Human Bioavailability and Pharmacokinetic Profile of Different Formulations Delivering Alpha Lipoic Acid

ALA exhibits this activity in both the reduced and oxidated forms. Lipoic acid is a racemic mixture. The redox couple α-lipoic/dihydrolipoic acid containing the R-enantiomer is covalently bound to a lysine residue, forming an essential lipoamide, which functions as a co-enzyme for the E2 subunit of four multi-enzymatic mitochondrial complexes, for example pyruvate dehydrogenase [1-6]. After administration, ALA is reduced at the intracellular level by various enzymes and released into the extracellular environment as its principal metabolite, dihydrolipoic acid (DHLA) [7,8].