NFAT5 directs hyperosmotic stress-induced fibrin deposition and macrophage infiltration via PAI-1 in endothelium

Although stress can significantly promote atherosclerosis, the underlying mechanisms are still not completely understood. Here we successfully unveiled that high salt-induced nuclear factor of activated T cells 5 (NFAT5) control the endothelial-dependent fibrinolytic activity and the inflammatory adhesion-related molecules expression through regulation of plasminogen activator inhibitor-1 (PAI-1). We first observed that high salt diets instigated the expression of NFAT5 and PAI-1 in the endothelium which brought about the fibrin deposition and macrophage infiltration in the atherosclerotic arteries of ApoE(-/-) mice. Overexpression of NFAT5 increased PAI-1-mediated antifibrinolytic activity and activated inflammatory adhesion-related genes in endothelial cells. Knockdown of NFAT5 by siRNA inhibited the expression of PAI-1, antifibrinolytic and adhesive molecules. Moreover, chromatin immunoprecipitation assay demonstrated that high salt intake significantly promoted the binding of NFAT5 to PAI-1 promoter (TGGAATTATTT) in endothelial cells. Our study identified that NFAT5 has great potential to activate the PAI-1-mediated fibrinolytic dysfunction and inflammatory cell adhesion, thus promoting high salt-induced atherosclerosis disease.