title: Inhibition of GSK3α/β promotes increased pulmonary endothelial permeability to albumin by reactive oxygen/nitrogen species.
abstract: Glycogen synthase kinase 3α/β (GSK3α/β) is a serine/threonine kinase that participates in numerous processes in many cell types. Importantly, the role of GSK3α/β in homeostatic maintenance of the pulmonary endothelial cell barrier to protein is not known. We tested the hypothesis that GSK3α/β regulates endothelial barrier function by measuring the permeability to albumin of a rat pulmonary microvessel endothelial cell monolayer (PMECM) treated with and without the selective GSK3α/β inhibitor SB 216763 (1.0, 5.0 and 10 uM) for 1 h. The treatment with the inhibitor SB 216763 caused a dose dependent decrease in phospho-β-catenin-Ser(33/37) levels indicating effective suppression of GSK3α/β. SB216763 caused an increase in both permeability to albumin and DCFDA (6-Carboxy-2',7'-Dichlorodihydrofluorescein Diacetate, Di(Acetoxymethyl Ester)) oxidation that were prevented by co-treatment with the anti-oxidant tiron or the nitric oxide synthase inhibitor L-NAME (Nω-nitro-l-arginine-methyl ester). In separate studies PMECMs were treated with the Akt inhibitor triciribine (12.5 uM) for 1 h to unmask Akt dependent constitutive suppression of GSK3α/β. Triciribine decreased phospho-GSK3α/β-Ser(21)/9 (i.e., the product of Akt) which was associated with an increase in phospho-β-catenin-Ser(33/37) (i.e., the product of GSK3α/β) indicating constitutive activity of Akt for GSK3α/β-Ser(21/9). The data indicates GSK3α/β inhibition causes increased endothelial monolayer protein permeability which is mediated by reactive oxygen/nitrogen species.
authors.affiliation: Department of Pharmaceutical Science, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Neumann
authors.forename: Hiba
authors.initials: H
authors.lastname: Alsaffar
authors.forename: Nancy
authors.initials: N
authors.lastname: Gertzberg
authors.forename: Arnold
authors.initials: A
authors.lastname: Johnson
mesh_terms: D000418:Albumins / Q000378:metabolism; D000818:Animals; D002199:Capillary Permeability / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D038362:Glycogen Synthase Kinase 3 / Q000037:antagonists & inhibitors*; D000071679:Glycogen Synthase Kinase 3 beta; D007211:Indoles / Q000008:administration & dosage / Q000494:pharmacology; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008301:Maleimides / Q000008:administration & dosage / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000418:Albumins; D004791:Enzyme Inhibitors; D007211:Indoles; D008301:Maleimides; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; C417521:SB 216763; D000071679:Glycogen Synthase Kinase 3 beta; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3; C448021:glycogen synthase kinase 3 alpha
keywords: Endothelial permeability; Inflammation; Lung injury; β-catenin