April 2010
Volume 51, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2010
X-Box Binding Protein 1 is a Novel Regulator of Anti-Oxidant Genes in the RPE
Author Affiliations & Notes
  • Y. Zhong
    Department of Medicine Endocrinology, Harold Hamm Oklahoma Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
  • J. Li
    Department of Medicine Endocrinology, Harold Hamm Oklahoma Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
  • J. Wang
    Department of Medicine Endocrinology, Harold Hamm Oklahoma Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
  • Y. Le
    Department of Medicine Endocrinology, Harold Hamm Oklahoma Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
  • S. Zhang
    Department of Medicine Endocrinology, Harold Hamm Oklahoma Diabetes Center, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
  • Footnotes
    Commercial Relationships  Y. Zhong, None; J. Li, None; J. Wang, None; Y. Le, None; S. Zhang, None.
  • Footnotes
    Support  NIH grant P20RR024215, JDRF grant 5-2009-475, and a research award from OCAST
Investigative Ophthalmology & Visual Science April 2010, Vol.51, 1427. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Y. Zhong, J. Li, J. Wang, Y. Le, S. Zhang; X-Box Binding Protein 1 is a Novel Regulator of Anti-Oxidant Genes in the RPE. Invest. Ophthalmol. Vis. Sci. 2010;51(13):1427.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: : Oxidative damage of the retinal pigment epithelium (RPE) is a significant pathogenic factor of age-related macular degeneration (AMD). Identifying key regulators of the anti-oxidant defense system can provide critical information for developing therapeutic modalities to prevent or halt the development and progression of AMD. X-box-binding protein (XBP1) is a bZIP transcription factor that induces genes involved in multiple cellular processes, such as biogenesis of the endoplasmic reticulum (ER), protein folding and lipogenesis. The purpose of this study is to investigate the role of XBP1 in the regulation of the anti-oxidant system and oxidative stress in the RPE.

Methods: : Human RPE (ARPE-19) cells were transfected with siRNA specific for XBP1 or control siRNA for 24 h. The mRNA and protein expressions of anti-oxidant genes were examined by real-time PCR and Western blot analysis, respectively. Intracellular superoxide (O2-) and reactive oxygen species (ROS) were determined by dihydroethidium (DHE) and dichlorofluorescein (DCF) fluorescence. Cell viability was determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay.

Results: : Depletion of XBP1 significantly decreased the mRNA expression of anti-oxidant genes, including nuclear-factor-E2-related factor 2 (Nrf2), superoxide dismutase (SOD1 and SOD2), catalase, and glutathione synthase, in human ARPE-19 cells. Decreased protein levels of Nrf2 and SOD2 in XBP1-deficient cells were confirmed by Western blot analysis. These changes coincided with increased levels of intracellular O2- and ROS. In addition, depletion of XBP1 significantly decreased cell viability in ARPE-19 cells.

Conclusions: : Our results suggest XBP1 is a novel transcription factor coordinating the cellular protective system in the RPE. Insight into the mechanisms of XBP1 on regulation of anti-oxidant genes and developing XBP1-based therapeutic strategies may provide novel approaches to prevent and treat AMD.

Keywords: retinal pigment epithelium • antioxidants • age-related macular degeneration 
×
×

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.

×