title: Making heads or tails of mitochondrial membranes in longevity and aging: a role for comparative studies.
abstract: Mitochondria play vital roles in metabolic energy transduction, intermediate molecule metabolism, metal ion homeostasis, programmed cell death and regulation of the production of reactive oxygen species. As a result of their broad range of functions, mitochondria have been strongly implicated in aging and longevity. Numerous studies show that aging and decreased lifespan are also associated with high reactive oxygen species production by mitochondria, increased mitochondrial DNA and protein damage, and with changes in the fatty acid composition of mitochondrial membranes. It is possible that the extent of fatty acid unsaturation of the mitochondrial membrane determines susceptibility to lipid oxidative damage and downstream protein and genome toxicity, thereby acting as a determinant of aging and lifespan. Reviewing the vast number of comparative studies on mitochondrial membrane composition, metabolism and lifespan reveals some evidence that lipid unsaturation ratios may correlate with lifespan. However, we caution against simply relating these two traits. They may be correlative but have no functional relation. We discuss an important methodology for body mass and phylogenetic correction in comparative studies.
authors.affiliation: Research Institute of Wildlife Ecology, Veterinary University Vienna, Savoyenstrasse 1, 1160 Vienna, Austria.|Institute of Genetics and Developmental Biology, State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences, Beichen Xi Lu, Chaoyang, Beijing, China.
authors.forename: Teresa G
authors.initials: TG
authors.lastname: Valencak
authors.affiliation: Christ's College & Department of Medicine, University of Cambridge, Cambridge CB2 3BU, UK.
authors.forename: Vian
authors.initials: V
authors.lastname: Azzu