Breinholt Vibeke M, Nielsen Salka E, Knuthsen Pia, Lauridsen Soren T, Daneshvar Bahram, Sorensen Annemarie
Institute of Food Safety and Nutrition, Division of Biochemical Toxicology, The Danish Veterinary and Food Administration, Morkhoj Bygade 19, 2860 Soborg, Denmark.
Nutr Cancer. 2003;45(1):46-52. doi: 10.1207/S15327914NC4501_6.
Administration of apple juice, black currant juice, or a 1:1 combination of the two juices significantly decreased the level of the lipid peroxidation biomarker malondialdehyde in plasma of female rats, whereas the protein oxidation biomarker 2-amino-adipic semialdehyde, was significantly increased following administration of orange juice, black currant juice, or the 1:1 combination of apple and black currant juice. A significant increase in 2-amino-adipic semialdehyde was also observed in control rats given sucrose, fructose, and glucose in the drinking water at concentrations approximating the average carbohydrate levels in the employed fruit juices. None of the fruit juices were found to affect the activities of antioxidant enzymes in red blood cells or hepatic glutathione S-transferase. Hepatic quinone reductase activity, on the other hand, was significantly increased by grapefruit juice, apple juice, and black currant juice. The total daily intake of a selected subset of flavonoid aglycones ranged from 0.2 to 4.3 mg, and quercetin was found to be a minor constituent of all the juices investigated. In a parallel study, rats were fed quercetin at doses ranging from 0.001 to 10 g/kg of diet. However, no effects were observed on hepatic glutathione S-transferase or quinone reductase activities, plasma redox status, or the activity of red blood cell antioxidant enzymes. Overall, the results of the present study suggest that commonly consumed fruit juices can alter lipid and protein oxidation biomarkers in the blood as well as hepatic quinone reductase activity, and that quercetin may not be the major active principle. The observation that natural carbohydrates are capable of mediating oxidative stress in vivo warrants further studies due to the central role refined and unrefined carbohydrates play in human nutrition.
给雌性大鼠灌胃苹果汁、黑加仑汁或二者1:1混合的果汁，可显著降低血浆中脂质过氧化生物标志物丙二醛的水平；而给予橙汁、黑加仑汁或苹果汁与黑加仑汁1:1混合的果汁后，蛋白质氧化生物标志物2-氨基己二酸半醛水平显著升高。在饮用水中添加蔗糖、果糖和葡萄糖且浓度接近所用果汁中平均碳水化合物水平的对照大鼠中，也观察到2-氨基己二酸半醛显著增加。未发现任何一种果汁会影响红细胞中的抗氧化酶活性或肝脏谷胱甘肽S-转移酶活性。另一方面，葡萄柚汁、苹果汁和黑加仑汁可显著提高肝脏醌还原酶活性。所选类黄酮苷元子集的每日总摄入量在0.2至4.3毫克之间，并且发现槲皮素是所有研究果汁中的次要成分。在一项平行研究中，给大鼠喂食剂量范围为0.001至10克/千克体重的槲皮素。然而，未观察到对肝脏谷胱甘肽S-转移酶或醌还原酶活性、血浆氧化还原状态或红细胞抗氧化酶活性有任何影响。总体而言，本研究结果表明，常见的食用果汁可改变血液中的脂质和蛋白质氧化生物标志物以及肝脏醌还原酶活性，并且槲皮素可能不是主要的活性成分。鉴于精制和未精制碳水化合物在人类营养中所起的核心作用，天然碳水化合物能够在体内介导氧化应激这一观察结果值得进一步研究。
