Oxidant-induced apoptosis in cultured human retinal pigment epithelial cells.
Invest Ophthalmol Vis Sci
; 40(5): 959-66, 1999 Apr.
Article
in En
| MEDLINE
| ID: mdl-10102293
ABSTRACT
PURPOSE:
To determine the mechanism of oxidant-induced cell death in cultured human retinal pigment epithelium (hRPE).METHODS:
Cultured hRPE cells were treated with different concentrations of a chemical oxidant, t-butylhydroperoxide (tBH), for different periods of time. Apoptosis was determined with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) and flow cytometry. Mitochondrial membrane potential (mtdelta psi) was measured by rhodamine 123 staining and subsequent flow cytometry. Release of mitochondrial cytochrome c (cyt c) and cleavage of procaspase 3 and caspase substrates were determined by western blot analysis.RESULTS:
t-Butylhydroperoxide caused time- and dose-dependent activation of apoptosis in hRPE, indicated by characteristic morphologic changes; TUNEL-positive labeling; phosphatidylserine (PS) exposure; and procaspase 3, poly(ADP-ribose)polymerase, lamin, and tubulin cleavage. An early decrease of mtdelta psi was observed before caspase activation, together with the release of mitochondrial cyt c.CONCLUSIONS:
Results indicate that tBH can induce apoptosis in hRPE, probably by triggering the mitochondrial permeability transition, which results in swelling and release of mitochondrial intermembrane proteins.
Search on Google
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pigment Epithelium of Eye
/
Apoptosis
/
Tert-Butylhydroperoxide
Limits:
Aged
/
Humans
/
Middle aged
Language:
En
Journal:
Invest Ophthalmol Vis Sci
Year:
1999
Document type:
Article