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

Exposure of 3T3 fibroblasts to Fe-II reveals a concentration-dependent inhibition of cell proliferation compared to control cells, the apparent threshold for this iron-mediated effect being 5 mu M Fe-II. 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 Fe-II with varying concentrations of ascorbic acid over the range 5 mu M to 240 mu M 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 Fe-II nor any protective effect of ascorbate when cultures of 3T3 mouse fibroblasts are exposed to co-supplementation regimes of iron with ascorbic acid.