摘要
目的：观察甘草酸预处理对大鼠心肌缺血再灌注损伤（myocardial ischemia reperfusion injury,MIRI）的保护作用及B细胞淋巴瘤/白血病-2原癌基因（B-cell lymphoma/leukemia-2,Bcl-2）和Bcl-2相关X蛋白（Bcl-2 associated X protein,Bax）表达的影响,探讨其可能机制。方法：50只SD大鼠随机分为假手术组,心肌缺血再灌注损伤组（模型组）,甘草酸预处理低、中、高剂量组。采用结扎左冠状动脉前降支建立大鼠心肌缺血再灌注损伤模型。假手术组穿线后不结扎;模型组于缺血前30 min腹腔注射2 mg·kg-1生理盐水;甘草酸低、中、高剂量组于缺血前30 min腹腔注射2,4,10 mg·kg-1甘草酸。光镜下观察心肌组织的病理组织学变化;检测肌酸激酶同工酶（CK-MB）活性,乳酸脱氢酶（LDH）活性,心肌肌钙蛋白-T（c Tn T）水平,肿瘤坏死因子-α（TNF-α）水平,白细胞介素-6（IL-6）水平,髓过氧化物酶（MPO）活性,超氧化物歧化酶（SOD）活性,谷胱甘肽过氧化物酶（GSH-Px）活性,丙二醛（MDA）水平;末端脱氧核苷酸转移酶介导的d UTP缺口末端标记测定法（TUNEL）检测心肌细胞凋亡指数;蛋白免疫印迹法（Western blot）检测心肌Bcl-2和Bax的表达。结果：与模型组比较,甘草酸预处理低剂量组、中剂量组、高剂量组明显减轻心肌缺血再灌注损伤;与模型组比较,甘草酸预处理低剂量组、中剂量组、高剂量组显著降低CKMB,LDH,c Tn T,TNF-α,IL-6,MPO,MDA水平,显著升高SOD,GSH-Px活性（P〈0.05,P〈0.01）;与模型组比较,甘草酸预处理低剂量组,中剂量组,高剂量组显著降低心肌细胞凋亡指数（P〈0.01）;与模型组比较,甘草酸预处理低、中、高剂量组显著上调心肌Bcl-2表达,下调Bax表达及上调Bcl-2/Bax（P〈0.05,P〈0.01）。结论：甘草酸预对大鼠心肌缺血再灌注损伤具有保护作用,且能上调心肌Bcl-2表达和下调心肌Bax表达,从而抑制细胞心肌凋亡。
Objective： To observe the protective effect and of pretreatment with glycyrrhizic acid on myocardial ischemia reperfusion injury（ MIRI） in rats and expressions of B-cell lymphoma/leukemia-2（ Bcl-2）and Bcl-2 associated X protein（ Bax）. Method： Fifty SD rats were randomly divided into sham operation group（ Sham group）,myocardial ischemia-reperfusion injury group（ MIRI group）,low-dose group,middle-dose group,and high-dose group. The myocardium ischemia reperfusion injury model in rats was established through ligation of the left anterior descending of the coronary artery. Rats in Sham group were not ligated after threading. Rats in MIRI group were administered with saline at the dose of 2 mg·kg-1 through intraperitoneal injection 30 minutes before ischemia. Low-dose group,middle-dose group and high-dose group were administered with glycyrrhizic acid at doses of 2,4 and 10 mg·kg-1 through intraperitoneal injection 30 minutes before ischemia. The pathological histologic changes in myocardial tissues were observed under optical microscope. Creatine kinase isoenzyme（ CKMB） activity,lactate dehydrogenase（ LDH） activity,cardiac troponin-T（ c Tn T）,tumor necrosis factor-α（ TNF-α）,interleukin-6（ IL-6）,myeloperoxidase（ MPO） activity,superoxide dismutase（ SOD） activity,glutathione peroxidase（ GSH-Px） activity and malondialdehyde（ MDA） were detected. Apoptotic index of myocardial cells was detected by terminal dexynucleotidyl transferase（ Td T）-mediated d UTP nick-end labeling（ TUNEL）,and expressions of Bcl-2 and Bax in cardiac muscle tissues were detected by Western blot. Result： Compared with MIRI group,myocardial ischemia reperfusion injury in rats was reduced significantly in low-dose group,middledose group and high-dose group. Compared with MIRI group,CK-MB activity,LDH activity,c Tn T,TNF-α,IL-6,MPO activity and MDA were significantly reduced in low-dose group,middle-dose group and high-dose group（ P〈0. 05,P〈0. 01）,while SOD activity and GSH-Px activity were significantly elevated in low-dose group,middledose group and high-dose group（ P〈0. 05,P〈0. 01）. Compared with MIRI group,apoptotic index of myocardial cells was significantly reduced in low-dose group,middle-dose group and high-dose group（ P〈0. 01）. Compared with MIRI group,expression of Bcl-2 in cardiac muscle tissues and ratio of Bcl-2,Bax were significantly elevated in low-dose group,middle-dose group and high-dose group（ P〈0. 05,P〈0. 01）,while expression of Bax in cardiac muscle tissues was significantly reduced in low-dose group,middle-dose group and high-dose group（ P〈0. 01）. Conclusion： Glycyrrhizic acid has a protective effect on myocardial ischemia reperfusion injury in rats by inhibiting apoptosis of myocardial cells,and can elevate expression of Bcl-2 and reduce expression of Bax in cardiac muscle tissues.
作者
王军
张虹
谢凤杰
李海红
WANG Jun1, ZHANG Hong2 , XIE Feng-jie2 , LI Hai-hong2(1. The First Hospital of Hainan Medical College, Haikou 570102, China; 2. Hongqi Hospital of Mudanfiang Medical University, Mudanjiaag 157011, Chin)
出处
《中国实验方剂学杂志》
CAS
CSCD
北大核心
2018年第6期126-132,共7页
Chinese Journal of Experimental Traditional Medical Formulae
基金
海南医学院创新性实验项目(HYCX2016-124)
