cis-Aconitic Acid, a Constituent of Echinodorus grandiflorus Leaves, Inhibits Antigen-Induced Arthritis and Gout in Mice.

-Aconitic acid is a constituent from the leaves of , a medicinal plant traditionally used in Brazil to treat inflammatory conditions, including arthritic diseases. The present study aimed to investigate the anti-arthritic effect of -aconitic acid in murine models of antigen-induced arthritis and monosodium urate-induced gout. The possible underlying mechanisms of action was evaluated in THP-1 macrophages. Oral treatment with -aconitic acid (10, 30, and 90 mg/kg) reduced leukocyte accumulation in the joint cavity and C-X-C motif chemokine ligand 1 and IL-1 levels in periarticular tissue. -Aconitic acid treatment reduced joint inflammation in tissue sections of antigen-induced arthritis mice and these effects were associated with decreased mechanical hypernociception. Administration of -aconitic acid (30 mg/kg p. o.) also reduced leukocyte accumulation in the joint cavity after the injection of monosodium urate crystals. -Aconitic acid reduced the release of TNF- and phosphorylation of IB in lipopolysaccharide-stimulated THP-1 macrophages, suggesting that inhibition of nuclear factor kappa B activation was an underlying mechanism of -aconitic acid-induced anti-inflammatory effects. In conclusion, -aconitic acid has significant anti-inflammatory effects in antigen-induced arthritis and monosodium urate-induced arthritis in mice, suggesting its potential for the treatment of inflammatory diseases of the joint in humans. Additionally, our findings suggest that this compound may contribute to the anti-inflammatory effect previously reported for extracts.