四氢-β-咔啉-精氨酸-甘氨酸-天冬氨酸类肽缀合物对心脏缺血再灌注损伤的保护作用

Protective effect of phenolic tetrahydro - β - carboline - arginine - glycine - aspartic acid peptido- mimetic conjugates on cardiac ischemia -reperfusion injury

目的探讨四氢-β-咔啉-精氨酸-甘氨酸-天冬氨酸类肽缀合物（THBCB-RGD）的自由基清除和抗血栓形成特性，并通过建立心脏缺血再灌注模型，观察其在心肌缺血再灌注损伤中的作用及影响。方法使用高效液相色谱法检测THBCB—RGD的稳定性；应用PC12细胞存活实验和乙酰胆碱诱发内皮细胞介导血管舒张实验评估THBCB—RGD自南基清除能力；应用体外抗血小板聚集实验评价THBCB—RGD抗血小板聚集活性；通过体内实验评价THBCB—RGD抗血栓活性；构建心脏缺血再灌注模型，观察THBCB—RGD干预对心肌氧化应激和心肌梗死的影响。结果高效液相色谱法结果显示我们所合成的THBCB—RGD自身稳定性较高（目标峰的消失时间分别为240、180、240min，平均220min，远高于文献所报道的四氢-β-咔啉前体的30min。P=0．005）。同时它们具有很强的清除NO、H2O2和·OH的能力（与前体比较P=0．004、0．000），亦可抑制血小板的聚集和血栓的形成（血小板的聚集率和血栓湿重合血栓千重差异均达到P=0．003或P=0．000）；心脏缺血再灌注损伤前给予THBCB—RGD预处理可降低心肌中MDA含量并减少心肌梗死面积。结论THBCB—RGD表现出强的自由基清除能力和抗血栓形成活性，并可通过抑制氧化应激反应和减少心肌梗死面积，从而在心脏缺血再灌注损伤中发挥保护作用。

Objective To explore the phenolic tetrahydro -β - carboline - arginine - glycine - aspartic acid （THBCB -RGD） peptidomimetic conjugates＇ role in myocardial ischemia- reperfusion inju- ry. Methods Using high performance liquid chromatography （HPLC） method to detect the stability of THBCB - RGD peptidomimetic conjugates. The oxyradical scavenging ability of THBCB - RGD peptidomitactic eonjugates was assessed by PCI2 cells survive experiment and aeetylcholine induced vasodilatation experiment assessment. The antiplatelet aggregation activity of THBCB - RGD peptidomimetic conjugates was evaluated by platelet aggregation exprement. Through the in vivo experiment, we evaluated the antithrombotic activity of THBCB - RGD peptidomimetie conjugates. Next, we constructed the cardiac ischemia reperfusion model and observe the effects of phenolic THBCB - RGD peptidomimetic conjugates on myocardial oxidative stress and myocardial infarction. Results HPLC results show that THBCB - RGD peptidomimetic conjugates has a strong ability of scavenging （exhaustion time： 240 min, 180 min, 240 min; RHBCB： 30 min; P = 0. 005）. NO, H2O2 and · OH as well as inhibiting platelet aggregation and thrombus formation （P =0. 004 or P =0. 000）. It can also inhibit the aggregation of platelets and the formation of thrombus （ P = 0. 003 or P = 0. 000）. In addition, treatment with phenolic tetrahydro - β - ear- holine- RGD peptidomimetic conjugates before the heart ischemia -reperfusion injury can decrease the MDA content in myoeardimn and reduce the myocardial infarction area. Conclusion THBCB - RGD peptidomimetic conjugates showed a strong ability of scavenging oxyradieal and anti - thrombosis. Addition,THBCB - RGD peptidomimetic conjugates play a protective role in cardiac isehemia - reperfusion injury by inhibiting oxidative stress and reducing the myocardial infarction area.