【摘要】 为探究绿茶粉改善免疫应激小鼠肠道屏障功能的作用机制。选取72只三周龄SPF级C57BL/6雄鼠,对其适应性喂养3 d后随机分成Ⅰ组(阴性对照)、Ⅱ组(阳性对照)、Ⅲ组(添加抗生素)、Ⅳ组(添加1%绿茶粉+茶多酚)、Ⅴ组(添加2%绿茶粉+茶多酚)和Ⅵ组(添加3%绿茶粉+茶多酚),每组3个重复,每个重复4只。在小鼠45 d时,Ⅰ组腹腔注射生理盐水,Ⅱ、Ⅲ、Ⅳ、Ⅴ和Ⅵ组按10μL/g的剂量腹腔注射大肠杆菌脂多糖。注射5 h后采集血液及组织器官。采用RT-PCR测定肠上皮紧密连接蛋白ZO-1、Occludin和Claudin蛋白相对表达量; ELISA法测定血清中IgA、IgG、IgM、肠道sIgA和血浆内毒素含量。结果表明,与Ⅱ组相比,添加茶多酚的绿茶粉能显著降低小鼠血浆内毒素的含量,促进血清中IgA、IgG、IgM和肠道sIgA分泌,同时增加肠上皮紧密连接蛋白ZO-1、Occludin和Claudin蛋白相对表达量。本研究表明,绿茶粉可以通过促进肠上皮紧密连接蛋白ZO-1、Occludin和Claudin蛋白相对表达量,修复肠道屏障,增强免疫应激小鼠的体液免疫,从而减轻肠道炎症,达到保护肠道的作用。更多还原

【Abstract】 The aim of this study was to investigate the mechanism of green tea powder in improving intestinal barrier function in mice with immune stress. After 3 days adaptive feeding,72 SPF C57BL/6 mice (three-weekold) were randomly allocated into group Ⅰ (negative control),group Ⅱ (positive control),group Ⅲ (added antibiotics),and group Ⅳ (add 1% green tea powder + tea polyphenol),Ⅴ group (add 2% green tea powder + tea polyphenol) and Ⅳ group (add 3% green tea powder + tea polyphenol),3 replicates in each group,4 replicates per. At the ages of 45 days,Group Ⅰ was intraperitoneally injected with normal saline,and groups Ⅱ,Ⅲ,Ⅳ,Ⅴ and Ⅵ were intraperitoneally injected with E. coli lipopolysaccharide at a dose of 10 μL/g. Blood and tissues were collected at 5 hours later. Determination of small intestinal epithelial tight junction protein ZO-1,rat Occludin and Claudin protein expression by RT-PCR; Determination of serum IgA,IgG,IgM,s IgA and intestinal endotoxin concentration in plasma by ELISA. The test results showed that compared with groups Ⅱ,green tea powder can significantly reduce the content of plasma endotoxin in mice,IgA,IgG,IgM and promote intestinal secretion of s IgA in serum,and increase intestinal epithelial tight junction protein ZO-1,Occludin and Claudin protein relative expression. The expression of green tea powder can tight junction proteins ZO-1,Occludin and Claudin protein by promoting the amount of intestinal epithelial repair damaged intestinal barrier function,immune suppression mice humoral immune function,reduce intestinal inflammation,protect the intestinal barrier function.更多还原