脂多糖预处理对VEGF165、Ang-1与HMGBx1在缺血-再灌注损伤心肌中表达的影响

Effects of LPS preconditioning on expressions of VEGF165,Ang-1 and HMGBx1 in myocardium underwent ischemia-reperfusion injury

目的探讨脂多糖预处理对血管内皮生长因子(VEGF165)、促血管生成素1(Ang-1)与高迁移率族蛋白B1(HMGBx1)在缺血-再灌注损伤心肌中表达的影响。方法普通B6小鼠制作心肌缺血-再灌注动物模型,实验组手术前给予脂多糖。用TUNEL检测心肌细胞凋亡状况,用凝胶迁移率实验(EMSA)检测核转录因子(NF-κB)的活力,用Western blot检测VEGF165、Ang-1、HMGBx1在心肌中的表达。大鼠心肌成肌细胞H9c2,转染携带人VEGF165和Ang-1的腺病毒,随后过氧化氢刺激,检测HMGBx1的胞浆含量和NF-κB的活性。结果小剂量脂多糖预处理能显著促进VEGF165、Ang-1在缺血-再灌注损伤心肌中的早期表达,并同时显著减少HMGBx1的表达和抑制心肌细胞凋亡。细胞实验提示VEGF165和Ang-1联合使用能显著减少心肌细胞胞浆中HMGBx1的含量和NF-κB的活性。结论 VEGF165和Ang-1可能通过抑制NF-κB的活性,减少HMGBx1的含量而对心肌细胞产生直接保护作用。

Objective To investigate the effects of LPS preconditioning on the expressions of vascular endothelial growth factor 165（VEGF165）,angiopoietin-1（Ang-1） and high mobility group box1（HMGBx1） in the myocardium underwent ischemia-reperfusion（I-R） injury induced.MethodsIn vivo experiment,mice were pretreated with LPS before ligation of the left anterior descending coronary,which was followed by I-R.HMGBx1,VEGF165 and Ang-1 were assessed by immunoblotting.In situ cardiac,myocyte was examined by TUNEL assay.Ad-VEGF165 or/and Ad-Ang-1 or Ad-GFP was added into the medium of H9c2,and the cells were stimulated with hydrogen peroxide（H2O2） after transfection.Neuclear factor（NF-κB） activity was analyzed by electrophoretic mobility shift assay（EMSA） and HMGBx1 was assessed by immunoblotting.ResultsLPS pretreatment significantly promoted early expressions of VEGF165 and Ang-1 in the myocardium after I-R injury,reduced the expression of HMGBx1 and apoptosis of myocytes.HMGBx1 and NF-κB activities were significantly decreased by combined use of VEGF165 and Ang-1.Conclusion VEGF 165 and Ang-1 have a direct myocardial protective effects,possibly through inhibiting NF-κB activity and reducing HMGBx1.