June 2015
Volume 56, Issue 7
Free
ARVO Annual Meeting Abstract  |   June 2015
Cathepsin D may play a role in inflammation induced alteration of Blood-Retinal Barrier in Diabetic Retinopathy
Author Affiliations & Notes
  • Finny Monickaraj
    Surgery/Opthalmology, University of New Mexico, Albuquerque, NM
  • Paul McGuire
    Surgery/Opthalmology, University of New Mexico, Albuquerque, NM
    Cell Biology and Physiology, University of New Mexico, Albuquerque, NM
  • Carolina Franco Nitta
    Surgery/Opthalmology, University of New Mexico, Albuquerque, NM
    NMVA Health Care System, Albuquerque, NM
  • Amy Lucero
    Cell Biology and Physiology, University of New Mexico, Albuquerque, NM
  • Arup Das
    Surgery/Opthalmology, University of New Mexico, Albuquerque, NM
    NMVA Health Care System, Albuquerque, NM
  • Footnotes
    Commercial Relationships Finny Monickaraj, None; Paul McGuire, None; Carolina Franco Nitta, None; Amy Lucero, None; Arup Das, None
  • Footnotes
    Support None
Investigative Ophthalmology & Visual Science June 2015, Vol.56, 4273. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Finny Monickaraj, Paul McGuire, Carolina Franco Nitta, Amy Lucero, Arup Das; Cathepsin D may play a role in inflammation induced alteration of Blood-Retinal Barrier in Diabetic Retinopathy. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):4273.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: We have shown that monocytes/macrophages recruited into the retina in response to diabetes facilitate the breakdown of the blood-retinal barrier (BRB). We have identified a 30-100kDa fraction of macrophage-conditioned medium responsible for alteration of retinal permeability. In this study we further characterized this fraction and identified Cathepsin D and its role in endothelial barrier alteration and diabetic retinopathy.

Methods: Phorbol 12-myristate 13-Acetate (PMA) stimulated U937 human macrophage conditioned media was fractioned by molecular weight and the effective fraction (30-100kDa) was further analysed by Liquid Chromatography-Mass Spectrometry (LC-MS). A role for cathepsin D in mediating transendothelial resistance in human retinal endothelial cells (HREC) was measured by electric cell-substrate Impedence Sensing (ECIS). Cathepsin D was immunoprecipitated with agarose beads from the 30-100kDa fraction and used to treat the HREC. The specificity of its role was confirmed by siRNA studies. Cathepsin D levels in retinas of four month streptozotocin induced diabetic mice was measured by western blot.

Results: Mass spectroscopy results identified 30 proteins differentially regulated in macrophage conditioned 30-100kDa fraction in comparison with non stimulated cells, which included heat shock proteins, PAI-2, SOD and Cathepsin D. Cathepsin D was selected for further studies due to its known role in barrier alteration in cardiovascular disease and cancer. HREC treated with immunoprecipitated cathepsin D beads showed a significant alteration in barrier resistance. Treatement of U937 cells with cathepsin D siRNA blocked this effect. Additionally retinas from four month diabetic mice exhibited significantly increased levels of cathepsin D protein.

Conclusions: ​In this study we have shown the role of cathepsin D as a potential therapeutic target in diabetic retinopathy due to its role in altering the BRB and its increased levels in diabetic animals.

×
×

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.

×