title: Vasoinhibin gene transfer by adenoassociated virus type 2 protects against VEGF- and diabetes-induced retinal vasopermeability.
abstract: OBJECTIVE
  Specific proteolytic cleavages of the hormone prolactin (PRL) generate vasoinhibins, a family of peptides (including 16-kDa PRL) that are able to inhibit the pathologic increase in retinal vasopermeability (RVP) associated with diabetes. Here the authors tested the ability of an adenoassociated virus type 2 (AAV2) vasoinhibin vector to inhibit vascular endothelial growth factor (VEGF)- and diabetes-induced RVP.
  
  
  METHODS
  AAV2 vectors encoding vasoinhibin, PRL, or soluble VEGF receptor 1 (soluble FMS-like tyrosine kinase-1 [sFlt-1]) were injected intravitreally into the eyes of rats. Four weeks later, either VEGF was injected intravitreally or diabetes was induced with streptozotocin. Tracer accumulation was evaluated as an index of RVP using fluorescein angiography or the Evans blue dye method. RT-PCR verified transgene expression in the retina, and the intravitreal injection of an AAV2 vector encoding green fluorescent protein revealed transduced cells in the retinal ganglion cell layer. In addition, Western blot analysis of AAV2-transduced HEK293 cells confirmed the expression and secretion of the vector-encoded proteins.
  
  
  RESULTS
  The AAV2-vasoinhibin vector prevented the increase in tracer accumulation that occurs 24 hours after the intravitreal injection of VEGF. Diabetes induced a significant increase in tracer accumulation compared with nondiabetic controls. This increase was blocked by the AAV2-vasoinhibin vector and reduced by the AAV2-sFlt-1 vector. The AAV2-PRL vector had no effect.
  
  
  CONCLUSIONS
  These results show that an AAV2-vasoinhibin vector prevents pathologic RVP and suggest it could have therapeutic value in patients with diabetic retinopathy.
authors: Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Mexico.
authors: Mayda
authors: M
authors: Ramírez
authors: Zhijian
authors: Z
authors: Wu
authors: Bibiana
authors: B
authors: Moreno-Carranza
authors: Michael C
authors: MC
authors: Jeziorski
authors: Edith
authors: E
authors: Arnold
authors: Nundehui
authors: N
authors: Díaz-Lezama
authors: Gonzalo
authors: G
authors: Martínez de la Escalera
authors: Peter
authors: P
authors: Colosi
authors: Carmen
authors: C
authors: Clapp
mesh_terms: D000418:Albumins / Q000493:pharmacokinetics; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000235:genetics*; D004396:Coloring Agents / Q000493:pharmacokinetics; D000229:Dependovirus / Q000235:genetics*; D003911:Dextrans / Q000493:pharmacokinetics; D003921:Diabetes Mellitus, Experimental / Q000150:complications* / Q000235:genetics; D003930:Diabetic Retinopathy / Q000235:genetics / Q000628:therapy*; D004195:Disease Models, Animal; D005070:Evans Blue / Q000493:pharmacokinetics; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D049452:Green Fluorescent Proteins / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D058449:Intravitreal Injections; D008297:Male; D010957:Plasmids / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D012166:Retinal Hemorrhage / Q000139:chemically induced / Q000235:genetics / Q000628:therapy; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
chemical_list: D000418:Albumins; D018797:Cell Cycle Proteins; D004396:Coloring Agents; D003911:Dextrans; C493181:VASH1 protein, human; D042461:Vascular Endothelial Growth Factor A; C015219:fluorescein isothiocyanate dextran; C467498:vascular endothelial growth factor A, rat; D049452:Green Fluorescent Proteins; D005070:Evans Blue; D016650:Fluorescein-5-isothiocyanate