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

Abstract

1 Buddlejasaponin IV isolated from Pleurospermum kamtschatidum is an anti-inflammatory compound that inhibits NO, PGE 2 and TNF-a production. Here, we studied the mode of action of this compound. 2 Buddlejasaponin IV (2.5-10 mM) reduced lipopolysaccaride (LPS (1 mg ml À1 ))-induced levels of iNOS and COX-2 at the protein levels, and iNOS, COX-2, TNF-a, interleukin (IL)-1b and IL-6 mRNA expression in RAW 264.7 macrophages in a concentration-dependent manner, as determined by Western blotting and RT-PCR, respectively. 3 Buddlejasaponin IV inhibited the LPS-induced activation of nuclear factor-kB (NF-kB), a transcription factor necessary for proinflammatory mediators, iNOS, COX-2, TNF-a, IL-1b and IL-6 expression. This effect was accompanied by a parallel reduction in IkB-a degradation and phosphorylation, and by the nuclear translocation of the NF-kB p65 subunit. 4 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 À1 of indomethacin p.o. Maximum inhibitions of 26 and 41% were noted at a dose of 20 mg kg À1 for serotonin-and carrageenan-induced paw edema, respectively. 5 The analgesic effect of buddlejasaponin IV was evaluated using acetic acid-induced writhing and hot-plate tests. Buddlejasaponin IV (10 and 20 mg kg À1 , p.o.) was found to have a marked analgesic effect in both models. 6 These results suggest that the inhibitions of the expressions of iNOS, COX-2, TNF-a, IL-1b and IL-6 by blocking NF-kB activation, are responsible for the anti-inflammatory effects of buddlejasaponin IV isolated from P. kamtschatidum.

Kakkalide and Its Metabolite Irisolidone Ameliorate Carrageenan-Induced Inflammation in Mice by Inhibiting NF-κB Pathway

“…These pro-inflammatory cytokines, TNF-α and IL-1β, are important mediators of inflammation and autoimmune disease. The expression of these pro-inflammatory cytokines and pro-inflammatory enzymes is regulated by transcription factor NF-κB [3,5,29]. Irisolidone and kakkalide inhibited the expression of these pro-inflammatory cytokines and enzymes in vitro and in vivo.…”

“…NF-κB is an ubiquitous transcription factor that regulates inflammatory responses, cellular proliferation, and cell adhesion [5]. In an unstimulated state, NF-κB dimers are localized in the cytoplasm as inactive complexes associated with members of the inhibitor of κB (IκB) family.…”

Tocotrienols Suppress Proinflammatory Markers and Cyclooxygenase‐2 Expression in RAW264.7 Macrophages

“…Many studies have used these two cytokines as important markers of inflammation [26,27]. The up-regulation of IL-6 and TNF-a is seen in many disorders such as rheumatoid arthritis, multiple myeloma and chronic obstructive pulmonary disease [28][29][30].…”

Mollugin Inhibits the Inflammatory Response in Lipopolysaccharide-Stimulated RAW264.7 Macrophages by Blocking the Janus Kinase-Signal Transducers and Activators of Transcription Signaling Pathway

“…12) To explore the anti-inflammatory effects of mollugin, we determined the effects of mollugin on the mrNA and protein expression of these cytokines and iNoS and on the release of No in lPS-stimulated rAW264.7 macrophages according to previously reported methods. 13,14) As depicted in Fig. 2, mollugin markedly reduced the release of No and the protein and mrNA expression levels of iNoS, il-1β and IL-6 in a concentration-dependent manner in LPS-stimulated RAW264.7 cells.…”