Effects of juglone on the production of inflammatory mediators. (a) reactive oxygen species (ROS) production in J774.1 cells treated with lipopolysaccharide (LPS). Cells were treated with different concentrations of juglone (2.5, 5, and 10 μM) for 2 h, followed by treatment with 1 µg/mL LPS for an additional 24 h. (b) NO production in J774.1 cells treated with LPS. Cells were treated with increasing concentrations of juglone (3.1–50 μM or 0 μM control) for 2 h, followed by treatment with 1 μg/mL LPS for an additional 24 h. The levels of NO in the cell culture media were measured using Griess reagent. (c,d) Effects of juglone on the LPS/ATP-induced secretion of interleukin-1β (IL-1β) and IL-18 in J774.1 cells. J774.1 macrophages were treated with different concentrations of juglone for 2 h, followed by treatment with 1 μg/mL LPS for 6 h and treatment with 5 mM ATP for 1 h. The levels of IL-1β and IL-18 secreted in the culture medium were analyzed by enzyme-linked immunosorbent assay (ELISA). Data are presented as mean ± SD of three independent experiments. * p < 0.05; ** p < 0.01 vs. LPS or LPS + ATP cells, respectively.