硫酸脱氢表雄酮刺激MIN6细胞胰岛素分泌的机制研究

目的 初步探讨硫酸脱氢表雄酮(DHEAS)促进MIN6细胞胰岛素分泌的机制.方法 选用小鼠胰岛B细胞株MIN6作为实验对象,在葡萄糖浓度为2.8 mmol/L和16.7 mmol/L的条件下,分别以0.1、1、5、10、50μmol/L的DHEAS干预10 min和24h,采用ELISA法测定细胞培养上清液中胰岛素的含量,应用相关试剂盒检测细胞内三磷酸腺苷(ATP)和二磷酸腺苷(ADP)的生物发光水平及比率(ATP/ADP)；采用Real-Time PCR法检测不同浓度DHEAS干预24 h的细胞内葡萄糖激酶(GCK) mRNA的表达.结果 两种葡萄糖浓度条件下,以5、10、50 μmol/L DHEAS干预10 min和24 h的MIN6的细胞培养上清液中胰岛素含量和细胞内ATP/ADP比率显著高于空白对照组(P＜0.05).与空白对照组比较,1、5、10、50 μmol/L DHEAS干预24 h的MIN6细胞内GCK mRNA表达显著上调(p＜0.05).结论 DHEAS可能通过增加ATP/ADP的比率,促进MIN6细胞胰岛素的分泌；干预24 h的效应可能与上调GCK mRNA的表达、促进葡萄糖酵解有关.

Mechanism of dehydroepiandrosterone sulfate in stimulation of insulin secretion in MIN6 cells

Objective To investigate the mechanism of dehydroepiandrosterone sulfate(DHEAS) in stimulation of insulin secretion in MIN6 cells.Methods Mouse pancreatic B cell line MIN6 was selected,and MIN6 cells were treated with 0.1,1,5,10 and 50 μmol/L DHEAS for 10 min and 24 h respectively under the conditions of 2.8 mmol/L and 16.7 mmol/L blood glucose.The insulin contents in the supernatant of culture fluid were determined by ELISA,the levels of adenosine triphosphate(ATP) and adenosine diphosphate(ADP) in cells were measured by relative reagent kits,ATP/ADP in cells was calculated,and the expression of glucokinase(GCK) mRNA in cells treated by different concentrations of DHEAS for 24 h was detected by Real-Time PCR.Results Under the conditions of two concentrations of blood glucose,the insulin contents in the supernatant of culture fluid and ATP/ADP in cells treated by 5 μmol/L,10 μmol/L and 50 μmol/L DHEAS for 10 min and 24 h were significantly higher than those in blank controls(P<0.05).Compared with blank controls,the expression of GCK mRNA in MIN6 cells treated by 1 μmol/L,5 μmol/L,10 μmol/L and 50 μmol/L DHEAS for 24 h was significantly higher(P<0.05).Conclusion DHEAS may stimulate insulin secretion in MIN6 cells through increase of ATP/ADP.After treatment by DHEAS for 24 h,the stimulation of insulin secretion may be associated with the up-regulation of GCK mRNA expression and glycolysis.