Figure 4.

Effect of lupeol cinnamate (compound 3) (A) and betulinic acid (compound 5) (B) on nitrite levels produced in response to lipopolysaccharide (LPS, 1 μg/mL) added to J774A.1 murine macrophages for 24 h alone or in the presence of the selective cannabinoid CB1 receptor antagonist AM251 (1 μM) and/or in presence of the selective cannabinoid CB2 receptor antagonist SR144528 (SR144, 0.1 μM). Treatment with antagonists started 30 min before exposure to compounds 3 and/or 5. LPS (1 μg/mL) was given 30 min after the administration of the drugs (antagonists, compounds 3 and 5). Results are reported as a percentage of nitrites and are expressed as means ± SEM of three or four independent experiments. § p < 0.0001 vs. control (cells without LPS); ** p < 0.01 and **** p < 0.0001 vs. LPS as assessed by one-way ANOVA, followed by Tukey’s multiple comparisons test.