Abstract:AIM: To investigate the relative mechanisms of signal transduction of isopsoralen(ISR)and ecdysterone(ECR)on phosphorylated extracellular signal-regulated kinase(p-ERK)expression in human lens epithelial cells(HLEC), which will provide a view in better understanding the mechanisms of aged cataract, and provide the experiment bases for the prophylaxis and treatment of aged cataract.
METHODS:Human lens epithelial cells(HLECs)were cultured and sub-cultured in vitro. The cultured HLECs were exposed to H2O2 at 300μmol/L over a time course of several hours, with and without pretreatment with β-Estradiol(E2), ECR, ISR. The HLECs were used for following experiments. The changes of the expression levels of ERK phosphorylation in HLECs which exposed to H2O2, with pretreatment with certain concentration of ECR and ISR, were analyzed by flow cytometer(FCM), the signal transduction mechanism of ECR and ISR on antioxidative damage was studied.
RESULTS: The expression levels of ERK phospho- rylation were examined in normal HLECs by FCM,and peaked at 6 hour. The p-ERK levels of H2O2 group gradually decreased with a prolongation of treatment time. There were significant differences as compared with control group respectively(P<0.01). The p-ERK levels of E2 group gradually increased with a prolongation of treatment time, showed significant increase from 6 hour when compared with H2O2 group respectively(P<0.01), and peaked at 6 hour. The p-ERK levels of ECR group showed significant increase from 3 hour when compared with H2O2 group respectively(P<0.01), and peaked at 12 hour. The p-ERK levels of ISR group showed significant increase from 1 hour when compared with H2O2 group respectively(P<0.01), and peaked at 1 hour.
CONCLUSION:The resistance against oxidant-induced injury by E2, ECR and ISR in HLECs might relate to ERK/MAPK signaling pathway.
