Francisco et al. Increase of reactive oxygen species by desferrioxamine during experimental Chagas’ disease Figure 1 TBARS and PC levels in hepatocytes and serum levels of nitrate/nitrite in mice not infected or infected with T. cruzi and not treated or treated with desferrioxamine at days 7 and 21. Significant differences (P < 0.05) between groups are indicated by connecting lines group when compared with the NIT and INT groups (Fig. 1D). Figure 2A reveals that at 21 dpi, treatment with DFO in animals of IT group had induced a significant increase in serum nitrate/nitrite levels compared with 0, 7 and 14 dpi. Additionally, serum nitrate/nitrite levels in infected but untreated mice (INT group) were significantly higher at 14 dpi than those of the control animals (NINT group; data not shown). Figure 2B reveals that at 21 dpi, treatment with DFO in animals of IT group had induced a significant increase in SOD activity compared with 0, 7 and 14 dpi. No differences between the experimental and control groups were observed in the levels of GT at 0, 7 and 21 dpi or in SOD activity at 0, 7 and 14 dpi (data not shown). At 14 dpi, GT production in the livers of T. cruzi-infected mice that had been treated with DFO (IT group) was reduced significantly in comparison with non-infected but treated animals (NIT group) as shown in Figure 3A. At 21 dpi, SOD activity in serum of mice belonging to the IT group was increased significantly compared with those of NIT and INT group animals, indicating an antioxidant effect of DFO when associated with infection (Fig. 3B). No differences at 0, 7, 14 and 21 dpi were observed in animals of the NINT, NIT and INT groups (data not shown). 188 Redox Report 2010 Vol 15 No 4 Figure 2 Serum levels of nitrate/nitrite and serum activities of SOD in mice infected with T. cruzi and treated with desferrioxamine at days 0, 7, 14 and 21. Significant differences (P < 0.05) between days are indicated by connecting lines