title: Nitric oxide participates in IFN-gamma-induced HUVECs hyperpermeability.
abstract: The endothelial barrier function is tightly controlled by a broad range of signaling cascades including nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway. It has been proposed that disturbances in NO and cGMP production could interfere with proper endothelial barrier function. In this study, we assessed the effect of interferon-gamma (IFN-gamma), a pro-inflammatory cytokine, on NO and cGMP levels and examined the mechanisms by which NO and cGMP regulate the IFN-gamma-mediated HUVECs hyperpermeability. The flux of fluorescein isothiocyanate-labeled dextran across cell monolayers was used to study the permeability of endothelial cells. Here, we found that IFN-gamma significantly attenuated basal NO concentration and the increased NO levels supplied by a NO donor, sodium nitroprusside (SNP). Besides, application of IFN-gamma also significantly attenuated both the basal cGMP concentration and the increased cGMP production donated by a cell permeable cGMP analogue, 8-bromo-cyclic GMP (8-Br-cGMP). In addition, exposure of the cell monolayer to IFN-gamma significantly increased HUVECs basal permeability. However, L-NAME pretreatment did not suppress IFN-gamma-induced HUVECs hyperpermeability. L-NAME pretreatment followed by SNP or SNP pretreatment partially reduced IFN-gamma-induced HUVECs hyperpermeability. Pretreatment with a guanylate cyclase inhibitor, 6-anilino-5,8-quinolinedione (LY83583), led to a further increase in IFN-gamma-induced HUVECs hyperpermeability. The findings suggest that the mechanism underlying IFN-gamma-induced increased HUVECs permeability is partly related to the inhibition of NO production.
authors.affiliation: Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. zuraini@upm.edu.my.
authors.forename: C T
authors.initials: CT
authors.lastname: Ng
authors.forename: L Y
authors.initials: LY
authors.lastname: Fong
authors.forename: Y Y
authors.initials: YY
authors.lastname: Low
authors.forename: J
authors.initials: J
authors.lastname: Ban
authors.forename: M N
authors.initials: MN
authors.lastname: Hakim
authors.forename: Z
authors.initials: Z
authors.lastname: Ahmad
mesh_terms: D002199:Capillary Permeability / Q000187:drug effects*; D002463:Cell Membrane Permeability; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006162:Guanylate Cyclase / Q000037:antagonists & inhibitors; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D020030:Nitric Oxide Donors; D009599:Nitroprusside; C016276:8-bromocyclic GMP; D009569:Nitric Oxide; D007371:Interferon-gamma; D006162:Guanylate Cyclase; D006152:Cyclic GMP; D019331:NG-Nitroarginine Methyl Ester