目的 探討芒果苷(MGF)預(yù)處理對(duì)大鼠心肌缺血再灌注(MI/R)損傷的保護(hù)作用及機(jī)制。方法 SD大鼠隨機(jī)分為5組,即假手術(shù)組、模型組和MGF高、中、低劑量(40、20、10 mg/kg)組,采用結(jié)扎左冠脈前降支30 min再灌注2 h的方法制備大鼠MI/R損傷模型,于術(shù)前7 d開始ig給藥。采用比色法測(cè)定血清肌酸激酶(CK)和乳酸脫氫酶(LDH)活性,ELISA法測(cè)定血清腫瘤壞死因子-α(TNF-α)和白細(xì)胞介素-1β(IL-1β)水平;染色法測(cè)定心肌梗死面積(MIS);取心肌勻漿,比色法測(cè)定髓過氧化物酶(MPO)活性。結(jié)果 與模型組比較,MGF高、中劑量組MIS、血清LDH活性顯著降低(P<0.05);MGF各劑量組血清CK活性、血清TNF-α和IL-1β水平、心肌MPO活性明顯降低(P<0.05、0.01)。結(jié)論 MGF預(yù)處理通過抑制中性粒細(xì)胞浸潤,下調(diào)TNF-α和IL-1β表達(dá),抑制炎癥反應(yīng),發(fā)揮對(duì)MI/R所致心肌損傷的保護(hù)作用。

Objective To investigate the protective effects of mangiferin (MGF) against myocardial ischemia/reperfusion (MI/R) injury in rats. Methods Rat model of MI/R injury was established by coronary artery ligation for 30 min followed by 2 h reperfusion. Rats were divided randomly into five groups: Sham group, model group, MGF 10, 20, and 40 mg/kg group. MGF was ig administered once daily for 7 d pre-operation. The CK and LDH activities in sera were detected by chromatometry and the levels of TNF-α and IL-1β in sera were examined by ELISA after reperfusion. The myocardial infarction size (MIS) was measured by NBT staining. The MPO activity, an index of neutrophil infiltration in heart homogenate, was determined by chromatometry. Results MGF (40 and 20 mg/kg) significantly reduced MIS and LDH activities comparing to that of model group (P < 0.05). The activity of CK in sera and MPO in heart homogenate, the levels of IL-1β and TNF-α in sera, in all MGF groups were significantly lower than those of model group (P < 0.05, 0.01). Conclusion The myocardial protection of MGF pretreatment in MI/R injury appears to be associated with the inhibition of neutrophil infiltration, expression of TNF-α and IL-1β and inflammatory response.