绿原酸预处理对大鼠心肌缺血再灌注损伤的保护作用

Protective Effect of Chlorogenic Acid Preconditioning on Myocardial Ischemia-reperfusion Injury in Rats

关键词:  绿原酸  缺血再灌注  机制

Key words:  chlorogenic acid  ischemia-reperfusion  mechanism

摘要:

目的 探讨绿原酸对大鼠心肌缺血再灌注（ischemia-reperfusion，I/R）损伤的保护作用及其对MEK/ERK信号通路的影响。方法 健康♂大鼠40只，随机分为假手术组、I/R组、I/R+绿原酸50 mg·kg^-1组、I/R+绿原酸50 mg·kg^-1+MEK抑制剂（AZD6244）15 μg·kg^-1组、I/R+AZD6244 15 μg·kg^-1组。连续灌胃给药2周后，采用结扎左冠状动脉前降支30 min、松开结扎线再灌注2 h建立I/R模型，并在再灌注2 h后收集标本，心脏组织进行氯化三苯基四氮唑法染色分析梗死面积，ELISA法检测血清中肌酸激酶同工酶（CK-MB）、乳酸脱氢酶（LDH）、白介素-6（IL-6）及肿瘤坏死因子-α（TNF-α）水平，Western blot检测MEK/ERK信号通路蛋白表达水平。结果 与假手术组相比，I/R组心肌梗死面积显著增加，血清中CK-MB、LDH、IL-6和TNF-α含量也显著升高，MEK、p-ERK蛋白表达水平也显著升高（P均<0.05）；与I/R组比较，I/R+绿原酸组、I/R+绿原酸+AZD6244组和I/R+AZD6244组心肌梗死面积显著减小，血清中CK-MB、LDH、IL-6和TNF-α含量也显著降低，MEK、p-ERK蛋白表达水平也显著降低（P均<0.05）。结论 绿原酸预处理可减轻大鼠心肌I/R损伤，机制可能与抑制MEK/ERK信号通路的活化有关。

Abstract:

OBJECTIIVE To observe the protective effects of chlorogenic acid against myocardial ischemia-reperfusion (I/R) injury and the effects of chlorogenic acid on the activation of MEK/ERK signaling pathway. METHODS Forty male SD rats were randomly divided into sham-operated group, I/R group, I/R+chlorogenic acid(50 mg·kg^-1) group, I/R+chlorogenic acid(50 mg·kg^-1)+MEK inhibitor(AZD6244, 15 μg·kg^-1) group, I/R+AZD6244(15 μg·kg^-1) group. Myocardial I/R model was established through ligation of the anterior descending branch of the left coronary artery for 30 min followed by reperfusion for 2 h after treatment for 2 weeks. The infarction area of myocardium were analyzed using triphenyltetrazolium chloride assay, serum levels of CK-MB, LDH, IL-6 and TNF-α were measured by ELISA kits, the expression levels of MEK and p-ERK were determined using Western blot assay. RESULTS Compared with sham-operated group, the infarction area of myocardium in I/R group was greatly increased, serum levels of CK-MB, LDH, IL-6 and TNF-α in I/R group were significantly increased, the expression levels of MEK and p-ERK were also greatly increased in I/R group (all P<0.05). Compared with I/R group, serum levels of CK-MB, LDH, IL-6 and TNF-α were significantly decreased in I/R+chlorogenic acid group, I/R+chlorogenic acid+AZD6244 group and I/R+AZD6244 group; the expression levels of MEK and p-ERK were significantly decreased in these groups(all P<0.05). CONCLUSION The protective effects of chlorogenic acid against myocardium against I/R injury in rats may involve in the inhibition of MEK/ERK signaling pathway activation.