Mass isotopomer study of anaplerosis from propionate in the perfused rat heart.
Anaplerosis from propionate was investigated in rat hearts perfused with 0-2mM [(13)C(3)]propionate and physiological concentrations of glucose, lactate, and pyruvate. The data show that when the concentration of [(13)C(3)]propionate was raised from 0 to 2mM, total anaplerosis increased from 5% to 16% of the turnover of citric acid cycle intermediates. Then, [(13)C(3)]propionate abolished anaplerosis from endogenous substrates, glucose, lactate, and pyruvate. Also, while the contents of propionyl-CoA and methylmalonyl-CoA increased with [(13)C(3)]propionate concentration, the content of succinyl-CoA decreased, presumably via activation of succinyl-CoA hydrolysis by a decrease in free CoA. Under our conditions, [(13)C(3)]propionate was a purely anaplerotic substrate since there was no labeling of mitochondrial acetyl-CoA, reflected by the labeling of the acetyl moiety of citrate.
Kasumov
Takhar
T
Department of Nutrition, Case Western Reserve University, School of Medicine - WG 48, 10900 Euclid Avenue, Cleveland, OH 44106-4954, USA.
Cendrowski
Andrea V
AV
David
France
F
Jobbins
Kathryn A
KA
Anderson
Vernon E
VE
Brunengraber
Henri
H
D000214:Acyl Coenzyme A / Q000378:metabolism; D000818:Animals; D002247:Carbon Isotopes; D002952:Citric Acid Cycle / Q000502:physiology*; D003903:Deuterium; D005947:Glucose / Q000378:metabolism; D066298:In Vitro Techniques; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010477:Perfusion; D011422:Propionates / Q000378:metabolism*; D019289:Pyruvic Acid / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D000214:Acyl Coenzyme A; D002247:Carbon Isotopes; D011422:Propionates; C009061:propionyl-coenzyme A; D019344:Lactic Acid; D019289:Pyruvic Acid; D003903:Deuterium; D005947:Glucose