Figure 2: llustration of biochemical interactions: the carnitine shuttle, fatty acid oxidation, and glycolysis. The mitochondrial membrane is not permeable to long-chain fatty acids. The carnitine shuttle has to be used to transfer long-chain fatty acids to the mitochondrial matrix space. Once in the mitochondrial matrix space, long-chain acylcarnitines are converted back to long-chain acyl-coenzyme A derivatives and free carnitine via CPT2. Free carnitine is released and the acyl-coenzyme A derivatives will enter the beta-oxidation pathway. CPT1: Carnitine-Palmitoyltransferase 1; CPT2: Carnitine-Palmitoyltransferase 2; CAT: Carnitine-/Acylcarnitine-Transferase; LC: Long-chain; TCA: Tricarboxylic acid cycle; PC: Pyruvate Carcoxylase; PDH: Pyruvate Dehydrogenase.