Description | L- Palmitoylcarnitine is a long-chain acyl fatty acid derivative ester of carnitine which facilitates the transfer of long-chain fatty acids from cytoplasm into mitochondria during the oxidation of fatty acids. L-
palmitoylcarnitine, due to its amphipatic character is, like detergents, a surface-active molecule and by changing the membrane fluidity and surface charge can change activity of several enzymes and transporters localized in the membrane. L-palmitoylcarnitine has been also reported to change the activity of certain proteins. On the contrary to carnitine, palmitoylcarnitine was shown to stimulate the activity of caspases 3, 7 and 8 and the level of this long-chain acylcarnitine increased during apoptosis. Palmitoylcarnitine was also reported to diminish completely binding of phorbol esters, the protein kinase C activators and to decrease the autophosphorylation of the enzyme. Apart from these isoform nonspecific phenomena, palmitoylcarnitine was also shown to be responsible for retardation in cytoplasm of protein kinase C isoforms β and δ and, in the case of the latter one, to decrease its interaction with GAP-43.
Some of the physico-chemical properties of palmitoylcarnitine may help to explain the need for coenzyme A-carnitine-coenzyme A acyl exchange during mitochondrial fatty acid import. The amphiphilic character of palmitoylcarnitine may also explain its proposed involvement in the pathogenesis of myocardial ischemia.
L-Palmitoylcarnitine accumulates in ischemic myocardium and potentially contribute to myocardial damage through alterations in membrane molecular dynamics , one mechanism through which could play an important role in ischemic injury. Palmitoylcarnitine is characteristically elevated in carnitine palmitoyltransferase II deficiency, late-onset (OMIM 255110). (PMID 2540838, 15363641, 8706815)
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