Hyperoxia causes decreased expression of vascular endothelial growth factor and endothelial cell apoptosis in adult retina

Haruhiko Yamada, Eri Yamada, Sean F. Hackett, Hiroaki Ozaki, Naoyuki Okamoto, Peter A. Campochiaro

Research output: Contribution to journalArticle

Abstract

Mice or humans with photoreceptor degenerations experience permeability and dropout of retinal capillaries. Loss of photoreceptors results in decreased oxygen usage and thinning of the retina with increased oxygen delivery to the inner retina. To investigate the possibility that increased tissue oxygen plays a role in the vascular damage, we exposed adult mice to hyperoxia, which also increases oxygen in the retina. After 1, 2, or 3 weeks of hyperoxia, there was a statistically significant decrease in retinal vascular density that was not reversible, and endothelial cell apoptosis was demonstrated by TUNEL staining. Mice exposed to hyperoxia and mice with photoreceptor degeneration both showed decreased expression of VEGF in the retina. After complete or near-complete degeneration of photoreceptors, there was increased expression of VEGF in RPE cells, which may explain the association of photoreceptor degeneration and neovascularization in or around the RPE. Increased expression of VEGF in photoreceptors of transgenic mice failed to prevent hyperoxia-induced retinal capillary dropout. These data suggest that increased oxygen in the retina, either by increased inspired oxygen or by photoreceptor degeneration, results in endothelial cell death and dropout of capillaries. Decreased expression of VEGF may be a contributing factor, but the situation may be more complicated for mature retinal vessels than it is for immature vessels, because VEGF replacement does not rescue mature retinal vessels, suggesting that other factors may also be involved.

Original languageEnglish (US)
Pages (from-to)149-156
Number of pages8
JournalJournal of Cellular Physiology
Volume179
Issue number2
DOIs
StatePublished - Apr 19 1999

ASJC Scopus subject areas

  • Physiology
  • Clinical Biochemistry
  • Cell Biology

Fingerprint Dive into the research topics of 'Hyperoxia causes decreased expression of vascular endothelial growth factor and endothelial cell apoptosis in adult retina'. Together they form a unique fingerprint.

  • Cite this