Harman D
University of Nebraska College of Medicine, Omaha 68198-4635.
EXS. 1992;62:1-10. doi: 10.1007/978-3-0348-7460-1_1.
Aging is the accumulation of changes responsible for the sequential alterations that accompany advancing age and the associated progressive increases in the chance of disease and death. These changes can be attributed to disease, environment, and the inborn aging process. The aging process is now the major risk factor for disease and death after about age 28. The free radical theory of aging arose in 1954 from a consideration of aging phenomenon from the premise that a single common process, modifiable by genetic and environmental factors, was responsible for the aging and death of all living things. The theory postulates that aging is caused by free radical reactions, i.e., these reactions may be involved in production of the aging changes associated with the environment, disease and the intrinsic aging process. The origination of the theory and its application to the problem of increasing the functional life span are discussed. Support for the free radical theory of aging has increased progressively and now includes: 1) studies on the origin of life and evolution, 2) studies on the effect of ionizing radiation on living things, 3) dietary manipulations of endogenous free radical reactions, 4) the plausible explanations it provides for aging phenomena, and 5) the growing numbers of studies that implicate free radical reactions in the pathogenesis of specific diseases. The rapidly growing number of scientists involved in studies on the role of free radical reactions in biological systems should assure future significant increases in the healthy, useful, life span of man.
衰老指的是一系列变化的积累，这些变化导致了随着年龄增长而出现的相继改变，以及疾病和死亡几率的相应逐步增加。这些变化可归因于疾病、环境和内在的衰老过程。大约在28岁之后，衰老过程成为疾病和死亡的主要风险因素。衰老的自由基理论于1954年提出，它是从这样一个前提来考虑衰老现象的：即一个单一的共同过程，可由遗传和环境因素改变，是所有生物衰老和死亡的原因。该理论假定衰老是由自由基反应引起的，也就是说，这些反应可能参与了与环境、疾病和内在衰老过程相关的衰老变化的产生。本文讨论了该理论的起源及其在延长功能寿命问题上的应用。对衰老自由基理论的支持逐渐增加，目前包括：1）关于生命起源和进化的研究；2）关于电离辐射对生物影响的研究；3）对内源性自由基反应的饮食调控；4）它对衰老现象提供的合理阐释；5）越来越多的研究表明自由基反应与特定疾病的发病机制有关。参与自由基反应在生物系统中作用研究的科学家数量迅速增加，这应能确保人类健康、有用的寿命在未来显著延长。
