Anti-oxidant activity of spermine and spermidine re-evaluated with oxidizing systems involving iron and copper ions

This study was designed to investigate the direction of redox reactions of spermine and spermidine in the presence of iron and copper. The redox activity of spermine and spermidine was assessed using a variety of methods, including their ability to: (1) reduce Fe3+ to Fe2+ ions; (2) protect deoxyribose from oxidation by Fe2+-ethylene diaminetetraacetic acid, Fe3+-ethylene diaminetetraacetic acid systems with and without H2O2; (3) protect DNA from damage caused by Cu2+-H2O2, and Fe2+-H2O2 with and without ascorbic acid; (4) inhibit H2O2-peroxidase-induced luminol dependent chemiluminescence; (5) scavenge diphenyl-picryl-hydrazyl radical. Spermine and spermidine at concentration 1 mM reduced 1.8 ± 0.3 and 2.5 ± 0.1 nmol of Fe3+ ions during 20 min incubation. Both polyamines enhanced deoxyribose oxidation. The highest enhancement of 7.6-fold in deoxyribose degradation was found for combination of spermine with Fe3+-ethylene diaminetetraacetic acid. An 10 mM spermine and spermidine decreased CuSO4-H2O2-ascorbic acid- and FeSO4-H2O2-ascorbic-induced DNA damage by 73 ± 6, 69 ± 4% and 90 ± 5, 53 ± 4%, respectively. They did not protect DNA from CuSO4-H2O2 and FeSO4-H2O2. Spermine apparently increased the CuSO4-H2O2-dependent injury to DNA. Polyamines attenuated H2O2-peroxidase-induced luminol dependent chemiluminescence. Total light emission from specimens containing 10 mM spermine or spermidine was attenuated by 85.3 ± 1.5 and 87 ± 3.6%. During 20 min incubation 1 mM spermine or spermidine decomposed 8.1 ± 1.4 and 9.2 ± 1.8% of diphenyl-picryl-hydrazyl radical. These results demonstrate that polyamines of well known anti-oxidant properties may act as pro-oxidants and enhance oxidative damage to DNA components in the presence of free iron ions and H2O2.