The effect of aging and acetyl-L-carnitine on the pyruvate transport and oxidation in rat heart mitochondria.
The effect of aging and acute treatment with acetyl-L-carnitine on the pyruvate transport and oxidation in rat heart mitochondria was studied. The activity of the pyruvate carrier as well as the rates of pyruvate-supported respiration were both depressed (around 40%) in heart mitochondria from aged rats, the major decrease occurring during the second year of life. Administration of acetyl-L-carnitine to aged rats almost completely restored the rates of these metabolic functions to the level of young control rats. This effect of acetyl-L-carnitine was not due to changes in the content of pyruvate carrier molecules. The heart mitochondrial content of cardiolipin, a key phospholipid necessary for mitochondrial substrate transport, was markedly reduced (approximately 40%) in aged rats. Treatment of aged rats with acetyl-L-carnitine reversed the age-associated decline in cardiolipin content. As the changes in cardiolipin content were correlated with changes in rates of pyruvate transport and oxidation, it is suggested that acetyl-L-carnitine reverses the age-related decrement in the mitochondrial pyruvate metabolism by restoring the normal cardiolipin content.
Paradies
G
G
Department of Biochemistry and Molecular Biology, University of Bari, Italy. g.paradies@biologia.uniba.it
Petrosillo
G
G
Gadaleta
M N
MN
Ruggiero
F M
FM
D000108:Acetylcarnitine / Q000494:pharmacology*; D000375:Aging / Q000378:metabolism*; D000818:Animals; D008297:Male; D008929:Mitochondria, Heart / Q000187:drug effects / Q000502:physiology*; D018697:Nootropic Agents / Q000494:pharmacology*; D010084:Oxidation-Reduction; D019289:Pyruvic Acid / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D018697:Nootropic Agents; D000108:Acetylcarnitine; D019289:Pyruvic Acid