Carnitine O-palmitoyltransferase 2, mitochondrial

CPT2 (Carnitine O-palmitoyltransferase 2, mitochondrial) is a key enzyme catalyzing the intramitochondrial conversion of long- and medium-chain acyl-CoA esters into acylcarnitines, enabling fatty acid β-oxidation within mitochondria (UniProt: P23786). This reversible acylation is essential for mitochondrial uptake and catabolism of lipids, particularly those with carbon chains of 8–18 carbons.

CPT2 is localized to the inner mitochondrial membrane and is involved in cellular energy metabolism. Genetic mutations cause rare autosomal recessive disorders ranging from fatal neonatal presentations (CPT2DLN, MIM 608836) to myopathic stress-induced forms (CPT2D, MIM 255110), all characterized by impaired fatty acid oxidation and recurrent myoglobinuria or hepatoencephalopathy (UniProt: P23786).

CPT2 has been identified as upregulated in Alzheimer's disease brain tissue. Analysis of post-mortem AD brain versus age-matched controls using TMT-labeled proteomics across four subcellular fractions revealed a mean log2 fold-change of 0.96, indicating modest but consistent elevation (Chaparral AD proteomics). This upregulation may reflect altered mitochondrial lipid metabolism or compensatory metabolic responses in AD pathology.