Feeding acetyl-L-carnitine and lipoic acid to old rats significantly improves metabolic function while decreasing oxidative stress.
Level 5 - mechanism / opinion, no new human data
Animal research with no human clinical data
PubMed 11854487 · doi:10.1073/pnas.261708898
What was done
Young (2–4 months) and old (24–28 months) F344 rats were supplemented with acetyl-L-carnitine (ALCAR, 1.5% wt/vol in drinking water), (R)-alpha-lipoic acid (LA, 0.5% wt/wt in chow), or both for up to 1 month before death. Researchers measured ambulatory activity, and following hepatocyte isolation, assessed mitochondrial membrane potential, hepatocellular oxygen consumption, ascorbic acid levels, and lipid peroxidation (malondialdehyde).
What was found
ALCAR+LA partially reversed age-related loss of mitochondrial membrane potential and significantly increased hepatocellular O2 consumption (P = 0.02). Ambulatory activity increased in both age groups, with significantly greater improvement in old versus young rats (P = 0.03) and compared to old rats fed either supplement alone. Hepatocellular ascorbate, which was significantly lower in old rats (P = 0.003), was restored to young control levels. Malondialdehyde levels, significantly elevated in old rats (P = 0.0001), were reduced to levels not significantly different from unsupplemented young rats. Absolute numerical values were not reported in the abstract.
Why it matters
This study provides preclinical proof of concept that co-administering a mitochondrial substrate with a mitochondrial antioxidant can synergistically improve cellular energetics and reduce oxidative stress markers in aged animals.
Limits
Findings are limited to an animal model (rats) and isolated hepatocytes, precluding direct inference to human clinical outcomes. The abstract does not report the total sample size (n), exact baseline or post-treatment numerical quantities, or methods regarding randomization and blinding.
Cited by
- supports Research from Bruce Ames' lab showed that the combination of L-carnitine and alpha-lipoic acid improves mitochondrial health.