Effects of human glucagon-like peptide-1 analog gene transfection on blood glucose,insulin levels and pancreatic island in diabetic rats / 解放军医学杂志

ABSTRACT

Objective To explore the effects of recombinant expression plasmid of human glucagon-like peptide-1 (hGLP-1) analog gene (2?Val2-hGLP-1) on blood glucose, serum insulin level and pancreatic island in diabetic rats. Methods The diabetic rat model was reproduced by intraperitoneal injection of streptozotocin. The rats were then divided into 3 groups randomly (8 each): recombinant plasmid pIRES2-EGFP/Val2-hGLP-1 transfection group, empty plasmid pIRES2-EGFP transfection group, and diabetic rat model control group. Moreover, 8 untreated SD rats were set as normal control. Each rat in empty plasmid transfection group and recombinant plasmid transfection group was injected via tail vein with 110?g plasmid, whibe those in diabetic model control group and normal control group were treated with equal volume of normal saline solution. Blood glucose and serum insulin levels of rats were determined 30 days after experiment, and glucose tolerance test and insulin tolerance test were performed to estimate insulin sensitivity. The pathological changes in pancreatic island and insulin secretion were evaluated with HE and immunohistochemistry staining, respectively. Results Compare with normal group, diabetic model group and empty plasmid transfection group, the blood glucose level significantly lowered (P0.05). Meanwhile, the insulin secretion was increased and the pathological changes in pancreatic islands were alleviated in recombinant plasmid transfection group compared with that in diabetic model control group. Conclusions hGLP-1 analog gene transfection may be able to promote the proliferation of pancreatic islands and enhance sensitivity to insulin, thus significantly lower blood glucose level and ameliorate the lesion of pancreatic islets in diabetic rats.