转基因小鼠胰岛β细胞株胰岛素样生长因子1受体和胰岛素受体表达与小檗碱的干预效应

Effects of berberine on the expressions of insulin receptor and insulin-like growth factor-1 receptor mRNA in islet beta cell strain of transgenic mice

目的:观察小檗碱对转基因小鼠胰岛β细胞株胰岛素受体和胰岛素样生长因子1受体mRNA表达的影响。方法:实验于2005-09/2006-10在华中科技大学同济医学院附属同济医院中西医结合研究所完成。①实验材料:培养NIT-1细胞,在低糖(5.5mmol/L)和高糖(11.1mmol/L)环境下,分别加入0,1,3,10,30μmol/L的小檗碱和1μmol/L的格列苯脲,0μmol/L小檗碱组为空白对照组。②实验评估:培养24h后,采用四甲基偶氮唑盐法检测小檗碱NIT-1细胞增殖抑制作用;逆转录-聚合酶链反应测定NIT-1细胞胰岛素受体和胰岛素样生长因子1受体mRNA表达。结果:①四甲基偶氮唑盐法检测发现,不同浓度小檗碱(1～30μmol/L)与NIT-1细胞作用24h后,小檗碱组吸光度值比空白对照组低,随着小檗碱浓度的增加,吸光度值逐渐从0.356±0.061降低至0.162±0.014,而且在各组之间有显著性差异。②在低糖及高糖环境下,与空白对照组相比,小檗碱能促进NIT-1细胞胰岛素受体mRNA的表达(低糖环境:0.27±0.04,0.49±0.02;高糖环境:0.22±0.04,0.42±0.03;P<0.01),但仍低于格列苯脲组(低糖环境:0.75±0.22;高糖环境:0.78±0.01;P<0.01);而且随着小檗碱浓度的升高,NIT-1细胞胰岛素受体mRNA表达的增加更为明显,分别从0.49±0.02增高至0.68±0.44及从0.42±0.03增高至0.71±0.01。与空白对照组相比,小檗碱组胰岛素样生长因子1受体mRNA的表达无明显改变。结论:小檗碱促进胰岛素分泌,其作用机制可能与促进胰岛β细胞胰岛素受体mRNA表达有关。

AIM： To observe the effects of berberine on the expression of insulin receptor （InsR） and insulin-like growth factor-1 receptor （IGF-1R） mRNA in islet β cells of transgenic mice. METHODS： The experiment was carried out in the Institute of Integrative Traditional Chinese ＆ Western Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from September 2005 to October 2006. ①NIT-1 cells were cultured under low glucose （5.5 mmol/L） and high glucose （11.1 mmol/L） condition in medium containing 0, 1, 3, 10, and 30 μmol/L berberine and 1 mmol/L glibenclamide; meanwhile, cells cultured in medium with no berberine served as controls. ②After cultured for 24 hours, the proliferation ability of cells was determined by MTT; the expressions of InsR and IGF-1R mRNA in NIT-1 cells were detected by RT-PCR. RESULTS： ①MTT results showed that the A value of berberine groups was lower than that in control group 24 hours after co-culture of berberine （1-30 μmol/L） and NIT-1 cells, and with the increase of berberine, the values of the cells were decreased from 0.356±0.061 to 0.162±0.014. There were significant differences between any two groups. ②Both in low and high glucose culture medium, compared with that in control group, the expressions of InsR mRNA was increased in berberine-treated groups （low glucose： 0.27±0.04,0.49±0.02; high glucose： 0.22±0.04,0.42±0.03; P 〈 0.01 ）, but was still lower than that in glibenclamide group （low glucose： 0.75±0.22; high glucose： 0.78±0.01, P 〈 0.01）. Moreover, with the increase of berberine concentration, the expressions of InsR mRNA became more abundant in the berberine treated NIT-1 cells from 0.49±0.02 to 0.68±0.44 and from 0.42±0.03 to 0.71±0.01. On the contrast, the expressions of IGF-1R mRNA was not significantly changed after incubation with berbenne compared with control group. CONCLUSION： Berbedne promotes insulin secretion through increasing the expressions of InsR mRNA in islet β cells.