Effects and mechanism of heat shock protein 70 induced by rhubarb on lung development of bronchial lung in newborn rats / 国际儿科学杂志

ABSTRACT

Objective To establish SD rat model of bronchopulmonary dysplasia(BPD) and investigate the influence and mechanism of heat shock protein 70 (HSP70) on the lung tissue with BPD.Methods One hundred and twenty new born SD rats were randomly equally divided into three groups,including blank-control group,bronchopulmonary dysplasia group,rhubarb intervention group (bronchopulmonary dysplasia rats treated with rhubarb).On the 7th,14th and 21th day,10 rats were euthanasiaed after weighted of each group.Histopathology of pulmonary,hematoxylin and eosin(HE)and the expression of HSP70 in the right lung were observed respectively.Results Compared with the rat of blank-control group,the rat weight of BPD group was significantly decreased at the same time point(P ＜0.01).On the 7th day,the alveolar cavity increased,alveolar wall became thin,and pulmonary interstitial cells increased in the rat of BPD group given oxygen.By 21 days,the normal structure of the alveoli disappeared,the diameter of the alveolar cavity enlarged,the number of alveoli significantly reduced,the alveolar fusion was large,and the alveolar space became thickness,and massive of interstitial cells hyperplasia.While,in the rhubarb intervention group,the lung tissue structure kept integrity,the size of the alveoli uniform.During 14 to 21 days,the integrity of lung structure and the uniform size alveoli still existed,and alveolar septa was thin.In immunohistochemical staining and western blotting experiments,the expression of HSP70 in rhubarb intervention group increased gradually with the increase of age,which was significantly different from control group(P ＜0.01).However,the expression of HSP70 in BPD group had not significant change on the 7th,14th and 21th days(P ＞0.05).Compared with rhubarb intervention group,the expression of HSP70 in the BPD group significantly decreased on the 14th and 21th day(P ＜0.01) respectively.Conclusion Rhubarb could protect the injured lung tissue by increasing the expression of HSP70.