Gutteridge J M
Department of Anaesthesia and Intensive Care, Royal Brompton Hospital, London, England, UK.
Med Lab Sci. 1992 Dec;49(4):313-8.
Mammalian ageing is a universal phenomenon that is both obvious and inevitable, yet poorly understood, and under-researched at the molecular level. Numerous ageing theories have been proposed to explain the progressive and deleterious changes characteristic of ageing. One of the most popular of these is the 'free radical' theory of ageing, which proposes that ageing results from imperfect protection against tissue damage brought about by free radicals. Oxygen free radicals are constantly produced during aerobic metabolism, and certainly provide a universal mechanism for oxidative damage. However, a major obstacle to acceptance of the theory has been the poor record of antioxidants in prolonging the lifespan of small animals. Many other variables, such as genetic factors, temperature, activity and nutrition can affect lifespan, making it a highly complex multi-factorial process.
哺乳动物衰老虽是一种普遍现象，既明显又不可避免，但人们对其了解甚少，在分子层面的研究也不足。为解释衰老所特有的渐进性和有害变化，人们提出了众多衰老理论。其中最流行的一种是衰老的“自由基”理论，该理论认为衰老源于对自由基造成的组织损伤防护不力。有氧代谢过程中会不断产生氧自由基，这无疑为氧化损伤提供了一种普遍机制。然而，该理论被接受的一个主要障碍是抗氧化剂在延长小动物寿命方面效果不佳。许多其他变量，如遗传因素、温度、活动和营养等，都会影响寿命，使其成为一个高度复杂的多因素过程。
