Ketone bodies are water-soluble equivalents of fatty acids. They can substitute for glucose when glucose becomes limited in physiological and pathological states.
Keywords: ketone bodies; malonyl-CoA; ketoacidosis
Ketone Bodies
Beatrice Morio, Unité Métabolismes Protéique et Energétique, Clermont‐Ferrand, France
Robert R Wolfe, University of Texas Medical Branch, Galveston, TX, USA
Published online: September 2005
DOI: 10.1038/npg.els.0003819
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Figure 1. The synthesis of acetoacetate and d--hydroxybutyrate from acetyl-CoA in the liver mitochondria.
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Figure 2. The metabolic conversion of d--hydroxybutyrate and acetoacetate to acetyl-CoA in the mitochondria of peripheral tissues.
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Figure 3. Inhibition of the glycolytic pathway by ketone body oxidation. Oxidation of ketone bodies causes acetyl-CoA and NADH to increase in the mitochondria, thereby inhibiting pyruvate dehydrogenase activity, and thus pyruvate oxidation. As part of the feedback loop, the glycolytic pathway is ultimately inhibited by an increased concentration of citrate and glycolytic intermediates.
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| Further Reading | |
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Control of mitochondrial -oxidation: sensitivity of the trifunctional protein to [NAD | |
| Freeman JB, Stegink LD, Fry LK, Sherman BM and Denbesten L (1975) Evaluation of amino acid infusions as protein-sparing agents in normal adult subjects. American Journal of Clinical Nutrition 28(5): 477–481. | |
| Ikeda T, Yoshida T, Ito Y et al. (1987) Effect of beta-hydroxybutyrate and acetoacetate on insulin and glucagon secretion from perfused rat pancreas. Archives of Biochemistry and Biophysics 257(1): 140–143. | |
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| Thompson JR and Wu G (1991) The effect of ketone bodies on nitrogen metabolism in skeletal muscle. Comparative Biochemistry and Physiology. B, Comparative Biochemistry 100(2): 209–216. | |
| Wicklmayr M, Rett K, Dietze G and Mehnert H (1986) Inhibition of muscular triglyceride lipolysis by ketone bodies: a mechanism for energy-preservation in starvation. Hormone and Metabolic Research 18(7): 476–478. | |
