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The Free Radical Theory of Aging and a Look at Changes in the Hypothalamus

Published online by Cambridge University Press:  29 November 2010

J. C. Carlson  and
M. Sawada
J. C. Carlson
Affiliation:
University of Waterloo
M. Sawada
Affiliation:
University of Waterloo
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Abstract

According to the free radical theory, aging is caused by the damaging effects of oxygen radicals. These agents are produced continuously and they become toxic when their intra-cellular levels become elevated. Although well-known for the damage they cause, recent studies indicate that free radicals may also have a beneficial side regulating some of the processes within a cell. With aging, however, it seems that the ability to control endogenous concentrations declines, and rising levels become progressively more harmful. In addition to the primary changes, the effects of free radical damage should also be examined at the secondary level. Because of its importance in regulating homeostatic mechanisms, it is possible that in this regard the hypothalamus may play a crucial role in the aging process. Progressive loss of function in this centre may lead to systemic changes which cause widespread disruption throughout the organism.

Résumé

Selon la théorie du radical libre, le vieillissement est produit par l'effet endommageant des radicaux d'oxygène. Ces radicaux sont produits de façon constante et deviennent toxiques quand le niveau de la concentration intracellulaire devient élevé. Malgré cet effet d'infamie, des études récentes indiquent qu'ils peuvent avoir un côté bénéfique en régulant certains mécanismes dans une cellule. Mais, avec le vieillissement, il semble que la capacité de réguler la concentration intracellulaire s'abaisse, et l'élévation du niveau devient toxique avec le temps. Il faut aussi examiner les effets endommageant des radicaux libres sur un niveau supérieur. À cause de la prééminence de l'hypothalamus comme centre régulateur homéostatique, il est possible que l'hypothalamus puisse jouer un rôle critique dans le processus de vieillissement. La perte progressive des fonctions dans ce centre peut mener à des changements systémiques qui peuvent provoquer des perturbations dans tout l'organisme.

Keywords

Free RadicalsAgingOxidative StressIntegrationHypothalamus.Radicaux libresvieillissementstress oxidatifintégrationhypothalamus.
Type
Articles
Information
Canadian Journal on Aging / La Revue canadienne du vieillissement , Volume 15 , Issue 1 , Spring/printemps 1996 , pp. 44 - 53
Copyright
Copyright © Canadian Association on Gerontology 1996

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