积雪草苷对大鼠缺血再灌注心肌细胞保护作用研究

The protective effect of Asiaticoside on myocardial ischemia- reperfusion injury in rats

目的研究积雪草苷(asiaticoside,AC)对在体大鼠心肌缺血再灌注损伤的保护作用,初步探讨其机制。方法40只SPF级Wistar大鼠,随机分为假手术组(SH组)、心肌缺血再灌注模型组(IR组)、积雪草苷低剂量组(ACL组)、积雪草苷中剂量组(AC-M组)及积雪草苷高剂量组(AC-H组),各8只。积雪草苷低、中、高剂量组分别以0.25、0.50、1.00 ml/100g体重的剂量连续灌胃14 d,药液浓度1.5 mg/ml。其它各组以0.5%羧甲基纤维素钠溶液灌胃。除SH组外,其它各组结扎左冠状动脉前降支,使心肌缺血30 min,再灌注60 min。检测血清中超氧化物歧化酶(superoxide dismutase,SOD)、乳酸脱氢酶(lactic acid dehydrogenase,LDH)、肌酸激酶(creatine kinase,CK)活性和丙二醛(malondialdehyde,MDA)含量;ELISA法测定血清中C反应蛋白(C-reactive protein,CRP)含量;TUNEL法检测各组大鼠缺血心肌细胞凋亡;RT-PCR法检测B细胞白血病/淋巴瘤-2基因(B-cell leukemia/lymphoma 2,Bcl-2)和与Bcl-2相关的x蛋白(Bcl-2 associated x protein,Bax)的m RNA表达。计量资料两组间比较采用t检验,多组间比较采用单因素方差分析,P<0.05为差异有统计学意义。结果与IR组比,积雪草苷各剂量组均能降低血清中LDH、CK-MB活性及MDA含量,升高血清中SOD活性,降低血清中CRP含量,降低心肌细胞凋亡指数,差异均有统计学意义(均P<0.05)。积雪草苷各组凋亡基因Bcl-2表达水平上升,Bax表达水平下降,Bcl-2/Bax比值升高,差异均有统计学意义(均P<0.05)。结论积雪草苷预处理能通过减少心肌细胞凋亡、抗脂质过氧化物产生及抗炎症反应等机制,对心肌缺血再灌注损伤产生保护作用。

Objective To explore the protective effect of asiaticoside （AC） on myocardial ischemia - reperfusion injury in rats,and explore the protective mechanisms. Methods 40 SPF Wistar rats were selected and randomly divided into sham - operated group （ SH group）, myocardial ischemia - reperfusion model group （IR） , asiaticoside low - dose group （ AC - L group）, asiaticoside middle - dose group （ AC - M group） and asiaticoside high - dose group （ AC - H group）, each group had 8 rats. Rats in the asiaticoside low, middle and high - dose groups were administered with asiaticoside （ at the dose of 0.25 ml/100g,0.5 ml/100g and I. 0 ml/100g） by gastregavage for 14 days ,the drug concentration was 1.5 rag/ nil. While other groups were given 0.5 % solution of sodium carboxymethyl cellulose by gastrogavage at the same time. Ex- cept the SH group, in other groups left anterior descending coronary artery was ligated, the time of myocardial ischemia was 30 min, and the time of reperfusion was 60 min. The serum superoxide dismutase （ SOD）, lactate dehydrogenase （ LDH）, ereatine kinase （CK） activity and malondialdehyde （MDA） content were detected, serum C -reactive protein （CRP） con- tent was measured by ELISA. The isehemic myocardium apoptosis was detected by TUNEL method. The mRNA expressions of B - cell leukemia/lymphoma 2 （ Bcl - 2） and Bcl - 2 associated x protein （Bax） were detected by RT - PCR. Measure- ment data between two groups using t test, compared among groups by single factor analysis of variance, P 〈 0.05 for the difference had statistical significance. Results Compared with the IR group,each dose group of asiaticoside could signifi- cantly reduce serum LDH, CK and MDA, significantly elevated serum SOD activity,significantly decreased serum CRP lev- els, and significantly reduced myocardial apoptosis index, the differences were statistically significant （ all P 〈 0.05）. Each dose group of asiaticoside could increase the expression leved of Bcl -2,decrease the expression leved of Bax,increase the ratio of Bel - 2/Bax, the differences were statistically significant （ all P 〈 O. 05 ）. Conclusions Asiaticoside by pretreat- ment has the protective effect on myocardial ischemia and reperfusion injury in rats, which may be related with the mecha- nisms of reducing myocardial apoptosis, anti - lipid peroxides and anti - inflammatory.