The role of α1AMP-activated protein kinase (α1AMPK) in vascular dysfunctions induced by sepsis

Abstract

Sepsis is a pathological circumstance whose outcome is associated with organ dysfunction and death. Vascular hyperpermeability and haemostasis impairment, both play a key role in the onset of organ failure. Our previous work highlighted the protective role of α1AMPK against sepsis-induced hyperpermeability. However, the impact of α1AMPK on haemostasis has never been investigated in this condition. This study aims to characterize the interaction of α1AMPK with hemostasis in sepsis. C57BL6 J mice and α1AMPK wild-type (WT) and knock-out (KO) mice were challenged with intraperitoneal injection of lipopolysaccharide (LPS) from Escherichia coli O55B5 (10 mg.kg-1) during 6 hours. Plasmatic markers of coagulation, platelet and NETosis activation were measured by ELISA and membrane markers of platelet activation were analysed by flow cytometry. The dsDNA analysis of NETosis was performed by fluorometry. Ex vivo platelets activation was assessed by flow cytometry on platelets α1AMPK WT and KO, incubated in a medium with 5 μg/mL of LPS. In C57BL6 J mice, haemostasis was activated 6 hours after LPS administration, as reflected by the increase in fibrinogen, plasminogen activator inhibitor and tissue plasminogen activator. In addition, platelets isolated from LPS-treated mice were activated as demonstrated by the increased exposure of CD62P and αIIbβIII on platelet surface and soluble CD62P detection in plasma. Finally, we measured a significant increase in myeloperoxidase, neutrophil elastase and plasmatic dsDNA, all markers of NETosis. Same parameters were measured in α1AMPK WT and KO mice. We brought out an increase of fibrinolysis impairment and heightened a trend of NETosis in α1AMPK undergoing sepsis. Furthermore, platelets of α1AMPK KO mice exhibited a more important activation ex vivo, in response to LPS. These results suggest that α1AMPK is involved in the regulation of hemostasis disturbances following sepsis.