title: NADPH oxidase-generated reactive oxygen species are required for stromal cell-derived factor-1α-stimulated angiogenesis.
abstract: OBJECTIVE
  Reactive oxygen species (ROS) act as signaling molecules during angiogenesis; however, the mechanisms used for such signaling events remain unclear. Stromal cell-derived factor-1α (SDF-1α) is one of the most potent angiogenic chemokines. Here, we examined the role of ROS in the regulation of SDF-1α-dependent angiogenesis.
  
  
  RESULTS
  Bovine aortic endothelial cells were treated with SDF-1α, and intracellular ROS generation was monitored. SDF-1α treatment induced bovine aortic endothelial cell migration and ROS generation, with the majority of ROS generated by bovine aortic endothelial cells at the leading edge of the migratory cells. Antioxidants and nicotinamide adenine dinucleotide phosphate oxidase (NOX) inhibitors blocked SDF-1α-induced endothelial migration. Furthermore, knockdown of either NOX5 or p22phox (a requisite subunit for NOX1/2/4 activation) significantly impaired endothelial motility and tube formation, suggesting that multiple NOXs regulate SDF-1α-dependent angiogenesis. Our previous study demonstrated that c-Jun N-terminal kinase 3 activity is essential for SDF-1α-dependent angiogenesis. Here, we identified that NOX5 is the dominant NOX required for SDF-1α-induced c-Jun N-terminal kinase 3 activation and that NOX5 and MAP kinase phosphatase 7 (MKP7; the c-Jun N-terminal kinase 3 phosphatase) associate with one another but decrease this interaction on SDF-1α treatment. Furthermore, MKP7 activity was inhibited by SDF-1α, and this inhibition was relieved by NOX5 knockdown, indicating that NOX5 promotes c-Jun N-terminal kinase 3 activation by blocking MKP7 activity.
  
  
  CONCLUSIONS
  We conclude that NOX is required for SDF-1α signaling and that intracellular redox balance is critical for SDF-1α-induced endothelial migration and angiogenesis.
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill. pxinchun@med.unc.edu.
authors.forename: Xinchun
authors.initials: X
authors.lastname: Pi
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Liang
authors.initials: L
authors.lastname: Xie
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Portbury
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Sarayu
authors.initials: S
authors.lastname: Kumar
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Pamela
authors.initials: P
authors.lastname: Lockyer
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Xi
authors.initials: X
authors.lastname: Li
authors.affiliation: From the UNC McAllister Heart Institute (X.P., L.X., A.L.P., P.L., X.L., C.P.), Department of Medicine (X.P., L.X., A.L.P., P.L., X.L., C.P.), and Department of Chemistry (S.K.), University of North Carolina, Chapel Hill.
authors.forename: Cam
authors.initials: C
authors.lastname: Patterson
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001011:Aorta; D001393:Azoles / Q000494:pharmacology; D002417:Cattle; D002465:Cell Movement / Q000187:drug effects; D054377:Chemokine CXCL12 / Q000494:pharmacology / Q000502:physiology*; D054637:Dual-Specificity Phosphatases / Q000502:physiology; D042783:Endothelial Cells / Q000187:drug effects; D004730:Endothelium, Vascular / Q000166:cytology; D055785:Gene Knockdown Techniques; D006943:Hyperglycemia / Q000378:metabolism; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D054833:Isoindoles; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D048057:Mitogen-Activated Protein Kinase 10 / Q000502:physiology; D054639:Mitogen-Activated Protein Kinase Phosphatases / Q000502:physiology; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D016566:Organoselenium Compounds / Q000494:pharmacology; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
chemical_list: D000975:Antioxidants; D001393:Azoles; D054377:Chemokine CXCL12; D007527:Isoenzymes; D054833:Isoindoles; D008565:Membrane Proteins; D016566:Organoselenium Compounds; D017382:Reactive Oxygen Species; C042986:ebselen; D019255:NADPH Oxidases; D048057:Mitogen-Activated Protein Kinase 10; D054639:Mitogen-Activated Protein Kinase Phosphatases; D054637:Dual-Specificity Phosphatases; D000111:Acetylcysteine
keywords: NADPH oxidase; angiogenesis; migration; reactive oxygen species; stromal cell-derived factor-1α