Euterpe Oleracea Mart. (Açaí) Reduces Oxidative Stress and Improves Energetic Metabolism in Myocardial Ischemia-Reperfusion Injury in Rats

Abstract Background: Euterpe oleracea Mart. (açaí) is a fruit with high antioxidant capacity and could be an adjuvant strategy to attenuate ischemia-reperfusion injury. Objective: To evaluate the influence of açaí in global ischemia-reperfusion model in rats. Methods: Wistar rats were assigned to 2 groups: Control (C: receiving standard chow; n = 9) and Açaí (A: receiving standard chow supplemented with 5% açaí; n = 10). After six weeks, the animals were subjected to the global ischemia-reperfusion protocol and an isolated heart study to evaluate left ventricular function. Level of significance adopted: 5%. Results: There was no difference between the groups in initial body weight, final body weight and daily feed intake. Group A presented lower lipid hydroperoxide myocardial concentration and higher catalase activity, superoxide dismutase and glutathione peroxidase than group C. We also observed increased myocardial activity of b-hydroxyacyl coenzyme-A dehydrogenase, pyruvate dehydrogenase, citrate synthase, complex I, complex II and ATP synthase in the A group as well as lower activity of the lactate dehydrogenase and phosphofructokinase enzymes. The systolic function was similar between the groups, and the A group presented poorer diastolic function than the C group. We did not observe any difference between the groups in relation to myocardial infarction area, total and phosphorylated NF-kB, total and acetylated FOXO1, SIRT1 and Nrf-2 protein expression. Conclusion: despite improving energy metabolism and attenuating oxidative stress, açai supplementation did not decrease the infarcted area or improve left ventricular function in the global ischemia-reperfusion model.

摘要 背景：紫果西谷椰子（Euterpe oleracea Mart.，俗称阿萨伊果（açaí））是一种抗氧化能力优异的果实，可作为减轻缺血-再灌注损伤的辅助干预策略。目的：评估阿萨伊果（açaí）对大鼠全心缺血-再灌注模型的影响。方法：将Wistar大鼠随机分为2组：对照组（C组：饲喂标准饲料，n=9）与阿萨伊果组（A组：饲喂添加5%阿萨伊果的标准饲料，n=10）。饲养6周后，对大鼠实施全心缺血-再灌注造模，并开展离体心脏实验以评估左心室功能。检验水准设定为5%。结果：两组大鼠初始体质量、终末体质量及每日摄食量均无显著差异。与对照组相比，A组大鼠心肌脂质氢过氧化物浓度更低，过氧化氢酶、超氧化物歧化酶与谷胱甘肽过氧化物酶活性更高。此外，A组大鼠心肌β-羟酰辅酶A脱氢酶、丙酮酸脱氢酶、柠檬酸合酶、呼吸链复合体I、呼吸链复合体II及ATP合酶活性均有所升高，而乳酸脱氢酶与磷酸果糖激酶活性则显著降低。两组大鼠收缩功能无明显差异，但A组舒张功能较对照组更差。两组大鼠心肌梗死面积、总核因子κB（NF-κB）与磷酸化核因子κB、总叉头框蛋白O1（FOXO1）与乙酰化叉头框蛋白O1、沉默信息调节因子1（SIRT1）及核因子红细胞2相关因子2（Nrf-2）的蛋白表达水平均无显著差异。结论：尽管阿萨伊果补充可改善能量代谢并减轻氧化应激，但在全心缺血-再灌注模型中，其并未缩小心肌梗死面积或改善左心室功能。