Age-Related Changes in Activities of Mitochondrial Electron Transport Complexes in Various Tissues of the Mouse

doi:10.1006/abbi.1999.1495

Archives of Biochemistry and Biophysics

Volume 373, Issue 1, 1 January 2000, Pages 16-22

https://doi.org/10.1006/abbi.1999.1495 Get rights and content

Abstract

The purpose of the present study was to examine the role of mitochondria in the aging process by determining whether the activities of various electron transport chain oxidoreductases are deleteriously affected during aging and whether the hypothesized age-related alterations in different tissues follow a common pattern. Activities of respiratory complexes I, II, III, and IV were measured in mitochondria isolated from brain, heart, skeletal muscle, liver, and kidney of young (3.5 months), adult (12–14 months), and old (28–30 months) C57BL/6 mice. Activities of some individual complexes were decreased in old animals, but no common pattern can be discerned among various tissues. In general, activities of the complexes were more adversely affected in tissues such as brain, heart, and skeletal muscle, whose parenchyma is composed of postmitotic cells, than those in the liver and kidney, which are composed of slowly dividing cells. The main feature of age-related potentially dysfunctional alterations in tissues was the development of a shift in activity ratios among different complexes, such that it would tend to hinder the ability of mitochondria to effectively transfer electrons down the respiratory chain and thus adversely affect oxidative phosphorylation and/or autooxidizability of the respiratory components.

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^☆: This research was supported by Grants R01 AG7657 and R01AG13564 from the National Institutes of Health - National Institute on Aging.

²: To whom correspondence and reprint requests should be addressed. Fax: (214) 768-3955. E-mail: [email protected].

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Regular ArticleAge-Related Changes in Activities of Mitochondrial Electron Transport Complexes in Various Tissues of the Mouse☆

Abstract

Free Rad. Biol. Med.

Brain Res.

Mech. Ageing Dev.

Biochim. Biophys. Acta

Biochem. Mol. Med.

J. Neur. Sci.

Biochem. Biophys. Res. Commun.

Eur. J. Pharmacol.

Arch. Biochem. Biophys.

Brain Res.

Trends Genet.

Arch. Biochem. Biophys.

Biochem. Biophys. Res. Commun.

Exp. Mol. Pathol.

Free. Rad. Biol. Med.

Methods Enzymol.

Neurobiol. Aging

Free Rad. Biol. Med.

Biochim. Biophys. Acta

Pharmacol. Res.

Biochim. Biophys. Acta

Regular Article
Age-Related Changes in Activities of Mitochondrial Electron Transport Complexes in Various Tissues of the Mouse☆