Effects of high-fat diet on islet function and TCF7L2/GLP-1 in pancreatic tissues of mice
Objective To investigate the effects of high fat diet(HFD)on islet function and the expressions of transcription factor 7-analogue 2(TCF7L2)and glucagon-like peptide-1(GLP-1)in pancreatic tissue of mice.Methods Thirty mice were randomized into two groups:normal control(NC)group and HFD group,and the mice in two groups were fed with ordinary diet or 60％high fat diet to induce the type 2 diabetes mellitus(T2DM)model,respectively.After continuous feeding for 24 weeks,the differences in body weight,islet function and other related indicators were compared between two groups.The blood glucose levels of mice were detected by glucose tolerance test,insulin tolerance test and fasting blood glucose test at different time points.The levels of insulin,GLP-1,high density lipoprotein(HDL-C),low density lipoprotein(LDL-C),total cholesterol(TC)and triglyceride(TG)in plasma of mice were detected by ELISA kit.The protein levels of TCF7L2,GLP-1 and glucagon-like peptide-1 receptor(GLP-1 R)in pancreatic tissues of mice were detected by immunohistochemistry and Western blot.The mRNA levels of TCF7L2,GLP-1 and GLP-1 R were tested by quantitative real time polymerase chain reaction assay.Results Compared with NC group,the body weight was significantly increased in HFD group(P＜0.01),and the glucose tolerance and the insulin tolerance of mice were significantly impaired(P＜0.05).Compared with NC group,the contents of fasting HDL-C,LDL-C,TC,TG,blood glucose,and insulin were significantly upregulated in HFD group(P＜0.05).The mRNA and protein expression levels of TCF7L2,GLP-1 and GLP-1 R in HFD group were significantly decreased compared to NC group(P＜0.01).Moreover,compared with NC group,the pancreatic islets of mice in HFD group were irregular in shape,enlarged in size,and the blood vessels were increased in the number,and significantly dilated and congested.Conclusion In high-fat T2DM mice,the morphology of pancreatic islet changes,the islet function decreases,TCF7L2 expression level decreases,and GLP-1 and GLP-1 R expression levels decrease simultaneously.
type 2 diabetes mellitusTCF7L2GLP-1pancreasinsulin
国家科技期刊平台
NSTL
万方数据
