In vivo anti-inflammatory activity of Liquidambar formosana Hance infructescence extract

Purpose: To evaluate the anti-inflammatory activity of Liquidambar formosana Hance infructescence (Liquidambaris fructus, ELF) in vivo, and clarify its underlying mechanisms. Methods: The in vivo anti-inflammatory activity of ELF was examined by xylene-induced ear swelling test in mice as well as carrageenan-induced paw edema method in rats. The levels of inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-10) in serum were measured by enzyme-linked immunosorbent assay (ELISA), while the expressions of COX-2, iNOS and NF-κB p65 in paw tissue of rats were evaluated by western blot.Results: After ELF treatment, the levels of TNF-α (p < 0.001), IL-1β (p < 0.001) and IL-6 (p < 0.001) in serum decreased and the levels of anti-inflammatory cytokine IL-10 increased (p < 0.01). In addition, ELF treatment resulted in decrease of COX-2 (p < 0.01), iNOS (p < 0.01) and NF-κB p65 (p < 0.01) expressions in Wistar rats.Conclusion: The results reveal that ELF possesses significant anti-inflammatory effect in vivo. The anti-inflammatory activity is associated with the levels of TNF-α, IL-1β, IL-6 and IL-10 in serum. Furthermore, the suppression of NF-κB p65, iNOS and COX-2 is linked to its anti-inflammatory effect. These results provide a rationale for the use of Liquidambaris fructus in inflammatory disease in traditional medicine.Keywords: Anti-inflammatory activity, Liquidambaris fructus, Cytokines, Ear swelling test, Paw edema