Supplementary Figure 1 - 3

For in vitro studies, murine lung epithelial cells (MLE-12) were cultured in DMEM/F12 medium supplemented with 10% FBS. To model hyperoxic injury, cells were exposed to 85% O₂ (HYX group), with 21% O₂ as the control (NOX group). To investigate the role of the STING signaling pathway, cells were treated with the specific inhibitor H151 (0.5 µM), divided into: NOX, NOX+H151, HYX, HYX+H151. For in vivo studies, newborn Sprague-Dawley rats were randomly assigned to four groups: normoxia (NOX), normoxia + H151 (NOX+H151), hyperoxia (HYX, 85% O₂), and hyperoxia + H151 (HYX+H151). H151 (4 mg/kg/day) was administered via intraperitoneal injection.Key techniques employed include: Immunofluorescence (IF) staining (to detect the localization and expression of proteins includingP21, P16, Ki67, γH2A.X, TFAM, VDAC1, DNA), Western Blot (to analyze the expression levels of proteins such as RAGE, SP-C, BAX), SA-β-gal)activity assay, and JC-1 staining flow cytometry.Imaging analysis was performed using ImageJ software (e.g., colocalization analysis). Protein bands were captured using a Tanon 5200 imaging system.All animal experimental protocols were approved by the Animal Care and Use Committee of Xinhua Hospital (Approval No.: XHEC-NSFC-2022-090).