Figure 2.

Quantification of mRNA involved in L-arginine transport and metabolism and NO production. Macrophages (5 × 10⁶) were treated with 30 nM of melatonin (squared dots), vehicle (5 × 10⁻⁶% ethanol, hexagonal dots) or untreated (triangular dots) for 4 h, infected with L. amazonensis (MOI 5:1) and collected after 4 and 24 h of infection. RT-qPCR of Cat2B (A), Cat1 (B), Arg1 (C), and Nos2 (D) were normalized by Gapdh quantification and the values were normalized by untreated-uninfected condition (0 h); (E) Frequency of NO producing cells and (F) mean of fluorescence intensity (MFI) of NO were quantified by DAF-FM label using flow cytometry. Each bar represents the average ± SEM of the values obtained in three independent experiments (n = 6–8). Statistical significance was determined based on two-tailed Student's t-test. ^*p < 0.05, infected macrophages (4 h or 24 h) compared to non-infected (0 h) ^**p < 0.05, melatonin-treated compared to untreated or vehicle.