Regulation of Calcium Homeostasis by PIEZO1 Drives NETosis and Fibrosis in Bronchopulmonary Dysplasia.

Bronchopulmonary dysplasia (BPD) is a chronic lung disease primarily affecting preterm infants, characterised by impaired alveolar development and persistent inflammation, particularly associated with ventilator-induced lung injury due to mechanical ventilation. In this study, we performed an integrated bioinformatic analysis of multiple datasets (GSE108754 and GSE39840) and identified 203 differentially expressed genes (DEGs) between BPD and control samples. Functional enrichment analysis revealed significant involvement in cytokine-mediated signalling, response to lipopolysaccharide and regulation of interferon-beta production. Using machine learning algorithms (LASSO, SVM-RFE and Random Forest), we identified three hub genes (IL6, TFRC and PIEZO1) with high diagnostic accuracy for BPD. Immune infiltration analysis indicated altered immune cell proportions in BPD, with PIEZO1 expression positively correlated with neutrophil infiltration. Experimental validation confirmed elevated NETosis markers (PADI4, MPO, dsDNA) in BPD patients and further demonstrated that PIEZO1 overexpression promotes NET formation via calcium overload, which was inhibited by verapamil. Additionally, using a co-culture system, we showed that PIEZO1-induced NETosis exacerbates pulmonary fibrosis in lung epithelial cells. These findings highlight PIEZO1 as a key regulator of NETosis in BPD and a promising therapeutic target for mitigating lung injury and fibrosis.