Abstract Rationale Aberrant repair following airway injury is a major cause of airway stenosis and restenosis, posing significant clinical risks, and its molecular mechanisms remain incompletely understood. Metabolic reprogramming is recognized as playing an important role in the repair microenvironment. Lactate, a glycolytic metabolite, can regulate gene transcription via histone lactylation. However, whether lactylation modification is involved in angiogenesis and structural remodeling after airway injury has not been reported. This study aims to elucidate the role of H3K18 lactylation in airway fibroblasts during angiogenesis and its downstream signaling mechanisms, providing new therapeutic targets for aberrant airway injury repair. Methods H3K18la levels were detected in primary airway fibroblasts treated with lactate, and the regulatory mechanisms were investigated using MCT1 and P300 inhibitors. A fibroblast-endothelial cell co-culture system was established to assess the effects of lactylation modification on endothelial cell proliferation, migration, and tube formation. Combined CUT&Tag and RNA sequencing (RNA-seq) were used to screen target genes of H3K18la, and biological function was verified through CCL2/CCR2 signaling pathway intervention experiments. The glycolytic inhibitor 2-DG and animal models were used to validate the findings in vivo. Results Lactate accumulation, H3K18la levels, and vascular density were significantly increased in tissues after airway injury (Vascular density: Normal group 1.5%, Model group 3.9%). The glycolytic inhibitor 2-DG suppressed these changes and alleviated airway stenosis (Stenosis rate: Model group 68.6%, 2-DG group 35.5%). Lactate entered fibroblasts via the monocarboxylate transporter MCT1, induced upregulation of P300-mediated H3K18 lactylation, and enhanced the pro-angiogenic capacity of fibroblasts. Integrated CUT&Tag and RNA-seq analysis revealed that H3K18la was enriched at the CCL2 promoter region and upregulated its transcription. Fibroblast-secreted CCL2 activated endothelial cell proliferation, migration, and tube formation via the CCR2 receptor. Conclusion This study reveals the critical role of the “Lactate-H3K18la- CCL2/ CCR2” signaling axis in airway fibroblasts in promoting angiogenesis and aberrant repair following airway injury. This finding links metabolic-epigenetic regulation to vascular regeneration for the first time, suggesting H3K18 lactylation as a potential therapeutic target for intervening in airway restenosis. This abstract is funded by: None
Xia et al. (Fri,) studied this question.