title: Insulin-like growth factor-1 protects from vascular stenosis and accelerates re-endothelialization in a rat model of carotid artery injury.
abstract: BACKGROUND
  IGF-1 is a potent mitogen for vascular smooth muscle cells, but exerts protective effects on endothelial cells that may trigger antiatherogenic mechanisms.
  
  
  OBJECTIVE
  This study was designed to test the hypothesis that an IGF-1 excess following arterial injury prevents neointima formation and vascular stenosis.
  
  
  METHODS
  Rats were subjected to carotid balloon injury and treated with IGF-1 (1.2 mg kg(-1) per die) or saline for 10 days.
  
  
  RESULTS
  In IGF-1 treated animals, high tissue levels of eNOS, Akt and its phosphorylated form were found, confirming activation of IGF-1-dependent signaling pathways. IGF-1 markedly reduced neointima formation and post-injury arterial stenosis. IGF-1 exerted proliferative and anti-apoptotic effects in the media of injured carotids, but inhibited mitotic activity and induced apoptosis in the neointima. Furthermore, IGF-1 stimulated mobilization of progenitor endothelial cells and re-endothelialization of the injured arteries. L-NAME administration inhibited IGF-1 vasculoprotective effects.
  
  
  CONCLUSIONS
  IGF-1 attenuates post-injury carotid stenosis by exerting differential effects in the neointima and tunica media with regard to the key components of the response to injury. The data point to a novel role of IGF-1 as a potent vasculoprotective factor.
authors.affiliation: Department of Internal Medicine, University Federico II, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Cittadini
authors.forename: M G
authors.initials: MG
authors.lastname: Monti
authors.forename: M C
authors.initials: MC
authors.lastname: Castiello
authors.forename: E
authors.initials: E
authors.lastname: D'Arco
authors.forename: G
authors.initials: G
authors.lastname: Galasso
authors.forename: D
authors.initials: D
authors.lastname: Sorriento
authors.forename: L
authors.initials: L
authors.lastname: Saldamarco
authors.forename: A
authors.initials: A
authors.lastname: De Paulis
authors.forename: R
authors.initials: R
authors.lastname: Napoli
authors.forename: G
authors.initials: G
authors.lastname: Iaccarino
authors.forename: L
authors.initials: L
authors.lastname: Saccà
mesh_terms: D000818:Animals; D020212:Carotid Artery Injuries; D016893:Carotid Stenosis; D002404:Catheterization / Q000009:adverse effects; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000502:physiology*; D007334:Insulin-Like Growth Factor I; D020011:Protective Agents; D051381:Rats; D012038:Regeneration; D017539:Tunica Intima; D017540:Tunica Media
chemical_list: D020011:Protective Agents; D007334:Insulin-Like Growth Factor I