Acetyl-L-carnitine (ALCAR)

Acetyl-L-carnitine (ALCAR) is an endogenous, acetylated derivative of the amino acid L-carnitine that plays a vital role in cellular energy metabolism and neuroprotection [4, 6]. It is synthesized within mitochondria, where it serves as a substrate for the enzyme carnitine O-acetyltransferase (CRAT) to facilitate the reversible transfer of acetyl groups, thereby maintaining mitochondrial acetyl-CoA homeostasis and supporting the transport of fatty acids for beta-oxidation [11, 16]. Beyond its primary metabolic function, ALCAR provides essential acetyl groups for the biosynthesis of the neurotransmitter acetylcholine and exerts neuroprotective and analgesic effects through the epigenetic modulation of histone acetylation [4, 15]. Clinically, ALCAR is utilized as both a drug and a dietary supplement to treat conditions such as diabetic neuropathy, age-related cognitive decline, and geriatric depression [10, 13]. While generally well-tolerated, exogenous administration can cause side effects like gastrointestinal upset or a fishy body odor and requires caution in patients taking anticoagulants like warfarin or those with a history of seizures [10, 11].

Other names

ALCLevacecarnineO-acetyl-L-carnitineAcetylcarnitine

Acetyl-L-carnitine primarily acts as a substrate for carnitine O-acetyltransferase (CRAT), facilitating the transport of acetyl groups across mitochondrial membranes to maintain the acetyl-CoA pool and support fatty acid beta-oxidation. It also serves as an acetyl donor for the synthesis of acetylcholine and mediates neuroprotective effects through antioxidant activity and epigenetic regulation of gene expression, such as the upregulation of metabotropic glutamate receptors.