GLP-1(1~37) 诱导人类胚胎小肠 上皮细胞表达胰岛素

胶原酶消化法分离培养人类胚胎小肠的上皮细胞，应用胰高血糖素样肽 1 (glucagon-like peptide 1 (1~37),GLP-1) 诱导小肠上皮细胞向胰岛素分泌细胞分化，免疫组化方法对分化的和未分化的细胞进行鉴定， RT-PCR 检测胰岛内分泌细胞相关基因的表达 . 结果成功分离培养出人类小肠上皮细胞，免疫组化证明细胞表达小肠上皮的标志物细胞角蛋白 18 和 19 ，同时细胞也表达胰高血糖素和生长抑素，但无胰岛素表达 . GLP-1(1~37) 诱导小肠上皮细胞 6 天， RT-PCR 显示胰十二指肠同源异型基因盒 1 (pancreatic duodenal homeobox-1 ， PDX-1) 、葡萄糖转运蛋白 2 (glucose transporter-2 ， GLUT-2) 和胰岛素基因均有表达，免疫组化也检测到胰岛素阳性小肠上皮细胞 . 未用 GLP-1(1~37) 诱导小肠上皮细胞为对照的 RT-PCR 显示 PDX-1 、 GLUT-2 也表达，但无胰岛素 mRNA 和蛋白质的表达 . 研究表明 GLP-1(1~37) 能够诱导人类胚胎小肠上皮细胞向胰岛素分泌细胞分化 .

Glucagon-like Peptide 1 (1~37) Induces Human Embryonic Intestinal Epithelial Cells Into Insulin-positive Cells

Human embryonic intestinal tissues were digested by collagenase, epithelial cells were cultured, glucagon-like peptide 1(1~37) was adapted to induce human embryonic intestinal epithelial cells (hEIECs) to differentiate, and hEIECs without GLP-1 induction were set as control. hEIECs were successfully isolated and cultured, they were stained by cytokeratin 18 and cytokeratin19, the marker for intestinal epithelial cells; they were also stained by somatostatin and glucagon, the hormones secreted by endocrinal cells from pancreas, but they were negative for insulin. After GLP-1(1~37) induction for 6 days, insulin-positive cells could be identified in intestinal epithelial cells by immunocytochemistry and RT-PCR showed that these cells expressed pancreatic duodenal homeobox-1 (PDX-1), glucose transporter-2 (GLUT-2) and insulin. No insulin-positive cells were identified in the control (no GLP-1(1~37) induction), RT-PCR showed that the control expressed PDX-1 and GLUT-2, but not insulin. The findings suggest that GLP-1(1~37) could induce insulin production in developing human embryonic intestinal epithelial cells in vitro, and GLP-1(1~37) may represent a new therapeutic approach to diabetes mellitus.