基于组学技术研究膳食绿原酸增强肠黏膜屏障的分子机制

The homeostasis of intestinal mucosal barrier is very important for maintaining the health of the body. Dietary phenolic acid (CGA) has excellent protective effect on intestinal mucosal barrier. Our previous works show that chlorogenic acid can reduce intestinal permeability in rat and increase the intestinal tight junction (TJ) protein level of LPS-stressing rats, inhibit the activation of myosin light chain kinase in colitis, reduce myosin light chain phosphorylation and increased the expression of Occludin and Claudin-1. However, the molecular mechanism of CGA enhancing intestinal mucosal barrier and epithelial cells TJ are still unclear..In this study, we will investigate variation of metabolites of CGA in lumen and microbiota-derived metabolites in mucus layer, the response of mucin and commensal bacteria in the mucus layer, differentially expressed proteins and related signaling pathways involved in CGA enhancing intestinal mucosal barrier, and the role of protein kinase C and the Rho-associated coiled-coil-containing protein kinase on epithelial cell tight junction, and the dynamics of ZO-1 with temporal and spatial variation. It will elucidate the molecular mechanism of CGA on intestinal mucosal barrier. The study will provide a new research pathway and basis for the quality evaluation, biological activity of phenolic acids and protective effect of intestinal health.

肠黏膜屏障对维持机体健康很重要，膳食酚酸具有保护肠黏膜屏障作用。我们前期结果表明：绿原酸（CGA）可降低脂多糖应激大鼠肠道通透性，增加黏膜紧密连接（TJ）蛋白表达；抑制结肠炎大鼠肠黏膜肌球蛋白轻链（MLC）激酶表达，降低MLC磷酸化，增加TJ蛋白Occludin和Claudin-1表达。然而，CGA增强肠黏膜上皮细胞TJ的分子机制仍不清楚。.本项目拟通过动物与细胞模型，运用免疫印迹、分子生物学和iTRAQ标记联合LC-MS/MS组学技术等，在CGA增强肠道黏膜屏障功能基础上，分析CGA肠腔代谢物和黏液层菌群衍生代谢物的变化，黏液层中黏蛋白和共生菌的响应，研究肠上皮细胞差异蛋白和相关信号通路，蛋白激酶C和Rho相关螺旋卷曲蛋白激酶的表达，探讨TJ蛋白ZO-1随时空的表达/组装/迁移及其作用。以期阐明膳食CGA增强肠黏膜屏障的分子机制，将为酚酸活性研究与品质评价和肠道稳态调控提供科学依据。

肠黏膜屏障对维持机体健康很重要，膳食酚酸具有保护肠黏膜屏障作用。我们前期结果表明：绿原酸（CGA）可降低脂多糖应激大鼠肠道通透性，增加黏膜紧密连接（TJ）蛋白表达，增加TJ蛋白Occludin和Claudin-1表达。然而，CGA增强肠黏膜上皮细胞TJ的分子机制仍不清楚。本项目通过动物与细胞模型，运用免疫印迹、分子生物学和LC-MS/MS组学技术等，分析了CGA对肠腔黏液层菌群的调控作用，黏液层及杯状细胞黏蛋白MUC的影响，以及上皮细胞内质网应激水平，初步证实绿原酸通过ROCK1—MLCK—ZO-1—Claudin-1/Occludin路径增强肠上皮细胞紧密连接。初步阐明了膳食CGA增强肠黏膜屏障的分子机制，为酚酸活性研究与品质评价和肠道健康调控提供了科学依据。