RESUMO
ACTG-toxin H (AH) originates from Alternaria sp. In this study, we explored the molecular mechanism underlying the anti-inflammatory properties of AH. Treatment with AH inhibited lipopolysaccharide (LPS)-induced interleukin-6, IL-1ß, inducible nitric oxide synthase, and cyclooxygenase-2 expression and nitric oxide production. Furthermore, AH inhibited LPS-induced P38 MAPK and Akt activation in RAW264.7 cells. Electrophoretic mobility shift assays (EMSAs) showed that AH inhibited LPS-induced nuclear factor-κB (NFκB) DNA-binding activity. Using transfection assay and measurement of an NFκB-sensitive promoter region, we found that transfection of toll-like receptor 4 (TLR4) increased LPS-induced NFκB transcription activity in 293T cells. AH significantly blocked LPS-induced NFκB activation in TLR4-transfected cells. Taken together, our data indicated that anti-inflammatory properties of AH resulted from the inhibition of proinflammatory cytokines and enzyme production via the TLR4/NFκB signaling pathway.
Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/imunologia , Micotoxinas/farmacologia , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Alternaria/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Ciclo-Oxigenase 2/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
The aqueous extract of Mori Fructus (MF) exerts a change of phenotype and a cytoprotective effect in macrophages. The present study was carried out to investigate the immunomodulating activity of MF on the expression of nitric oxide (NO), tumor necrosis factor alpha (TNF-alpha), co-stimulatory molecules and also interferon-gamma (IFN-gamma) in macrophages and splenocytes. Toll-like receptor 4 (TLR4) is a promising molecular target for immune-modulating drugs. It was hypothesized that one possible upstream signaling pathway leading to immunoregulation of MF may be mediated by TLRs. Multiple signaling molecules (NF-kappaB, ERK1/2, p38 and JNK) of the TLR4 signaling pathway were also detected. It was found that MF increased NO production and TNF-alpha secretion in RAW 264.7 and peritoneal macrophages, co-stimulatory molecules expression in peritoneal macrophages and IFN-gamma expression in splenocytes. Further studies indicated that MF could significantly induce the phosphorylation of signal molecules of MAPKs and the degradation of IkappaBalpha which finally led to the activation and nuclear translocation of nuclear factor-kappaB (NF-kappaB) for the target gene expression. All those notions disclosed that the aqueous extract MF is a new TLR4 activator, which induces a Th1 immune response as a consequence of induction of cytokines secretion, especially TNF-alpha and IFN-gamma.
Assuntos
Imunomodulação , Macrófagos Peritoneais/metabolismo , Extratos Vegetais/farmacologia , Receptor 4 Toll-Like/imunologia , Animais , Linhagem Celular , Feminino , Interferon gama/metabolismo , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Morus/química , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fosforilação , Transdução de Sinais , Baço/citologia , Baço/imunologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Scopoletin (1-50 microg/ml) inhibited the release of PGE2, TNF-alpha, IL-1beta and IL-6 and suppressed the expression of COX-2 in a concentration-dependent manner. These results suggest that scopoletin might suppress the production of such pro-inflammatory cytokines and exert inhibitory activity on LPS-induced PGE2 production through the depression of COX-2 expression.
Assuntos
Anti-Inflamatórios/farmacologia , Artemisia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Fitoterapia , Escopoletina/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Linhagem Celular/efeitos dos fármacos , Ciclo-Oxigenase 2 , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Isoenzimas/metabolismo , Lipopolissacarídeos , Camundongos , Prostaglandina-Endoperóxido Sintases/metabolismo , Escopoletina/administração & dosagem , Escopoletina/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Tongkyutang (TKT) is an Oriental herbal prescription, which has been successfully applied for the treatment of allergic disorders, mainly allergic-rhinitis in clinical medicine. However, its effect in experimental models remains unknown. METHODS: In a mouse model, the role of TKT was examined in mast cell-dependent allergic reactions and secretion of inflammatory cytokines. RESULTS: TKT concentration-dependently inhibited the ear-swelling response induced by intradermal injection of compound 48/80. TKT inhibited the compound 48/80-induced degranulation from mast cells in ear tissue. TKT dose-dependently inhibited the histamine release from the rat peritoneal mast cells by compound 48/80. TKT also showed inhibition of anti-dinitrophenyl IgE antibody-induced passive cutaneous anaphylaxis reaction by oral administration. Furthermore, TKT inhibited both IL-1beta and TNF-alpha secretion induced by PMA and A23187, respectively. CONCLUSIONS: Our findings provide evidence that TKT inhibits the mast cell-dependent allergic reactions and inflammatory cytokines secretion.