活化蛋白-1在膳食牛磺酸防护视网膜光损伤中的表达变化

Alteration of Actor Protein-1 Expression in Light-damaged Retina Protected by Dietary Taurine

目的探讨膳食牛磺酸防护视网膜光化学损伤的分子机制。方法30只Sprague-Dawley大鼠饲以AIN-93标准饲料或补充4%牛磺酸膳食干预15d,给予(3000±200)lux的持续光照24h,形态测量法观察视网膜外核层厚度,电生理法检测视网膜功能,Western blot或免疫组织化学法检测活化蛋白-1(actor protein-1,AP-1)亚单位c-fos/c-jun蛋白表达,荧光定量PCR法检测其mRNA表达。结果光照能降低视网膜外核层厚度,降低视网膜电图a波和b波的幅度,升高AP-1蛋白和mRNA的表达,4%膳食牛磺酸在转录和翻译水平下调AP-1的表达,有效防护视网膜光化学损伤。结论转录因子AP-1在膳食牛磺酸防护视网膜光损伤中发挥着重要作用。

Objective To investigate the underlying molecular mechanism involving in dietary taurine protecting retina from photochemical damage.Methods Thirty Sprague-Dawley rats fed with or without 4% taurine under AIN-93 diet for 15 d were persistently exposed to fluorescent light（3000±200 lux） for 0-24h.The thickness of outer nuclear layer（ONL）of retinas was measured with morphometry.The retinal function was detected with electrophysiological technique.The expression of actor protein-1（AP-1）subunits c-fos/c-jun protein was analyzed with Western blot or immunohistochemical method,and their mRNA expression determined with quantitative real-time PCR（qRT-PCR）.Results There was a decrease in thickness of ONL, and in amplitude of a- and b- waves of electroretinogram,an increase in protein and mRNA expression of c-fos/c-jun subunits in retinas of rats exposed to light.4% dietary taurine effectively prevented retinal photochemical damage as changes of morphology and electroretinogram（ERG）.Also,the supplementation caused a down-regulation in expression of c-fos/c-jun subunits.Conclusions Transcription factor AP-1 plays a pivotal role in dietary taurine protecting retina from photochemical damage.