Effect of alpha-lipoic acid on 3T3 and 3T3-SV40 fibroblasts: Comparison with N-acetylcysteine

Abstract

In this study, we have investigated the intracellular level of reduced glutathione, cell-cycle phase distribution, and microfilament and microtubule structures in normal (3T3) and transformed (3T3-SV40) fibroblasts exposed to alpha-lipoic acid (ALA) in concentrations of 0.7–5 mM. It was found that ALA treatment increased the glutathione content in transformed cells, but did not affect its level in normal cells; moreover, it also induced the cell-cycle arrest of 3T3 cells (but not 3T3-SV40 cells) and disrupted actin microfilaments in cells of both lines. The ALA effect was compared to that of N-acetylcysteine (NAC), another antioxidant we examined previously. The findings allow us to assert that each of these antioxidants impacts on distinct target molecules in normal and transformed cells and activates different signal and metabolic pathways in these cells. However, intermediate steps of ALA and NAC action may be common (altered intracellular level of glutathione, reorganization of actin cytoskeleton, etc.).