The effects of ascorbic acid and iron co-supplementation on the proliferation of 3T3 fibroblasts.

Exposure of 3T3 fibroblasts to FeII reveals a concentration-dependent inhibition of cell proliferation compared to control cells, the apparent threshold for this iron-mediated effect being 5 microM FeII. The inhibition of cell proliferation was accompanied by an enhancement of total malondialdehyde (MDA) levels (as detected directly by hplc) in the cells at higher iron concentrations. The co-supplementation of FeII with varying concentrations of ascorbic acid over the range 5 microM to 240 microM had no significant effect on the threshold for iron toxicity or lipid peroxidation. These results show that there is neither a significant exacerbation of the pro-oxidant effect of FeII nor any protective effect of ascorbate when cultures of 3T3 mouse fibroblasts are exposed to co-supplementation regimes of iron with ascorbic acid.