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Lens opacification and H2O2 elevation induced by a tumor promoter
J J Ye1, K Frenkel, J A Zadunaisky
1Department of Physiology, New York University Medical Center, NY 10016.
Lens and Eye Toxicity Research
|January 1, 1992
Summary
12-O-tetradecanoylphorbol-13-acetate (TPA) causes bovine lens opacity and increases hydrogen peroxide (H2O2) levels. Epigallocatechin gallate (EGCG) and sarcophytol A prevent TPA-induced opacity and H2O2 elevation.
Area of Science:
- Ophthalmology
- Biochemistry
- Toxicology
Background:
- Lens opacity, a leading cause of blindness, can be induced by various chemical agents.
- Hydrogen peroxide (H2O2) is implicated in oxidative stress and cellular damage within the lens.
Purpose of the Study:
- To investigate the effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on bovine lens opacity and H2O2 levels.
- To evaluate the protective effects of anti-tumor promoting agents against TPA-induced lens opacification.
Main Methods:
- Whole bovine lenses were incubated with varying concentrations of TPA.
- Hydrogen peroxide (H2O2) levels and lens opacity were measured.
- Lenses were preincubated with epigallocatechin gallate (EGCG) or sarcophytol A before TPA treatment.
Main Results:
- TPA induced significant lens opacity within 24 hours in a dose-dependent manner.
- TPA treatment led to a four-fold increase in lens H2O2 concentration.
- Preincubation with EGCG or sarcophytol A inhibited TPA-mediated opacification and suppressed H2O2 elevation.
Conclusions:
- TPA is a potent inducer of bovine lens opacity, associated with increased H2O2 levels.
- Epigallocatechin gallate (EGCG) and sarcophytol A demonstrate protective effects against TPA-induced oxidative stress and lens damage.
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