September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
Vascular Dysfunction in Per2m/m mice is Mediated via the Upregulation Of Connective Tissue Growth Factor
Author Affiliations & Notes
  • Maria B Grant
    Ophthalmology , Indiana University , Indianapolis, Indiana, United States
  • Vaishnavi Jadhav
    Ophthalmology , Indiana University , Indianapolis, Indiana, United States
  • Jude Al-Sabah
    Ophthalmology , Indiana University , Indianapolis, Indiana, United States
  • Brahim Chaqour
    Cell Biology, SUNY, Brooklyn, New York, United States
  • Ashay D Bhatwadekar
    Ophthalmology , Indiana University , Indianapolis, Indiana, United States
  • Footnotes
    Commercial Relationships   Maria Grant, None; Vaishnavi Jadhav, None; Jude Al-Sabah, None; Brahim Chaqour, None; Ashay Bhatwadekar, None
  • Footnotes
    Support  NIH grants: R01EY0126001, R01EY007739, R01HL110170, R01DK090730. Research to Prevent Blindness Unrestricted grant awarded to the Department of Ophthalmology at IUPUI.
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 2716. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Maria B Grant, Vaishnavi Jadhav, Jude Al-Sabah, Brahim Chaqour, Ashay D Bhatwadekar; Vascular Dysfunction in Per2m/m mice is Mediated via the Upregulation Of Connective Tissue Growth Factor. Invest. Ophthalmol. Vis. Sci. 2016;57(12):2716.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : We previously reported that Per2m/m mice that are lacking circadian rhythms recapitulate the retinal vascular alterations associated with diabetic retinopathy (DR). The vascular dysfunction in Per2m/m mice was largely attributed to dysregulated expression of connective tissue growth factor (CTGF/CCN2), a downstream target and core component of the TGF-β pathway. At the molecular levels, CTGF gene expression is dependent on the canonical Wnt/β-catenin pathway. Interestingly, signaling through PER2 leads to increased casein kinase 1 (CK1)-ε activity, a signaling events also associated with β-catenin phosphorylation and degradation. Therefore, we hypothesized that silencing of Per2 increases β-catenin stability and nuclear translocation and subsequent transactivation of the CTGF gene.

Methods : Eyes from wild type and Per2m/m were enucleated, sectioned and stained for CTGF. Human retinal endothelial cells (HRECs) were transfected with siRNA for Per2 and the protein expression of CTGF and β-catenin was determined using qRT-PCR and western blot analysis. The nuclear localization of β-catenin was examined by immuonofluorescence. ATCF/LEF luciferase reporter assay (TOPFLASH) assay was used to validate the involvement of β-catenin in the activation of CTGF.

Results : Per2m/m retinas showed increased CTGF immunostaining in the ganglion cell layer and retinal endothelium. Loss of Per2 function resulted in increased expression of CTGF and β-catenin. siRNA-mediated silencing of Per2 in HRECs increased nuclear accumulation of β-catenin as compared to the control siRNA. The TOPFALSH assay showed an increase in luminescence for HRECs transfected with Per2 siRNA.

Conclusions : Our studies show that loss of Per2 results in activation of CTGF via nuclear entry of β-catenin. The future therapies aimed at targeting the β-catenin-CTGF pathway may provide a novel tool for correction of vascular dysfunction in DR.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

×
×

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.

×