RESUMO
We identified a bioactive herbal medicine with anti-inflammatory activity from an ethanol extract derived from the bark of Dioscorea batatas DECNE (BDB) in RAW264.7 cells. We examined the effects of BDB on nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in LPS-induced RAW264.7 cells. BDB consistently inhibited both NO and PGE(2) production in a dose-dependent manner, with an IC(50) of 87-71 µg/ml, respectively. The reduction of NO and PGE(2) production were accompanied by a reduction in iNOS and COX-2 protein expression, as evaluated by Western blotting. To evaluate the action mode of BDB and its ability to inhibit iNOS and COX-2 protein expression, we assessed the effects of BDB on nuclear factor-κB (NF-κB) DNA-binding activity, NF-κB-dependent reporter gene activity, inhibitory factor-κB (IκB) phosphorylation and degradation, and p65 nuclear translocation. BDB suppressed DNA-binding activity and reporter gene activity as well as translocation of the NF-κB p65 subunit. BDB also down-regulated IκB kinase (IKK), thus inhibiting LPS-induced both phosphorylation and the degradation of IκBα. In addition, BDB also inhibited the LPS-induced activation of ERK1/2.
Assuntos
Inibidores de Ciclo-Oxigenase 2/farmacologia , Dioscorea/química , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/enzimologia , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Casca de Planta/químicaRESUMO
In order to investigate the potential of Platycarya strobilacea fruit extract as an active ingredient for cosmetics, we measured their free-radical scavenging activity, elastase inhibitory activity, the expression of MMP-1 (matrix metalloproteinase-1), and type I collagen synthesis in normal human fibroblast cells. To isolate the main component compounds from P. strobilacea fruit extract, we purified the extract through solvent fractionation, column chromatography, and recrystallization. The component compounds were identified as ellagic acid and 4-O-xyloside of ellagic acid (ellagic acid 4-O-xylopyranoside). P. strobilacea fruit extract and ellagic acid increased the expression of type I collagen mRNA in a dose-dependent manner (up to 37% and 41% at 20 microg/ml and 1.0 microg/ml, respectively), comparable to that of ascorbic acid (up to 39% at 500 muM). A clinical study of measurements using visual evaluation and image analysis showed a statistically significant difference (p < 0.05) between the effects of the test and placebo products. This result suggests that P. strobilacea fruit extract could be used as an active ingredient for antiaging cosmetics.