Purpose: To investigate the oxidative modification of lens proteins in the presence of H2O2 in vitro and the protective effect of tea polyphenol(TP) and allitridi.
Methods: Rat lenses were cultured in DMEM medium containing H2O2(1mM) at 37 degrees C in CO2 incubator. Iron and copper salts were added to the medium. At 24 or 48 hours, photographs were recorded the changes in transparency of rat lens and lens proteins were analysed by SDS-PAGE and IEF. TP and allitridi were added to the medium with lens in order to test the antioxidant effects.
Results: Lens opacities occurred at the equatorial region by 24 hours, progressing to totally opaque by 48 hours. SDS-PAGE revealed new bands higher than 43KD were found. In addition the 30KD band disappeared in medium containing copper salt. With addition of TP or allitridi to the culture system, all lens remained transparent.
Conclusion: Exposure rat lens to H2O2 with iron or copper salt resulted in opacification of lens with crosslinking of crystallins and degradation of lens polypeptides. Addition of TP or allitridi prevented the lens from oxidative stress.