Quick Kevin L, Ali Sameh S, Arch Robert, Xiong Chengjie, Wozniak David, Dugan Laura L
Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, United States.
Neurobiol Aging. 2008 Jan;29(1):117-28. doi: 10.1016/j.neurobiolaging.2006.09.014. Epub 2006 Oct 31.
In lower organisms, such as Caenorhabditis elegans and Drosophila, many genes identified as key regulators of aging are involved in either detoxification of reactive oxygen species or the cellular response to oxidatively-damaged macromolecules. Transgenic mice have been generated to study these genes in mammalian aging, but have not in general exhibited the expected lifespan extension or beneficial behavioral effects, possibly reflecting compensatory changes during development. We administered a small-molecule synthetic enzyme superoxide dismutase (SOD) mimetic to wild-type (i.e. non-transgenic, non-senescence accelerated) mice starting at middle age. Chronic treatment not only reduced age-associated oxidative stress and mitochondrial radical production, but significantly extended lifespan. Treated mice also exhibited improved performance on the Morris water maze learning and memory task. This is to our knowledge the first demonstration that an administered antioxidant with mitochondrial activity and nervous system penetration not only increases lifespan, but rescues age-related cognitive impairment in mammals. SOD mimetics with such characteristics may provide unique complements to genetic strategies to study the contribution of oxidative processes to nervous system aging.
在诸如秀丽隐杆线虫和果蝇等低等生物中,许多被鉴定为衰老关键调节因子的基因都参与了活性氧的解毒过程或细胞对氧化损伤大分子的反应。已培育出转基因小鼠来研究这些基因在哺乳动物衰老中的作用,但总体上并未表现出预期的寿命延长或有益的行为效应,这可能反映了发育过程中的补偿性变化。我们从中年开始给野生型(即非转基因、非衰老加速型)小鼠施用一种小分子合成酶超氧化物歧化酶(SOD)模拟物。长期治疗不仅降低了与年龄相关的氧化应激和线粒体自由基产生,还显著延长了寿命。接受治疗的小鼠在莫里斯水迷宫学习和记忆任务中的表现也有所改善。据我们所知,这是首次证明一种具有线粒体活性且能穿透神经系统的施用抗氧化剂不仅能延长寿命,还能挽救哺乳动物与年龄相关的认知障碍。具有此类特性的SOD模拟物可能为研究氧化过程对神经系统衰老的贡献的遗传策略提供独特的补充。