Effect Of Anti-apoptosis Drugs On Signal Transduction Of Lens Epithelial Cell Damaged By Oxidative Stress

ObjectiveTo investigate the prevention of anti-apoptosis drugs (sodium ferulate, SF; schisandrin B, Sch B; flos chrysanthemi, FC; semem planagines, SP) on lens epithelial cell (LEC) damaged by oxidative stress, and to study the changes of intracellular-free calcium, cyclic adenosine monophosphate (cAMP) and cyclic guanine monophosphate (cGMP), in order to disclose the mechanism of signal transduction in cellular and molecular level.Methods1. Bovine LEC were primarily cultured and sub-cultured, and used for experiment in generation 3.2. LEC were incubated with hydrogen peroxide (H2O2). Four different concentration drugs (SF 25 u g/ml, 50 u g/ml, 100 u g/mk Sch B 12.5 u g/ml, 25u g/ml, 50 u g/mk FC 0.2 mg/ml, 0.4 mg/ml, 0.8 mg/mk SP 2 mg/ml, 4 mg/ml, 8 mg/ml) were added into the LEC damaged by oxidative stress and incubated for 12, 24 and 36 hours respectively.3. The LEC activities were observed by 3-(4, 5-dimethy-thiazol- 2- yl)-2, 5-diphenyItetrazolium bromide(MTT) assay.4.1ntracellular-free calcium content of LEC were detected by spectrofluorophotometer using Fura-2/AM as an indicator.5. Intracellular cAMP and cGMP concentrations of LEC were determined by radioimmunoassay (RIA).Results1. The results of MTT test shown that the absorbance values(A values ) in LEC of H2O2 groups reduced obviously to compare with control group(P<0.01). The activities of LEC treated with different concentrations of four anti-apoptosisdrugs for different times increased, and showing obvious dose-dependent and time-dependent.2. The intracellular-free calcium contents of LEC in H2O2 group by spectrofluorophotometer increased significantly compared with control group (P <0.01); however, it decreased remarkably in the groups of four anti-apoptosis drugs, showing obvious time-dependent (P<0.01).3. The cAMP concentration of LEC in H2O2 group by radioimmunoassay increased significantly compared with control group (P<0.01); however, it decreased remarkably in the groups of four anti-apoptosis drugs, showing obvious time-dependent (P<0.01).4. The cGMP concentration of LEC in H2O2 group by radioimmunoassay decreased significantly compared with control group (P<0.01); however, it increased remarkably in the groups of four anti-apoptosis drugs, showing obvious time-dependent (P<0.01).Conclusion1. Hydrogen peroxide can restrain the activity of LEC, and increase the intracellular-free calcium content and cAMP level but decrease cGMP level.2. Four anti-apoptosis drugs (SF, Sch B, FC, SP,) can prevent activity of LEC from oxidative damage, decrease the intracellular-free calcium content.3. Four anti-apoptosis drugs (SF, Sch B, FC, SP,) down-regulate cAMP level and up-regulate cGMP level4. Four anti-apoptosis drugs protect LEC from oxidative damages and inhibit apoptosis of LEC. It is possible that the mechanisms of preventing and delaying cataract formation by four anti-apoptosis drugs may be the cross-talk among calcium signal transduction system, cAMP signal transduction system and cGMP signal transduction system.