Effects of prenatal tetrandrine treatment on the expression of Kruppel-like factor 5 and Survivin in the lung of congenital diaphragmatic hernia rat model induced by nitrofen

Abstract

Objective: To investigate the effect of prenatal administration of tetrandrine on the expression of Kruppel-like factors 5 (KLF5) and Survivin in the lung of congenital diaphragmatic hernia (CDH) rat model. Methods: This experiment took simple random group method, 11 pregnant SD rats were randomly divided into three groups: normal control group (group NC, 3), model control group (group MC, 4), model+ tetrandrine group (group MT, 4). The rats in group MC and MT were given gavage administration with 125 mg nitrofen to induce CDH and the rats in group MT were administered with 30 mg/kg tetrandrine for three days (gestational age of 18.5, 19.5 and 20.5 d). All fetuses were delivered by caesarian section at the gestational age of 21.5 d to observe the formation of diaphragmatic hernia in 3 groups and to record the ratio of lung weight and body weight (Lw/Bw). The maturity situation of fetal lung tissue was evaluated by hematoxylin-eosin staining (HE staining). The expression of KLF5 and Survivin were detected by immune-histochemical staining and quantitatively analyzed by Western blotting methods.Single factor analysis of variance was taken among 3 groups to compare means of variables and the chi-square test was used to compare the difference of birth defect rates. Results: There was significant difference in CDH incidence between group MC [56.1%(37/66)] and MT[50.0%(28/56)](χ(2)=122.00, P<0.05). There was no significant difference in Lw/Bw among the three groups (F=0.985, P=0.376). The HE staining showed that pulmonary vascular-related and pulmonary alveolar-related developmental indexes in group MC were lower than those in the group NC, and those in the group MT were between the two groups.In addition, immunohistochemical staining showed that the average optical density (AOD) of KLF5 in group NC, MC, MT was 0.194 8±0.007 4, 0.212 1±0.004 9 and 0.192 7±0.001 9, respectively (F=14.53, P=0.002); and AOD of Survivin was 0.185 2±0.008 7, 0.209 2±0.003 6 and 0.192 8±0.007 5, respectively (F=12.31, P=0.003). The expression level of Survivin was positively correlated with that of KLF5 (r=0.993, P=0.039). Western blotting revealed that there were remarkable difference in the protein expression of KLF5 and Survivin among the three groups (F=4.29, 10.13, both P<0.05). Conclousions: Prenatal gavage of tetrandrine to CDH rats induced by nitrofen promotes the development of fetal lung parenchyma and vascellum, and reduces the expression level of KLF5 and Survivin protein in fetal lung, which may be the mechanism of tetrandrine in improving lung hypoplasia of CDH.