April 2011
Volume 52, Issue 14
Free
ARVO Annual Meeting Abstract  |   April 2011
SIRT1 Activators Reduce Reactive Oxygen Species Produced During Oxidative Stress In RGC-5 Cells
Author Affiliations & Notes
  • Zoe D. Fonseca-Kelly
    Ophthalmology, University of Pennsylvania Scheie Eye Institute, Philadelphia, Pennsylvania
  • Reas K. Sulaimankutty
    Ophthalmology, University of Pennsylvania Scheie Eye Institute, Philadelphia, Pennsylvania
  • Pegah Safabakhsh
    Ophthalmology, University of Pennsylvania Scheie Eye Institute, Philadelphia, Pennsylvania
  • Kenneth S. Shindler
    Ophthalmology, University of Pennsylvania Scheie Eye Institute, Philadelphia, Pennsylvania
  • Footnotes
    Commercial Relationships  Zoe D. Fonseca-Kelly, None; Reas K. Sulaimankutty, None; Pegah Safabakhsh, None; Kenneth S. Shindler, Sirtris, a GSK Company (F, R)
  • Footnotes
    Support  NIH Grants EYNIH Grants EY015098 and EY019014; National Multiple Sclerosis Society Grant RG 4214-A-1; Research to Prevent Blindness; Sirtris, a GSK Company; and the F. M. Kirby Foundation
Investigative Ophthalmology & Visual Science April 2011, Vol.52, 5909. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Zoe D. Fonseca-Kelly, Reas K. Sulaimankutty, Pegah Safabakhsh, Kenneth S. Shindler; SIRT1 Activators Reduce Reactive Oxygen Species Produced During Oxidative Stress In RGC-5 Cells. Invest. Ophthalmol. Vis. Sci. 2011;52(14):5909.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: : Optic neuritis (ON) is an inflammatory demyelinating disease of the optic nerve. We identified several SIRT1 activators that prevent retinal ganglion cell (RGC) loss in mice with ON. SIRT1 is a member of a conserved gene family (sirtuins) encoding NAD+-dependent deacetylases. Sirtuins deacetylate many protein targets, and it has been shown in other systems that activation increases mitochondrial function and reduces oxidative stress. We hypothesize that treatment with SIRT1 activators during ON increases SIRT1 activity in RGCs, thereby increasing mitochondrial function and reducing accumulation of reactive oxygen species (ROS) that can lead to cell death. Here, we examine whether SIRT1 activators can reduce ROS and promote mitochondrial function in retinal cells in vitro.

Methods: : Cultured RGC-5 cells were stressed by removal of serum or addition of doxorubicin (50µM) for 24 hrs and subsequently treated with vehicle or increasing concentrations of SIRT1 activators (0 - 100µM) for 24 hrs. Cells were stained with MitoSOXTM Red (Invitrogen) to detect the ROS superoxide, and imaged by fluorescent microscopy. Cells were also harvested for protein extraction or RNA isolation and cDNA synthesis. Expression levels of SIRT1 and PGC-1α, a co-enzyme involved in mitochondrial function, were measured by Real Time PCR and Western blotting.

Results: : Removal of serum from the cell culture medium resulted in oxidative stress, as detected by accumulation of MitoSOX Red positive staining ROS in RGC-5 cells. There was a significant reduction in the levels of MitoSOX Red positive ROS in RGC-5 cells that were treated with SIRT1 activators for 24 hrs compared to untreated cells that were stressed by removal of serum. Similar oxidative stress is induced with doxorubicin administration. Treatment of RGC-5 cells with SIRT1 activators for 24 hours after doxorubicin exposure led to an increase in both SIRT1 and PGC-1α expression compared to untreated cells.

Conclusions: : Results show that SIRT1 activators reduce ROS levels in a retinal cell line following induction of oxidative stress. Treatment with SIRT1 activators under oxidative stress conditions resulted in an increase in the level of SIRT1 gene expression, as expected, and also induced increased PGC-1α expression under the same conditions. These results support the hypothesis that SIRT1 activators reduce ROS accumulation in RGCs by promoting increased mitochondrial function.

Keywords: neuroprotection • neuro-ophthalmology: optic nerve • ganglion cells 
×
×

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.

×