D-beta-hydroxybutyrate (BHB)

D-beta-hydroxybutyrate is the most abundant physiological ketone body produced in the liver during periods of low carbohydrate availability, such as fasting, prolonged exercise, or ketogenic diets. It serves as an alternative energy source for peripheral tissues and the brain, particularly when glucose is scarce. In addition to its metabolic role, BHB also functions as a signaling molecule: it is a ligand for hydroxycarboxylic acid receptor 2 (HCAR2, also known as niacin receptor 1), acts as an endogenous inhibitor of certain histone deacetylases (HDACs), modulates inflammation (sometimes anti-inflammatory, sometimes pro-inflammatory), and has been implicated in the regulation of oxidative stress and apoptosis pathways. BHB is being investigated for therapeutic potential in a range of diseases, including neurodegenerative, metabolic, cardiovascular, and some cancers. However, D-beta-hydroxybutyrate itself is a small metabolite rather than a receptor, enzyme, or typical drug target. It is a ligand (i.e., binds to or modulates targets such as HCAR2), but is not in itself a receptor, transporter, or enzyme target. Therefore, its classification as a "therapeutic target" is incorrect, but it is an important endogenous molecule and biomarker with pharmacological significance[2][4][6][7][8][10][12].

Other names

D-β-hydroxybutyrate(R)-3-hydroxybutyric acidD-3-hydroxybutyrate3-hydroxybutyric acidD-(-)-beta-hydroxybutyric acid