Abstract
Abstract: :
Purpose: To evaluate changes in gene expression in experimental glaucoma, using gene microarray analysis. Methods: Glaucoma was induced to right eye of 4 monkeys by repeated argon laser photocoagulation for the trabecular meshwork. At 4weeks after coagulation, monkey retinas were isolated from glaucoma model and control eyes. Poly(A)+ RNA was isolated using FastTrack 2.0 mRNA isolation kit (Invitrogen, Carlsbad, CA). cDNA generation, hybridization, and data collection were performed by Incyte Genomics. Alterations in gene expression were evaluated by reverse transcription of poly(A)+ RNAs in the presence of Cy5 or Cy3 fluorescent labeling dyes followed by hybridization to a human UniGEM Human V ver.2.0 microarray chip. Each chip displays a total of 9182 elements including EST clones. Subsets of genes were selected for further study based on difference between glaucoma and control eyes at more than 1.7. Differential expression of representative selected genes was confirmed by RT-PCR. Results: A monkey eye had an advanced IOP rise (50-60 mmHg) and the C/D ratio was 0.8. Another monkey eye had the middle IOP rise (30-40 mmHg) and cuppng just started. Microarray was performed on these two eyes. Fluorescence intensity was measured for each chip and normalized to the average fluorescence intensity for the entire chip. The values were compared between the glaucoma model retina and the control retina. Approximately 0.6% of the measured genes were either up-regulated or down-regulated in the retina from the glaucoma model eye. For example, some of immuno related genes were up-regulated. Neurofilament was down-regulated and GFAP was up-regulated. It might suggest that the activity of glial cell was enhanced by damage of ganglion cell. Conclusion: Our microarray results suggest that a number of genes are differentially expressed in the glaucoma retina and some of these may play a role in actual glaucoma. So it is necessary to investigate the localization and the function of these proteins by immunohistochemistry, immunoblotting, and cell biology technique.
Keywords: 476 molecular biology • 417 gene/expression • 316 animal model