In vitro effects of vitamin C, thioctic acid and dihydrolipoic acid on the cytotoxicity of post-ethanol serum.

The serum of subjects consuming ethanol contains a non-dialysable cytotoxic activity, which is thought to reside in unstable acetaldehyde-protein adducts: the cytotoxic effects have been attributed to the transfer of acetaldehyde molecules from such adducts to target cells. When post-alcohol sera are incubated for 3 hr with ascorbic acid, thioctic acid or dihydrolipoic acid at a concentration of 10-500 micrograms/mL, their cytotoxicity against A9 cells is reduced. Post-alcohol sera incubated with these concentrations of thioctic acid or dihydrolipoic acid also had reduced cytotoxic activity against phytohaemagglutinin-transformed normal human lymphocytes. Studies with artificially produced 14C]acetaldehyde-125I-albumin complexes showed that treatment with thioctic acid or dihydrolipoic acid resulted in a reduced transfer of 14C]acetaldehyde to K562 cells. If these in vitro data also apply in vivo and if circulating acetaldehyde-protein adducts play a role in alcohol-mediated tissue damage, vitamin C and, to a greater extent, thioctic acid may have a beneficial effect in patients with acute and chronic alcohol toxicity.