Kv1.5蛋白通道阻滞剂DPO-1对LPS诱导的大鼠主动脉内皮细胞损伤的影响

Effects of Kv1.5 specific channel blocker DPO-1 on LPS induced endothelial cell injury in rats

目的:研究Kv1.5蛋白通道阻滞剂DPO-1对LPS诱导的大鼠主动脉内皮细胞损伤的影响。方法:将大鼠随机分为Control组、LPS组、LPS+DPO-11组、LPS+DPO-12组,LPS组静脉注射5 mg/kg LPS建立脓毒症模型,LPS+DPO-11组、LPS+DPO-12组建模后分别腹腔注射不同剂量DPO-1(0.3、3 mg/kg)。取大鼠胸主动脉,分离内膜组织,Western blot检测内皮细胞中Kv1.5蛋白水平,流式细胞仪检测内皮细胞凋亡率;ELISA检测各组大鼠血清内皮细胞标志物内皮细胞特异性分子-1(Endocan)、内皮细胞黏附分子-1(VCAM-1)、血管性血友病因子(vWF)及血清炎症因子IL-6、IL-1β及TNF-α水平,并测定超氧化物歧化酶(SOD)、丙二醛(MDA)和髓过氧化物酶(MPO)含量。结果:Kv1.5蛋白在Control组及LPS组存在表达,与Control组相比,LPS组Kv1.5蛋白表达增加(P<0.01);流式细胞结果显示,LPS组内皮细胞凋亡率较Control组明显上升(P<0.01),而LPS+DPO-11组及LPS+DPO-12组内皮细胞凋亡率较LPS组下降(P<0.05);与Control组相比,LPS组血清内皮细胞标志物Endocan、VCAM-1、vWF及血清炎症因子IL-6、IL-1β及TNF-α水平明显升高(P<0.05),给予Kv1.5特异性通道阻滞剂DPO-1干预后,大鼠血清内皮细胞标志物Endocan、VCAM-1、vWF及血清炎症因子IL-6、IL-1β及TNF-α水平下降(P<0.05),且这一效应随DPO-1剂量增加而加强;LPS组较Control组MDA、MPO水平上升,SOD活性降低(P<0.05),而DPO-1预处理可降低MDA、MPO含量、增加SOD活性(P<0.05)。结论:Kv1.5蛋白通道DPO-1通过阻断Kv1.5通道,减轻主动脉内皮细胞脂质过氧化损伤,抑制炎症反应。

Objective:To study the effect of Kv1.5 specific channel blocker DPO-1 on the injury of rat aortic endothelial cells induced by LPS.Methods:Rats were randomly divided into Control group,LPS group,LPS+DPO-11 group and LPS+DPO-12 group.Rats in LPS group was intravenous injection of 5 mg/kg LPS,LPS+DPO-11 group and LPS+DPO-12 group were intravenous injection of different doses of DPO-1(0.3、3 mg/kg).The rat thoracic aorta was taken,the intimal tissue was separated,the Kv1.5 protein level in endothelial cells was detected by Western blot,and the apoptosis rate of endothelial cells was detected by flow cytometry;ELISA was used to detect the levels of serum endothelial cell markers Endocan,vascular cell adhesion molecule-1(VCAM-1),von Willebrand factor(vWF)and serum inflammatory factors IL-6,IL-1βand TNF-αlevels.The contents of superoxide dismutase(SOD),malondialdehyde(MDA)and myeloperoxidase(MPO)were determined.Results:Kv1.5 protein was expressed in the Control group and the LPS group.Compared with Control group,the Kv1.5 protein expression in the LPS group was increased(P<0.01);Flow cytometry results showed that the endothelial cell apoptosis rate in the LPS group was significantly increased(P<0.01),while the endothelial cell apoptosis rates in the LPS+DPO-11 group and LPS+DPO-12 group were respectively lower than the LPS group(P<0.05);compared with the control group,Endocan,VCAM-1,vWF,IL-6,IL-1β,TNF-αlevels in the LPS group were significantly increased(P<0.05).After the intervention of the Kv1.5 specific channel blocker DPO-1,the levels of Endocan,VCAM-1,vWF,IL-6,IL-1β,TNF-αwere decreased(P<0.05),and this effect was increased with the increase of DPO-1 dose;compared with blank control group,the levels of MDA and MPO in the LPS group were increased,and SOD activity was decreased(P<0.05),while DPO-1 pretreatment could reduced the content of MDA and MPO,and increased SOD activity(P<0.05).Conclusion:Kv1.5 specific channel blocker DPO-1reduces the lipid peroxidation damage of aortic endothelial cells and inhibits inflammation by blocking the Kv1.5 channel.