阿里红多糖对大鼠心肌缺血再灌注损伤的保护作用及其机制研究

Protective effect and mechanism of polysaccharide from Fomes Officinalis Ames on myocardial ischemia⁃reperfusion injury in rats

目的探讨阿里红多糖对大鼠心肌缺血再灌注损伤(myocardial ischemia/reperfusion injury,MIRI)的保护作用及其作用机制。方法采用冠状动脉左前降支结扎法建立MIRI模型,将60只SPF级SD大鼠按体质量随机分别为假手术组、模型组、地塞米松组(DEX组)、阿里红多糖低剂量组(ALH-L组)、中剂量组(ALH-M组)和高剂量组(ALH-H组)。各给药组于造模前预防给药1周,其中DEX组灌胃给予地塞米松0.8 mg/(kg·d),ALH-L、M、H组分别灌胃给予阿里红多糖10、20、40 mg/(kg·d),而假手术组和模型组灌胃给予等量生理盐水。造模24 h后取材,NBT染色法观察各组大鼠心肌梗死面积;化学比色法测定血浆TNF-α、IL-1β、MDA含量和CK、LDH、SOD活性;Western blotting法检测心肌组织Bcl-2和caspase-3的表达量。结果与假手术组比较,模型组的心电图ST段、心脏梗死率、血浆CK、LDH活性,TNF-α、IL-1β、MDA含量和心肌组织caspase-3的表达量明显升高(P<0.01),血浆SOD活性和心肌组织Bcl-2表达量明显降低(P<0.01)。与模型组比较,ALH-L、M、H组均明显降低心电图ST段/心脏梗死率、血浆CK、LDH活性,TNF-α、IL-1β、MDA含量和心肌组织caspase-3的表达量(P<0.05),升高血浆SOD活性和心肌组织Bcl-2表达量(P<0.05),并呈剂量依赖性。结论阿里红多糖对大鼠心肌缺血再灌注损伤具有较好的保护作用,其作用机制可能与抗氧化、抗炎和抗凋亡作用有关。

Objective To study the protective effect and mechanism of polysaccharide from Fomes Officinalis Ames on myocardial ischemia-reperfusion injury(MIRI)in rats.Methods The rat model of MIRI was established by ligation of left coronary artery.60 SPF SD rats were randomly divided into the sham group,the model group,DEX group,ALH-L group,ALH-M group and ALH-H group.The feed doses of DEX group,ALH-L group,ALHM group and ALH-H group were 0.8 mg/(kg·d),10 mg/(kg·d),20 mg/(kg·d)and 40 mg/(kg·d)separately for one week.The sham group and model group were gave the same dose of sodium chloride.All samples were obtained after 24 h modeling.The myocardial infarction area of rats in each group was observed by NBT staining.The contents of TNF-α,IL-1β,MDA and activity of CK,LDH and SOD were determined by chemical colorimetry.The expression of Bcl-2 and caspase-3 in myocardial tissue was detected by Western blotting.Results Compare with the sham group,ST segment of electrocardiogram,cardiac infarction rate,the activities of CK and LDH,the contents of TNF-α,IL-1βand MDA,and caspase-3 expression were increased,while the SOD activity and Bcl-2 expression were decreased in the model group.Compare with model group,ST segment of electrocardiogram,cardiac infarction rate,the activities of CK and LDH,the contents of TNF-α,IL-1βand MDA,and caspase-3 expression were decreased,while the SOD activity and Bcl-2 expression were increased in three ALH groups in a dose-dependent fashion.Conclusion Polysaccharide from Fomes Officinalis Ames displays a good protective effect on myocardial ischemia-reperfusion injury in rats,and its mechanism may be related to antioxidant,antiinflammatory and anti-apoptotic effects.