The Murky Side of Alpha-Lipoic Acid

Here are two more articles showing inhibition of the overall activity and of various components of the pyruvate dehydrogenase complex (PDHC) by lipoic acid enantiomers. I know this can have antioxidant effects under some circumstances, but it doesn't sound all that good to me:

Hong et al., 1999: (http://www.ncbi.nlm.nih.gov/pubmed/10218658)

Korotchkina et al., 2004: (http://www.ncbi.nlm.nih.gov/pubmed/15512796)

These are articles that discuss the "shadowy," "murky" side of alpha-lipoic acid.

Here's an article saying lipoic acid (at very high doses, I'm sure, but still) can cause coenzyme A sequestration (as lipoyl-CoA) and all the effects one would expect from that (thiamine doesn't form CoA esters). That probably wouldn't happen at reasonable doses, but...this doesn't look terrific to me:

http://dmd.aspetjournals.org/cgi/content/abstract/24/6/682 (Gregus et al., 1996)

That last article is bizarre, too, because lipoic acid is a cofactor of the glycine cleavage system, and it's presented as if it activates the glycine cleavage system. Even if it does, this lipoyl-CoA formation could, at high doses of lipoic acid, oppose that effect.