葱白提取物对心肌缺血/再灌注损伤具有保护作用

目的 探讨葱白提取物(FOB)对心肌缺血/再灌注（I/R）损伤的影响及其机制。方法 结扎成年大鼠36只左冠状动脉前降支30 min，再灌注120 min建立在体心肌缺血/再灌注损伤模型；培养乳鼠心肌细胞缺氧6 h，复氧18 h建立离体心肌细胞缺氧/复氧(H/R)损伤模型。分别随机分为对照组、I/R组(或H/R组)和FOB预处理+I/R组(或H/R组)。应用PowerLab多通道生理记录仪分析左心室功能；2，3，5-三苯基四唑氯铵（TTC）染色检测心肌梗死体积。流式细胞术检测细胞凋亡率；Western blotting和Real-time PCR检测细胞凋亡相关蛋白和mRNA(Bcl-2、Bax、Caspase-3)的表达；免疫荧光检测细胞色素C(cytochrome C, Cyt-C)的表达。结果 在体大鼠实验中，与对照组比较，I/R组左心室收缩和舒张功能明显恶化(P<0.05)；与I/R组比较，FOB预处理能明显改善左心室收缩和舒张功能，且减小心肌梗死体积(P<0.05)。在培养心肌细胞实验中，与对照组比较，H/R组细胞凋亡率明显升高（P<0.01），Bcl-2蛋白及mRNA表达明显降低，而Bax、Caspase-3和Cyt-C的相关表达则明显升高(P<0.05)；与H/R组比较，FOB预处理显著降低细胞凋亡率(P<0.05)，增加Bcl-2蛋白及mRNA的表达水平，同时减少Bax、Caspase-3和Cyt-C的相关表达(P<0.05)。结论 葱白提取物对心肌缺血再灌注损伤具有保护作用，其机制可能是通过线粒体途径减少心肌细胞凋亡从而发挥作用。

Protective effect of fistular onion bulb extract on myocardial ischemia/reperfusion injury#br#

Objective To explore the effects of fistular onion bulb extract (FOB) on myocardial ischemia/reperfusion (I/R) injury and possible regulation mechanism.Methods The left anterior descending (LAD) artery of 36 adult rat heart was ligated for 30 minutes and subsequently released for 120 minutes to establish the I/R injury model in vivo. Cultured neonatal rat cardiomyocytes were subjected to 6 hours of hypoxia followed by 18 hours of reoxygenation to establish the hypoxia/reoxygenation (H/R) model in vitro. The rats or cardiomyocytes were randomly divided into the control group, I/R group (or H/R group) and FOB pretreatment+I/R group (or H/R group). The left ventricular (LV) function was measured using PowerLab multichannel physiological recorder; the infarct size was detected by 2,3,5-triphenyl tetrazolium chlorid(TTC) staining. The apoptosis rate was detected by flow cytometry, Western blotting and Real-time PCR were used to detect the expression of apoptosis-related proteins and mRNA (Bcl-2, Bax and Caspase-3); Immunofluorescence was used to detect the expression of cytochrome C(Cyt-C).Results In the animal experiments, compared with the control group, the left ventricular systolic and diastolic functions were deteriorated (P<0.05); compared with the I/R group, the pretreatment of FOB significantly improved the left ventricular systolic and diastolic function, and decreased the infarct size (P<0.05). In cultured cardiomyocytes, compared with the control group, the apoptosis rate was significantly increased (P<0.01), the protein and mRNA expression of Bcl-2 decreased, meanwhile the expression of Bax, Caspase-3 and Cyt-C increased in the H/R group (P<0.05); Compared with the H/R group, the pretreatment of FOB significantly reduced the apoptosis rate (P<0.05), increased the protein and mRNA expression of Bcl-2, at the same time, decreased the expression of Bax, Caspase-3 and Cyt-C(P<0.05).Conclusion Fistular onion bulb extract has the protective effect on myocardial ischemia/reperfusion injury, and its possible mechanism is to reduce cardiomyocyte apoptosis through mitochondrial pathway.