胰升糖素样肽1和胃泌素协同促进胰岛素分泌细胞分化

目的胰升糖素样肽1(glucagon-like peptide-1,GLP-1)、胃泌素协同促进大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)转分化的胰岛素分泌细胞(insulin-producing cells,IPCs)分化。方法(1)制备IPCs模型:胰十二指肠同源盒1(pancreatic duodenal homeobox 1,Pdx-1)、神经元素3(neurogenin 3,Ngn3)联合V型肌腱膜纤维肉瘤癌基因同源基因A(V-type tendon fibrosarcoma oncogene homolog A,MafA)共转染BMSCs转分化为IPCs;(2)IPCs分为4组:A组,未诱导组;B组,GLP-1诱导组;C组,胃泌素诱导组;D组,GLP-1联合胃泌素诱导组,高糖培养基培养7 d,RT-PCR检测各组胰岛素2(insulin2)、葡萄糖激酶(GK)、巢蛋白(nestin)、胰升糖素(glucagon)及Pdx-1表达水平,ELISA检测各组胰岛素分泌情况。结果在高糖条件下培养7 d,各组IPCs形态出现明显变化,逐渐聚集并形成散在细胞团块,联合诱导组形成大型细胞团块,双硫棕染色呈红棕色;各组在诱导第0、3、5、7、9天胰岛素分泌水平逐渐提高,且联合诱导组升高最为明显(P<0.05);与A组相比,B、D组Insulin2和GK表达明显上调,D组glucagon表达下调,C组Pdx-1表达下调,glucagon表达上调,(P<0.05);与B组相比,C组insulin2表达下调,glucagon表达水平明显上调,D组insulin2和GK表达水平明显上调,glucagon表达水平下调(P<0.05);与C组相比,D组Pdx-1、insulin2和GK表达水平明显上调,glucagon表达水平下调(P<0.05)。结论GLP-1和胃泌素通过上调insulin2和GK,下调glucagon协同促进IPCs向胰岛β细胞分化。

Glucagon-like peptide-1 and gastrin synergistically promote the differentiation of insulin-producing cells

Objective Glucagon-like peptide-1(GLP-1)and gastrin synergistically promote the differentiation of insulin-producing cells which differentiated from rat bone marrow mesenchymal stem cells(BMSCs).Methods(1)Prepare IPCs model:pancreatic duodenal homeobox 1(Pdx-1),neurogenin 3(Ngn3)combined with V-type tendon fibrosarcoma oncogene homolog A(MafA)co-transfected BMSCs differentiation into IPCs;(2)IPCs were divided into 4 groups:Group A(uninduced group),group B(GLP-1 induction group),group C(gastrin induction group),and group D(GLP-1 combined with gastrin induction group).Cultured in high glucose medium for 7 days,the expression levels of insulin2,Pdx-1,GK,nestin,and glucagon mRNA were detected by RT-PCR.The insulin secretion of each group was detected by ELISA.Results After cultured for 7 days under high glucose conditions,the morphology of IPCs in each induction group changed significantly,gradually aggregated and formed scattered cell masses,and the combined induction group formed large cell masses.The staining of disulfide brown was reddish brown;The levels of insulin secretion increased gradually on the 0,3rd,5th,7th,and 9th day after induction,and the increase was the most significant in the combined induction group(P<0.05).Compared with group A,the expression of insulin2 and GK in group B and D was significantly up-regulated,the expression of glucagon was down-regulated in group D,the expression of Pdx-1 was down-regulated in group C,and the expression of glucagon was up-regulated(P<0.05).Compared with group B,The expression of insulin2 was down-regulated in group C,and the expression level of glucagon was up-regulated.The expression levels of Pdx-1 and Insulin2 were significantly up-regulated in group D,and the expression level of glucagon was down-regulated(P<0.05).Compared with group C,the expression level of Pdx-1,insulin2 and GK was significantly up-regulated in group D,and the expression level of glucagon was down-regulated(P<0.05).Conclusion GLP-1 and gastrin synergistically promote the differentiation of IPCs into isletβcells by up-regulating GK and insulin2 and down-regulating glucagon.