title: The C-terminal module IV of connective tissue growth factor, through EGFR/Nox1 signaling, activates the NF-κB pathway and proinflammatory factors in vascular smooth muscle cells.
abstract: OBJECTIVE
  Connective tissue growth factor (CTGF/CCN2) is a developmental gene upregulated in pathological conditions, including cardiovascular diseases, whose product is a matricellular protein that can be degraded to biologically active fragments. Among them, the C-terminal module IV [CCN2(IV)] regulates many cellular functions, but there are no data about redox process. Therefore, we investigated whether CCN2(IV) through redox signaling regulates vascular responses.
  
  
  RESULTS
  CCN2(IV) increased superoxide anion (O2(•-)) production in murine aorta (ex vivo and in vivo) and in cultured vascular smooth muscle cells (VSMCs). In isolated murine aorta, CCN2(IV), via O2(•-), increased phenylephrine-induced vascular contraction. CCN2(IV) in vivo regulated several redox-related processes in mice aorta, including increased nonphagocytic NAD(P)H oxidases (Nox)1 activity, protein nitrosylation, endothelial dysfunction, and activation of the nuclear factor-κB (NF-κB) pathway and its related proinflammatory factors. The role of Nox1 in CCN2(IV)-mediated vascular responses in vivo was investigated by gene silencing. The administration of a Nox1 morpholino diminished aortic O2(•-) production, endothelial dysfunction, NF-κB activation, and overexpression of proinflammatory genes in CCN2(IV)-injected mice. The link CCN2(IV)/Nox1/NF-κB/inflammation was confirmed in cultured VSMCs. Epidermal growth factor receptor (EGFR) is a known CCN2 receptor. In VSMCs, CCN2(IV) activates EGFR signaling. Moreover, EGFR kinase inhibition blocked vascular responses in CCN2(IV)-injected mice.
  
  
  CONCLUSIONS
  CCN2(IV) is a novel prooxidant factor that in VSMCs induces O2(•-) production via EGFR/Nox1 activation. Our in vivo data demonstrate that CCN2(IV) through EGFR/Nox1 signaling pathway induces endothelial dysfunction and activation of the NF-κB inflammatory pathway. Therefore, CCN2(IV) could be considered a potential therapeutic target for redox-related cardiovascular diseases.
authors: 1 Cellular Biology in Renal Diseases Laboratory, Instituto de Investigación Sanitaria Fundación Jiménez Díaz, Universidad Autónoma Madrid , Madrid, Spain .
authors: Raúl R
authors: RR
authors: Rodrigues-Diez
authors: Ana Belen
authors: AB
authors: Garcia-Redondo
authors: Macarena
authors: M
authors: Orejudo
authors: Raquel
authors: R
authors: Rodrigues-Diez
authors: Ana Maria
authors: AM
authors: Briones
authors: Enrique
authors: E
authors: Bosch-Panadero
authors: Gyorgy
authors: G
authors: Kery
authors: Janos
authors: J
authors: Pato
authors: Alberto
authors: A
authors: Ortiz
authors: Mercedes
authors: M
authors: Salaices
authors: Jesus
authors: J
authors: Egido
authors: Marta
authors: M
authors: Ruiz-Ortega
mesh_terms: D000818:Animals; D055513:Connective Tissue Growth Factor / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D018613:Microscopy, Confocal; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D000074624:NADPH Oxidase 1; D016328:NF-kappa B / Q000378:metabolism*
chemical_list: C526318:CCN2 protein, mouse; D016328:NF-kappa B; D055513:Connective Tissue Growth Factor; D009247:NADH, NADPH Oxidoreductases; D000074624:NADPH Oxidase 1; C000614711:NOX1 protein, mouse; D066246:ErbB Receptors