摘要
Abstract
Objective To observe the protective effect and the mechanism of 1,25-dihydroxyvitamin D3 [1,25-(OH)2 VitD3 ]on intestinal mucosa barrier and to provide the basis for its application in the treatment of colitis.Methods Caco-2 cells were cultivated for human intestinal epithelial cell monolayer cell barrier.These cells were randomly as-signed to three group:groups A,B and C.Group A was not treated,group B was treated with 2% DSS to establish colitis model and group C first was treated with 1,25-(OH)2 VitD3 (10 -8 mmol/L)for 24 hours,then was incubated with 1 mL DSS for one hour.Caco-2 cell monolayers were observed in ultrastructural features by a transmission electron microscope (TEM);and the expression levels of zo-1,claudin-1 and occludin proteins in Caco-2 cells were detected by immunofluo-rescence.Results There were well-differentiated microvilli structures which were also in good order at the top of cells in the group A,and there was also closely connection between adjacent cells at the top of the structure;while part of the mi-crovilli disappeared or reduced in the group B;the microvilli of cells in the group C were more well-differentiated that those of group B,but part of microvilli disappeared.Immunofluorescence staining showed that in the group A,three kinds of tight junction protein fluorescence strips were complete,and had high fluorescence intensity;those in the group B were incom-plete,and the fluorescence intensity was weak;and those in the group C were clear and continuous,and the fluorescence intensity was enhanced.Conclusion 1,25-(OH)2 VitD3 may protect the intestinal mucosa barrier by increasing intercellu-lar tight junction protein expression which also provides the basis for its application in the treatment of colitis.关键词
结肠炎/1,25-二羟基维生素 D3/紧密连接/屏障功能Key words
colitis/1,25-dihydroxyvitamin D3/tight junction/barrier function分类
医药卫生
