High glucose changes the expression of GRP78 in COX-2 dependent manner in HUVECs

AIM:To investigate the effect of high glucose on the expression of an endoplasmic reticulum stress marker glucose-regulated protein 78(GRP78),and explore its underlying mechanism.METHODS:(1) Human umbilical vein endothelial cells(HUVECs) were exposed to normal glucose(5.5 mmol/L) and high glucose(30 mmol/L) for 24 h,36 h or 48 h.Cell viability was determined by MTT method.Cell apoptosis was detected by flow cytometry analysis.The expression of proteins was evaluated by Western blotting analysis.RESULTS:After treated with high glucose for 24-48 h,the expression of GRP78 increased early but decreased at 48 h of incubation,while cyclooxygenase-2(COX-2) expression increased in a time-dependent manner.COX-2 selective inhibitor nimesulide inhibited high glucose induced changes of GRP78 expression and also inhibited high glucose induced cell apoptosis.CONCLUSION:Prolonged high glucose exposure changes the expression of GRP78 in a COX-2 dependent manner in HUVECs.