Effects Of MAPK Signaling Pathway On The Expression Of Aquaporins Induced By Oxidative Damage In Human Lens Epithelial Cells

Objective: To observe the expression of aquaprin 1(AQP1) and aquaprin 5(AQP5) in human lens capture and human lens epithelial cells(HLECs) and investigate the effects of MAPK(mitogen-activated protein kinase,MAPK)signaling pathway on the expression of AQP1 and AQP5 induced by oxidative damage in HLECs.Methods: Lens capsules from age-related cataract patients after phacoemulsification and donors? eyes were collected. The expression of AQP1 and AQP5 m RNA in the two kind of capsule tissuese was detected by Real-Time Polymerase Chain Reaction(RT-PCR). The protein expression level of AQP1 and AQP5 was detected by immunohistochemistry. HLECs were cultured in vitro. We divided HLECs into control group, stimulated by H2O2 group and inhibitor pretreatment group randomly. Western blot was applied to detect the protein expression level. RT-PCR was used to detect the expression of AQP1 and AQP5 m RNA.Results:(1) In this study we confirmed AQP5 and AQP1 expression in lens capsule tissuse of cataract patients and normal and in HLECs cultured in vitro.(2) H2O2 stimulation can reduce AQP1 and AQP5 m RNA and protein expression, and the difference was statistically significant(P<0.05).(3) The expression of p-ERK, p-p38 was increased induced by H2O2(P<0.05). But the expression of p-JNK was no significantly increased(P> 0.05).(4) The expression of AQP1 in ERK and p38 inhibitor pretreatment group was higher compaired with H2O2 stimulation group(P<0.05). However the expression of AQP5 had no difference in this two group(P> 0.05).Conclusion:(1) AQP5 and AQP1 are expressed in lens epithelial cells. The low expression of AQP5 and AQP1 may have relationship with cataract.(2) The expression of AQP1 and AQP5 is decreased induced by H2O2 in HLECs, and the decrease of AQP1 is induced through ERK and p38 signaling pathway.(3) MAPK signaling pathway has no effect on the exression of AQP5 induced by H2O2 in HLECs.