Figure 8.

Intracellular redox changes induced by steroid derivatives in bloodstream T. b. brucei. Black bars, parasites treated with EA (1, 2 and 3) or DHEA (4, 5 and 6) derivatives at 2× their corresponding EC₅₀ values (Table 2) for 4 h; Light gray bars, samples from the corresponding steroid-treated parasites exposed for 20 min to 1 mM DTT. The white and dark gray bars correspond to parasites treated with vehicle (1% v/v DMSO) for 4 h and with 250 μM menadiona (MEN) or diamide (DIA) for 20 min. The dark and light green bar correspond to parasites treated with 2 μM Conessine (CON, 5× EC₅₀) for 4 h and, thereafter, with 1 mM DTT for 20 min, respectively. The % biosensor reduction was calculated normalizing the values to the conditions giving full biosensor reduction (parasites treated with 1% DMSO and DTT 1 mM) and oxidation (parasites treated with 250 μM menadione for 20 min) and is expressed as mean ±SD. Each experiment was carried out at least three times. Statistical analysis was performed applying a one-way ANOVA test with 95% confidence intervals with the Dunnet’s multiple comparisons test.