RESUMEN
Three new lupane-type saponins, acankoreosides F--H (1--3) were isolated from the methanol extract of the leaves of Acanthopanax koreanum NAKAI. The structures of these three saponins were established by chemical and spectroscopic analysis as 3alpha,30-dihydroxylup-20(29)-en-23,28-dioic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (1), 3alpha,30-dihydroxylup-23-al-20(29)-en-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (2), and (20S) 3alpha-hydroxylup-23-al-28,29-dioic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (3), respectively. The effects of the isolates (1-3) on the lipopolysaccharide-induced production of nitric oxide and prostaglandin E2 were evaluated in RAW 264.7 macrophages.
Asunto(s)
Eleutherococcus/química , Glicósidos/aislamiento & purificación , Hojas de la Planta/química , Saponinas/química , Saponinas/farmacología , Triterpenos/química , Triterpenos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Secuencia de Carbohidratos , Dinoprostona/química , Glicósidos/farmacología , Hidrólisis , Macrófagos/química , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Óxido Nítrico/biosíntesis , Espectrometría de Masa Bombardeada por Átomos VelocesRESUMEN
In the present study, the effects of several triterpenes isolated from the leaves of Acanthopanax chiisanensis (Araliaceae), namely, chiisanoside, isochiisanoside, 22-hydroxychiisanoside and chiisanogenin (the aglycone of chiisanoside) were evaluated on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production by the RAW 264.7 macrophage cell line. Of the triterpenes tested, chiisanoside was found to most potently inhibit NO and PGE2 production. In addition, chiisanoside significantly reduced the release of inflammatory cytokines like TNF-alpha and IL-1beta. Consistent with these observations, the protein and mRNA expression levels of iNOS and COX-2 enzyme were found to be inhibited by chiisanoside in a concentration-dependent manner. Furthermore, chiisanoside inhibited the nuclear factor-kappaB (NF-kappaB) activation induced by LPS and this was associated with a reduction in p65 protein in the nucleus and with the phosphorylations of ERK1/2 and JNK MAP kinases. Taken together, our data indicate that the anti-inflammatory properties of chiisanoside might be the result from the inhibition of iNOS, COX-2, TNF-alpha and IL-1beta expression through the down-regulation of NF-kappaB binding activity.