Fatty acid-binding protein 3 (heart-type) (FABP3)

Fatty acid-binding protein 3 (FABP3), also known as heart-type fatty acid-binding protein, is a small cytosolic protein involved in the uptake, transport, and metabolism of long-chain fatty acids and other lipophilic substances within cells. It is highly expressed in heart and skeletal muscle, where it plays critical roles in energy metabolism by facilitating fatty acid delivery for oxidation and energy production. FABP3 is structurally characterized by a 10-stranded beta-barrel with a central binding pocket for hydrophobic ligands. Beyond its canonical role in lipid handling, FABP3 can influence cellular signaling, gene expression, and growth regulation, including modulation of dopamine receptor signaling in the brain. Loss of FABP3 function in animal models leads to impaired fatty acid metabolism in cardiac and muscle tissue and altered glucose homeostasis. Clinically, FABP3 is a sensitive biomarker for early detection of myocardial injury, as it is rapidly released into the bloodstream upon heart muscle damage. There is emerging but limited evidence linking FABP3 modulation to cancer, metabolic, and neuropsychiatric diseases. FABP3 interacts with some small molecules, notably endocannabinoids and cannabinoids, which inhibit its function and affect endocannabinoid system physiology. While not a direct therapeutic target, its significance as a diagnostic biomarker and its pivotal role in heart and muscle energy homeostasis make it an important molecular target in biomedical research.

Other names

Heart-type fatty acid-binding proteinMammary-derived growth inhibitorMuscle fatty acid-binding proteinMDGIH-FABPM-FABPO-FABPFABP11Fatty acid-binding protein, heartEpididymis secretory sperm binding protein

Inhibition of fatty acid transport/metabolism (THC, CBD inhibit FABP-mediated transport of endocannabinoids) Modulation of nuclear transcription/activity (ligand transport to nuclear receptors, e.g., PPARs)