title: Compounds blocking methylglyoxal-induced protein modification and brain endothelial injury.
abstract: OBJECTIVE
  Elevated levels of reactive carbonyl species such as methylglyoxal triggers carbonyl stress and activates a series of inflammatory responses leading to accelerated vascular damage. Carbonyl stress is implicated in conditions and diseases like aging, diabetes mellitus, Alzheimer's disease and cardiovascular diseases. Our aim was to examine the effects of methylglyoxal on human hCMEC/D3 brain endothelial cells and search for protective molecules to prevent endothelial damage.
  
  
  METHODS
  Methylglyoxal-induced modification of albumin was tested in a cell-free assay. Endothelial cell viability was monitored by impedance measurement in real-time. The following compounds were tested in cell-free and viability assays: β-alanine, all-trans-retinoic acid, aminoguanidine, ascorbic acid, L-carnosine, GW-3333, indapamide, piracetam, γ-tocopherol, U0126, verapamil. Barrier function of brain endothelial monolayers was characterized by permeability measurements and visualized by immunohistochemistry for β-catenin. mRNA expression level of 60 selected blood-brain barrier-related genes in hCMEC/D3 cells was investigated by a custom Taqman gene array.
  
  
  RESULTS
  Methylglyoxal treatment significantly elevated protein modification, exerted toxicity, reduced barrier integrity, increased permeability for markers FITC-dextran and albumin and caused higher production of reactive oxygen species in hCMEC/D3 endothelial cells. Changes in the mRNA expression of 30 genes coding tight junction proteins, transporters and enzymes were observed in methylglyoxal-treated hCMEC/D3 cells. From the tested 11 compounds only all-trans-retinoic acid, an antioxidant and antiglycation agent, U0126, a MAP/ERK kinase inhibitor and aminoguanidine attenuated methylglyoxal-induced damage in hCMEC/D3 cells.
  
  
  CONCLUSIONS
  All-trans-retinoic acid and inhibition of the MAP/ERK signaling pathway may be protective in carbonyl stress induced brain endothelial damage.
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary; Department of Biotechnology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
authors.forename: Andrea E
authors.initials: AE
authors.lastname: Tóth
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary; Department of Biotechnology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Tóth
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Fruzsina R
authors.initials: FR
authors.lastname: Walter
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Lóránd
authors.initials: L
authors.lastname: Kiss
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Szilvia
authors.initials: S
authors.lastname: Veszelka
authors.affiliation: Avidin Ltd., Szeged, Hungary; Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Ózsvári
authors.affiliation: Avidin Ltd., Szeged, Hungary; Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
authors.forename: László G
authors.initials: LG
authors.lastname: Puskás
authors.affiliation: Department of Microbiology and Hygiene, Charité-University Medicine Berlin, Berlin, Germany.
authors.forename: Markus M
authors.initials: MM
authors.lastname: Heimesaat
authors.affiliation: Department of Pharmaceutical Care and Health Sciences, Fukuoka University, Fukuoka, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Dohgu
authors.affiliation: Department of Pharmaceutical Care and Health Sciences, Fukuoka University, Fukuoka, Japan.
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Kataoka
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary; Department of Biotechnology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
authors.forename: Gábor
authors.initials: G
authors.lastname: Rákhely
authors.affiliation: Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary. Electronic address: deli.maria@brc.mta.hu.
authors.forename: Mária A
authors.initials: MA
authors.lastname: Deli
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism; D000975:Antioxidants / Q000494:pharmacology; D001812:Blood-Brain Barrier / Q000166:cytology / Q000187:drug effects / Q000473:pathology*; D002070:Butadienes / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D042783:Endothelial Cells / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors; D006146:Guanidines / Q000494:pharmacology; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects; D009570:Nitriles / Q000494:pharmacology; D011765:Pyruvaldehyde / Q000037:antagonists & inhibitors* / Q000378:metabolism* / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D062725:Tight Junction Proteins / Q000235:genetics; D014212:Tretinoin / Q000494:pharmacology*; D051176:beta Catenin / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002070:Butadienes; D004791:Enzyme Inhibitors; D006146:Guanidines; D009570:Nitriles; D017382:Reactive Oxygen Species; D062725:Tight Junction Proteins; C113580:U 0126; D051176:beta Catenin; D014212:Tretinoin; D011765:Pyruvaldehyde; D048049:Extracellular Signal-Regulated MAP Kinases; C004479:pimagedine
keywords: All-trans-retinoic acid; Aminoguanidine; Human brain endothelial cell; Methylglyoxal; Protein modification; U0126