Journal article

Publication year: 2001

Pages: 224-230

Journal: Ernährungs-Umschau : Forschung & Praxis

Volume number: 48

Issue number: 6

ISSN: 0174-0008

Publisher: Umschau Verlag Breidenstein GMBH

Abstract: 

The various factors influencing the ageing process are controversially discussed in industrial societies. The most important theories of ageing can be divided into deterministic and stochastic models. Deterministic models imply that the ageing process is controlled by genetically determined programs or "biological clocks", such as telomere shortening, apoptosis, and evolutionary concepts. Stochastic models imply that ageing is caused by random, indiscriminate, and cumulative events such as the formation of "advanced glycosylation end products" or the toxic effects of reactive oxygen species (ROS). ROS are continuously generated in our body, e.g. by cell respiration, defense against infections, UV-radiation or signal transduction processes. Oxidative stress may oxidize proteins, initiate lipid peroxidation and lead to DNA alterations. Many of these damages accumulate during ageing and are involved in the pathobiochemistry of neurodegenerative and cardiovascular diseases. The observation that there is a correlation between the metabolic rate and life expectancy of a species led to the formulation of the "rate-of-living-hypothesis". Based on this hypothesis, the "free-radical theory of ageing" was formulated implying that a high metabolic rate is correlated with increased oxygen consumption, increased production of ROS, accumulating cell damage and - therefore - reduced life expectancy. 85% of cellular oxygen consumption takes place in mitochondria, i.e. in cell organelles which are particularly susceptible to oxidative stress. This might contribute to an energy deficit and impaired adaptation to environmental stress. Oxidative stress is antagonized by a number of enzymatic and non-enzymatic protective mechanisms. This is the reason why - apart from calorie restriction - strengthening of the antioxidative capacity of an individual is discussed as a contribution of nutritional sciences to the deceleration of the ageing process.

Harvard Citation style: Nickel, C. and Becker, K. (2001) Zur Biochemie des Alterns ernährungswissenschaftliche Aspekte des Redoxstoffwechsels, Ernährungs-Umschau : Forschung & Praxis, 48(6), pp. 224-230

APA Citation style: Nickel, C., & Becker, K. (2001). Zur Biochemie des Alterns ernährungswissenschaftliche Aspekte des Redoxstoffwechsels. Ernährungs-Umschau : Forschung & Praxis. 48(6), 224-230.