Programming to S1PR1+ Endothelial Cells Promotes Restoration of Vascular Integrity.
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ABSTRACT:
SUBMITTER: Akhter MZ
PROVIDER: S-EPMC8273089 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Increased endothelial permeability and failure to repair is the hallmark of several vascular diseases including acute lung injury (ALI). However, little is known about the intrinsic pathways that activate endothelial cell (EC) regenerative programs and thereby tissue repair. Studies have invoked a crucial role of sphingosine-1-phosphate (S1P) in resolving endothelial hyperpermeability through activation of the G-protein coupled receptor, sphingosine-1-phosphate receptor 1 (S1PR1). Here, we addressed mechanisms of generation of S1PR1+ EC, which may prevent endothelial injury. Studies were made using inducible EC-S1PR1-/- (iEC-S1PR1-/-) mice and S1PR1-GFP reporter mice to trace the generation of S1PR1+ EC. We observed in a mouse model of endotoxemia that S1P generation induced the programming of S1PR1lo to S1PR1+ EC, which comprised 80% of lung EC. The transition of these cells was required for reestablishing the endothelial barrier. We also observed that conditional deletion of S1PR1 in EC increased vascular permeability. RNA-seq analysis of S1PR1+ EC showed enrichment of genes regulating S1P synthesis and transport, sphingosine kinase 1 (SPHK1) and SPNS2, respectively. The activation of transcription factors EGR1 and STAT3 were essential for transcribing SPHK1 and SPNS2, respectively, to increase S1P production that served to amplify S1PR1+ EC transition. Transplantation of S1PR1+ EC into injured lung vasculature restored endothelial integrity. Our findings show that generation of a S1PR1+ EC population activates the endothelial regenerative program mediating vascular endothelial repair, thus raising the possibility of harnessing this pathway to restore vascular homeostasis in inflammatory injury.
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Project description:Programming to S1PR1+ Endothelial Cell Promotes Restoration of Lung Vascular Integrity
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