Prolonged effect of single carnitine administration on fasted carnitine-deficient JVS mice regarding their locomotor activity and energy expenditure.
Carnitine is an essential cofactor for the oxidation of fatty acid in the mitochondria and an efficient therapeutics for primary carnitine deficiency. We herein analyzed the prolonged effects of carnitine on the reduced locomotor activity and energy metabolism of fasted carnitine-deficient juvenile visceral steatosis (jvs(-/-)) mice. We found that a single carnitine administration to 24-h fasted jvs(-/-) mice in the morning increased both the locomotor activity and oxygen consumption at night not only on the same day, but also on the next day, when the carnitine levels in the blood and tissues were already as low as at the original carnitine-deficient state. We also found that fat utilization for energy production significantly increased under fasting even in jvs(-/-) mice and was stimulated in the carnitine-administrated fasted jvs(-/-) mice at night, in comparison to that observed in the saline-administered jvs(-/-) mice, at least for 2 days even under the low plasma and tissue carnitine levels. These results suggest that the low tissue carnitine levels are therefore not the sole rate-limiting factor of general fatty acid oxidation in carnitine-deficient jvs(-/-) mice.
Li
Meng Xian
MX
Department of Molecular Metabolism and Biochemical Genetics, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan.
Yoshida
Goichiro
G
Horiuchi
Masahisa
M
Kobayashi
Keiko
K
Saheki
Takeyori
T
D000818:Animals; D002331:Carnitine / Q000172:deficiency* / Q000494:pharmacology*; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000187:drug effects*; D005215:Fasting / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D009043:Motor Activity / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010084:Oxidation-Reduction; D012202:Reye Syndrome / Q000378:metabolism
D005227:Fatty Acids; D002331:Carnitine