Decreased expression of peroxiredoxins in Fuchs' endothelial dystrophy

Invest Ophthalmol Vis Sci. 2008 Jul;49(7):2956-63. doi: 10.1167/iovs.07-1529. Epub 2008 Mar 31.

Abstract

Purpose: To compare the relative expression of peroxiredoxin (Prx) proteins in normal human corneal endothelium with endothelium in corneas affected by Fuchs' endothelial dystrophy (FED) and between normal human endothelium and epithelial/stromal tissue.

Methods: Human corneal endothelial cell-Descemet's membrane (HCEC-DM) complexes from normal and FED corneal buttons were dissected from the epithelium/stroma. For proteomic analysis, HCEC-DM protein extracts were separated by using two-dimensional gel electrophoresis. Relative differences in protein spot density was analyzed. Proteins of interest, including Prx isoforms, were identified by MALDI-TOF (matrix-assisted desorption ionization-time of flight) mass spectrometry. Western blot analysis compared the relative expression of Prx isoforms in normal and FED endothelium and between normal endothelium and normal epithelium/stroma. Expression of Prx-2 mRNA was compared by using real-time PCR.

Results: Proteomic analysis identified differences in the relative expression of Prx isoforms between normal and FED endothelium. Western blot analysis confirmed that expression of Prx-2, -3, and -5 was significantly decreased (P < 0.05) in FED cells. Normal HCECs expressed significantly (P < 0.05) higher levels of Prx-2 and -3 than did the epithelium/stroma. Expression of Prx-5 was not significantly different (P > 0.05) in the endothelium versus the epithelium/stroma. Real-time PCR analysis revealed that Prx-2 mRNA was significantly decreased (P = 0.027) in FED samples.

Conclusions: Prx proteins were identified in human corneal endothelium. The fact that Prx-2 and -3 were expressed at significantly higher levels in HCEC-DM compared with the epithelium/stroma reflects the different physiologic activities of individual corneal cell types. Significantly decreased expression of Prx-2, -3, and -5 in FED may suggest an alteration in the ability of endothelial cells to withstand oxidant-induced damage and may be closely related to the pathogenesis of this disease.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Blotting, Western
  • Corneal Stroma / metabolism*
  • Down-Regulation*
  • Endothelium, Corneal / metabolism*
  • Epithelium, Corneal / metabolism*
  • Female
  • Fuchs' Endothelial Dystrophy / metabolism*
  • Humans
  • Male
  • Middle Aged
  • Peroxiredoxin III
  • Peroxiredoxins / metabolism*
  • Protein Isoforms / metabolism
  • Proteomics
  • Reference Values

Substances

  • Protein Isoforms
  • PRDX2 protein, human
  • PRDX3 protein, human
  • PRDX5 protein, human
  • Peroxiredoxin III
  • Peroxiredoxins