Chenodeoxycholic acid improves insulin resistance by FXR-mediated regulation of intestinal GLP-1 in high-fat diet mice
10.16016/j.2097-0927.202309152
- VernacularTitle:鹅去氧胆酸通过FXR调控高脂饮食诱导小鼠肠道GLP-1表达水平改善胰岛素抵抗的作用
- Author:
Pengfei LI
1
;
Ling JIANG
;
Pengfei HOU
;
Niu DONG
;
Mantian MI
;
Long YI
Author Information
1. 400038 重庆,陆军军医大学(第三军医大学)军事预防医学系营养与食品安全研究中心,重庆市医学营养研究中心,营养与健康重庆市重点实验室
- Keywords:
chenodeoxycholic acid;
glucagon-like peptide-1;
farnesoid X receptor;
intraepithelial lymphocytes;
CD26
- From:
Journal of Army Medical University
2024;46(9):952-961
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of chenodeoxycholic acid(CDCA)on the expression of glucagon-like peptide-1(GLP-1)in the intestine of mice induced by high-fat diet(HFD)through farnesoid X receptor(FXR),and investigate the related mechanism.Methods Forty C57BL/6 mice were divided into control group,HFD group,HFD+CDCA group,HFD+Z-Gug(FXR antagonist)group,and HFD+CDCA+Z-Gug group,with 8 animals in each group.During intervention for 8 weeks,body weight and 24-hour food intake were measured every week.At the 8th week,oral glucose tolerance test(OGTT)and intraperitoneal glucose tolerance test(IPGTT)were conducted.After the mice were sacrificed,the serum levels of GLu,TG,CHO,LDL-C and HDL-C were detected;the expression levels of GLP-1 and FXR in intestinal tissues were detected by immunofluorescence assay;and the mRNA levels of TNF-α,IL-6,IL-1β,Gcg and FXR were detected by RT-qPCR;the serum level of GLP-1 was detected by ELISA,and the proportion of intraepithelial lymphocytes(IELs)subsets and the expression of CD26/DPP4 were detected by flow cytometry.Results Compared with the control group,the HFD group had increased body weight,abnormal serum glucose and lipid metabolism,impaired oral glucose tolerance,and weakened secretion of gastrointestinal hormones(P＜0.05),enhanced FXR expression at mRNA and protein levels,declined Gcg mRNA level and GLP-1 secretion level(P＜0.05),increased mRNA levels of intestinal inflammatory factors TNF-α,IL-6 and IL-1β(P＜0.05),raised proportions of TCRαβ+IELs,TCRαβ+CD8αα+IELs,and TCRαβ+CD8αβ+IELs but reduced proportion of TCRγδ+IELs,and increased total CD26/DPP4 expression in IELs(P＜0.05).Compared with the HFD group,HFD+CDCA treatment resulted in significantly increased body weight,impaired oral glucose tolerance,decreased secretion of gastrointestinal hormones,increased FXR mRNA and protein expression,and decreased Gcg mRNA expression and GLP-1 secretion(P＜0.05);decreased proportions of TCRαβ+IELs,TCRαβ+CD8αα+IELs and TCRααβ+CD8αβ+IELs but increased proportion of TCRγδ+ cells in IELs,and increased expression of total CD26/DPP4 in IELs(P＜0.05),which were significantly improved after Z-Gug intervention(P＜0.05).Conclusion CDCA may inhibit the expression and secretion of GLP-1 in intestinal tissue by activating FXR,and reduce the secretion of GLP-1.At the same time,CDCA may inhibit the expression of related inflammatory factors,regulate the proportions of IELs subsets,up-regulate the expression level of CD26/DPP4,promote the degradation of GLP-1 and aggravate insulin resistance.
