Ang-1模拟肽协同血管内皮生长因子对心肌梗死大鼠心脏功能的影响

EFFECTS OF Ang-1 MIMICKING PEPTIDE IN SYNERGY WITH VASCULAR ENDOTHELIAL GROWTH FACTOR ON CARDIAC FUNCTION IN RATS WITH MYOCARDIAL INFARCTION

目的观察心脏细胞外基质(c-ECM)结合胶原靶向血管内皮生长因子(CBD-VEGF)和Ang-1模拟肽(AMP)对心肌梗死大鼠心脏功能的影响。方法对AMP行MTT体外人脐静脉内皮细胞(HUVEC)活性试验及对修饰了Biotin的AMP(Bio-AMP)进行与c-ECM的结合试验。将SD大鼠行左前降支结扎构建心肌梗死模型,然后随机分为PBS组(A组)、c-ECM/CBD-VEGF组(B组)和CBD-VEGF/c-ECM/AMP组(C组),每组4只,分别于梗死部位注射PBS、CBD-VEGF/c-ECM和CBD-VEGF/c-ECM/AMP进行治疗。3个月后采用超声心动图评价3组大鼠的心脏功能,采用免疫荧光染色方法检测3组大鼠心肌梗死区域血管数量、vWF阳性面积比和ZO1阳性面积比。结果MTT试验检测结果显示,AMP和Ang-1具有相似的促进HUVEC增殖的能力;结合实验结果显示,Bio-AMP可以连接在c-ECM上。处理3个月后,C组大鼠术后心脏射血分数(EF)显著高于A组和B组(t=7.794、3.613,P<0.05)。大鼠心肌梗死区域免疫荧光染色显示,C组血管数量和vWF阳性面积比高于A组(t=4.950、22.390,P<0.05),并且C组vWF阳性面积比显著高于B组(t=11.400,P<0.05)。C组和B组的ZO1阳性面积比明显高于A组(t=13.290、4.328,P<0.05),C组的ZO1阳性面积比明显高于B组(t=8.243,P<0.05)。结论将本研究合成的CBD-VEGF/c-ECM/AMP水凝胶注射于大鼠心肌梗死区域后具有促进大鼠心脏功能恢复和促进心肌梗死后血管再生及细胞连接的作用。

Objective To investigate the effects of cardiac extracellular matrix(c-ECM)combined with collagen-binding vascular endothelial growth factor(CBD-VEGF)and Ang-1 mimicking peptide(AMP)on cardiac function in rats with myocardial infarction(MI).Methods MTT assay was used to measure the activity of AMP in human umbilical vein endothelial cells(HUVECs)in vitro,and the binding of Biotin-modified AMP(Bio-AMP)to c-ECM was tested.A myocardial infarction model was established by ligation of the left anterior descending artery in SD rats.The rats were randomly divided into PBS group(group A),c-ECM/CBD-VEGF group(group B),and CBD-VEGF/c-ECM/AMP group(group C),with four rats in each group.The rats were treated by injection of PBS,CBD-VEGF/c-ECM,or CBD-VEGF/c-ECM/AMP at the infarct site.After 3 months of treatment,echocardiography was used to evaluate the cardiac function of rats in the three groups.Immunofluorescence staining was used to determine the number of blood vessels as well as the ratios of vWF positive area and ZO1 positive area in the myocardial infarction area.Results MTT assay showed that AMP and Ang-1 had similar ability to promote the proliferation of HUVECs.The binding experiment showed that Bio-AMP could be attached to c-ECM.After 3 months of treatment,the ejection fraction was significantly higher in group C than in group A and group B(t=7.794,3.613,P<0.05).Immunofluorescence staining showed that the number of blood vessels and the ratio of vWF positive area were significantly higher in group C than in group A(t=4.950,22.390,P<0.05),and the ratio of vWF positive area was significantly higher in group C than in group B(t=11.400,P<0.05).The ZO1 positive area ratio was significantly higher in group C and group B than in group A(t=13.290,4.328,P<0.05).The ZO1 positive area ratio was significantly higher in group C than in group B(t=8.243,P<0.05).Conclusion Injection of the CBD-VEGF/c-ECM/AMP hydrogel synthesized in this study at the myocardial infarction area can promote the recovery of cardiac function and enhance angiogenesis and cell connection in rats after myocardial infarction.