Borek C
Department of Community Health and Family Medicine, Nutrition and Infectious Diseases Unit, Tufts University School of Medicine, Boston, MA 02111, USA.
J Nutr. 2001 Mar;131(3s):1010S-5S. doi: 10.1093/jn/131.3.1010S.
Oxidative modification of DNA, proteins and lipids by reactive oxygen species (ROS) plays a role in aging and disease, including cardiovascular, neurodegenerative and inflammatory diseases and cancer. Extracts of fresh garlic that are aged over a prolonged period to produce aged garlic extract (AGE) contain antioxidant phytochemicals that prevent oxidant damage. These include unique water-soluble organosulfur compounds, lipid-soluble organosulfur components and flavonoids, notably allixin and selenium. Long-term extraction of garlic (up to 20 mo) ages the extract, creating antioxidant properties by modifying unstable molecules with antioxidant activity, such as allicin, and increasing stable and highly bioavailable water-soluble organosulfur compounds, such as S-allylcysteine and S-allylmercaptocysteine. AGE exerts antioxidant action by scavenging ROS, enhancing the cellular antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase, and increasing glutathione in the cells. AGE inhibits lipid peroxidation, reducing ischemic/reperfusion damage and inhibiting oxidative modification of LDL, thus protecting endothelial cells from the injury by the oxidized molecules, which contributes to atherosclerosis. AGE inhibits the activation of the oxidant-induced transcription factor, nuclear factor (NF)-kappa B, which has clinical significance in human immunodeficiency virus gene expression and atherogenesis. AGE protects DNA against free radical--mediated damage and mutations, inhibits multistep carcinogenesis and defends against ionizing radiation and UV-induced damage, including protection against some forms of UV-induced immunosuppression. AGE may have a role in protecting against loss of brain function in aging and possess other antiaging effects, as suggested by its ability to increase cognitive functions, memory and longevity in a senescence-accelerated mouse model. AGE has been shown to protect against the cardiotoxic effects of doxorubicin, an antineoplastic agent used in cancer therapy and against liver toxicity caused by carbon tetrachloride (an industrial chemical) and acetaminophen, an analgesic. Substantial experimental evidence shows the ability of AGE to protect against oxidant-induced disease, acute damage from aging, radiation and chemical exposure, and long-term toxic damage. Although additional observations are warranted in humans, compelling evidence supports the beneficial health effects attributed to AGE, i.e., reducing the risk of cardiovascular disease, stroke, cancer and aging, including the oxidant-mediated brain cell damage that is implicated in Alzheimer's disease.
活性氧（ROS）对DNA、蛋白质和脂质的氧化修饰在衰老及包括心血管疾病、神经退行性疾病、炎症性疾病和癌症在内的多种疾病中发挥作用。新鲜大蒜经过长时间陈化制成的陈化大蒜提取物（AGE）含有可防止氧化损伤的抗氧化植物化学物质。这些物质包括独特的水溶性有机硫化合物、脂溶性有机硫成分和类黄酮，尤其是蒜辣素和硒。大蒜的长期提取（长达20个月）使提取物陈化，通过修饰具有抗氧化活性的不稳定分子（如蒜素）并增加稳定且生物利用度高的水溶性有机硫化合物（如S-烯丙基半胱氨酸和S-烯丙基巯基半胱氨酸）来产生抗氧化特性。AGE通过清除ROS、增强细胞抗氧化酶超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶以及增加细胞内谷胱甘肽来发挥抗氧化作用。AGE抑制脂质过氧化，减少缺血/再灌注损伤并抑制低密度脂蛋白的氧化修饰，从而保护内皮细胞免受氧化分子的损伤，而氧化分子会导致动脉粥样硬化。AGE抑制氧化应激诱导的转录因子核因子（NF）-κB的激活，这在人类免疫缺陷病毒基因表达和动脉粥样硬化形成中具有临床意义。AGE保护DNA免受自由基介导的损伤和突变，抑制多步骤致癌过程，并抵御电离辐射和紫外线诱导的损伤，包括对某些形式的紫外线诱导的免疫抑制的保护作用。如在衰老加速小鼠模型中其增加认知功能、记忆力和寿命的能力所示AGE可能在预防衰老过程中的脑功能丧失方面发挥作用并具有其他抗衰老作用。AGE已被证明可预防多柔比星（一种用于癌症治疗的抗肿瘤药物）的心脏毒性作用以及由四氯化碳（一种工业化学品）和对乙酰氨基酚（一种镇痛药）引起的肝毒性。大量实验证据表明AGE具有预防氧化应激诱导的疾病、衰老、辐射和化学暴露引起的急性损伤以及长期毒性损伤的能力。尽管还需要在人体中进行更多观察，但有力证据支持AGE对健康的有益作用，即降低心血管疾病、中风、癌症和衰老的风险，包括与阿尔茨海默病相关的氧化应激介导的脑细胞损伤。
