Study On The Mechanism Of Metabolic Mem Ory Of Hyperglycemia On Injury Of Endothe Lial Cells

Objective: to study the role and significance of transient High glucose on human vascular endothelial cells.Methods: Cultured primary human umbilical vein endothelial cells were used to study.HUVECs were divided into 4 group:1.Normal control group(NG,5.5mM D-glucose for 7 days),2.Persistent high glucose group(HG,30mM D-glucose for 7 days),3.Transient high glucose group(TG,30mM D-glucose for 1 day then 5.5mM D-glucose for 6 days),4.mannitol control group(MA,5.5mM D-glucose and 24.5mM D-mannitol for 7 days).We measured cell proliferation(MTT method),cell apoptosis(annexin V—FITC/PI double staining),ROS generation(DCFH-DA staining),SOD level(wst-1 method),MDA level(TBA method),NO level(Griess method),eNOS mRNA(real-time PCR) and protein level(western blot).Results: Cell proliferation is inhibited in HG group and TG group relative to NG group and also inhibited in MA group. High glucose can induce apoptosis of endothelial cells,incease ROS and MDA generation and down-regulate intracellular SOD level ,which can still maintain after re-establishing good blood glucose control. eNOS expression and NO generation of high glucose treated HUVEC persistent lower than NG group after a pe-riod of increasing when measured after the first 24h.Conclusion: Transient high glucose can inhibit endothelial cells proliferation and increase cell apoptosis,induce oxidative stress and reduce endothelium-dependent vasodilatation which can still persisitent even after re-establishment of good blood glucose control.