Effect of Transforming Growth Factor-β_1 in a Neonatal Mouse Bronchopulmonary Dysplasia Model Induced by Moderate Hyperoxia Exposure

Objective:To study the effect and injuries of moderate hyperoxia exposure(60% O2) on a neonatal mouse development to observe the effect of TGF-β1 on the lung injuries of the neonatal mouse bronchopulmonary dysplasia.Methods: Thirty neonatal female KM mice were randomly divided into an experiment group and a control group(n=15).The control group was put in the air(FiO2 0.21) and the experiment group was put in the sealed oxygen box(FiO2 0.6) to prepare the model of the neonatal female mouse bronchopulmonary dysplasia induced by moderate hyperoxia,record the mouse body weight at the 2nd,7th,14th,21st,28th days after inhaling oxygen and observe the changes of pulmonary histopathology of different time points by HE staining and the expression levels of TGF-β1 protein by immunohistochemistry.Results: The body weight of the mouse in the experiment group was significantly reduced after 7 days of inhaling oxygen and the structure of normal alveolar disappeared,alveolar was fused and the alveolar intervals were thickened under the HE staining.The expression of TGF-β1 increased after 72 hours of hyperoxia exposure and the expression of TGF-β1 would continuously increase with the prolongation of inhaling oxygen.Conclusion:Oxygen inhalation of sustainable higher concentration may result in growth failure and pulmonary alveolarization block and appear pulmonary changes that is similarities to human bronchopulmonary dysplasia.TGF-β1 plays an important roles in development and sustainment of the pulmonary fibrosis(PF).