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

• Published in: British journal of pharmacology 2006-05, Vol.148 (2), p.216-225
• Main Authors: Won, Jong-Heon, Im, Ho-Taek, Kim, Yang-Hee, Yun, Kyung-Jin, Park, Hee-Juhn, Choi, Jong-Won, Lee, Kyung-Tae
• Format: Article
• Language: English
• Subjects: Animals; Blotting, Western; Cell Line; Cyclooxygenase 2 - genetics; Cyclooxygenase 2 - metabolism; Dose-Response Relationship, Drug; Edema - chemically induced; Edema - drug therapy; Electrophoretic Mobility Shift Assay; Gene Expression - drug effects; Interleukin-1 - genetics; Interleukin-1 - metabolism; Interleukin-6 - genetics; Interleukin-6 - metabolism; Lipopolysaccharides - pharmacology; Male; Mice; Mice, Inbred ICR; Molecular Structure; NF-kappa B - genetics; NF-kappa B - metabolism; Nitric Oxide Synthase Type II - genetics; Nitric Oxide Synthase Type II - metabolism; Phosphorylation - drug effects; Protein Binding - drug effects; Rats; Rats, Sprague-Dawley; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Reverse Transcriptase Polymerase Chain Reaction; Saponins - chemistry; Saponins - pharmacology; Triterpenes - chemistry; Triterpenes - pharmacology; Tumor Necrosis Factor-alpha - genetics; Tumor Necrosis Factor-alpha - metabolism
• ISSN: 0007-1188

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.