title: Silvering and swimming effects on aerobic metabolism and reactive oxygen species in the European eel.
abstract: Silvering, the last metamorphosis in the eel life cycle induces morphological and physiological modifications in yellow eels (sedentary stage). It pre-adapts them to cope with the extreme conditions they will encounter during their 6000-km spawning migration. A previous study showed that silver eels are able to cope with reactive oxygen species (ROS) over-production linked to an increase in aerobic metabolism during sustained swimming, but the question remains as to whether this mechanism is associated with silvering. A sustained swimming session decreased red muscle in vitro mitochondrial oxygen consumption (MO2) but increased ROS production in both eel stages. The swimming exercise used here was perhaps too intense to induce a stimulation of mitochondrial function or biogenesis even when antioxidant enzyme activities were unchanged. Pro-oxidant/antioxidant imbalance by lipid peroxidation increased in yellow but significantly decreased in silver eels. The silvering process therefore appears to allow a pre-adaptation of red muscle radical metabolism to the demands of spawning migration.
authors.affiliation: EA4324 ORPHY, Université de Bretagne Occidentale, IBSAM, UFR Sciences et Techniques, France. Electronic address: aline.amerand@univ-brest.fr.
authors.forename: Aline
authors.initials: A
authors.lastname: Amérand
authors.affiliation: EA4324 ORPHY, Université de Bretagne Occidentale, IBSAM, UFR Sciences et Techniques, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Mortelette
authors.affiliation: EA4324 ORPHY, Université de Bretagne Occidentale, IBSAM, UFR Sciences et Techniques, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Belhomme
authors.affiliation: EA4324 ORPHY, Université de Bretagne Occidentale, IBSAM, UFR Sciences et Techniques, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Moisan
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002950:Citrate (si)-Synthase / Q000378:metabolism; D004524:Eels / Q000254:growth & development* / Q000378:metabolism*; D005260:Female; D029941:Fish Proteins / Q000378:metabolism; D015227:Lipid Peroxidation; D008315:Malondialdehyde / Q000378:metabolism; D008675:Metamorphosis, Biological / Q000502:physiology*; D008928:Mitochondria / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D010101:Oxygen Consumption / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013550:Swimming / Q000502:physiology*
chemical_list: D000975:Antioxidants; D029941:Fish Proteins; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D002950:Citrate (si)-Synthase
keywords: Eel silvering process; Energy metabolism; Reactive oxygen species; Training protocol