Endothelial YAP Mediates Hyperglycemia-Induced Platelet Hyperactivity and Arterial Thrombosis

Hyperglycemia-a symptom that characterizes diabetes-is highly associated with atherothrombotic complications. However, the underlying mechanism by which hyperglycemia fuels platelet activation and arterial thrombus formation is still not fully understood.

The profiles of polyunsaturated fatty acid metabolites in the plasma of patients with diabetes and healthy controls were determined with targeted metabolomics. FeCl₃-induced carotid injury model was used to assess arterial thrombus formation in mice with endothelial cell (EC)-specific YAP (yes-associated protein) deletion or overexpression. Flow cytometry and clot retraction assay were used to evaluate platelet activation. RNA sequencing and multiple biochemical analyses were conducted to unravel the underlying mechanism.

The plasma PGE₂ (prostaglandin E₂) concentration was elevated in patients with diabetes with thrombotic complications and positively correlated with platelet activation. The PGE₂ synthetases COX-2 (cyclooxygenase-2) and mPGES-1 (microsomal prostaglandin E synthase-1) were found to be highly expressed in ECs but not in other type of vessel cells in arteries from both patients with diabetes and hyperglycemic mice, compared with nondiabetic individuals and control mice, respectively. A combination of RNA sequencing and ingenuity pathway analyses indicated the involvement of YAP signaling. EC-specific deletion of YAP limited platelet activation and arterial thrombosis in hyperglycemic mice, whereas EC-specific overexpression of YAP in mice mimicked the prothrombotic state of diabetes, without affecting hemostasis. Mechanistically, we found that hyperglycemia/high glucose-induced endothelial YAP nuclear translocation and subsequently transcriptional expression of COX-2 and mPGES-1 contributed to the elevation of PGE₂ and platelet activation. Blockade of EP3 (prostaglandin E receptor 3) activation by oral administration of DG-041 reversed the hyperactivity of platelets and delayed thrombus formation in both EC-specific YAP-overexpressing and hyperglycemic mice.

Collectively, our data suggest that hyperglycemia-induced endothelial YAP activation aggravates platelet activation and arterial thrombus formation via PGE₂/EP3 signaling. Targeting EP3 with DG-041 might be therapeutic for diabetes-related thrombosis.