with CDH group.IHC showed the protein expression of the ASK1,P38α and JNK were expressed in all groups,It was located at the edge of lung lobe,trachea,tracheal cartilage,surrounding connective tissue,hypoplastic whole lung lobe and some blood vessels.RT-q PCR,the relative m RNA expression levels of ASK1 and upstream TGFBR2,DAXX,downstream p38α,JNK was positively correlated,（r=0.6323,p<0.0001;r=0.7754,p<0.0001;r=0.8144,p<0.0001;r=0.2837,p=0.0459）.The changes of TGFBR2-DAXX-ASK1-P38α/JNK m RNA were correlated.The DAXX m RNA of CDH group and CDH +S group were higher than Control group.（Control3.92±0.79/CDH 5.01±1.63/CDH+S 4.97±1.07;p<0.05）.The ASK1 m RNA in CDH group was significantly higher than that in Control group,（Control 4.51±1.04/CDH6.8±3.16/CDH+S 5.38±2.05;p<0.05）;The MKK3 m RNA of the CDH+S group was higher than that of Control group and CDH group,（Control 2.49±0.44/CDH2.42±0.51/CDH+S 2.94±0.80;p<0.05）;The MKK4 m RNA of the CDH +S group was significantly higher than that of Control group and CDH group,（Control11.01±2.72/CDH 13.11±4.14/CDH+S 16.27±4.35;p<0.05）.WB:Compared with the Control group,the expression of JNK protein in CDH group increased significantly,（Control / CDH / CDH +S,1.00 ±0.50/3.32 ± 1.40/2.28 ±0.73;p < 0.05）.Conclusion:In nitrofen induced animal model,The up regulation of TGFBR2-DAXX-ASK1-JNK/p38α access of fetal lung may be related to pulmonary dysplasia and pulmonary hypertension.