title: Food restriction affects energy metabolism in rat liver mitochondria.
abstract: To examine the effect of 50% food restriction over a period of 3 days on mitochondrial energy metabolism, liver mitochondria were isolated from ad libitum and food-restricted rats. Mitochondrial enzyme activities and oxygen consumption were assessed spectrophotometrically and polarographically. With regard to body weight loss (-5%), food restriction decreased the liver to body mass ratio by 7%. Moreover, in food-restricted rats, liver mitochondria displayed diminished state 3 (-30%), state 4-oligomycin (-26%) and uncoupled state (-24%) respiration rates in the presence of succinate. Furthermore, "top-down" elasticity showed that these decreases were due to an inactivation of reactions involved in substrate oxidation. Therefore, it appears that rats not only adapt to food restriction through simple passive mechanisms, such as liver mass loss, but also through decreased mitochondrial energetic metabolism.
authors.affiliation: INSERM EMI-U 00.18, Laboratoire de Biochimie et de Biologie Moléculaire, Medecine B, CHU, F-49033 Angers Cedex 01, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Dumas
authors.forename: Damien
authors.initials: D
authors.lastname: Roussel
authors.forename: Gilles
authors.initials: G
authors.lastname: Simard
authors.forename: Olivier
authors.initials: O
authors.lastname: Douay
authors.forename: Françoise
authors.initials: F
authors.lastname: Foussard
authors.forename: Yves
authors.initials: Y
authors.lastname: Malthiery
authors.forename: Patrick
authors.initials: P
authors.lastname: Ritz
mesh_terms: D000818:Animals; D001835:Body Weight; D002950:Citrate (si)-Synthase / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D004734:Energy Metabolism; D005508:Food Deprivation / Q000502:physiology*; D008564:Membrane Potentials; D008930:Mitochondria, Liver / Q000201:enzymology / Q000378:metabolism*; D009840:Oligomycins; D009929:Organ Size; D010089:Oxidoreductases, N-Demethylating / Q000378:metabolism; D010101:Oxygen Consumption; D051381:Rats; D017207:Rats, Sprague-Dawley; D019802:Succinic Acid / Q000378:metabolism; D013997:Time Factors
chemical_list: D009840:Oligomycins; D019802:Succinic Acid; D010089:Oxidoreductases, N-Demethylating; C022726:tetramethylphenylenediamine oxidase; D003576:Electron Transport Complex IV; D002950:Citrate (si)-Synthase