CCR5抗体对大鼠心肌缺血再灌注损伤保护作用的机制研究

Protective Effects of CCR5 Antibody on Myocardial Ischemia-reperfusion Injury in Rats

目的通过使用趋化因子受体5(CCR5)的抗体作为拮抗剂及其配体作为激动剂结合预缺血处理对大鼠心肌缺血再灌注进行干预,观察干预后各种病理生理变化情况。方法建立大鼠心肌缺血再灌注模型及进行相应干预措施,监测大鼠心功能变化,苏木精-伊红(HE)染色检测心肌病理改变,试剂盒测定肌酸激酶(CK)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)及肿瘤坏死因子(TNF-α)、白细胞介素6(IL-6)含量,免疫组化检测细胞间粘附分子(ICAM-1)蛋白表达水平,荧光定量PCR(RT-PCR)及蛋白印迹法(Western blot)分别检测核转录因子(NF-κB)、CCR5的mRNA及蛋白表达量。结果相较心肌缺血再灌注组,CCR5抗体及预缺血处理能够显著降低大鼠血清中TNF-α、IL-6的含量,减轻NF-κB、CCR5的活化,抑制ICAM-1的表达,并缓解中性粒细胞在心肌组织中的聚集和粘附作用,减少心肌细胞中CK、AST、LDH等损伤标志酶的释放并增强心脏舒张和收缩能力;而CCR5激动剂处理则会恶化心肌病变情况,加重组织损伤程度。结论CCR5抗体能够改善大鼠心肌缺血再灌注损伤,减轻缺血部位炎症反应并起到明显的心肌保护作用。

Objective Chemokine receptor 5(CCR5)antibodies and ligands were used as antagonists and agonists respectively,and combined with ischemic preconditioning to treat myocardial ischemia-reperfusion in rats.Physiological and pathological changes were evaluated after treatment.Methods The rat model of myocardial ischemia-reperfusion was established with corresponding intervention measures,and changes in cardiac function were monitored.Myocardial pathological changes were observed by hematoxylin/eosin staining.The contents of CK,AST,LDH,TNF-αand IL-6 were evaluated by assay kits.The expression of ICAM-1 was examined by immunohistochemistry.The mRNA and protein expression of CCR5 and NF-κB was detected by RT-PCR and Western blotting,respectively.Results Compared with the myocardial ischemia-reperfusion group,CCR5 antibodies and pre-ischemic treatment significantly reduced the content of TNF-αand IL-6 in rats serum,decreased the activation of NF-κB and CCR5,and inhibited the expression of ICAM-1.They also alleviated neutrophil aggregation and adhesion in myocardial tissue,suppressed the release of CK,AST,and LDH,and increased the diastolic and contractility of the heart.Meanwhile,CCR5 agonists aggravated the condition of cardiomyopathy and the degree of tissue injury.Conclusion CCR5 antibodies can ameliorate myocardial ischemia-reperfusion injury in rats,alleviate inflammatory response at the ischemic site,and exert obvious protective effects on the myocardium.