Figure 3.

The diamine oxidase inhibitor aminoguanidine prevents FCS-mediated cytotoxic effects of spermine and spermidine. Here, FCS (100%) was preincubated with the indicated concentrations of aminoguanidine (AG) for 24 h. Tenfold dilutions of these samples were then used as cell culture supplement for TZM-bl cells, which were incubated with spermine (a) and spermidine (b) for 2 days. Viability was determined by MTT assay. Data shown are average % values derived from 3 individual experiments performed in biological triplicates ± SD.