高浓度葡萄糖条件下罗格列酮对NIT-1细胞增殖、胰岛素分泌水平及IRS-2表达的影响

Effects of rosiglitazone on proliferation of NIT-1 cells,secretion level of insulin and expression of IRS-2 under condition of high concentration glucose

目的探讨高浓度葡萄糖条件下罗格列酮对胰岛β细胞增殖、胰岛素分泌功能的影响及机制。方法取对数生长期NOD鼠胰岛β细胞株NIT-1,以胰酶消化离心、收集细胞,按5×104个细胞/孔移至24孔培养板,继续培养48 h后分别用葡萄糖浓度为5.6～27.6 mmol/L的RPMI1640培养基处理,24 h后随机分为对照组、罗格列酮1～3组,分别加入浓度为0～10-5mol/L的罗格列酮培养;分别于干预24 h和48 h时收集细胞培养上清液,采用MTT法检测各组细胞增殖活性,放射免疫法检测胰岛素水平;Western blot技术检测胰岛素受体底物(IRS)-2蛋白表达水平。结果①四组细胞增殖活性及胰岛素分泌水平均随葡萄糖浓度升高而降低,其中罗格列酮1～3组细胞增殖活性和胰岛素分泌量均显著高于对照组(P<0.050、.01)。②罗格列酮3组在葡萄糖浓度为22.5、27.6 mmol/L培养24 h及葡萄糖浓度为11.1 mmol/L培养48 h时胰岛素分泌水平均显著高于对照组(P<0.050、.01);不同浓度葡萄糖培养下罗格列酮3组细胞中IRS-2蛋白水平均显著高于对照组(P<0.05、0.01),且变化趋势同上。结论在高浓度葡萄糖条件下罗格列酮可促进NIT-1细胞增殖、胰岛素分泌,机制可能与其上调IRS2表达有关。

Objective To investigate the effects of rosiglitazone on cell proliferation of pancreatic 13 cells and insulin secretory function, under condition of high concentration glucose. Methods The pancreatic β cells NIT-1 in logarithmic phase were digested and centrifuged, then were put into plates （5 × 10^4 cells/well） and cultivated for 48 h and treated with different concentrations of glucose at 5.6-27.6 mmol/L. After cultivated for 24 hs, all the cell were divided randomly into control group and rosiglitazone 1-3 groups, and were interfered with rosiglitazone of 0-10^-5 mol/L, then the supernatant was collected aftert 24 and 48 hs, the cell proliferation were measured by MTT techniques. Insulin level was evaluated by radioimmunity assay. The expression levels of IRS-2 protein were detected by Western blot respectively. Results （1）Cell proliferation and insulin secretion of the four groups decreased as glucose levels elevated, the cell proliferation and insulin secretion of rosiglitazone 1-3 groups were significantly higher than those of the control group （ P 〈 0.05,0.01 ）. （2）The insulin secretion levels in rosiglitazone 3 group were significantly higher than those in the control group, under the condition of 22.5, 27.6 mmol/L glucose for 24 hs and 11.1 mmol/L for 48 hs （P 〈 0.05, 0.01 ） ; under the condition of different glucose concentration, the expression of IRS-2 protein in rosiglitazone 3 group were higher than those in control group （P 〈 0.05, 0.01 ）, and it varied with glucose concentration change trend of the same as above, Conclusion Under high glucose concentration condition, rosiglitazone can improve the secretion function and cell proliferation of pancreatic 13 cells, the mechanism maybe related to the up-regulation of IRS-2 expression.