Objective To investigate the effects of rosiglitazone on cell proliferation of pancreatic β 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 x 104 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 radio-immunity assay. The expression levels of 1RS-2 protein were detected by Western blot respectively. Results ①Cell 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). ②The 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 β cells, the mechanism maybe related to the up-regulation of IRS-2 expression.%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48h后分别用葡萄糖浓度为5.6～27.6 mmol/L的RPMI1640培养基处理,24h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24h和48h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 ＜0.05、0.01).②罗格列酮3组在葡萄糖浓度为22.5、27.6 mmol/L培养24h及葡萄糖浓度为11.1 mmol/L培养48h时胰岛素分泌水平均显著高于对照组(P＜0.05、0.01)；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.
展开▼
