Alpha Lipoic Acid (ALA)

Alpha Lipoic Acid (ALA)

Summary on Alpha Lipoic Acid (ALA)

  • Healthy young humans can synthesise Alpha Lipoic Acid, however the synthesis declines with age, leading to endothelial dysfunction.
  • α-lipoic acid scavenges reactive oxygen species and enhance endogenous antioxidants like glutathione and vitamins C and E.

Key Studies on Alpha Lipoic Acid (ALA)

  • A recent study was undertaken to investigate the protective effects of two antioxidants, namely, quercetin and ALA in aluminium chloride (AlCl3) induced neurotoxicity in rat brains.
  • AlCl3 induced lipid peroxidation- an important factor for oxidative stress. Quercetin and ALA acting as a free radical scavenger may contribute to the reduction in the peroxidation of lipids. ALA has been shown to protect hippocampus against oxidative stress, by inhibiting the oxidation of lipids and protein. (R1)
  • AlCl3 treatment caused oxidative stress and hence a decreased level in reduced glutathione concentration. Studies of Farr et al., 2012 (R2), have demonstrated that alpha lipoic acid significantly improves reduced glutathione in the mice and reduces lipid peroxidation, suggesting a reversal of oxidative stress.
  • AlCl3 was found to significantly inhibit superoxide dismutase activity in rat brain. Quercetin and lipoic acid pretreatment of AlCl3 exposed rats restored the altered superoxide dismutase to normal levels.
  • AlCl3 was shown to increase acetylcholine esterase activity from the study. Quercetin and lipoic acid caused significant reduction in acetylcholine esterase activity in the brain of AlCl3 treated rats. In vitro, Quercetin has been shown to exhibit acetylcholine esterase inhibitory activity. (R3) These results strongly pronounce the anti-oxidant characteristic of ALA in response to oxidative stress and glutathione depletion.


  • R1. Souza, G. F.; Saldanha, G. B.; Freitas, R. M., Lipoic acid increases glutathione peroxidase, Na+, K+-ATPase and acetylcholinesterase activities in rat hippocampus after pilocarpine-induced seizures? Arquivos de neuro-psiquiatria 2010, 68 (4), 586-91.
  • R2. Farr, S. A.; Price, T. O.; Banks, W. A.; Ercal, N.; Morley, J. E., Effect of alpha-lipoic acid on memory, oxidation, and lifespan in SAMP8 mice. Journal of Alzheimer’s disease : JAD 2012, 32 (2), 447-55.
  • R3. Ademosun, A. O.; Oboh, G.; Bello, F.; Ayeni, P. O., Antioxidative Properties and Effect of Quercetin and Its Glycosylated Form (Rutin) on Acetylcholinesterase and Butyrylcholinesterase Activities. Journal of evidence-based complementary & alternative medicine 2016, 21 (4), NP11-7