RESUMO
A bioassay-guided fractionation of the CH(2)Cl(2) extract of Selaginella tamariscina yielded six sterols 1-6 such as (4α, 5α)-4, 14-dimethylcholest-8-en-3-one (1), ergosta-4, 6, 8(14), 22-tetraene-3-one (2), ergosterol endoperoxide (3), 7ß-hydroxycholesterol (4), 7ß-hydroxysitosterol (5), and 7α-hydroxysitosterol (6). The structures of isolated compounds were determined using spectroscopic methods. Among these isolates, compounds 2-5 showed potent cytotoxicity against five human tumor cells, while compounds 1 and 6 did not. In the case of compounds 1 and 2, 3-oxo sterol derivatives, compound 1 was inactive, but compound 2 showed potent cytotoxicity. In addition, compound 5 exhibited potent cytotxicity, but, compound 6 which is the 7-epimer of compound 5 was weakly active against tumor cell lines. Therefore, in the case of oxysterol derivatives, the cytotoxicity appeared to be affected by the structural differences, i.e. the configuration of hydroxyl group and the number of conjugated double bond. Taken all together, the present study isolated six sterols from S. tamariscina for the first time based on a bioassay-guided fractionation and indicated that isolated oxysterols could exhibit the cytotoxic effects against tumor cells, suggesting that S. tamariscina might be a promising candidate for the development of anticancer agents.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Descoberta de Drogas , Neoplasias/tratamento farmacológico , Fitosteróis/química , Fitosteróis/farmacologia , Selaginellaceae/química , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Isomerismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rotação Ocular , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Infravermelho , Temperatura de TransiçãoRESUMO
A new furofuran lignan, 4-hydroxykobusin (3), together with known lignans, kobusin (1), and 7,7'-dihydroxybursherenin (2), were isolated from the whole plant of Geranium thunbergii Sieb. et Zucc (Geraniaceae). The structures were determined based on the spectral data and a comparison with the published data. This is the first report of the presence of furofuran lignan in Geranium species.
Assuntos
Furanos/química , Geranium/química , Lignanas/química , Linhagem Celular , Furanos/isolamento & purificação , Interleucina-6/análise , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria UltravioletaRESUMO
We have isolated four different phenylethanoid glycosides (purpureaside A, desrhamnosyl acteoside, calceolarioside B and plantainoside D) from the leaves of Digitalis purpurea (foxglove). The effects of these glycosides on activator protein-1 (AP-1)-mediated inducible nitric oxide synthase (iNOS) gene expression in the Raw264.7 macrophage cell line have been studied. Of these four glycosides, purpureaside A potently inhibited iNOS induction by lipopolysaccharide (LPS). Increase in iNOS mRNA by LPS was completely suppressed by purpureaside A. Purpureaside A did not significantly affect LPS-inducible nuclear factor-kappaB (NF-kappaB) activation or the nuclear translocation of p65. Moreover, a reporter gene assay using AP-1 specific luciferase reporter revealed that the enhanced activity of AP-1 by LPS was completely abolished in cells treated with purpureaside A. These results demonstrated that purpureaside A inhibited LPS-inducible iNOS expression in macrophages through the suppression of AP-1, but not of NF-kappaB.
Assuntos
Digitalis/química , Glicosídeos/farmacologia , Óxido Nítrico Sintase/biossíntese , Extratos Vegetais/farmacologia , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Macrófagos/enzimologia , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Folhas de Planta/química , Fator de Transcrição AP-1/fisiologiaRESUMO
A bioassay-guided fractionation of the ethyl acetate soluble fraction from the stem bark of Styrax japonica S. et Z. (Styracaceae) yielded two new lignan compounds, styraxjaponoside A (1) and styraxjaponoside B (2), along with three known compounds, matairesinoside (3), egonol glucoside (4), and dihydrodehydrodiconiferyl alcohol 9'-O-glucoside (5). The structures of compounds 1-5 were determined by spectroscopic method, as well as 1D- and 2D-NMR (HSQC, 1H-1H COSY, and HMBC) spectroscopy. Among them, compound 2 exhibited potent inhibitory activity against matrix metalloproteinase (MMP)-1, and prevented the UV-induced changes in the MMP-1 expression. In addition, compounds 3 and 5 were isolated from this plant for the first time.
