title: Angiotensin-converting-enzyme inhibition counteracts angiotensin II-mediated endothelial cell dysfunction by modulating the p38/SirT1 axis.
abstract: OBJECTIVE
  Oxidative stress has been linked to endothelial dysfunction and angiotensin II stimulates the reactive oxygen species production contributing to several cardiovascular diseases. We have studied the chain of events induced by angiotensin-converting-enzyme (ACE) activation in vascular umbilical vein endothelial cells (HUVECs) by using an ACE inhibitor such as zofenoprilat.
  
  
  METHODS
  We used specific assay to measure the superoxide anion production, tetrazolium bromide (MTT) assay for cell viability, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay for cell apoptosis, and western blot for protein analysis in the study.
  
  
  RESULTS
  Zofenoprilat counteracts the superoxide anion production and cell apoptosis induced by angiotensin I treatment by blocking the extrinsic caspase cascade, NF-kB and p38 activation. p38 inhibitor SB203580 reverted the angiotensin II oxidant effects while the p38 constitutively activation, by MKK6 transfection, abrogated the zofenoprilat effects. Characterizing the zofenoprilat downstream effector we found that zofenoprilat reverted the SirT-1 downregulation induced by angiotensin II. p38 activation by angiotensin II was strictly correlated with SirT1 protein downregulation; SB203580 significantly prevented SirT1 downregulation induced by angiotensin II while the p38 constitutive activation abolished SIRT1 protein basal levels. p38 directly bound SirT1 sequestering it in the cytoplasm. SirT1 inhibition by sirtinol annulled zofenoprilat action while SirT1 overexpression reverted the cytotoxic effects of angiotensin II. Finally, zofenoprilat negatively controlled angiotensin I receptor protein expression through SirT1.
  
  
  CONCLUSIONS
  The p38-SirT1 axis is found markedly relevant in modulating the cardiovascular benefit deriving from ACE-inhibitors and might represent a novel target for innovative drugs in cardiovascular prevention.
authors.affiliation: aDepartment of Applied Clinical Sciences and Biotechnology, University of L'Aquila bDepartment MeSVA, University of L'Aquila, L'Aquila, Italy cDepartment of Molecular Immunology, Virology, and Medical Genetics, The Ohio State University, Columbus, Ohio, USA dPreclinical Development Department, Menarini Ricerche, Firenze, Italy *Francesco Marampon and Giovanni L. Gravina contributed equally to the writing of this article.
authors.forename: Francesco
authors.initials: F
authors.lastname: Marampon
authors.forename: Giovanni L
authors.initials: GL
authors.lastname: Gravina
authors.forename: Luca
authors.initials: L
authors.lastname: Scarsella
authors.forename: Claudio
authors.initials: C
authors.lastname: Festuccia
authors.forename: Francesca
authors.initials: F
authors.lastname: Lovat
authors.forename: Carmela
authors.initials: C
authors.lastname: Ciccarelli
authors.forename: Bianca M
authors.initials: BM
authors.lastname: Zani
authors.forename: Lorella
authors.initials: L
authors.lastname: Polidoro
authors.forename: Davide
authors.initials: D
authors.lastname: Grassi
authors.forename: Giovambattista
authors.initials: G
authors.lastname: Desideri
authors.forename: Stefano
authors.initials: S
authors.lastname: Evangelista
authors.forename: Claudio
authors.initials: C
authors.lastname: Ferri
mesh_terms: D000804:Angiotensin II / Q000378:metabolism*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D017209:Apoptosis; D002216:Captopril / Q000031:analogs & derivatives / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism; D002470:Cell Survival; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D005786:Gene Expression Regulation; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D048669:MAP Kinase Kinase 6 / Q000378:metabolism; D018384:Oxidative Stress; D011725:Pyridines / Q000494:pharmacology; D017382:Reactive Oxygen Species; D056564:Sirtuin 1 / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D007093:Imidazoles; D011725:Pyridines; D017382:Reactive Oxygen Species; D013481:Superoxides; D000804:Angiotensin II; C065520:zofenoprilate; D002216:Captopril; D048051:p38 Mitogen-Activated Protein Kinases; D048669:MAP Kinase Kinase 6; C482566:MAP2K6 protein, human; C447939:SIRT1 protein, human; D056564:Sirtuin 1; C093642:SB 203580