Hydrocortisone decreases retinal endothelial cell water and solute flux coincident with increased content and decreased phosphorylation of occludin
Hydrocortisone decreases retinal endothelial cell water and solute flux coincident with increased content and decreased phosphorylation of occludin
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DOI：
10.1046/j.0022-3042.2001.00740.x
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发表时间：
2002-02-01
影响因子：
4.7
通讯作者：
Scaduto, RC
中科院分区：
文献类型：
--
作者：
Antonetti, DA;Wolpert, EB;Scaduto, RC
皮质类固醇提供了一种有效的治疗，以减少水肿的条件下，血脑或血视网膜屏障受损。然而，关于这些激素影响内皮细胞功能的机制知之甚少。我们假设氢化可的松会减少水和溶质穿过牛视网膜内皮细胞（BREC）单层的运输，与紧密连接蛋白occludin的变化一致。用103 nM氢化可的松处理BREC两天显著降低了水和溶质跨细胞单层的转运。在基于SDS或尿素的缓冲液中提取的闭合蛋白的免疫印迹分析分别显示含量增加1.65倍或2.57倍。通过实时PCR观察到闭合蛋白mRNA的类似两倍增加。免疫细胞化学显示，氢化可的松显着增加occludin和ZO-1染色在细胞边缘。此外，4小时的氢化可的松治疗显着，减少occludin磷酸化。据我们所知，这是第一个例子，一个调节减少occludin磷酸化与增加的屏障性能。总之，氢化可的松直接影响视网膜内皮细胞的屏障特性，与occludin含量、磷酸化和紧密连接组装的变化一致。局部氢化可的松治疗可作为糖尿病视网膜水肿患者的治疗选择。
Corticosteroids provide an effective treatment to reduce edema for conditions in which the blood-brain or blood-retinal barrier is compromised. However, little is known about the mechanism by which these hormones affect endothelial cell function. We hypothesized that hydrocortisone would reduce transport of water and solutes across bovine retinal endothelial cell (BREC) monolayers coincident with changes to the tight junction protein occludin. Treatment of BREC with 103 nM hydrocortisone for two days significantly decreased water and solute transport across cell monolayers. Immunoblot analysis of occludin extracted in SDS or Urea based buffers revealed a 1.65- or 2.57-fold increase in content, respectively. A similar two-fold increase in occludin mRNA was observed by real-time PCR. Immunocytochemistry revealed hydrocortisone dramatically increased both occludin and ZO-1 staining at the cell border. Additionally, 4 h of hydrocortisone treatment significantly, reduced occludin phosphorylation. To our knowledge, this is the first example of a regulated decrease in occludin phosphorylation associated with increased barrier properties. In conclusion, hydrocortisone directly affects retinal endothelial cell barrier properties coincident with changes in occludin content, phosphorylation and tight junction assembly. Localized hydrocortisone therapy may be developed as a treatment option for patients suffering from retinal edema due to diabetes.