Abstract:

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.

Key words: dehydroepiandrosterone sulfate, pancreatic B cells, insulin secretion