Meydani M, Lipman R D, Han S N, Wu D, Beharka A, Martin K R, Bronson R, Cao G, Smith D, Meydani S N
JM USDA-Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts, USA.
Ann N Y Acad Sci. 1998 Nov 20;854:352-60. doi: 10.1111/j.1749-6632.1998.tb09915.x.
The impact of diet and specific food groups on aging and age-associated degenerative diseases has been widely recognized in recent years. The modern concept of the free radical theory of aging takes as its basis a shift in the antioxidant/prooxidant balance that leads to increased oxidative stress, dysregulation of cellular function, and aging. In the context of this theory, antioxidants can influence the primary "intrinsic" aging process as well as several secondary age-associated pathological processes. For the latter, several epidemiological and clinical studies have revealed potential roles for dietary antioxidants in the age-associated decline of immune function and the reduction of risk of morbidity and mortality from cancer and heart disease. We reported that long-term supplementation with vitamin E enhances immune function in aged animals and elderly subjects. We have also found that the beneficial effect of vitamin E in the reduction of risk of atherosclerosis is, in part, associated with molecular modulation of the interaction of immune and endothelial cells. Even though the effects of dietary antioxidants on aging have been mostly observed in relation to age-associated diseases, the effects cannot be totally separated from those related to the intrinsic aging process. For modulation of the aging process by antioxidants, earlier reports have indicated that antioxidant feeding increased the median life span of mice to some extent. To further delineate the effect of dietary antioxidants on aging and longevity, middle-aged (18 mo) C57BL/6NIA male mice were fed ad libitum semisynthetic AIN-76 diets supplemented with different antioxidants (vitamin E, glutathione, melatonin, and strawberry extract). We found that dietary antioxidants had no effect on the pathological outcome or on mean and maximum life span of the mice, which was observed despite the reduced level of lipid peroxidation products, 4-hydroxynonenol, in the liver of animals supplemented with vitamin E and strawberry extract (1.34 +/- 0.4 and 1.6 +/- 0.5 nmol/g, respectively) compared to animals fed the control diet (2.35 +/- 1.4 nmol/g). However, vitamin E-supplemented mice had significantly lower lung viral levels following influenza infection, a viral challenge associated with oxidative stress. These and other observations indicate that, at present, the effects of dietary antioxidants are mainly demonstrated in connection with age-associated diseases in which oxidative stress appears to be intimately involved. Further studies are needed to determine the effect of antioxidant supplementation on longevity in the context of moderate caloric restriction.
近年来，饮食及特定食物类别对衰老和与年龄相关的退行性疾病的影响已得到广泛认可。现代衰老自由基理论的概念基于抗氧化剂/促氧化剂平衡的转变，这种转变会导致氧化应激增加、细胞功能失调以及衰老。在该理论背景下，抗氧化剂可影响主要的“内在”衰老过程以及一些与年龄相关的继发性病理过程。对于后者，多项流行病学和临床研究表明，膳食抗氧化剂在与年龄相关的免疫功能下降以及降低癌症和心脏病发病及死亡风险方面具有潜在作用。我们报道，长期补充维生素E可增强老年动物和老年受试者的免疫功能。我们还发现，维生素E在降低动脉粥样硬化风险方面的有益作用，部分与免疫细胞和内皮细胞相互作用的分子调节有关。尽管膳食抗氧化剂对衰老的影响大多是在与年龄相关疾病的背景下观察到的，但这些影响不能完全与那些与内在衰老过程相关的影响分开。关于抗氧化剂对衰老过程的调节作用，早期报告表明，喂食抗氧化剂在一定程度上增加了小鼠的平均寿命。为了进一步阐明膳食抗氧化剂对衰老和寿命的影响，对中年（18个月）C57BL/6NIA雄性小鼠随意喂食补充了不同抗氧化剂（维生素E、谷胱甘肽、褪黑素和草莓提取物）的半合成AIN - 76饮食。我们发现，膳食抗氧化剂对小鼠的病理结果、平均寿命和最大寿命均无影响，尽管与喂食对照饮食的动物相比，补充维生素E和草莓提取物的动物肝脏中脂质过氧化产物4 - 羟基壬烯醛的水平降低（分别为1.34±0.4和1.6±0.5 nmol/g，对照饮食组为2.35±1.4 nmol/g）。然而，补充维生素E的小鼠在感染流感后肺部病毒水平显著降低，流感是一种与氧化应激相关的病毒攻击。这些及其他观察结果表明，目前，膳食抗氧化剂的作用主要体现在与氧化应激似乎密切相关的年龄相关疾病中。需要进一步研究以确定在适度热量限制的情况下补充抗氧化剂对寿命的影响。
