High glucose condition increases NADPH oxidase activity in endothelial microparticles that promote vascular inflammation.

AIMS Diabetes is a major risk factor for cardiovascular diseases. Circulating endothelial microparticles (EMP) are increased in diabetic patients, but their potential contribution in atherogenesis is unclear. We sought to determine the role of EMP derived under high glucose conditions in the development of atherosclerosis. METHODS AND RESULTS EMP were generated from human coronary endothelial cells (HCAEC) exposed to high glucose concentrations in order to mimic diabetic conditions. These EMP were defined as 'injured' EMP (iEMP) and their effects were compared with EMP generated from 'healthy' untreated HCAEC. iEMP injection significantly impaired endothelial function in ApoE(-/-) mice compared with EMP and vehicle treatment. Immunofluorescent experiments showed increased macrophage infiltration and adhesion protein expression in atherosclerotic lesions of iEMP-treated ApoE(-/-) mice compared with controls. To further investigate the underlying mechanism of iEMP-induced vascular inflammation, additional in vitro experiments were performed. iEMP, but not EMP, induced activation of HCAEC in a time- and dose-dependent manner and increased monocyte adhesion. Further experiments demonstrated that iEMP induced activation of HCAEC by phosphorylation of p38 into its biologically active form phospho-p38. Inhibition of p38 activation abrogated iEMP-dependent induction of adhesion proteins and monocyte adhesion on HCAEC. Moreover, we could demonstrate that iEMP show increased NADPH oxidase activity and contain significantly higher level of reactive oxygen species (ROS) than EMP. iEMP triggered ROS production in HCAEC and thereby activate p38 in an ROS-dependent manner. CONCLUSION High glucose condition increases NADPH oxidase activity in endothelial microparticles that amplify endothelial inflammation and impair endothelial function by promoting activation of the endothelium. These findings provide new insights into the pathogenesis of diabetes-associated atherosclerosis.

[1]  L. Ragolia,et al.  Circulating Endothelial Microparticles in Diabetes Mellitus , 2010, Mediators of inflammation.

[2]  K. Fukudome,et al.  Microparticle-associated endothelial protein C receptor and the induction of cytoprotective and anti-inflammatory effects , 2009, Haematologica.

[3]  P. Libby,et al.  Inflammation and Atherosclerosis , 2002, Circulation.

[4]  Y. Ikeda,et al.  Function and role of microparticles in various clinical settings. , 2008, Thrombosis research.

[5]  V. Paradis,et al.  Abnormal plasma microparticles impair vasoconstrictor responses in patients with cirrhosis. , 2012, Gastroenterology.

[6]  G. King,et al.  Glucose or diabetes activates p38 mitogen-activated protein kinase via different pathways. , 1999, The Journal of clinical investigation.

[7]  F. Dignat-George,et al.  Interaction of endothelial microparticles with monocytic cells in vitro induces tissue factor-dependent procoagulant activity. , 2002, Blood.

[8]  S. Nomura.  Statin and endothelial cell-derived microparticles , 2008, Thrombosis and Haemostasis.

[9]  T. Chavakis,et al.  Developmental Endothelial Locus-1 (Del-1) Mediates Clearance of Platelet Microparticles by the Endothelium , 2012, Circulation.

[10]  G. Nickenig,et al.  Monocytic microparticles promote atherogenesis by modulating inflammatory cells in mice , 2012, Journal of cellular and molecular medicine.

[11]  C. Weber,et al.  Microparticles: Protagonists of a Novel Communication Network for Intercellular Information Exchange , 2010, Circulation research.

[12]  K. Pritchard,et al.  Comparative proteomic analysis of PAI‐1 and TNF‐alpha‐derived endothelial microparticles , 2008, Proteomics.

[13]  P. Brunet,et al.  Endothelial-derived microparticles: Biological conveyors at the crossroad of inflammation, thrombosis and angiogenesis , 2010, Thrombosis and Haemostasis.

[14]  A. Schmidt,et al.  Human Vascular Endothelial Cells: A Model System for Studying Vascular Inflammation in Diabetes and Atherosclerosis , 2011, Current diabetes reports.

[15]  Chantal M Boulanger,et al.  Microparticles From Human Atherosclerotic Plaques Promote Endothelial ICAM-1–Dependent Monocyte Adhesion and Transendothelial Migration , 2011, Circulation research.

[16]  M. Hristov,et al.  Delivery of MicroRNA-126 by Apoptotic Bodies Induces CXCL12-Dependent Vascular Protection , 2009, Science Signaling.

[17]  R. Cohen,et al.  Elevated glucose impairs endothelium-dependent relaxation by activating protein kinase C. , 1991, The Journal of clinical investigation.

[18]  J. Blenis,et al.  ERK and p38 MAPK-Activated Protein Kinases: a Family of Protein Kinases with Diverse Biological Functions , 2004, Microbiology and Molecular Biology Reviews.

[19]  M. Brownlee.  Biochemistry and molecular cell biology of diabetic complications , 2001, Nature.

[20]  E. Araki,et al.  Activation of AMP-activated protein kinase reduces hyperglycemia-induced mitochondrial reactive oxygen species production and promotes mitochondrial biogenesis in human umbilical vein endothelial cells. , 2006, Diabetes.

[21]  Jerry L. Adams,et al.  A protein kinase involved in the regulation of inflammatory cytokine biosynthesis , 1994, Nature.

[22]  Achilleas S. Frangakis,et al.  Atheroprotective communication between endothelial cells and smooth muscle cells through miRNAs , 2012, Nature Cell Biology.

[23]  Christian Weber,et al.  Microparticles: Protagonists of a Novel Communication Network for Intercellular Information Exchange , 2010, Circulation research.

[24]  P. Massin,et al.  Increased Vitreous Shedding of Microparticles in Proliferative Diabetic Retinopathy Stimulates Endothelial Proliferation , 2009, Diabetes.

[25]  R. Nieuwland,et al.  Phospholipid composition of in vitro endothelial microparticles and their in vivo thrombogenic properties. , 2008, Thrombosis research.

[26]  Richard J Sciotti,et al.  Enhanced basal activation of mitogen-activated protein kinases in adipocytes from type 2 diabetes: potential role of p38 in the downregulation of GLUT4 expression. , 2003, Diabetes.

[27]  A. Simon,et al.  Microparticles, Vascular Function, and Atherothrombosis , 2011, Circulation research.

[28]  E. Latz,et al.  Endothelial Microparticle Uptake in Target Cells Is Annexin I/Phosphatidylserine Receptor Dependent and Prevents Apoptosis , 2012, Arteriosclerosis, thrombosis, and vascular biology.

[29]  Link,et al.  UvA-DARE ( Digital Academic Repository ) Endothelial cell-derived microparticles , 2007 .

[30]  L. Horstman,et al.  Endothelial cells release phenotypically and quantitatively distinct microparticles in activation and apoptosis. , 2003, Thrombosis research.