The Effect Of 11β-hsd1 In High Glucose-cultured Pig Iliac Endothelium Cell Lines

Objective To investigate the effect of high glucose on the activity of 11β-HSD1and the influence of the inhibitor of 11β-HSD1 on the expression of P-P38MAPK and P-ERK1/2. and cell survival in pig iliac artery endothelial cells cultured in high glucose condition. Methods ( 1 )Cultured the PIECs in vitro, when the cells reached near 80% confluency, the FBS was deprived for over night to arrest and synchronize cell growth, thereafter the cells were treated with D-glucose at different concentrations (ranging from 5.6 to 33 mmol/L ) for 24h with or without enzymic substrate and cooperator NADPH, or enzyme inhibitor glycyrrhetic acid. The transformation efficiency of cortison was measured by HPLC as standard to evaluate activity of 11β-HSD1. MTT and FACS-FCM PI were performed to analyze the viability and apoptpsis of PIECs. (2)The cultur of PIECs were same as above, then the cells were treated with high glucose at different concentrations (ranging from 5.6 to 33mmol/L ) for 48h or exposed to 33mmol/L D-glucose for 0,12 or 24,48,72 h, respectively. Otherwise the cells were exposed to medium containing 5.5Mm D-glucose(control), 33mM D-glucose (high) in the presence or absence of 10-5M GA. Western blot analysis was used to determine the activation of p38MAPK and ERK. The trypan-blue exclusion test was used to study the influence of GA on cell survial. Results (1)the activity of 11β-HSD1 increased in the higher D-glucose with enzymic substrate and NADPH and presented positive dependablity. The endothlial cell viability decreased and the number of apoptosis rose.( 2 ) PIECs show increased P-P38MAPK and P-ERK1/2 activity after exposure to high glucose, the expression of p-P38MAPK was positive correlation with the time and the concentration of D-glucose; However the P-ERK had its expression peak at 24h. The GA can reduce the expression of the P-P38MAPK partly and it could make the cell survival increase. Conclusion the increased activity of 11β-HSD1 caused by higher D-glucose concentration may damage endothlial cell function due to amplifying the local effect of glucocorticoeds. The inhibitor of 11β-HSD1 can reduce the expression of the p-p38MAPK partly in PIECs culture in high glucose condition ,making the cell death of endothelial cells decrease. The indicated that 11β-HSD1 could effects the vascular endothelial cell via MAPKs signal pathway.