RESEARCH MONOGRAPH · KDC-MN-373
R-Alpha-Lipoic Acid (R-ALA)
R-alpha-lipoic acid (R-ALA) is the natural form of alpha-lipoic acid, a small molecule mitochondria use as a cofactor in three energy-generating enzymes. The R version is what your cells actually make and recognize; the racemic ALA sold as a generic supplement is half inactive S-form filler. Pharmacologically, R-ALA cycles between oxidized and reduced states, scavenging multiple reactive oxygen species in the process. Approved in Germany and several European countries for diabetic nerve pain (Thioctacid), used as a supplement elsewhere. Plasma half-life is short (about 30 minutes), but peak concentrations are higher with R-ALA than with racemic at the same dose. Standard reference compound for mitochondrial-cofactor antioxidant work. Not stocked by Kodiac. This monograph is provided for research and educational reference.
Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.
Mitochondrial cofactor / antioxidant (R-enantiomer)
The R-enantiomer of alpha-lipoic acid; the naturally occurring form with mitochondrial cofactor and antioxidant activity.
Abstract
R-alpha-lipoic acid (R-ALA, (R)-thioctic acid; CAS 1200-22-2; molecular formula C8H14O2S2; molecular weight 206.32) is the R-enantiomer of alpha-lipoic acid, the form naturally synthesized in mammalian mitochondria from octanoic acid and cysteine. The compound is a mitochondrial cofactor for pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and branched-chain alpha-keto acid dehydrogenase. The R-enantiomer is preferentially recognized by these enzymes; racemic ALA preparations contain 50 percent inactive S-ALA. Pharmacologically, R-ALA is a redox-active compound functioning as both reduced (dihydrolipoic acid) and oxidized forms; the redox cycle scavenges multiple reactive oxygen species. Approved in Germany and other European countries for diabetic peripheral neuropathy (Thioctacid); used in many countries as a supplement. Plasma half-life is short (approximately 30 minutes); peak concentrations are higher with R-ALA versus racemic ALA at equimolar doses. Used as the canonical mitochondrial cofactor antioxidant.
Mechanism of action
Mitochondrial cofactor for keto acid dehydrogenases; redox-active antioxidant. R-enantiomer is the natural form preferentially recognized by metabolic enzymes.
Reported research dose ranges
Supplement 100 to 600 mg in the published literature.
References
- Packer L, et al. Alpha-lipoic acid as a biological antioxidant. Free Radic Biol Med 1995.
- Ziegler D, et al. Treatment of symptomatic diabetic peripheral neuropathy with the antioxidant alpha-lipoic acid. Diabetologia 1995.
- Hermann R, et al. Enantioselective pharmacokinetics and bioavailability of different racemic alpha-lipoic acid formulations. Eur J Pharm Sci 1996.
Read the full monograph
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The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.
FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.