July 2018
Volume 59, Issue 9
Open Access
ARVO Annual Meeting Abstract  |   July 2018
Loss of PGC-1α function in RPE induces EMT and promotes retinal degeneration
Author Affiliations & Notes
  • Mariana Aparecida Rosales
    Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
    Schepens Eye Research Institute of Mass Eye and Ear, Boston, Massachusetts, United States
  • Magali Saint-Geniez
    Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
    Schepens Eye Research Institute of Mass Eye and Ear, Boston, Massachusetts, United States
  • Footnotes
    Commercial Relationships   Mariana Aparecida Rosales, None; Magali Saint-Geniez, None
  • Footnotes
    Support  The Grimshaw Foundation (MSG), Research to Prevent Blindness Unrestricted Grant (MSG), BrightFocus Foundation (MSG), NIH National Eye – Institute core grant P30EYE003790, fellowship from the CNPq 210474/2014-9 (MR)
Investigative Ophthalmology & Visual Science July 2018, Vol.59, 1185. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Mariana Aparecida Rosales, Magali Saint-Geniez; Loss of PGC-1α function in RPE induces EMT and promotes retinal degeneration. Invest. Ophthalmol. Vis. Sci. 2018;59(9):1185.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : Epithelial-to-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells is central to numerous degenerative ocular diseases including proliferative vitreoretinopathy and AMD. We have previously shown that PGC-1α, a core regulator of oxidative metabolism, is involved in RPE differentiation and that its silencing triggers rapid mitochondrial and autophagy dysfunctions. As metabolic defects are known to promote EMT, we examined the consequences of PGC-1α deletion on RPE transdifferentiation in vivo and in vitro.

Methods : PGC1α-deficient RPE cells were generated by stable expression of shPGC-1α in ARPE-19. shPGC-1α and shControl ARPE-19 cells were maturated and maintained in serum free condition for up to 21 days. Change in EMT-associated genes was analyzed by qPCR and immunohistochemistry. RPE-specific PGC-1s KO mice were generated by subretinal injection of AAV2/1-Cre in 8 weeks old C57Bl/6J;α,β double floxed mice (n=10; 6 females, 4 males). AAV2/1-GFP injected mice were used as controls (n= 9; 4 females, 5 males). Specificity and efficiency of Cre expression was confirmed by histology and qPCR. Two and four months after AAV-delivery, morphological and functional changes were evaluated by fundus, OCT, ERG and electron microscopy.

Results : EMT in PGC-1α silenced cells was first evidenced at day 7 by the reorganization of the fibrillar intermediate filaments into dense prenuclear coils. These morphological changes were associated with progressive loss of tight-junctions and cell-contact inhibition at day 14. Robust upregulation of the EMT-associated genes ZEB1 (p≤0.05), VIM (p≤0.01) and TWIST1 (p≤0.01) was detected at day 21. Similar RPE dedifferentiation was observed 2 and 4 months following RPE-specific deletion of the PGC-1 isoforms in adult mice. RPE anomalies were characterized by mitochondrial defects, pigmentary changes, cellular dissociation and migration. RPE dysfunction was associated with significant retinal degeneration demonstrated by reduced a- (p≤0.001), b- (p≤0.001), and c-waves (p≤0.01) amplitudes from ERG recordings and decreased total retinal thickness (p≤0.0001) measured by OCT.

Conclusions : These results demonstrate that sustained PGC-1α silencing in adult RPE cells induces EMT and subsequent retinal degeneration. Our findings support a role for PGC-1α and metabolic dysfunction in ocular pathologies associated with RPE EMT.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.

×
×

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.

×