Differential inhibitory effects of inotilone on inflammatory mediators, inducible nitric oxide synthase and cyclooxygenase-2, in LPS-stimulated murine macrophage.
The inhibitory effects of inotilone and methylinotilone on the induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in murine RAW 264.7 cells activated with LPS were investigated. The results show that both hydroxyl groups on the benzene ring of the inotilone molecule are required for better anti-inflammatory effect. Western blotting and RT-PCR analyses demonstrated that inotilone blocked protein and mRNA expression of iNOS but not COX-2. Instead, inotilone inhibited prostaglandin E(2) production through decreasing the enzyme activity of COX-2. The repression of iNOS but not COX-2 expression may come from the differential effect of inotilone on nuclear factor-kappaB (NFkappaB) and CCAAT/enhancer-binding protein beta Treatment with inotilone resulted in the reduction of LPS-induced nuclear translocation of NFkappaB subunit and the NFkappaB-dependent transcriptional activity by blocking phosphorylation of inhibitor kappaB(IkappaB)alpha and p65 and subsequent degradation of inhibitor kappaBalpha. Inotilone also inhibited LPS-induced activation of PI3K/Akt and extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase. Our results suggest that inotilone may have potential to be developed into an effective anti-inflammatory agent.
Kuo
Yu-Ching
YC
Department of Food Science, Rutgers University, New Brunswick, NJ, USA.
Lai
Ching-Shu
CS
Wang
Ju-Ming
JM
Badmaev
Vladimir
V
Nagabhushanam
Kalyanam
K
Ho
Chi-Tang
CT
Pan
Min-Hsiung
MH
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism; D002478:Cells, Cultured; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D015232:Dinoprostone / Q000096:biosynthesis; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005663:Furans / Q000494:pharmacology*; D020672:I-kappa B Proteins / Q000378:metabolism; D018836:Inflammation Mediators / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D018942:Macrolides / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis*; D009573:Nitrites / Q000378:metabolism; D010766:Phosphorylation; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D000893:Anti-Inflammatory Agents; D022782:CCAAT-Enhancer-Binding Protein-beta; D005663:Furans; D020672:I-kappa B Proteins; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D018942:Macrolides; D016328:NF-kappa B; C000606205:Nfkbia protein, mouse; D009573:Nitrites; C513095:inotilone; D000072000:NF-KappaB Inhibitor alpha; D052247:Nitric Oxide Synthase Type II; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D015232:Dinoprostone