过氧化氢对人晶状体上皮细胞内细胞质膜微囊蛋白的影响

目的探讨过氧化氢（H2O2）对人晶状体上皮细胞的细胞质膜微囊蛋白（CP）及磷酸化CP-1分布与表达的影响。方法给予人晶状体上皮细胞（SRA01／04）不同浓度及不同时间点的H2O2刺激。用激光共聚焦显微镜和免疫荧光显微镜观察CP及磷酸化CP-1的分布。通过免疫印迹试验观察CP表达水平的变化以及磷酸化CP—1的表达。结果通过激光共聚焦显微镜和荧光显微镜,观察到人晶状体上皮细胞的质膜和细胞质内含有丰富的CP;当给予细胞H2O2刺激后,细胞质内CP的分布增多;当刺激时间达到1h,细胞膜被破坏,但仍可观察到CP的分布情况。此外,H2O2的刺激可以使CP-1发生磷酸化。免疫印迹试验发现,随着H2O2作用时间的延长和刺激浓度的升高,细胞质膜和细胞总蛋白质的CP表达水平呈下调趋势。结论H2O2刺激人晶状体上皮细胞后,CP重新分布并可能破坏了细胞质膜微囊（caveolae）的结构,使得细胞的CP表达下调。细胞质膜微囊和CP可能在人晶状体上皮细胞中具有重要作用。

Experimental study on the effects of hydrogen peroxide on caveolin in human lens epithelial cells

OBJECTIVE: To observe the expression and distribution of caveolin and phosphorylated caveolin-1 in human lens epithelial cells (HLECs) under H(2)O(2) treatment. METHODS: HLECs (SRA01/04) were exposed to different concentrations of H(2)O(2) for different periods of time. The distribution of caveolin and phosphorylated caveolin-1 in H(2)O(2) treated cells was observed by laser scanning confocal microscopy and fluorescence microscopy. Western blot was conducted to analyze the protein expression alterations of caveolin and caveolin-1 phosphorylation. RESULTS: HLECs contained abundant caveolin. Immunofluorescence image of caveolin in cytoplasm increased significantly in H(2)O(2) treated cells. One hour after H(2)O(2) treatment, the cells membranes began to break, whereas the immunofluorescence image of caveolin could still be observed. Caveolin-1 was phosphorylated on tyrosine 14 in HLECs after stimulation with H(2)O(2). Western blot analysis revealed that caveolin protein level was down regulated under H(2)O(2) stress. CONCLUSIONS: The caveolin is redistributed and the caveolae is destroyed in HLECs when stimulated by H(2)O(2). And the caveolin expression also down regulated by H(2)O(2) stimulation. Caveolae and caveolin are likely to play an important role in the HLECs.