摘要
目的观察饲料中添加牛磺酸对光化学损伤后大鼠光感受器细胞凋亡的影响,并进一步从氧化应激基因c-fos表达变化角度探讨其防护机制。方法70只SD大鼠随机分为对照组、牛磺酸组。分别喂饲标准饲料或添加4%牛磺酸饲料喂饲15d后接受(3000±200)lx持续0,1,3,6,9,12,24h光照,凋亡细胞原位末端标记法(TUNEL)检测光感受器细胞凋亡情况并计算凋亡指数(AI);RT-PCR法及免疫印迹法检测视网膜内c-fos mRNA以及蛋白表达水平。结果感光细胞凋亡指数随光照时间延长逐渐增加,牛磺酸组AI显著低于对照组(P<0.05),其中光照12h牛磺酸组与对照组AI分别为(12.3±4.7)%和(32.4±6.2)%;视网膜c-fos mRNA光照1h后一过性表达增高,牛磺酸组较对照组低(P<0.05);光照后视网膜c-fos蛋白表达逐渐升高,于3h达峰值,牛磺酸组显著低于对照组(P<0.05)。结论在视网膜光化学损伤条件下,牛磺酸可能通过抑制视网膜c-fos的转录及表达,阻断光感受器细胞凋亡转导从而保护视网膜。
Objective To observe the effect of dietary supplementation with taurine on photoreceptor apoptosis and further investigate ehanges of c-fos expression of rat retina after photochemical damage. Methods Seventy rats were randomly divided into control group （Control） and 4 % taurine supplementation group （Taurine）. The subjects were exposed to （3000 ± 200） lx transmitted by six cold white lights for 0, 1,3, 6, 9, 12, 24 h. The apoptotic photoreceptor cells were deteeted using TUNEL method;Total RNA and protein of retina were extracted;relative c-fos mRNA levels were determined using RT - PCR and c-los protein levels were detected by western - blot analysis. Results With the light exposure time prolonged, apoptosis index （AI） of photoreeeptor cells was elevated, among which the AI of 12h were （ 12.3 ± 4.7） % and （32.4 ±6.2） % in Taurine and control group（P〈 0.05）. The c-fos mRNA of rat retina was transiently induced after one- hour light exposure and it was lower in taurine group （ P 〈 0.05） ; c-fos protein level increased after three hour exposure and it was lower in taurine group （P 〈 0.05）. Conclusion Taurine can partly reduce the transcription and translation of c -fos, which would further inhibit the apoptosis signal transduction and protect the rat retina from photochemical damage.
出处
《中国公共卫生》
CAS
CSCD
北大核心
2007年第1期79-81,共3页
Chinese Journal of Public Health
基金
国家自然科学基金(30200228)
