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This Article Full Text Full Text (PDF) All Versions of this Article: 293/4/C1302    most recent 00203.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Valle, A. Articles by Oliver, J. Search for Related Content PubMed PubMed Citation Articles by Valle, A. Articles by Oliver, J.

CELLULAR METABOLISM

Sexual dimorphism in liver mitochondrial oxidative capacity is conserved under caloric restriction conditions

Grup de Metabolisme Energètic i Nutrició, Departament de Biologia Fonamental i Ciències de la Salut; Institut Universitari d'Investigació en Ciències de la Salut, Universitat de les Illes Balears, and Ciber Fisiopatología Obesidad y Nutrición (CB06/03) Instituto Salud Carlos III, Palma de Mallorca; Spain

Submitted 17 May 2007 ; accepted in final form 19 July 2007

Caloric restriction (CR) without malnutrition has been shown to increase maximal life span and delay the rate of aging in a wide range of species. It has been proposed that reduction in energy expenditure and oxidative damage may explain the life-extending effect of CR. Sex-related differences also have been shown to influence longevity and energy expenditure in many mammalian species. The aim of the present study was to determine the sex-related differences in rat liver mitochondrial machinery, bioenergetics, and oxidative balance in response to short-term CR. Mitochondria were isolated from 6-mo-old male and female Wistar rats fed ad libitum or subjected to 40% CR for 3 mo. Mitochondrial O₂ consumption, activities of the oxidative phosphorylation system (complexes I, III, IV, and V), antioxidative activities [MnSOD, glutathione peroxidase (GPx)], mitochondrial DNA and protein content, mitochondrial H₂O₂ production, and markers of oxidative damage, as well as cytochrome C oxidase and mitochondrial transcription factor A levels, were measured. Female rats showed a higher oxidative capacity and GPx activity than males. This sexual dimorphism was not modified by CR. Restricted rats showed slightly increased oxygen consumption, complex III activity, and GPx antioxidant activity together with lower levels of oxidative damage. In conclusion, the sexual dimorphism in liver mitochondrial oxidative capacity was unaffected by CR, with females showing higher mitochondrial functionality and ROS protection than males.

oxidative phosphorylation; free radicals; antioxidant enzymes; mitochondrial transcription factor A