RESUMEN
The extract of Sappan Lignum, the heartwood of Caesalpinia sappan L., has been used in medicine to improve blood circulation. Recently, the application of microwave extraction methods has been a major focus of research into the extraction of components from natural sources. In this experiment, we compared the antiinflammatory effects of Sappan Lignum prepared by heat70% EtOH extraction (CSEH70E) and microwave70% EtOH extraction (CSEMW70E). Highperformance liquid chromatography analysis was used to identify the compounds in these extracts. The heat70% EtOH and microwave70% EtOH extracts of Sappan Lignum had different chromatograms. CSEMW70E significantly inhibited the protein expression of iNOS and COX2, PGE2, TNFα, and reduced NO and IL1ß production in macrophages exposed to LPS, whereas, only high concentrations of CSEH70E (20 µg/ml) resulted in any effects. Furthermore, CSEMW70E upregulated heme oxygenase1 (HO1) expression. In addition, the use of tin protoporphyrin, an inhibitor of HO1, confirmed the inhibitory effects of CSEMW70E on proinflammatory mediators. These results suggested that the CSEMW70Emediated upregulation of HO1 played an important role in the antiinflammatory effects of macrophages. Therefore, these findings showed that microwave extraction can be utilized to improve the extraction efficiency and biological activity of Sappan Lignum.
Asunto(s)
Antiinflamatorios/farmacología , Fabaceae/química , Hemo-Oxigenasa 1/metabolismo , Microondas , FN-kappa B/metabolismo , Extractos Vegetales/farmacología , Animales , Cromatografía Líquida de Alta Presión , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , ADN/metabolismo , Dinoprostona/metabolismo , Hemo-Oxigenasa 1/genética , Mediadores de Inflamación/metabolismo , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Metaloporfirinas/farmacología , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Nitritos/metabolismo , Unión Proteica/efectos de los fármacos , Protoporfirinas/farmacología , Células RAW 264.7 , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
Taraxacum coreanum Nakai is a dandelion that is native to Korea, and is widely used as an edible and medicinal herb. The present study revealed the neuroprotective effect of this plant against glutamate-induced oxidative stress in HT22 murine hippocampal neuronal cells. Ethanolic extracts from the aerial (TCAE) and the root parts (TCRE) of T. coreanum were prepared. Both extracts were demonstrated, by high performance liquid chromatography, to contain caffeic acid and ferulic acid as representative constituents. TCAE and TCRE significantly increased cell viability against glutamate-induced oxidative stress in mouse hippocampal HT22 cells. Western blot analysis revealed that treatment of HT22 cells with the extracts induced increased expression of the enzyme heme oxygenase-1 (HO-1), compared with untreated cells, in a concentration-dependent manner. Increased HO-1 enzymatic activity, compared with untreated cells, was also demonstrated following treatment with TCAE and TCRE. In addition, western blot analysis of the nuclear fractions of both TCAE and TCRE-treated HT22 cells revealed increased levels of nuclear factor erythroid 2 like 2 (Nrf2) compared with untreated cells, and decreased Nrf2 levels in the cytoplasmic fraction compared with untreated cells. The present study suggested that the neuroprotective effect of T. coreanum is associated with induction of HO-1 expression and Nrf2 translocation to the nucleus. Therefore, T. coreanum exhibits a promising function in prevention of neurodegeneration. Further studies will be required for the isolation and the full characterization of its active substances.