Endoplasmic Reticulum Stress Was Enhanced Due To Fluctuated Glucose In Human Umbilical Vein Endothelial Cells

Aim:To explore the effects of the different glucose concentration and the intermittent glucose on endoplasmic reticulum stress in human umbilical endothelial cells and the protective effect of resveratrol on human umbilical vein endothelial cells oxidative damage results from glucose.Methods:Human umbilical vein endothelial cells(HUVEC)were randomly divided into six groups:Normal glucose group(NG,with 5.6mmol/L glucose),low glucose group(LG,with 2.8mmol/L glucose),high glucose group(HG,with 30mmol/L glucose),30mmol/L glucose alternating with 5.6mmol/L glucose group (HNF,with 30mmol/L glucose and 5.6mmol/L glucose),30mmol/L glucose alternating with 2.8mmol/L glucose group(HLF,with 30mmol/L glucose and 2.8mmol/L glucose),RES group(HLF+RES,RES with 10^-4mol/L).HNF,HLF, HLF+RES groups were alternated 30mmol/L glucose with 5.6mmol/L glucose or 2.8mmol/L glucose per 24h respectively for 48h.The glucose regulated protein78 (GRP78),growth arrest and DNA damage inducible gene 153(CHOP/GADD153) mRNA were detected with reverse transcription polymerase chain reaction(RT-PCR) in NG,LG,HG groups at 12,24 and 48h.The mRNA and protein expressions of GRP78,CHOP/GADD153 were detected with reverse transcription polymerase chain reaction(RT-PCR)and Western blot in each group at 48h.The apoptosis and proliferation were measured by Hoechst33258 and MTT in each group at 48h,and the levels of TAC,MDA,SOD were measured and analysed.Results:1 The results showed that the GRP78 mRNA expression increased at 12h but reduced gradually at 24 and 48h in HG and LG groups compared with NG group.However,CHOP/GADD153 mRNA expression increased gradually at 12,24 and 48h.Comparing with NG group,GRP78 mRNA expression were lower in all treated groups at 48h(P＜0.01),HLF group showed the lowest GRP78 mRNA level (P＜0.01).Meanwhile,all treated groups showed increased CHOP/GADD153 mRNA expression compared with NG group(P＜0.01).At protein levels,all treated groups showed increased CHOP/GADD153 and GRP78 expressions compared with NG group(P＜0.01).However,HLF+RES group showed the more decreased GRP78, CHOP/GADD153 protein expression than HLF group(P＜0.01).2 The cell proliferation of each groups was significantly inhibited compared with NG group at 48h(P＜0.01),and the apoptosis cells significantly increased in all treated groups compared with NG group detected by Hoechst33258.3 LG,HG,HNF and HLF groups Showed the decreased TAC and SOD and the increased MDA compared with NG group,and HLF+RES group has obvious effects on the above parameters.Conclusion:High glucose,low glucose and fluctuate glucose all induce endoplasmic reticulum stress and result in oxidation and antioxidant system imbalances in vascular endothelial cells.Fluctuate glucose has the more serious effect on vascular endothelial cells than low or high glucose.Resveratrol treatment could significantly relieve endoplasmic reticulum stress in vascular endothelial cells, and has a protective effect on the balance between oxidation and antioxidant system...