Ketone bodies utilization

Patel, M. S., Johnson, C. A., Rajan, R. etal. The metabolism of ketone bodies in developing human brain development of ketone-body-utilizing enzymes and ketone bodies as precursors for lipid synthesis. /. Neurochem. 25 905-908, 1975. 

Ketone body utilization by heart, muscle, kidney 60 0... 

Most tissues switch to either fatty acid or ketone body utilization except the red and white blood cells, retina, and adrenal medulla. Even brain utilizes largely ketone bodies. 

Nehlig, A. and Pereira de Vasconcelos, A, (1993) Glucose and ketone body utilization by the brain of neonatal rats. Progress in Neurobiology. 40. 163-221. 

Hawkins, R.A., Mans, A.M., and Davis, D.W. (1986) Regional ketone body utilization by rat brain in starvation and diabetes. The American Journal of Physiology. 250, E169-E178. 

Metabolized in TCA cycle or used in other metabolic pathways (porphyrin synthesis, ketone body utilization, etc.)... 

Hawkins RA, Williamson DH, Krebs HA. Ketone-body utilization by adult and suckling rat brain in vivo. Biochem J 1971 122 13-18. 

Kraus H, Schlenker S, Schwedesky D. Developmental changes of cerebral ketone body utilization in human infants. Hoppe-Seyler s Zeitschr Physiol Chem 1974 355 164—170. 

B. The synthesis of ketone bodies begins with the combination of two molecules of acetyl-CoA to generate one molecule of free CoA and a molecule of acetoacetyl-CoA, which combines with another molecule of acetyl-CoA to yield another free CoA molecule and P-hydroxy-P-methylglutaryl-CoA (HMG-CoA). HMG-CoA undergoes hydrolysis to produce one molecule acetyl-CoA and one molecule of acetoacetate, which can be reduced to P-hydroxybutyrate. The reaction of succinyl-CoA and acetoacetate is a reaction in the pathway of ketone body utilization but not in the pathway of ketone body formation. 

TCA cycle (acetyl CoA CO2 + H2O) p-OxIdatlon of fatty adds Ketone body formation Ketone body utilization... 

Red blood cells lack mitochondria, 1 which is the site of ketone body utilization. 

C) The energy yield from ketone body utilization is dramatically reduced. 

Linares, A., Caamafio, G.J., Diaz, R, Gonzalez, F.J. Gatda-Pelegrit), E. (1993). Changes in ketone body utilization by chick liver, duodenal mucosa and kidney during emtayonic and postnatal development. Comp. Biochem. Physiol, 105B, 277—82. 

Fig. 2.3 Proposed scheme of the metabohc side of HIF-1 regulation through ketosis. The inhibition of the PHD reaction by an intermediate of energy metabolism, succinate, as a result of ketone body utilization by brain. The relationship of the metabolic pathways of glucose and ketone bodies entering the citric acid cycle and HlF-1 is illustrated. In contrast to glucose metabolism, increased ketone metabolism results in elevated levels of mitochondrial succinate, which is transported out of the mitochondria into the cytosol resulting in the inhibition of PHD and thus stabilization of HIF-1...

Sass JO. Inborn errors of ketogenesis and ketone body utilization. J Inherit Metab Dis. 2012 35(l) 23-8. 

In contrast to peripheral tissue, which can readily oxidize ketone bodies, the liver is poorly equipped for ketone body utilization. Consequently, whenever the production of ketone bodies in liver exceeds the ability of the peripheral tissue to use them, ketosis takes place [134, 135]. 

Ketone body utilization depends on the presence of key enzymes in the tissues ... 

The increased rate of ketone body utilization in starvation is essentially not determined by a raised capacity of the enz3mies of ketone body utilization. By far the most important factor would appear to be the concentration of ketone bodies in the blood. 

In non-ruminant animals, including Man, the liver is the only organ that adds ketone bodies to the blood since its enzymes are active in ketone body production but inactive in ketone body utilization. This is exactly the reverse of the condition in muscle and other extrahepatic tissues which oxidize ketone bodies but do not produce them. 

Ketone body utilization. Carnitine stimulates acetoace-tate oxidation thus, it may play a role in ketone body utilization. 

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