Anti-inflammatory effect of buddlejasaponin IV through the inhibition of iNOS and COX-2 expression in RAW 264.7 macrophages via the NF-kappaB inactivation.

Abstract

Buddlejasaponin IV isolated from Pleurospermum kamtschatidum is an anti-inflammatory compound that inhibits NO, PGE(2) and TNF-alpha production. Here, we studied the mode of action of this compound. Buddlejasaponin IV (2.5-10 microM) reduced lipopolysaccaride (LPS (1 microg ml(-1)))-induced levels of iNOS and COX-2 at the protein levels, and iNOS, COX-2, TNF-alpha, interleukin (IL)-1beta and IL-6 mRNA expression in RAW 264.7 macrophages in a concentration-dependent manner, as determined by Western blotting and RT-PCR, respectively. Buddlejasaponin IV inhibited the LPS-induced activation of nuclear factor-kappaB (NF-kappaB), a transcription factor necessary for proinflammatory mediators, iNOS, COX-2, TNF-alpha, IL-1beta and IL-6 expression. This effect was accompanied by a parallel reduction in IkappaB-alpha degradation and phosphorylation, and by the nuclear translocation of the NF-kappaB p65 subunit. The effects of buddlejasaponin IV on acute phase inflammation were studied on serotonin- and carrageenan-induced paw edema. The antiedematous effect of buddlejasaponin IV was compared with 10 mg kg(-1) of indomethacin p.o. Maximum inhibitions of 26 and 41% were noted at a dose of 20 mg kg(-1) for serotonin- and carrageenan-induced paw edema, respectively. The analgesic effect of buddlejasaponin IV was evaluated using acetic acid-induced writhing and hot-plate tests. Buddlejasaponin IV (10 and 20 mg kg(-1), p.o.) was found to have a marked analgesic effect in both models. These results suggest that the inhibitions of the expressions of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6 by blocking NF-kappaB activation, are responsible for the anti-inflammatory effects of buddlejasaponin IV isolated from P. kamtschatidum.

• Authors: Jong-Heon Won, Ho-Taek Im, Yang-Hee Kim, Kyung-Jin Yun, Hee-Juhn Park, Jong-Won Choi, Kyung-Tae Lee
• Journal: British journal of pharmacology (Br J Pharmacol) Vol. 148 Issue 2 Pg. 216-25 (May 2006) ISSN: 0007-1188 [Print] England
• PMID: 16520738 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Interleukin-1
• Interleukin-6
• Lipopolysaccharides
• NF-kappa B
• Recombinant Fusion Proteins
• Saponins
• Triterpenes
• Tumor Necrosis Factor-alpha
• buddlejasaponin IV
• Nitric Oxide Synthase Type II
• Cyclooxygenase 2

Topics

• Animals
• Blotting, Western
• Cell Line
• Cyclooxygenase 2 (genetics, metabolism)
• Dose-Response Relationship, Drug
• Edema (chemically induced, drug therapy)
• Electrophoretic Mobility Shift Assay
• Gene Expression (drug effects)
• Interleukin-1 (genetics, metabolism)
• Interleukin-6 (genetics, metabolism)
• Lipopolysaccharides (pharmacology)
• Male
• Mice
• Mice, Inbred ICR
• Molecular Structure
• NF-kappa B (genetics, metabolism)
• Nitric Oxide Synthase Type II (genetics, metabolism)
• Phosphorylation (drug effects)
• Protein Binding (drug effects)
• Rats
• Rats, Sprague-Dawley
• Recombinant Fusion Proteins (genetics, metabolism)
• Reverse Transcriptase Polymerase Chain Reaction
• Saponins (chemistry, pharmacology)
• Triterpenes (chemistry, pharmacology)
• Tumor Necrosis Factor-alpha (genetics, metabolism)