裸质粒介导人胰岛素原突变基因在糖尿病小鼠中的表达和治疗效果

Naked plasmid mediated expression and therapeutical effect of mutant human proinsulin gene in diabetic mice

目的 研究含有人胰岛素原突变基因 (mhINS)的裸质粒在链脲佐菌素诱导的糖尿病小鼠中的表达及其治疗效果。方法 应用放射免疫法检测含有人胰岛素原突变基因的表达质粒pcDNA3 mhINS的L0 2细胞株表达胰岛素情况 ;通过尾静脉大容量快速注射法将其转染到糖尿病小鼠体内 ,利用PCR ,RT PCR检测pcDNA3 mhINS的组织分布及表达情况 ,同时监测糖尿病小鼠血糖、体重等指标的变化。结果 糖尿病小鼠的血糖在注射pcDNA3 mhINS一天内迅速下降至正常 ,并在此后的三天内逐渐上升到原来的高血糖水平 ,第二次注射后出现相同的情况。注射林格液的糖尿病对照组则始终处于高血糖水平。结论 含有人胰岛素原突变基因的裸质粒成功转染糖尿病小鼠 ,并有显著的短期降血糖效应。

Objective To study the expression and therapeutical effect of naked plasmid with mutant human proinsulin gene (mhINS) in streptozotocin-induced diabetic mice. Methods Firstly, insulin expression of pcDNA3-mhINS in L02 cells was monitored by radioimmunoassay. Secondly, naked plasmid DNA was delivered into diabetic mice by tail vein injection using a hydrodynamics-based procedure, then tissue distribution and expression of pcDNA3-mhINS were determined by PCR and RT-PCR. At the same time, blood glucose, body weight and other data were observed. Results Blood glucose of diabetic mice was reduced to normal level rapidly on the first day after the injection of plasmid pcDNA3-mhINS, then rose to hyperglycemic level gradually within three days. The mode of changes in blood glucose level was almost identical after the second injection of plasmid pcDNA3-mhINS. Diabetic control mice injected with Ringer′s saline maintained hyperglycemia during the whole experiment. Conclusion Naked plasmid with mutant human proinsulin gene is successfully transfected into diabetic mice, which show the singificant short-term effect of decreasing blood glucose.