Age and gender dependent bioavailability of R- and R,S-α-lipoic acid: A pilot study

Abstract

Lipoic acid (LA) shows promise as a beneficial micronutrient toward improving elder health. Studies using old rats show that (R)-α-LA (R-LA) significantly increases low molecular weight antioxidants that otherwise decline with age. Despite this rationale for benefiting human health, little is known about age-associated alterations in absorption characteristics of LA, or whether the commercially available racemic mixture of LA (R,S-LA) is equally as bioavailable as the naturally occurring R-enantiomer. To address these discrepancies, a pilot study was performed to establish which form of LA is most effectively absorbed in older subjects relative to young volunteers. Young adults (average age = 32 years) and older adults (average age = 79 years) each received 500 mg of either R- or R,S-LA. Blood samples were collected for 3 h after supplementation. After a washout period they were given the other chiral form of LA not originally ingested. Results showed that 2 out of 6 elder males exhibited greater maximal plasma LA and area under the curve for the R-form of LA versus the racemic mixture. The elder subjects also demonstrated a reduced time to reach maximal plasma LA concentration following R-LA supplementation than for the racemic mixture. In contrast, young males had a tendency for increased bioavailability of R,S-LA. Overall, bioavailability for either LA isoform was much more variable between older subjects compared to young adults. Plasma glutathione levels were not altered during the sampling period. Thus subject age, and potential for varied response, should be considered when determining an LA supplementation regimen.

Lipoic acid entrains the hepatic circadian clock and lipid metabolic proteins that have been desynchronized with advanced age

“…These findings reveal the potential of the naturally occurring dithiol compound, LA, which is readily bioavailable [38], to correct circadian rhythms, which have become dysregulated with age. LA may thus be added to the pharmacopeia of compounds (e.g.…”

Epigenetic Treatment of Neurodegenerative Disorders: Alzheimer and Parkinson Diseases

“…a-Lipoic acid [Gora˛ca et al, 2011;Keith et al, 2012] and butyrate have poor pharmacokinetic properties (short half-lives and first-pass hepatic clearance), and the multigram doses needed to achieve therapeutic concentrations in vivo , even if tolerable, are not feasible to administer. The carnitinoids PMX-500FI, PMX500DBr, PMX-550B, and PMX-550DBr overcome these deficiencies.…”

Quantification of lipoic acid from skin samples by HPLC using ultraviolet, electrochemical and evaporative light scattering detectors

“…The following methods have been used for the quantification of LA. (i) Fluorescence detection in a study of supplementation of LA to old and young volunteers [14]. But this method needs a derivatization procedure, which is laborious.…”