Free L-carnitine

L-carnitine is formed endogenously from lysine and methionine in the cells of the of the liver, kidneys and brain, and is supplied to the body with food, mainly beef and dairy. L-carnitine is involved involved in lipid metabolism by transporting long-chain fatty acids into the mitochondria, and also participates in the the conversion of acetyl-coenzymeA (acetyl-CoA) to acetylcarnitine and Coenzyme A (CoA), thereby increasing the availability of CoA needed for the oxidative decarboxylation of pyruvate in the Krebs cycle. W nervous system, acetylcarnitine is a donor of acetyl groups necessary for the formation of acetylcholine. L-carnitine also has antioxidant activity. In the body, L-carnitine occurs in the free form or as esters of L-acetylcarnitine and L-propionylcarnitine. L-carnitine determination is performed in cases of suspected primary or secondary deficiencies.