Dual Cardioprotective Roles of FOXF1: Attenuation of DNA Damage in Cardiomyocytes and Restraint of Leukocyte Extravasation via Endothelial Barrier Preservation

Myocardial ischemia-reperfusion injury (MIRI) drives oxidative DNA damage in cardiomyocytes and triggers sterile inflammation, leading to leukocyte infiltration and microvascular dysfunction. Preservation of endothelial barrier integrity is crucial for limiting inflammatory cell trafficking and mitigating MIRI. In this work, FOXF1 was identified as a significantly upregulated gene in MIRI mouse myocardial tissues by mRNA-sequencing. In vivo, AAV9-mediated FOXF1 overexpression markedly improved cardiac function, reduced infarct size, and attenuated cardiomyocyte apoptosis and leukocyte infiltration after MIRI. Mechanistically, FOXF1 overexpression attenuated DNA damage in MIRI mice and oxygen-glucose deprivation/reoxygenation (OGD/R) treated HL-1 cells, which was associated with stabilization of the Fanconi anemia (FA) core complex. Concurrently, overexpression of FOXF1 upregulated VE-cadherin in cardiac endothelial cells (ECs) and inhibited the levels of Ly6G and pro-inflammatory adhesion molecules. The protective effect of FOXF1 upregulation on the endothelial barrier integrity was also confirmed in vitro, as evidenced by reduced hyperpermeability and leukocyte transmigration under OGD/R conditions. Further mRNA sequencing, combined with chromatin immunoprecipitation and dual-luciferase reporter assays, revealed that FOXF1 directly binds to the promoter region of CDH2 (Cadherin-2) and transcriptionally activates its expression in ECs. Overexpression of CDH2 reduced hyperpermeability and leukocyte transmigration of ECs under OGD/R conditions. Suppression of CDH2 reversed the resistance effects of FOXF1 overexpression on endothelial permeability and leukocyte transmigration. Collectively, our findings suggest that FOXF1 confers cardioprotection against MIRI through two distinct but complementary mechanisms: attenuating DNA damage in cardiomyocytes and transcriptionally upregulating CDH2 to preserve endothelial barrier integrity, thereby inhibiting leukocyte infiltration.