May 2004
Volume 45, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2004
The cytoprotective role of heat shock proteins and geldanamycin in human retinal pigment epithelial cells subjected to protein phosphatase inhibitor
Author Affiliations & Notes
  • K. Kaarniranta
    Dept of Ophthalmology, Dept of Neuroscience and Neurology,
    Univ of Kuopio, Kuopio, Finland
  • R.K. Sironen
    Dept of Anatomy,
    Univ of Kuopio, Kuopio, Finland
  • J. Huuskonen
    Dept of Neuroscience and Neurology,
    Univ of Kuopio, Kuopio, Finland
  • M.A. Elo
    Dept of Anatomy,
    Univ of Kuopio, Kuopio, Finland
  • H.M. Karjalainen
    Dept of Anatomy,
    Univ of Kuopio, Kuopio, Finland
  • T. Suuronen
    Dept of Neuroscience and Neurology,
    Univ of Kuopio, Kuopio, Finland
  • M. Teräsvirta
    Dept of Ophthalmology,
    Univ of Kuopio, Kuopio, Finland
  • M.J. Lammi
    Dept of Anatomy,
    Univ of Kuopio, Kuopio, Finland
  • H. Uusitalo
    Dept of Ophthalmology,
    Univ of Kuopio, Kuopio, Finland
  • A. Salminen
    Dept of Neuroscience and Neurology,
    Univ of Kuopio, Kuopio, Finland
  • Footnotes
    Commercial Relationships  K. Kaarniranta, None; R.K. Sironen, None; J. Huuskonen, None; M.A. Elo, None; H.M. Karjalainen, None; T. Suuronen, None; M. Teräsvirta, None; M.J. Lammi, None; H. Uusitalo, None; A. Salminen, None.
  • Footnotes
    Support  none
Investigative Ophthalmology & Visual Science May 2004, Vol.45, 3671. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      K. Kaarniranta, R.K. Sironen, J. Huuskonen, M.A. Elo, H.M. Karjalainen, T. Suuronen, M. Teräsvirta, M.J. Lammi, H. Uusitalo, A. Salminen; The cytoprotective role of heat shock proteins and geldanamycin in human retinal pigment epithelial cells subjected to protein phosphatase inhibitor . Invest. Ophthalmol. Vis. Sci. 2004;45(13):3671.

      Download citation file:


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

      ×
  • Supplements
Abstract

Abstract: : Purpose: Reversible protein phosphorylation is an essential mechanism to regulate biological activities of human proteins that affect various various cellular processes, including protein–protein interactions, cell signaling, gene transcription, cell growth and death. Disturbance of cellular homeostasis in retinal pigment epithelial (RPE) cells is involved in development of age–related macular degeneration (AMD). We examined the heat shock protein 70 (Hsp70) stress response and cytotoxicity in human RPE cells subjected to protein phosphatase inhibitor okadaic acid (OA). Moreover, influence of a specific Hsp90 inhibitor geldanamycin (GA), a benzoquinone ansamycin, in cytoprotection was assessed. Methods: Northern blotting was used to analyze the steady–state levels of hsp70 mRNA. Western blotting was used to analysis of Hsp70 protein levels. Lactate dehydrogenase release was measured from culture medium using a non–radioactive cytotoxicity assay. Caspase–3 enzyme activity was measured by assaying the cleavage of a fluorescent peptide substrate, and cellular viability was determined by MTT assay. Results: OA exposure caused Hsp70 stress response prior to the detection of cytotoxicity. Interestingly, GA treatment attenuated clearly OA –induced cytotoxicity in the RPE cells. Alterations in caspase–3 activity were not observed. Conclusions: This study suggests that protein phosphatase inhibitors may present new insights in pathogenesis of AMD. Moreover, Hsp70 and Hsp90 are related to cytoprotection of RPE cells in response to the protein phosphatase inhibitor.

Keywords: retinal pigment epithelium • stress response • apoptosis/cell death 
×
×

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.

×