Assuntos
Lignanas/farmacologia , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/química , Styrax/química , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células Cultivadas , Cromatografia em Camada Fina , Ensaios de Seleção de Medicamentos Antitumorais , Fibroblastos/efeitos dos fármacos , Humanos , Hidrólise , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Casca de Planta/química , Pró-Colágeno/química , Inibidores de Proteases/isolamento & purificação , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria Ultravioleta , Raios UltravioletaRESUMO
In order to elucidate the structure-antiviral activity relationship of cecropin A (1-8)-magainin 2 (1-12) (termed CA-MA) hybrid peptide, several analogues with amino acid substitutions were synthesized. In a previous study, it was shown that serine at position 16 in CA-MA hybrid peptide was very important for antimicrobial activity. Analogues were designed to increase the hydrophobic property by substituting a hydrophobic amino acid residue (S --> A, V, F or W, position 16) in the CA-MA hybrid peptide. In this study, the structure-antiviral activity relationships of CA-MA and its analogues were investigated. In particular, substitution of Ser with a hydrophobic amino acid, Val, Phe or Trp at position 16 caused a dramatic increase in the virus-cell fusion inhibitory activity. These results suggested that the hydrophobicity at position 16 in the hydrophobic region of CA-MA is important for potent antiviral activity.
Assuntos
Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteína gp120 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Relação Estrutura-Atividade , Proteínas de Xenopus/farmacologia , Animais , Anti-Infecciosos/síntese química , Peptídeos Catiônicos Antimicrobianos/síntese química , Antígenos CD4/genética , Antígenos CD4/metabolismo , Chlorocebus aethiops , Células Gigantes/efeitos dos fármacos , Proteína gp120 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/genética , HIV-1/genética , Células HeLa , Humanos , Magaininas , Proteínas Recombinantes de Fusão/síntese química , Vaccinia virus/genética , Células Vero , Proteínas de Xenopus/síntese químicaRESUMO
The methylene chloride soluble fraction of MeOH extract from the stem bark of Styrax japonica S. et Z. (Styracaceae) showed significant cytotoxicity by SRB method against five human tumor cell lines. Four known pentacyclic triterpenoids, oleanolic aldehyde acetate (1), erythrodiol-3-acetate (2), euphorginol (3), and anhydrosophoradiol-3-acetate (4) were isolated by activity-guided fractionation. Their structures were determined by chemical and spectral analysis. Compounds 1-4 were isolated from S. japonica for the first time.
Assuntos
Styrax , Triterpenos/toxicidade , Linhagem Celular Tumoral , Humanos , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Caules de Planta , Triterpenos/química , Triterpenos/isolamento & purificaçãoRESUMO
Four flavonoids (1-4), a phenylethyl glycoside (5), and a phenylpropanoid glycoside (6) were isolated from the flowers of Buddleia officinalis (Loganiaceae). Their structures were determined by chemical and spectral analysis. Among the isolated compounds, luteolin (1) and acteoside (6) exhibited the most potent antioxidative activity on the NBT superoxide scavenging assay. In addition, compounds 1-6 revealed weak antifungal activity, and no hemolytic activity.
Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Buddleja , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Flores , Testes de Sensibilidade Microbiana/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologiaRESUMO
A new phenolic amide, dihydro-N-caffeoyltyramine (1) was isolated from the root bark of Lycium chinense Miller, along with known compounds, trans-N-caffeoyltyramine (2), cis-N-caffeoyltyramine (3), and lyoniresinol 3alpha-O-beta-D-glucopyranoside (4). Their structures were determined by spectroscopic analysis. A NBT superoxide scavenging assay revealed that three phenolic amides showed potent antioxidative activity.