May 2005
Volume 46, Issue 13
ARVO Annual Meeting Abstract  |   May 2005
Differential Gene Expression of CCN–Family Members in Retinas of VEGF–Injected Rat Eyes
Author Affiliations & Notes
  • I. Klaassen
    Ophthalmology, IOI/AMC, Amsterdam, The Netherlands
  • E.J. Kuiper
    Ophthalmology, IOI/AMC, Amsterdam, The Netherlands
  • J.M. Hughes
    Ophthalmology, IOI/AMC, Amsterdam, The Netherlands
  • R.O. Schlingemann
    Ophthalmology, IOI/AMC, Amsterdam, The Netherlands
  • Footnotes
    Commercial Relationships  I. Klaassen, None; E.J. Kuiper, None; J.M. Hughes, None; R.O. Schlingemann, None.
  • Footnotes
    Support  Dutch Diabetes Fund DFN1999.050
Investigative Ophthalmology & Visual Science May 2005, Vol.46, 1366. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      I. Klaassen, E.J. Kuiper, J.M. Hughes, R.O. Schlingemann; Differential Gene Expression of CCN–Family Members in Retinas of VEGF–Injected Rat Eyes . Invest. Ophthalmol. Vis. Sci. 2005;46(13):1366.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Abstract: : Purpose: Proliferative diabetic retinopathy (PDR) and exudative age related macular degeneration (AMD) are the leading causes of blindness in Western countries. Progression of both diseases is characterized by neovascularization and fibrosis, which eventually leads to irreversible loss of vision. The major factor responsible for neovascularization was identified as vascular endothelial growth factor–A (VEGF). VEGF is suggested to act in concert with many other cytokines. A recently discovered growth factor, which also plays a role in extracellular matrix production and fibrosis, is connective tissue growth factor (CTGF, CCN2). In vitro studies have shown that VEGF can induce CCN2 transcription in retinal endothelial cells and pericytes, indicating a possible role of CCN2 in ocular neovascularization and fibrosis. In order to study possible VEGF–induced expression of CCN2 in vivo, we investigated mRNA expression patterns of CCN2 in the retina of VEGF–injected rat eyes. In addition, we investigated mRNA expression of other CCN–family members and extracellular matrix components. Methods: Recombinant rat VEGF164 (rrVegf164, 300ng) or PBS was injected intra–vitreally in male Wistar rats. Gene expression in whole retinas was investigated after 24 and 48 hours by real–time quantitative RT–PCR. A normalization factor based on the expression levels of three housekeeping genes was calculated by using the geometric mean of the absolute values. Results: We demonstrated a significant induction of CCN2 and CCN1 (CYR61) 24 hours after VEGF injection. 48 hours after injection, CCN2 transcription levels were on average higher, although no longer significantly, than in control retinas and CCN1 expression was back to normal. As for the remaining CCN–family members expression levels were unchanged for CCN4, while CCN3, –5 and –6 expression levels were undetectable. Fibronectin and transforming growth factor–ß2 (TGF–ß2) expression was elevated significantly 24 hours after injection and decreased 48 hours after injection to levels that were not significantly different from controls. This was in contrast to expression levels of collagen type IV (Col3a4), TGF–ß1 and tissue inhibitor of metalloproteinase 2 (TIMP–2), which remained comparable to control levels at both time points. Conclusions: VEGF–injection in rat eyes induces upregulation of retinal CCN1, CCN2 and TGF–ß2 genes and selected extracellular matrix genes. In vivo regulation of these genes by VEGF may underlie crucial mechanisms involved in fibrosis and neovascularization in the progression of DR and AMD.

Keywords: diabetic retinopathy • gene/expression • extracellular matrix 

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.