脱氧胆酸促进小鼠肠道Th17浸润参与肠道炎症

Roles of deoxycholic acid in promoting intestinal Th17 infiltration and inducing intestinal inflammation in mice

目的探讨高脱氧胆酸(DCA)对小鼠Th17浸润的影响及对肠道炎症的诱导作用。方法野生型C57BL/6小鼠14只,随机分为普通饮食组和添加0.2%DCA饮食组,每组7只;6周后分别对2组小鼠结肠组织切片进行苏木精-伊红(HE)染色和病理评分,利用流式细胞术分析肠系膜淋巴结Th17比例,免疫荧光染色检测结肠组织Th17浸润改变,实时荧光定量PCR(qPCR)测定小鼠肠道白细胞介素17(IL-17),包括IL-17A、IL-17F等mRNA的表达水平。结果给予小鼠添加0.2%DCA膳食6周后,与普通饮食组相比,其肠道炎症反应增加(P<0.01),并且肠系膜淋巴结Th17比例较普通饮食组升高(P<0.05);添加DCA饮食组小鼠结肠组织浸润的Th17显著增加(P<0.001),肠道促炎性细胞因子IL-17A、IL-17F等表达上调(P<0.05)。结论高水平DCA可促进肠道Th17浸润并参与诱发肠道炎症。

Objective To explore the effect of high level deoxycholic acid(DCA)on the infiltration of intestinal T helper cell 17(Th17)in mice and on the induction of intestinal inflammation.Methods Fourteen wild‐type C57BL/6mice were randomly divided into two groups:the normal diet group and 0.2%DCA‐supplemented diet group,with 7 mice per group.After 6 weeks,colon tissue sections were stained with hematoxylin‐eosin(HE)and evaluated pathologically.Flow cytometry was used to analyze the proportion of Th17 in mesenteric lymph nodes,immunofluorescence staining was adopted to detect Th17 infiltration in colon tissue,and real‐time quantitative PCR(qPCR)was performed to measure the mRNA expressions of interleukin‐17(IL‐17),including IL‐17A and IL‐17F.Results Six weeks of 0.2%DCA‐supple‐mented diet feeding could increase intestinal inflammatory response in mice(P<0.01),and the proportion of Th17 in mesenteric lymph nodes was significantly increased compared to the normal diet group(P<0.05).Th17 infiltration in colon increased significantly upon DCA‐feeding(P<0.001),and the expression levels of pro‐inflammatory cytokine IL‐17A and IL‐17F were significant elevated(P<0.05).Conclusion High level DCA can promote the infiltration of Th17 in intestines and contribute to the induction of intestinal inflammation.