Fig 2. Effects of trans-Resveratrol on nitric oxide (NO) production by murine peritoneal macrophages.
Uninfected macrophages (105) and macrophages infected with Leishmania amazonensis at a 10:1 ratio stimulated with LPS or left unstimulated were incubated in the presence or absence of 33.2 μM pterostilbene (A), 45 μM piceatannol (C), 29 μM polydatin (E) and 30.5 μM oxyresveratrol (G). NO production was evaluated after 48h of treatment by the Griess method. The results of two independent experiments performed in duplicate are shown as the mean ± SEM nitrite concentration. * P <0.05, ** P <0.001, *** P<0.0001. Scavenger effect analysis was performed in a cell-free system by incubating SNAP solution (1 mM) as the NO donor with the same concentrations of trans-resveratrol used in NO (B, D, F, H). Rutin (1 mM), an NO scavenger, was used as positive control, and RPMI medium served as negative control. Nitrite levels were determined by the Griess method. The data represent the mean ± SEM of three independent experiments. * P <0.05, ** P <0.01, *** P <0.0001.