Thapsigargin and high glucose and palmitic acid potentiate ER stress gene expression in hIAPP-INS1E cells.

ER stress expression markers CHOP, ATF3 and sXBP1 were determined by real-time PCR from hIAPP-INS1E, rIAPP-INS1E and INS1E control cells cultured at A) 11 mM glucose B) 11 mM glucose exposed to 0.5 µM of thapsigargin for 8 hours or C) 25 mM of glucose (HG) with 400 µM palmitic acid (PA) for 24 hours. Results are normalized to untreated INS1E, rIAPP-INS1E or hIAPP-INS1E cells (dashed line) and expressed as mean ± S.E.M from five independent experiments. *p<0.05 **p<0.01 and ***p<0.001 vs. rIAPP and ^##p<0.01, ^###p<0.001 vs. INS1E control. n.s., not significant.