损伤胰腺组织提取液诱导大鼠骨髓间充质干细胞向胰岛样细胞分化的实验研究

Differentiation of bone mesenchymal stem cells to islet like clusters induced by extract of injured pancreas

目的:探讨胰岛损伤的胰腺组织提取液诱导大鼠骨髓间充质干细胞向胰岛素样细胞分化的作用。方法:通过大鼠腹腔注射链脲佐菌素(STZ)建立1型糖尿病模型,6 d后剥离胰腺提取胰腺组织提取液,与SD大鼠骨髓间充质干细胞共同培养18 d,体外诱导骨髓间充质干细胞向胰岛素分泌细胞分化,RT-PCR法检测诱导分化后细胞的胰岛细胞相关基因的表达,葡萄糖刺激胰岛素释放实验检测诱导后细胞在高糖作用下分泌胰岛素的功能。结果:经损伤胰腺组织提取液诱导后,间充质干细胞在形态上由梭形变成多边、不规则形,且逐渐聚集成岛状。免疫荧光检测诱导细胞的胰岛素表达呈阳性,RT-PCR检测诱导细胞表达胰岛素1(Insl)、胰岛素2(Ins2)、葡萄糖转运子2(Glut-2)、神经源素3(Ngn3)、胰腺十二指肠同源盒1(Pdxl)、同源框蛋白(Isl-1)及脑神经源性分化因子(NeuroD)等胰岛相关基因,且具备高糖诱导促进胰岛素分泌的功能。结论:在损伤胰腺组织提取液诱导下,骨髓间充质干细胞分化为胰岛样细胞,并且具有表达胰岛相关基因和胰岛素分泌功能。

Objective.. To investigate the effect of extract of injured pancreas on inducing the differentiation of bone mesenchymal stem cells （BMSCs） of rats into islet like clusters in vitro. Methods.. Type 1 diabetic model was replicated by peritoneal injection of streptozotocin （STZ） in SD rats,and extract of pancreas was obtained 6 days later. BMSCs of SD rats were isolated and cultured with pancreatic extracts for 18 days in vitro. The expression of islet cell related genes were assessed by reverse trancription-polymerase chain reaction （RT-PCR）,and quantity of insulin secretion after high glucose treatment was measured. Results： The impaired pancreatic extract induced the morphology of BMSCs to form clusters of irregular and polygonal cells. Immunofluorescence assay manifested that they were insulin positive. RT-PCR showed the induced cells expressed pancreatic islet related genes such as Insl, Ins2 ,Ngn3,Pdxl ,Isl-1, NeuroD. Furthermore,it was found that a high glucose concentrated solution was able to induce the secretion of insulin from these cells. Conclusions： Injured pancreatic extracts could induce BMSCs to convert into islet like cell clusters which express insulin related genes, and furthermore the cells possess insulin secretion function.