title: Advanced glycation end products upregulate lysyl oxidase and endothelin-1 in human aortic endothelial cells via parallel activation of ERK1/2-NF-κB and JNK-AP-1 signaling pathways.
abstract: Endothelial dysfunction involves deregulation of the key extracellular matrix (ECM) enzyme lysyl oxidase (LOX) and the vasoconstrictor protein, endothelin-1 (ET-1), whose gene expression can be modulated by the transcriptional activators nuclear factor kappa B (NF-κB) and activator protein-1 (AP-1). Advanced glycation end products (AGEs) present an aggravating factor of endothelial dysfunction which upon engagement to their receptor RAGE induce upregulation of mitogen-activated protein kinases (MAPKs), leading to NF-κB and AP-1 potentiation. We hypothesized that AGEs could induce NF-κΒ- and AP-1-dependent regulation of LOX and ET-1 expression via the AGE/RAGE/MAPK signaling axis. Western blot, real-time qRT-PCR, FACS analysis and electrophoretic mobility-shift assays were employed in human aortic endothelial cells (HAECs) following treatment with AGE-bovine serum albumin (AGE-BSA) to investigate the signaling pathway towards this hypothesis. Furthermore, immunohistochemical analysis of AGEs, RAGE, LOX and ET-1 expression was conducted in aortic endothelium of a rat experimental model exposed to high- or low-AGE content diet. HAECs exposed to AGE-BSA for various time points exhibited upregulation of LOX and ET-1 mRNA levels in a dose- and time-dependent manner. Exposure of HAECs to AGE-BSA also showed specific elevation of phospho(p)-ERK1/2 and p-JNK levels in a dose- and time-dependent fashion. AGE administration significantly increased NF-κΒ- and AP-1-binding activity to both LOX and ET-1 cognate promoter regions. Moreover, LOX and ET-1 overexpression in rat aortic endothelium upon high-AGE content diet confirmed the functional interrelation of these molecules. Our findings demonstrate that AGEs trigger NF-κΒ- and AP-1-mediated upregulation of LOX and ET-1 via the AGE/RAGE/MAPK signaling cascade in human endothelial cells, thus contributing to distorted endothelial homeostasis by impairing endothelial barrier function, altering ECM biomechanical properties and cell proliferation.
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece.
authors.forename: Christos
authors.initials: C
authors.lastname: Adamopoulos
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece.
authors.forename: Christina
authors.initials: C
authors.lastname: Piperi
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece.
authors.forename: Antonios N
authors.initials: AN
authors.lastname: Gargalionis
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece.
authors.forename: Georgia
authors.initials: G
authors.lastname: Dalagiorgou
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece.
authors.forename: Eliana
authors.initials: E
authors.lastname: Spilioti
authors.affiliation: First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527, Athens, Greece.
authors.forename: Penelope
authors.initials: P
authors.lastname: Korkolopoulou
authors.affiliation: Third Department of Internal Medicine, Medical School, National and Kapodistrian University of Athens, 'Sotiria' Hospital, 11527, Athens, Greece.
authors.forename: Evanthia
authors.initials: E
authors.lastname: Diamanti-Kandarakis
authors.affiliation: Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75, M. Asias Street, 11527, Athens, Greece. papavas@med.uoa.gr.
authors.forename: Athanasios G
authors.initials: AG
authors.lastname: Papavassiliou
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology / Q000378:metabolism*; D002460:Cell Line; D042783:Endothelial Cells / Q000378:metabolism*; D019332:Endothelin-1 / Q000096:biosynthesis*; D004730:Endothelium, Vascular / Q000378:metabolism; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000502:physiology*; D016328:NF-kappa B / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D008249:Protein-Lysine 6-Oxidase / Q000096:biosynthesis*; D051381:Rats; D017208:Rats, Wistar; D000067759:Receptor for Advanced Glycation End Products / Q000378:metabolism; D051127:Scavenger Receptors, Class E / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism; D015533:Transcriptional Activation
chemical_list: D019332:Endothelin-1; D017127:Glycation End Products, Advanced; D016328:NF-kappa B; C495137:OLR1 protein, human; D000067759:Receptor for Advanced Glycation End Products; D051127:Scavenger Receptors, Class E; D018808:Transcription Factor AP-1; D008249:Protein-Lysine 6-Oxidase; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases
keywords: AGEs; Endothelial dysfunction; Endothelin-1; Lysyl oxidase; RAGE; Signaling pathways