Ketone body synthesis is a metabolic pathway occurring primarily in hepatocytes that converts acetyl-CoA into ketone bodies (acetoacetate, beta-hydroxybutyrate, and acetone) to serve as alternative fuel sources when glucose metabolism is impaired. This process is strictly regulated by the depletion of oxaloacetate via gluconeogenesis during starvation or diabetic ketoacidosis, which inhibits the TCA cycle and electron transport chain, necessitating exogenous energy substrates; it also occurs in chronic alcoholism due to an increased NADH/NAD+ ratio preventing oxaloacetate regeneration. The pathway is catalyzed by specific enzymes including HMG-CoA synthase (rate-limiting) and acetoacetyl-CoA thiolase, operating under the physiological constraint that glucose availability must be insufficient or inaccessible for alternative fuels to become primary energy sources.
Ketone body synthesis is a metabolic pathway occurring primarily in hepatocytes that converts acetyl-CoA into ketone bodies (acetoacetate, beta-hydroxybutyrate, and acetone) to serve as alternative f…