体外培养人晶状体上皮细胞HSP27的表达(英文)

Expression of heat shock protein 27 in in vitro cultured human lens epithelial cells

背景:晶状体独特的解剖位置使其长期暴露于应激环境中。但环境应激能否引起人晶状体上皮细胞中热休克蛋白表达增加?并且这种合成的增加是发生在转录水平,还是在翻译水平,至今尚不知。目的:观察在高温、氧化应激条件下,HSP27在人晶状体上皮细胞中的表达和定位情况。探讨白内障的发病机制。方法:体外培养人晶状体上皮细胞,分别在高温(45℃)、氧化(50mmol/LH2O2)条件下培养30min后,恢复至正常条件。于0,2,4,6,16,24h不同时间段,采用免疫细胞化学、RT-PCR法检测HSP27的表达情况。结果与结论:晶状体上皮细胞在生理和应激情况下均有HSP27的表达。热休克和氧化应激后2h导致HSP27mRNA和蛋白表达明显增加,6h达最高峰,16h仍维持在较高水平。应激导致的HSP27蛋白阳性颗粒由胞浆转移至胞核,并随着时间逐渐转移回胞浆。证实晶状体上皮细胞中存在HSP27。应激情况下,诱导HSP27合成增加,其作为一种对抗应激的蛋白质可能对晶状体上皮细胞起着重要的保护作用。

BACKGROUND： Special anatomical location makes eye lens expose to stressful situation in a long term. Whether the environmental stress can up-regulate the expression of heat shock proteins in human lens epithelial cells？ Whether the synthesis increase occurs in the level of transcription or translation, remains unclear. OBJECTIVE： To observe the expression and location of heat shock protein 27 （HSP27） in human lens epithelial cells under the conditions of high temperature and oxidative stress, and to investigate the pathogenesis of the cataract. METHODS： Human lens epithelial cells cultured in vitro were exposed to heat （45 ℃） and oxidative stress （50 mmol/L H2O2） for 30 minutes, respectively, then allowed to recover normal conditions. At different intervals （0, 2, 4, 6, 16, 24 hours）, immunocytochemistry and reverse transcription polymerase chain reaction were used to determine the expression and localization of HSP27. RESULTS AND CONCLUSION： HSP27 was shown to express in both physiological and stressful conditions. The expressions of HSP27 mRNA and protein were remarkably increased at 2 hours following heat and oxidative stress, and reached the peak at 6 hours. HSP27 could maintain a high level for 16 hours. The stress-induced HSP27 protein positive particles transferred from the cytoplasm to the nucleus, and gradually shift back to the cytoplasm along time. It is proved that HSP27 exists in lens epithelial cells and can be increased after stress. The data suggested it may play an important protective role in lens epithelial cells in respond to cellular stress.