Progenitor cell-derived factors enhance photoreceptor survival in rat retinal explants

Brain Res. 2008 Aug 28:1227:226-33. doi: 10.1016/j.brainres.2008.06.077. Epub 2008 Jun 28.

Abstract

Explantation of postnatal rat retinas is associated with degenerative events that show morphological similarities to human retinal degenerative disorders. The most evident morphological features are photoreceptor apoptosis involving caspase-3 and Müller cell activation. The purpose of the present study was to determine the content of protective factors in rat retinal progenitor cells and analyze the influence of the identified factors on the survival of photoreceptor cells and retinal gliosis. Tissue inhibitors of matrix metalloproteinase-1 (TIMP-1) and vascular endothelial growth factor (VEGF) were identified as putative beneficial factors, and their combined effect was examined in rat retinal explant cultures. Photoreceptor apoptosis was estimated by cell counts of cleaved caspase-3 and caspase-12 immunolabeled as well as TUNEL labeled cells. TIMP-1 and VEGF in combination significantly suppressed photoreceptor apoptosis involving caspase-3 activation. Cell counts of caspase-12 and TUNEL labeled photoreceptors showed no significant difference between the experiment and control retinas. TIMP-1 and VEGF appeared to have no effect on Müller cell activation as measured by GFAP and Ki-67 immunohistochemistry. Our data suggest that TIMP-1 and VEGF in combination promote the survival of photoreceptor cells in rat retinal explants, possibly by affecting a caspase-3 signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Caspase 12 / metabolism
  • Caspase 3 / metabolism
  • Cell Survival / drug effects
  • Cells, Cultured
  • Female
  • Glial Fibrillary Acidic Protein / metabolism
  • Immunohistochemistry
  • In Situ Nick-End Labeling
  • Ki-67 Antigen / metabolism
  • Neuroglia / cytology
  • Neuroglia / metabolism
  • Photoreceptor Cells / cytology
  • Photoreceptor Cells / drug effects*
  • Photoreceptor Cells / metabolism
  • Pregnancy
  • Rats
  • Rats, Sprague-Dawley
  • Retina / cytology
  • Retina / drug effects
  • Retina / metabolism
  • Stem Cells / cytology
  • Stem Cells / metabolism*
  • Tissue Culture Techniques
  • Tissue Inhibitor of Metalloproteinase-1 / pharmacology*
  • Vascular Endothelial Growth Factor A / pharmacology*

Substances

  • Glial Fibrillary Acidic Protein
  • Ki-67 Antigen
  • Tissue Inhibitor of Metalloproteinase-1
  • Vascular Endothelial Growth Factor A
  • Caspase 12
  • Caspase 3