Carnitine shuttle pathway enzymes and transporters

The carnitine shuttle pathway is an essential metabolic system composed of enzymes and transporters that facilitate the import of long-chain fatty acids into the mitochondrial matrix for β-oxidation. The core components include carnitine palmitoyltransferase 1 (CPT1, in the outer mitochondrial membrane), carnitine-acylcarnitine translocase (CACT, encoded by SLC25A20, in the inner mitochondrial membrane), and carnitine palmitoyltransferase 2 (CPT2, in the inner mitochondrial membrane)[1][2][3][6]. Additionally, the plasma membrane transporter OCTN2 (SLC22A5) is responsible for carnitine uptake into cells[3]. Defects in any of these proteins disrupt fatty acid oxidation and energy homeostasis, resulting in metabolic diseases, cardiomyopathy, and muscle weakness. Some pharmacological agents target CPT1 or the carnitine shuttle to manipulate energy metabolism in heart disease or cancer research.

Other names

Carnitine shuttle systemCarnitine transport systemCarnitine palmitoyltransferase system

Inhibition of carnitine palmitoyltransferase 1 (CPT1) to reduce fatty acid oxidation Supplementation with L-carnitine to restore or enhance fatty acid transport