Study On The Effect Of Phytoestrogen Of Chinese Medicine On Estrogen Receptor Expression In Human Lens Epithelial Cells And Mechanisms Of Signal Transduction

ObjectiveTo investigation the effect of Ecdysterone and Isopsoralen on estrogen receptor(ER) expression in Human Lens Epithelial Cells(HLEC) and the relative Mechanisms of signal transduction,this observation 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.The experiments can be summarized as the following.MethodThis work will use Human Lens Epithelial Cells(HLECs).HLECs were cultured and sub-cultured in vitro.The cultured HLECs were exposed to insult with H₂O₂ at 300μM over a time course of several hours,with and without pretreatment with B-Estradiol(E₂),Ecdysterone (ECR),Isopsoralen(ISR).The HLECs were used for following experiments.1.The changes of the expression of estrogen receptor a(ERa) in HLECs which exposed to insult with H₂O₂,with pretreatment with different concentration of ECR and ISR,were analyzed by flow cytometer(FCM),to study the effect and mechanism of ECR and ISR on antioxidative damage.2.The changes of the expression of estrogen receptorβ(ERβ) in HLECs which exposed to insult with H₂O₂,with pretreatment with different concentration of ECR and ISR,were analyzed by FCM,to study the effect and mechanism of ECR and ISR on antioxidative damage.3.The changes of the expression levels of ERK phosphorylation in HLECs which exposed to insult with H₂O₂,with pretreatment with certain concentration of ECR and ISR, were analyzed by FCM,to study the signal transduction mechanism of ECR and ISR on antioxidative damage.Results1.The expression of ERa was examined in normal HLECs by FCM;The expression of ERa in H₂O₂ group was decreased obviously to compare with control group(p<0.01);The expression of ERa in E₂ group,10^-6,10^-7 and 10^-8mol/L ECR group,10^-5,10^-6 and 10^-7mol/L ISR group were increased obviously to compare with H₂O₂ group respectively(p<0.01);The results indicated concentration-dependent within ECR and ISR respectively.2.The expression of ERβwas examined in normal HLECs by FCM;The expression of ERβin H₂O₂ group was decreased obviously to compare with control group(p<0.01);The expression of ERB in E₂ group,10^-6,10^-7 and 10^-8mol/L ECR group,10^-5,10^-6 and 10^-7mol/L ISR group were increased obviously to compare with H₂O₂ group respectively(p<0.01);The results indicated concentration-dependent within ECR and ISR respectively.3.The expression levels of ERK phosphorylation were examined in normal HLECs by FCM,and peaked at 6h.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 6h when compared with H₂O₂ group respectively (p<0.01),and peaked at 6h.The p-ERK levels of ECR group showed significant increase from 3h when compared with H₂O₂ group respectively(p<0.01),and peaked at 12h.The p-ERK levels of ISR group showed significant increase from 1h when compared with H₂O₂ group respectively(p<0.01),and peaked at 1h.Conclusion1.There were the expression of ERa,ERβand p-ERK in normal HLEC.2.H₂O₂ could decrease the expression of ERaand ERβ.3.E₂,ECR and ISR could increase the expression of ERaand ERβin HLECs insulted with H₂O₂,ECR and ISR showing concentration-dependent,which might be the mechanism of the resistance against oxidant-induced injury by E₂,ECR and ISR in HLECs.4.The expression of p-ERK decreased in HLECs insulted with H₂O₂ with a prolongation of treatment time.5.The expression of p-ERK in E₂,ECR and ISR group peaked at 6h,12h and 1h respectively.6.The resistance against oxidant-induced injury by E2,ECR and ISR in HLECs might relate to ERK/MAPK signaling pathway.