title: Glycated human serum albumin induces NF-κB activation and endothelial nitric oxide synthase uncoupling in human umbilical vein endothelial cells.
abstract: OBJECTIVE
  Non-enzymatic glycated proteins could mediate diabetes vascular complications, but the molecular mechanisms are unknown. Our objective was to find new targets involved in the glycated human serum albumin (gHSA)-enhanced extracellular reactive oxygen species (ROS) production in human endothelial cells.
  
  
  RESULTS
  Some nuclear factors and phosphorylation cascades were analysed. gHSA activated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), which up-regulated NOX4 and P22PHOX and enhanced ROS production. Pharmacological inhibition of NF-κB reversed gHSA-enhanced NOX4 expression and decreased gHSA-induced ROS production in extra- and intracellular spaces. The inhibition of activator protein-1 (AP-1) induced a rise in NOX4 and P22PHOX subunit expression and a down-regulation of endothelial nitric oxide synthase (eNOS). AP-1 inhibition also enhanced extracellular ROS production in the presence of serum albumin, but not with gHSA. These results were explained by the eNOS uncoupling induced by gHSA, also demonstrated in this study. Phosphatidylinositol 3-kinase or mitogen-activated protein kinase kinase 1/2 did not show to be involved in gHSA-induced ROS production.
  
  
  CONCLUSIONS
  All together, the results suggested that gHSA-enhanced ROS production in endothelium is mediated by: 1) NF-κB activation and subsequence up-regulation of NADPH oxidase, 2) eNOS uncoupling. AP-1, although is not directly affected by gHSA, is another target for regulating NADPH oxidase and eNOS expression in endothelial cells.
authors: Departamento de Medicina, Universidad de Santiago de Compostela; Servicio de Cardiología, Complejo Hospitalario Universitario de Santiago de Compostela and Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 A Coruña, Spain.
authors: Bruno K
authors: BK
authors: Rodiño-Janeiro
authors: Departamento de Medicina, Universidad de Santiago de Compostela; Servicio de Cardiología, Complejo Hospitalario Universitario de Santiago de Compostela and Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 A Coruña, Spain.
authors: Beatriz
authors: B
authors: Paradela-Dobarro
authors: Departamento de Medicina, Universidad de Santiago de Compostela; Servicio de Cardiología, Complejo Hospitalario Universitario de Santiago de Compostela and Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 A Coruña, Spain.
authors: Sergio
authors: S
authors: Raposeiras-Roubín
authors: Unidad de Medicina Materno-Fetal, Servicio de Obstetricia, Complejo Hospitalario Universitario de Santiago de Compostela, 15706 A Coruña, Spain.
authors: Mercedes
authors: M
authors: González-Peteiro
authors: Departamento de Medicina, Universidad de Santiago de Compostela; Servicio de Cardiología, Complejo Hospitalario Universitario de Santiago de Compostela and Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 A Coruña, Spain.
authors: José R
authors: JR
authors: González-Juanatey
authors: Departamento de Medicina, Universidad de Santiago de Compostela; Servicio de Cardiología, Complejo Hospitalario Universitario de Santiago de Compostela and Instituto de Investigación Sanitaria de Santiago (IDIS), 15706 A Coruña, Spain. Electronic address: ezequiel.alvarez.castro@gmail.com.
authors: Ezequiel
authors: E
authors: Álvarez
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003925:Diabetic Angiopathies / Q000378:metabolism* / Q000473:pathology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D017127:Glycation End Products, Advanced; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology; D006801:Humans; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D052002:NF-kappa B p50 Subunit / Q000819:agonists* / Q000037:antagonists & inhibitors / Q000378:metabolism; D009569:Nitric Oxide / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D012709:Serum Albumin / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000075462:Serum Albumin, Human; D013481:Superoxides / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D000093423:Glycated Serum Albumin
chemical_list: C422455:ALB protein, human; D004791:Enzyme Inhibitors; D017127:Glycation End Products, Advanced; D052002:NF-kappa B p50 Subunit; C489548:NFKB1 protein, human; D011500:Protein Synthesis Inhibitors; D017382:Reactive Oxygen Species; D012709:Serum Albumin; D018808:Transcription Factor AP-1; D013481:Superoxides; D009569:Nitric Oxide; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; C498910:NOX4 protein, human; C086986:CYBA protein, human; D000075462:Serum Albumin, Human; D000093423:Glycated Serum Albumin
keywords: Amadori adducts; Endothelial dysfunction; Glycated albumin; NF-κB; Reactive oxygen species