In vitro Anti-Inflammatory Activity of 23-Hydroxyursolic Acid Isolated from Cussonia bancoensis in Murine Macrophage RAW 264.7 Cells

Abstract

In the present study, the effects of various triterpenoids isolated from the stem bark of Cussonia bancoensis, namely, ursolic acid (1), 23-hydroxyursolic acid (2), 3-O-α-L-arabinopyranosyl-23-hydroxyursolic acid (3), and 3-O-β-D-glucopyranosyl-23-hydroxyursolic acid (4) were evaluated on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) release by the macrophage cell line RAW 264.7. Of the tested triterpenoids, 23-hydroxyursolic acid (2) was found to be the most potent inhibitor of NO production, and also significantly reduced PGE₂ release. Consistent with these observations, the protein and mRNA expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 enzymes were inhibited by 23-hydroxyursolic acid (2) in a concentration-dependent manner. Furthermore, 23-hydroxyursolic acid (2) inhibited the LPS-induced DNA binding activity of nuclear factor-κB (NF-κB), which was associated with a decrease of p65 protein levels in the nucleus. These results suggest that the 23-hydroxyursolic acid-mediated inhibition of iNOS and COX-2 expression, via blocking NF-κB activation, may mechanistically responsible for the anti-inflammatory effects of Cussonia bancoensis stem bark in vitro.

Cussonia bancoensis - Araliaceae - 23-hydroxyursolic acid - nitric oxide - prostaglandin E₂ - cyclooxygenase-2 - inducible nitric oxide synthase - nuclear factor κB

References

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