hydroxybutyrate
Hydroxybutyrate is a term that can refer to any hydroxy-substituted butyrate, but in physiology it most commonly denotes beta-hydroxybutyrate (β-hydroxybutyrate, BHB), a ketone body produced in the liver during fasting or carbohydrate-restricted states. The term can also refer to gamma-hydroxybutyrate (GHB), a distinct compound with sedative properties and abuse potential. BHB occurs as two enantiomers, D-β-hydroxybutyrate and L-β-hydroxybutyrate; the D form is the primary energy-carrying ketone produced in humans.
During fasting or ketogenic diet, fatty acids are oxidized in the liver to acetyl-CoA, which is converted
β-hydroxybutyrate serves as an important energy substrate for the brain, heart, and skeletal muscle during prolonged
Clinically, blood levels of ketone bodies, including β-hydroxybutyrate, are measured to assess ketosis or metabolic state;