title: In vitro effects of bevacizumab treatment on newborn rat retinal cell proliferation, death, and differentiation.
abstract: OBJECTIVE
  Vascular endothelial growth factor (VEGF) is an important signal protein in vertebrate nervous development, promoting neurogenesis, neuronal patterning, and glial cell growth. Bevacizumab, an anti-VEGF agent, has been extensively used for controlling pathological retinal neovascularization in adult and newborn patients, although its effect on the developing retina remains largely unknown. The purpose of this study was to investigate the effect of bevacizumab on cell death, proliferation, and differentiation in newborn rat retina.
  
  
  METHODS
  Retinal explants of sixty 2-day-old Lister hooded rats were obtained after eye enucleation and maintained in culture media with or without bevacizumab for 2 days. Immunohistochemical staining was assessed against proliferating cell nuclear antigen (PCNA, to detect cell proliferation); caspase-3 and beclin-1 (to investigate cell death); and vimentin and glial fibrillary acidic protein (GFAP, markers of glial cells). Gene expressions were quantified by real-time reverse-transcription polymerase chain reaction. Results from treatment and control groups were compared.
  
  
  RESULTS
  No significant difference in the staining intensity (on immunohistochemistry) of PCNA, caspase-3, beclin-1, and GFAP, or in the levels of PCNA, caspase-3, beclin-1, and vimentin mRNA was observed between the groups. However, a significant increase in vimentin levels and a significant decrease in GFAP mRNA expression were observed in bevacizumab-treated retinal explants compared with controls.
  
  
  CONCLUSIONS
  Bevacizumab did not affect cell death or proliferation in early developing rat retina but appeared to interfere with glial cell maturation by increasing vimentin levels and downregulating GFAP gene expression. Thus, we suggest anti-VEGF agents be used with caution in developing retinal tissue.
authors.affiliation: Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Nádia C O
authors.initials: NC
authors.lastname: Miguel
authors.forename: Monique
authors.initials: M
authors.lastname: Matsuda
authors.forename: André Luís F
authors.initials: AL
authors.lastname: Portes
authors.forename: Silvana
authors.initials: S
authors.lastname: Allodi
authors.forename: Rosália
authors.initials: R
authors.lastname: Mendez-Otero
authors.forename: Thiago
authors.initials: T
authors.lastname: Puntar
authors.forename: Alfred
authors.initials: A
authors.lastname: Sholl-Franco
authors.forename: Paloma G
authors.initials: PG
authors.lastname: Krempel
authors.forename: Mário L R
authors.initials: ML
authors.lastname: Monteiro
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D061067:Antibodies, Monoclonal, Humanized / Q000494:pharmacology*; D000068258:Bevacizumab; D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004195:Disease Models, Animal; D019084:Fluorescent Antibody Technique, Indirect; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D012160:Retina / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D020533:Angiogenesis Inhibitors; D061067:Antibodies, Monoclonal, Humanized; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab