Adenosine monophosphate fatty acid oxidation

Gamble, J. Lopaschuk, G.D. Insulin inhibition of 5 -adenosine monophosphate-activated protein kinase in the heart results in activation of acetyl coenzyme A carboxylase and inhibition of fatty acid oxidation. Metabolism, 46, 1270-1274 (1997)... 

ACC-2 produces malonyl CoA, which inhibits carnitine palmitoyl transferase I, thereby blocking fatty acid entry into the mitochondria. Muscle also contains malonyl CoA decarboxylase, which catalyzes the conversion of malonyl CoA to acetyl CoA and carbon dioxide. Thus, both the synthesis and degradation of malonyl CoA is carefully regulated in muscle cells to balance glucose and fatty acid oxidation. Both allosteric and covalent means of regulation are employed. Citrate activates ACC-2, and phosphorylation of ACC-2 by the adenosine monophosphate (AMP)-activated protein kinase inhibits ACC-2 activity. Phosphorylation of malonyl CoA decarboxylase by the AMP-activated protein kinase activates the enzyme, further enhancing fatty acid oxidation when energy levels are low. 

Maintenance of adrenal cortex Promotes secretion of steroids, oxidative phosphorylation in adrenal cortex Mobilizes and increases oxidation of free fatty acid in adipose tissue Increases gluconeogenesis in liver increases cyclic adenosine monophosphate (AMP) in adrenal cortex Decreases urea formation in liver... 

Muscle glycogen phosphorylase, Uke its counterpart in the Uver, is activated by phosphorylation via phosphorylase kinase. Even in its dephosphorylated state, glycogen phosphorylase is activated aUosterically by adenosine monophosphate (AMP). AMP concentrations rise whenever ATP concentrations faU (Example 13.24), so if the combined effects of both fatty acid and glucose oxidation are unable to sustain normal ATP concentrations in contracting muscle, AMP concentrations rise quickly and stimulate glycogen phosphorylase. 

When sufficient oxygen is available (aerobic conditions), either in muscle tissue or elsewhere, these processes are reversed. ATP is reformed from ADP and AMP (adenosine monophosphate), CP is reformed from creatine and phosphate (P), and glycogen is reformed from glucose or lactic acid. Energy for these processes is derived from the complete oxidation of carbohydrates, fatty acids, or amino acids to form carbon dioxide and water. These reactions can be summarized by the following equations ... 

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