Phenothiazinium Dyes Are Active against Trypanosoma cruzi In Vitro
Figure 1
Detection of T. cruzi in cultures treated with phenothiazine dyes or Benznidazole. T. cruzi was added to LLCMK2 cell monolayers and cultivated for 24 h, 37°C, 5% CO2. After washing with PBS, the T. cruzi cultures were incubated with the IC50 concentrations of MB (0.45 μM), NMB (0.09 μM), TBO (0.28 μM), DMMB (0.08 μM), and BZ (3.5 μM) for 72 hours, 37°C, and 5% CO2. The controls were composed by noninfected (negative control) or infected and nontreated cells (positive control) and cultivated at the same conditions. After treatment, the cultures were fixed with 4% paraformaldehyde for 20 minutes and washed with PBS and then the cell nucleus was stained with DAPI (Ex/Em = 340/488 nm). The parasites were detected by the emission of green fluorescence (Ex/Em = 488/510 nm). All figures were captured and analyzed in an Image Xpress Micro XLS Widefield High-Content Analysis System from Molecular Devices. The system also calculated the number of amastigotes in twenty-five images/well (x400). (a) Noninfected control. (b) Infected and nontreated control. (c), (d), (e), (f), and (g) Infected cultures treated with MB, NMB, TBO, DMMB,and BZ, respectively. (h) Percentage of inhibition compared to the nontreated control.