Vernonia polysphaera Baker: Anti-inflammatory activity in vivo and inhibitory effect in LPS-stimulated RAW 264.7 cells.

Species of the Vernonia genius are widely distributed across the world. In traditional communities, they are commonly used in popular medicine for the treatment of inflammatory diseases. The objective of the present study was to evaluate the anti-inflammatory activity of Vernonia polysphaera Baker hydroalcoholic extract. A λ-carrageenan-induced paw edema and peritonitis model was established in BALB/c mice. The in vitro activity of the extract was measured on LPS-stimulated RAW 264.7 cells. There was no toxic effect on mice or on the cells treated with the extract. Animals treated with V. polysphaera extract demonstrated inhibition of paw edema in comparison with the untreated animals at all the analyzed doses. In peritonitis, treatment with the extract at a dose of 500 mg/kg resulted in a lower total leukocyte count in the peritoneal fluid and blood and lower levels of IL-1β, IL-6, TNF-α and PGE-2 than the control group. Cells treated with 50 and 100 μg/mL of the extract exhibited lower levels of nitrite and pro-inflammatory cytokine production and lower COX-2, NF-κB expression. The V. polysphaera extract demonstrated an anti-inflammatory effect, interfering with cell migration, reducing pro-inflammatory cytokine levels and COX-2 expression and consequent interference with PGE-2, as well as inhibiting NF-κB transcription.