miR-3202 inhibits bronchopulmonary dysplasia-mediated apoptosis and oxidative stress in bronchial epithelial cells via targeting RAG1

Background

BPD is a refractory disease affecting preterm infants with alveolar dysplasia and declined pulmonary function. However, the molecular mechanism underlying BPD is largely unknown. To explore the pathogenic mechanism of BPD and to facilitate better diagnosis and treatment of this disease.

Method

The DEMs and DEGs in BPD vs. Control samples from the miRNA expression data in GSE108754 and mRNA expression data in the GSE108755 were screened, followed by the construction of the miRNA-mRNA regulatory network. DEGs PPI network and hub DEGs analysis were constructed by using the STRING database and Cytoscape software. Functional and pathway enrichment analyses were then performed for these DEGs and DEMs based on the ClusterProfiler package in the R and the miRWalk database. The k-mean algorithm is used to perform clustering analysis of DEGs. Cellular experiments (flow cytometry, western blot, RT-PCR, dual-luciferase reporter assay) were used to validate the results of bioinformatics.

Results

We obtained 20 DEMs and 262 DEGs. A 15 DEMs-11 DEGs regulatory network was constructed. miR-3202-RAG1 is a core sub-network. Hyperoxia induced a cell model of BPD. The upregulation of RAG1 and downregulation of miR-3202 were observed in BPD cells. Furthermore, siRNA targeting RAG1 was transfected into BEAS-2B cells to inhibit its expression and miR-3202 mimics was transfected into the cells to increase its expression. Inhibition of RAG1 and elevation of miR-3202 inhibit cell apoptosis and reduce ROS level caused by hyperoxia. A double-luciferase reporter assay revealed that miR-3202 directly targets RAG1.

Conclusion

The miRNA-3202/RAG1 axis contributes into BPD-induced cell apoptosis and ROS production. The present study provides a probable target for the treatment of BPD.