1,25-二羟基维生素D_3对肠黏膜屏障的保护作用及机制探讨  

Protective effect of 1,25-dihydroxyvitamin D_3 on intestinal mucosa barrier and its mechanism

作　　者：赵红伟[1] 韩华[1] 岳月红[1] 

机构地区：[1]河北省人民医院,石家庄050051

出　　处：《山东医药》2016年第34期14-16,共3页Shandong Medical Journal

摘　　要：目的观察1,25-二羟基维生素D3[1,25-(OH)_2VitD_3]对肠黏膜屏障的保护作用,并探讨其可能的机制,为其在结肠炎治疗中的应用提供依据。方法培养结肠癌Caco-2细胞,模拟人小肠上皮细胞单层细胞屏障;将细胞随机分为3组,A组不处理,B组加2%右旋葡聚糖硫酸钠(DSS)1 m L模拟结肠炎损伤,C组先用10-8mmol/L的1,25-(OH)_2VitD_3处理24 h再加入DSS 1 m L,干预后培养1 h。透射电镜下观察Caco-2单层细胞屏障超微结构变化,采用免疫荧光染色法检测紧密连接蛋白claudin-1、zo-1和occludin的表达。结果透射电镜下,A组细胞顶部出现排列整齐、分化良好的微绒毛状结构,相邻细胞间的顶端呈现紧密连接样结构;B组细胞局部微绒毛消失或减少,紧密连接样结构消失;C组细胞微绒毛分化较B组好,相邻细胞间的局部微绒毛消失不明显。免疫荧光染色显示,A组3种紧密连接蛋白荧光条带连续完整,荧光强度高;B组紧密连接蛋白荧光条带断续不完整,荧光强度弱;C组紧密连接蛋白荧光条带较清晰连续,且荧光强度增强。结论 1,25-(OH)_2VitD_3可通过增加细胞间紧密连接蛋白的表达发挥其对肠黏膜屏障的保护作用,为其在结肠炎中的应用提供了理论依据。Objective To observe the protective effect and the mechanism of 1,25-dihydroxyvitamin D_3[1,25-（ OH）_2VitD_3]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 assigned 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）_2VitD_3（ 10-8mmol / L） for 24 hours,then was incubated with 1 m L 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 immunofluorescence. 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 microvilli 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 incomplete,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）_2VitD_3 may protect the intestinal mucosa barrier by increasing intercellular 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 

分 类 号：R977.24[医药卫生—药品]