September 2016
Volume 57, Issue 12
Open Access
ARVO Annual Meeting Abstract  |   September 2016
Regulation of retinal blood barrier by TNF alpha convertase, ADAM17, and its implication in diabetic macular edema
Author Affiliations & Notes
  • Diana Gutsaeva
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Khaled Hussein
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Folami Lamoke
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Hang Fai Kwok
    University of Macau, Macau, Macao
  • Ariel Solomon
    Allosterix-Pharma, Moshav-Shilat, Israel
  • Pamela M Martin
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Mohamed Al-Sayed Al-Shabrawey
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Manuela Bartoli
    Georgia Regents University, AUGUSTA, Georgia, United States
  • Footnotes
    Commercial Relationships   Diana Gutsaeva, None; Khaled Hussein, None; Folami Lamoke, None; Hang Fai Kwok, None; Ariel Solomon, Allosterix-Pharma (E); Pamela Martin, None; Mohamed Al-Shabrawey, None; Manuela Bartoli, None
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science September 2016, Vol.57, 3226. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Diana Gutsaeva, Khaled Hussein, Folami Lamoke, Hang Fai Kwok, Ariel Solomon, Pamela M Martin, Mohamed Al-Sayed Al-Shabrawey, Manuela Bartoli; Regulation of retinal blood barrier by TNF alpha convertase, ADAM17, and its implication in diabetic macular edema. Invest. Ophthalmol. Vis. Sci. 2016;57(12):3226.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : Tumor necrosis factor alpha convertase (TACE/ADAM17) is an important regulator of inflammatory and neuroprotective responses due to its sheddase activity towards cytokines, cytokine receptors and adhesion molecules. We have previously demonstrated that TACE/ADAM17 expression and activity are up-regulated in the diabetic rat and human retina. Here we aimed to further investigate TACE/ADAM17 implication and mode of action on paracellular permeability, a critical target of hyperglycemia and a pathogenic feature of diabetic retinopathy (DR).

Methods : Paracellular permeability in human and bovine retinal endothelial cells (HuREC and BREC, respectively) in cultures was assessed by the electrical cell-substrate impedance sensing (ECIS) technique in response to TNF alpha (20-100 ng/ml for 24 hours) and high glucose (HG; 25mM for 48 hours, conditioned medium). Western blotting and immunohistochemistry analyses were performed to assess expression levels and immunolocalization of the tight junction protein junction adhesion molecule A (JAM-A), a direct substrate of TACE/ADAM17. Inhibition of TACE/ADAM17 was achieved using a chemical inhibitor AL-4-1A1 (1 µM) or a human anti-ADAM17 inhibitory antibody D1(A12) (0.5 µM).

Results : HG and TNF alpha, given alone or in combination, promoted a significant decrease in paracellular permeability, as determined by the reduction of trans-endothelial electrical resistance in HuREC and BREC monolayers. Treatment of the cells with AL-4-1A1 inhibitor or anti-ADAM17 antibodies halted these effects and significantly restored barrier function. In addition, we have found that JAM-A-specific epifluorescence was decreased in cells stimulated with TNF alpha or HG, given alone or in combination. However, blockade of AL-4-1A1 activity using AL-4-1A1 inhibitor AL-4-1A1 or anti-ADAM17 antibodies restored normal JAM-A-specific epifluorescence.

Conclusions : The sum of the obtained results directly implicates TACE/ADAM17 in TNF alpha and HG-induced paracellular permeability through a mechanism involving shedding of JAM-A from the cells surface and, potentially, redistribution of intercellular junctional proteins. These data further support a role for TACE/ADAM17 in DR pathogenesis and suggest the use of specific inhibitors of this convertase as potential treatment for diabetic macular edema and 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.

×