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.
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.
Won
Jong-Heon
JH
Department of Biochemistry, College of Pharmacy, Kyung-Hee University, 1 Hoegi-Dong, Dongdaemun-Gu, Seoul 130-701, South Korea.
Im
Ho-Taek
HT
Kim
Yang-Hee
YH
Yun
Kyung-Jin
KJ
Park
Hee-Juhn
HJ
Choi
Jong-Won
JW
Lee
Kyung-Tae
KT
D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy; D024202:Electrophoretic Mobility Shift Assay; D015870:Gene Expression / Q000187:drug effects; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D015394:Molecular Structure; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012503:Saponins / Q000737:chemistry / Q000494:pharmacology*; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism
D007375:Interleukin-1; D015850:Interleukin-6; D008070:Lipopolysaccharides; D016328:NF-kappa B; D011993:Recombinant Fusion Proteins; D012503:Saponins; D014315:Triterpenes; D014409:Tumor Necrosis Factor-alpha; C418227:buddlejasaponin IV; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2