Effects of Kv1.5 Protein on LPS-induced Oxidative Stress Injury in Endothelial Cells
Xu Meixia;Zou Lijuan;Zhang Xiaoxia;Intensive Care Unit,Wuhan Fourth Hospital,Puai Hospital,Tongji Medical College,Huazhong University of Science and Technology;
Objective To investigate effects of Kv1.5 protein on LPS-induced peroxidation injury in endothelial cells.Methods Human umbilical vein endothelial cells(HUVECs)were cultured in vitro.Sepsis model was established by stimulating HUVECs with LPS(5μ/mL).The experiment was divided into four groups:Control group,LPS group,LPS+ MT1 group(250 nmol/L of MT was used for pretreatment for 30 min to block Kv1.5 channels)and LPS+MT2(500 nmol/L MT).Then the survival rate of endothelial cells was detected by MTT assay.ELISA was used to detect the changes of E-selectin and ICAM-1 in the supernatant,and to measure MDA and SOD activity.Results Compared with the control group,the survival rate of endothelial cells in LPS group was significantly decreased[(32.54±1.87)%vs.(98.64±0.92)%,P0.01],while the survival rate of LPS+MT1 group and LPS+ MT2 group was(77.39±1.15)% and(93.22±1.15)%,which was significantly higher than that of LPS group(P0.01).At the same time,the secretion of E-selectin and ICAM-1 in endothelial cells of LPS group increased(P0.01),and decreased after pretreatment with 250 and 500 nmol/L MT(P0.01).By observation with laser confocal microscopy,intracellular ROS level in endothelial cells in LPS group were increased to(3.39±0.42)times as much as that of the blank control group(P0.05),and after pretreatment with 250 and 500 nmol/L MT,ROS level was(1.88±0.36)times and(1.46±0.47)times as much as that of the blank control group,respectively,which was significantly different from that of LPS group(P0.05).Compared with the blank control group,MDA level was significantly increased and SOD activity decreased in LPS group(P0.01),while MT pretreatment significantly reduced MDA content and increased SOD activity(P0.01).Conclusion Kv1.5 protein is closely related to LPS-induced injury of vascular endothelial cells.MT can reduce lipid peroxidation injury of endothelial cells by blocking Kv1.5 channel.
【Fund】： 武汉市卫生计生委科研基金资助项目(No.wx14c64);; 湖北省自然科学基金资助项目(No.ZRY2014001335)
【CateGory Index】： R363
【CateGory Index】： R363