Abstract:

Objective To investigate the effects of high glucose on the apoptosis of human umbilical vein endothelial cells (HUVECs) and its correlation with Caspase-3 expression. Methods HUVECs were cultured by glucose solution of different concentrations for 48 h. The apoptosis of cells was observed by the TUNEL staining. The survival, apoptosis, and necrosis of cells were detected by the flow cytometry (Annexin V-FITC and PI dual fluorescence). The expression of cleaved Caspase-3 of cells was observed by the Western Blot analysis. Results The apoptotic cells of the high glucose group (33 mmol/L) were significantly more than those of the normal glucose group (5.5 mmol/L) under the optic microscope. The TUNEL-positive nuclei of the high glucose group were more than those of the normal glucose group in 3 randomly selected fields. The results of flow cytometry showed that for the normal glucose group; the apoptosis rate was (4.10±2.16)%, the necrosis rate was (0.47±0.05)%; and the survival rate was (94.44±2.13)%. While for the high glucose group, the apoptosis rate was (16.13±1.51)%; the necrosis rate was (1.09±0.27)%; and the survival rate was (81.99±1.13)%. The difference of apoptosis rate of two groups was statistically significant (P<0.05). The results of Western blotting method showed that the Caspase-3/β-actin levels of the normal glucose group and high glucose group were 0.062±0.005 and 0.125±0.05, respectively. The difference was statistically significant (P<0.05).  The expression of cleaved Caspase-3 of the high glucose group increased. Conclusion The apoptosis of HUVECs under high glucose increases, which may be relevant to the increase of expression of cleaved Caspase-3.

Key words: high glucose, human umbilical vein endothelial cell, apoptosis, Caspase-3