Differential activity of lipoic acid enantiomers in cell culture.
It is unclear whether the two enantiomeric forms (R & S) of lipoic acid (LA) share similar pharmacological activity and the exact cellular targets of LA are not well identified. We oxidatively stressed 3 cell culture systems representing different cell types. Mitochondrial metabolism was the primary endpoint. When C6 glioma was damaged by hydrogen peroxide (H2O2), all forms of LA protected. Racemic and S-LA were less effective than the R-isomer that was also protective in tertiary butyl hydroperoxide (TBHP)-damaged C6 glioma. In PC12 cells, little damage was produced by TBHP; R-LA increased mitochondrial metabolism above the level of non-damaged control. In H2O2 damaged PC12 cells, R-LA and racemic LA (but not S-LA) not only protected against damage, but increased mitochondrial metabolism above the non-damaged control level. When BAE cells were damaged with H2O2, R- and racemic LA protected while S-LA was ineffective.
Smith
Jerry Robert
JR
Department of Biomedical and Pharmaceutical Sciences, College of Health and Biomedical Sciences, #32 Campus Drive 1552, Missoula, MT, 59812-1552, USA. Jerry.smith@umontana.edu
Thiagaraj
Harish V
HV
Seaver
Benjamin
B
Parker
Keith K
KK
D000818:Animals; D016587:Antimutagenic Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D001254:Astrocytoma / Q000378:metabolism; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D008928:Mitochondria / Q000378:metabolism*; D010673:Pheochromocytoma / Q000378:metabolism; D051381:Rats; D013237:Stereoisomerism; D008063:Thioctic Acid / Q000737:chemistry* / Q000494:pharmacology*
D016587:Antimutagenic Agents; D000975:Antioxidants; D008063:Thioctic Acid