Downregulation of differentiation specific gene expression by oxidative stress in ARPE-19 cells.
OBJECTIVE
To investigate how the differentiation of ARPE-19 cells affects the relative expression of the FGFR genes in response to oxidative stress.


METHODS
After differentiation in vitro, APRE-19 cells were treated with t-butyl hydroperoxide (tBH) or hydrogen peroxide (H2O2) to induce oxidative stress. Viability and reactive oxygen intermediate (ROI) production were measured using standard assays. The mRNA expression of FGFR1, FGFR2, cellular retinaldehyde-binding protein (CRALBP), RPE65, and heme oxygenase-1 (HO-1) were measured by Northern blot analysis as a function of treatment with tBH and H2O2.


RESULTS
ARPE-19 cells were viable at all tBH concentrations tested but showed progressive loss of viability at concentrations greater than 300 microM H2O2. Differentiated ARPE-19 cells treated with tBH or H2O2 resulted in upregulation of the HO-1 and FGFR1 transcripts. The expression of RPE-differentiated specific genes, including FGFR2, CRALBP, and RPE65 mRNAs, was downregulated with tBH or H2O2 treatment.


CONCLUSIONS
Oxidative stress in differentiated ARPE-19 cells alters the expression of FGFR1, FGFR2, CRALBP, and RPE65 toward levels characteristic of the undifferentiated state. If similar changes take place in vivo, these events could alter the proliferative potential, viability, and even the function of the RPE.
Alizadeh
M
M
Section of Molecular and Cellular Biology, University of California, Davis, USA.
Wada
M
M
Gelfman
C M
CM
Handa
J T
JT
Hjelmeland
L M
LM
D015152:Blotting, Northern; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation; D002460:Cell Line; D015536:Down-Regulation; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism; D051547:Heme Oxygenase-1; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008565:Membrane Proteins; D018384:Oxidative Stress; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics / Q000378:metabolism; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors; D019745:cis-trans-Isomerases; D020122:tert-Butylhydroperoxide / Q000494:pharmacology; D000099178:Retinoid Isomerohydrolase
D002352:Carrier Proteins; D005136:Eye Proteins; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; D006861:Hydrogen Peroxide; D008565:Membrane Proteins; D011506:Proteins; D012333:RNA, Messenger; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor; D019745:cis-trans-Isomerases; D020122:tert-Butylhydroperoxide; D000099178:Retinoid Isomerohydrolase; C020932:11-cis-retinal-binding protein; C496541:HMOX1 protein, human; C496348:FGFR1 protein, human; C496353:FGFR2 protein, human