Decreased expression of peroxiredoxins in Fuchs' endothelial dystrophy.

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.

• Authors: Ula V Jurkunas, Ian Rawe, Maya S Bitar, Cheng Zhu, Deshea L Harris, Kathryn Colby, Nancy C Joyce
• Journal: Investigative ophthalmology & visual science (Invest Ophthalmol Vis Sci) Vol. 49 Issue 7 Pg. 2956-63 (Jul 2008) ISSN: 1552-5783 [Electronic] United States
• PMID: 18378575 (Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

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

Topics

• 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