Fig. 4.

Effects of the Ex-4 on insulin secretion. Human islet was pretreated with H89 (10 µM). After 30 min, HIT-T15 cells or human islet was treated Ex-4 (25 nM) and NAC (5 mM) for 1 hr before stress induction. After treatment of H₂O₂ (100 µM, 2 hr), (A) Expression levels of insulin2 mRNA were examined by real time RT-PCR in HIT-T15 cells. Data were expressed as the rates to the expression levels to GAPDH in the same sample. GAPDH used for loading control. (B) Insulin secretion in human islet was detected by Insulin ELISA kit. Data are shown as the means±S.E. of four independent experiments.

^*P<0.01 vs H₂O₂ alone; ^†P<0.01 vs Ex-4 in treated H₂O₂.