Fig. 6.

Fenofibrate inhibits NOS2 expression and NO release in primary cultures of cardiomyocytes infected with Trypanosoma cruzi. Cardiomyocytes were obtained and cultured at 37 °C under a 5% CO₂ atmosphere. Cardiomyocytes were infected at different parasite: cell ratios in six well polystyrene plates for 48 h. NO release was quantified by the Griess reaction in culture supernatants (A). T. cruzi-infected cardiomyocytes were treated with different doses of Fenofibrate. NOS2 expression was determined by Western blot with a specific antibody and normalized against α-actin (B). Cardiomyocytes were treated with 10 μM MK886, an antagonist of PPAR-α, 30 min before the addition of 100 μM Fen. 30 min after Fen treatment cells were infected with T. cruzi. After 48 h, NO levels were quantified by the Griess reaction in culture supernatants (C) and NOS2 expression was determined by Western blot with specific antibodies (D). Cardiomyocytes were treated with 100 μM Fen 30 min before infection with T. cruzi. After 15 or 30 min, IκBα cytosolic expression was determined by Western blot with specific antibodies (E). Protein levels were normalized against α-actin. Results are expressed as the mean of three independent experiments (three replicates/treatment) ± SEM. White bar: Uninfected control cells. Black bar: T. cruzi-infected cells. Grey bar: T. cruzi and Fen treated cells. Hatched dark-grey bar: MK pretreated, T. cruzi infected and Fen treated cells. **P < 0.001, ***P < 0.0001, T. cruzi-infected and Fen treated cells vs. infected cells; #P < 0.05, T. cruzi-infected vs. uninfected cells; §P < 0.05, T. cruzi-infected MK pre-treated and Fen treated cells vs. T. cruzi infected-Fen treated cells.