腺病毒介导鼠胰岛素样生长因子1基因对胰岛β细胞的保护作用

Protective effect of adenovirus vector mediated rat insulin-like growth factor 1 gene on pancreatic beta cells

背景:研究表明自身高表达胰岛素样生长因子1的小鼠对药物诱导糖尿病有一定的预防作用。目的:观察腺病毒介导鼠胰岛素样生长因子1基因对胰岛β细胞损伤的保护作用。方法:①体外实验:以Ad-rIGF-1、Ad-eGFP直接感染鼠胰岛β细胞标准细胞株-R1Nm5F细胞,然后两组再分别加入0,1.5mmol/L链脲佐菌素。②体内预防实验:将60只昆明小鼠随机分为空白对照组(不做任何处理)、糖尿病对照组(制作糖尿病模型)、空载体对照组(仅腹腔注射Ad-eGFP重组腺病毒液)、Ad-rIGF-1组(于糖尿病模型制作前2周腹腔注射Ad-rIGF-1重组腺病毒液)。③体内治疗实验:将75只昆明小鼠随机分组:空白对照组(不做任何处理)、糖尿病对照组、胰岛素组、Ad-rIGF-1组、Ad-rIGF-1联合胰岛素组。后3组制作糖尿病模型后给予相应干预。结果与结论:①鼠胰岛素样生长因子1在胰岛β细胞有效表达,并具有抑制链脲佐菌素诱导胰岛β细胞凋亡的作用。②Ad-rIGF-1组糖尿病发病率低,平均血糖水平低,胰腺炎症浸润程度轻。③与糖尿病对照组、胰岛素组相比,Ad-rIGF-1组和Ad-rIGF-1联合胰岛素组胰腺炎症浸润程度轻,鼠胰岛素样生长因子1在胰岛局部高表达;胰岛素组、Ad-rIGF-1组、Ad-rIGF-1联合胰岛素组血清C-肽水平低,组间比较无明显差别(P>0.05)。表明胰岛β细胞局部表达鼠胰岛素样生长因子1能够保护胰岛β细胞功能,提高细胞存活率,预防和减轻链脲佐菌素诱导的昆明小鼠1型糖尿病。但鼠胰岛素样生长因子1基因转导与胰岛素皮下注射联合应用对糖尿病早期残存胰岛细胞功能的保护效果不明显。

BACKGROUND：Research shows that the high expression of the rat insulin-like growth factor 1（rIGF-1） has certain preventive effect on drug induced diabetes.OBJECTIVE：To investigate the protective effect of adenovirus vector mediated rat rIGF-1 gene on pancreatic β-cells impairment.METHODS：①In vitro experiment：the RINm5F cells of pancreatic β-cells were infected with Ad-rIGF-1 and Ad-eGFP gene,each group was treated with 0 or 1.5 mmol/L streptozotocin（STZ） medium.②In vivo prevention experiment：60 Kunming mice were randomly divided into four groups：blank control group（without any treatment）,diabetes mellitus group（diabetes mellitus model was established）,Ad-eGFP group（treated with intraperitoneal injection of Ad-eGFP adenovirus medium） and Ad-rIGF-1 group（treated with intraperitoneal injection of Ad-rIGF-1 adenovirus medium at two weeks early before the establishment of diabetes mellitus model）.③In vivo treatment experiment：75 Kunming mice were randomly divided into five groups：blank control group（without any treatment）,diabetes mellitus group,insulin group,Ad-rIGF-1 group and Ad-rIGF-1 plus insulin group.Corresponding intervention was given to the last three groups before the establishment of diabetes mellitus model.RESULTS AND CONCLUSION：①The rIGF-1 was expressed in pancreatic β-cells and could inhibit the apoptosis of STZ induced pancreatic β-cells.②Prevention experiment showed that the Ad-rIGF-1 group had a lower incidence in diabetes and a lower degree of average blood glucose and the inflammatory infiltration was lighter.③Compared with diabetes mellitus group and insulin group,the inflammatory infiltration was lighter in Ad-rIGF-1 group and Ad-rIGF-1plus insulin group and the rIGF-1 was highly expressed in part of the islet cells;serum C peptide detected by enzyme linked immunosorbent assay showed a lower degree in insulin group,Ad-rIGF-1 group and Ad-rIGF-1 plus insulin group,however it had no difference between groups（P 0.05）.These results suggested that locally produced rIGF-1 in pancreatic β-cells could maintain the β cells function,promote islet survival rate and prevent and mitigate the STZ-induced type 1 diabetes mellitus.The effect of rIGF-1 transduction combined with insulin subcutaneous injection on the protection of the function of residual islet cells in early diabetes models was not obvious.