Regulation of fatty acid oxidation in chicken (Gallus gallus): interactions between genotype and diet composition.
To explore the mechanisms leading to excessive adiposity in chicken, we investigated the regulation of fatty acid oxidation depending on genotype-related body fatness and diet composition. mRNA expression and/or activity of proteins involved in mitochondrial energy metabolism were measured in liver and gastrocnemius muscle of genetically lean or fat chickens reared on a low-fat/high-protein diet or an isoenergetic high-fat/low-protein diet (HF/LP). Muscle expressions of the muscle isoform of carnitine-palmitoyltransferase 1 (M-CPT1) and PPARbeta/delta were higher in fat than in lean chickens. This was also observed in liver, although only with the HF/LP diet for M-CPT1. This could stimulate mitochondrial fatty acid oxidation in fat chickens. Up-regulations of liver and muscle CPT-1 hepatic isoform, and muscle cytochrome-c-oxidase mRNA expressions, and of beta-hydroxyacyl-CoA-dehydrogenase activities suggest higher fatty acid utilization with the HF/LP diet. PPARbeta/delta and PGC-1alpha could control fatty acid oxidation in muscle and liver, respectively. Regulation of avian uncoupling protein (avUCP) mRNA was tissue-dependent. Predominantly expressed in muscle, it was stimulated in fat and in HF/LP-fed chickens, where it could be associated to the special need in muscle anti-oxidant pathways of fatter animals. In liver it was lower in fat than in lean chickens, and its potential function remains to be clarified.
Collin
A
A
INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France. collin@tours.inra.fr
Swennen
Q
Q
Skiba-Cassy
S
S
Buyse
J
J
Chartrin
P
P
Le Bihan-Duval
E
E
Crochet
S
S
Duclos
M J
MJ
Joubert
R
R
Decuypere
E
E
Tesseraud
S
S
D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics / Q000378:metabolism; D002645:Chickens / Q000235:genetics / Q000378:metabolism*; D004032:Diet; D018752:Diet, Fat-Restricted; D018753:Diet, Protein-Restricted; D004734:Energy Metabolism / Q000235:genetics / Q000502:physiology*; D005227:Fatty Acids / Q000378:metabolism*; D005838:Genotype; D050356:Lipid Metabolism / Q000502:physiology; D008297:Male; D008930:Mitochondria, Liver / Q000502:physiology; D024101:Mitochondrial Proteins; D018482:Muscle, Skeletal / Q000502:physiology; D010084:Oxidation-Reduction; D012333:RNA, Messenger / Q000378:metabolism
D005227:Fatty Acids; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D002334:Carnitine O-Palmitoyltransferase