·糖尿病基础研究·

　　【摘要】 目的 探讨细胞内基质金属蛋白酶2(MMP-2)基因过表达对大鼠胰岛β细胞株INS-1细胞功能的影响。 方法 采用基因重组技术将大鼠MMP-2 cDNA插入真核表达载体pcDNA 3.1( +)构建大鼠MMP-2真核表达质粒，培养INS-1细胞。随机分为正常对照组，空质粒转染组及MMP-2转染组。脂质体Lipofectmine 2000转染INS-1细胞，观察INS-1细胞内MMP-2基因和蛋白表达量变化，MMP-2酶活性变化,以及INS-1细胞凋亡情况与胰岛素分泌功能的变化。 结果 与正常对照组、空质粒组比较，MMP-2转染组MMP-2 mRNA表达增加(P均<0.05)，蛋白表达水平和酶活性上调(P均<0.05);MMP-2转染组细胞凋亡率(56.07±3.68)%，高于正常组(33.70±6.53)%及空质粒转染组(38.02±5.60)%(P<0.05)。而其胰岛素释放指数为(1.30±0.27)，低于正常组(3.37±0.76)与空质粒组(2.90±0.84)(P<0.05)。 结论 细胞内MMP-2基因的过表达可引起胰岛β细胞凋亡增加，胰岛素分泌功能下降。

　　【关键词】 基质金属蛋白酶2;INS-1;氧化应激;糖尿病，2型

Effect of overexpressed intracellular matrix metalloproteinase 2 on INS-1 cell function LIU Chong-xiao, WAN Xiao-yu, CHEN Yuan-wen, et al. Department of Endocrinology, Xinhua Hospital，Shanghai Jiaotong University School of Medicine, Shanghai 200092, China

Corresponding author：DONG Yan，E-mail：yandong00@hotmail.com

　　【Abstract】 Objective To assess the effect of an overexpressed intracellular matrix metalloproteinase 2(MMP-2)on the INS-1 cells function. Method Rat MMP-2 cDNA was cloned into eukaryotic plasmid pcDNA3.1(+)to construct MMP-2/ pcDNA3.1(+)plasmid. The cultured INS-1 cells were randomized to three groups：the control group, empty vector transfected group and MMP-2 transfected group， and then transfected by Lipofectmine 2000 to determine the expression of intracellular MMP-2 and the gelatinase activity of MMP-2. Apoptosis and insulin-secretion function in INS-1 cells after transfection was assessed as well. Results Higher expression of MMP-2 mRNA and protein, coming with up-regulation of its enzyme activities were found in MMP-2 transfected group , as compared to the control and vector transfected groups(P<0.05). The apoptosis rate was higher in MMP-2 transfected group[(56.07±3.68)% ]than in control group and empty vector transfected group[(33.70±6.53)% and (38.02±5.60)% respectively, P<0.05]. However the insulin release index of MMP-2 in transfected group was only(1.30±0.27), which was much lower as compared to control group(3.37±0.76) and empty vector transfected group(2.90±0.84)(P<0.05). Conclusion The overexpression of intracellular MMP-2 may be related with an induced INS-1 cells apoptosis and with decreased pancreatic β cells function.

　　【Key words】 Matrix metalloproteinase 2; Oxidative stress; Diabetes mellitus,type 2;INS-1;