目的：研究异补骨脂素(Isopsoralen，ISR)和蜕皮甾酮(Ecdysterone，ECR)对经H₂O₂处理的HLEC内磷酸化ERK(p-ERK)的表达，从而探讨雌二醇(β-Estradiol，E₂)，ECR和ISR是否通过启动或干预ERK/MAPK信号转导途径来发挥抗氧化损伤作用，以揭示E₂和ECR及ISR抗氧化损伤的信号转导机制。

方法：本研究采用ECR和ISR与人晶状体上皮细胞(HLEC)共同孵育，以E₂作为阳性对照，再用H₂O₂对HLEC造成氧化损伤后，采用流式细胞术(flow cytometer， FCM)检测不同时段的p-ERK蛋白表达。

结果：正常HLEC内存在p-ERK表达； H₂O₂组p-ERK表达量随时间的延长而减少； E₂和ECR与ISR各组p-ERK表达量分别在1，6，12h达到高峰。

结论：E₂和ECR与ISR的抗氧化损伤作用可能是与ERK/MAPK信号通路有关。

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.