RESUMO
Three new (1-3) and four known (4-7) compounds were isolated from the stems of Baccaurea ramiflora. By analysis of 1D, 2D NMR, and MS data, the new compounds were identified as 4'-O-(6- O-vanilloyl)-beta-D-glucopyranosyl tachioside D (1), 6'-O-vanilloylpicraquassioside D (2), and 6'-O-vanilloylicariside B(5) (3). Compound 1 exhibited significant DPPH radical-scavenging activity, with an IC(50) value of 36.9 microM, while compound 4 revealed weak antioxidant activity against H (2)O(2)-induced impairment in PC12 cells.
Assuntos
Antioxidantes/isolamento & purificação , Dissacarídeos/isolamento & purificação , Magnoliopsida/química , Monossacarídeos/isolamento & purificação , Extratos Vegetais/química , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo , Dissacarídeos/farmacologia , Peróxido de Hidrogênio , Concentração Inibidora 50 , Monossacarídeos/farmacologia , Células PC12 , Picratos , Extratos Vegetais/farmacologia , Caules de Planta , RatosRESUMO
Eight new lignan glucosides, tarennanosides A-H (1-8, resp.), were isolated from the whole plant of Tarenna attenuata, together with three known compounds, fernandoside, (-)-lyoniresinol, and (-)-isolariciresinol. The planar structures of new compounds were elucidated mainly by analysis of physical and spectroscopic data, and the absolute configurations were determined by acid hydrolysis as well as CD spectroscopy. Compounds 1 and 2 exhibited potent antioxidant activities against H2O2-induced impairment in PC12 cells. Preliminary mechanism study by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method showed that these two compounds could act as radical scavengers.
Assuntos
Antioxidantes/química , Glucosídeos/química , Peróxido de Hidrogênio/química , Monossacarídeos/química , Naftalenos/química , Rubiaceae/química , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Monossacarídeos/isolamento & purificação , Monossacarídeos/farmacologia , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Células PC12 , Picratos/química , Picratos/farmacologia , RatosRESUMO
Previous studies showed that bis(alpha-furancarboxylato)oxovanadium(IV) (BFOV), an orally active anti-diabetic organic vanadium complex, could improve insulin resistance in animals with type 2 diabetes. The present study has been carried out to evaluate the effects of BFOV on insulin-resistant glucose metabolism using dexamethasone-treated 3T3-L1 adipocytes as an in-vitro model of insulin resistance. The results showed that BFOV, similar to vanadyl sulfate and rosiglitazone, caused a concentration-dependent increase in glucose consumption by insulin-resistant adipocytes. Moreover, BFOV enhanced the action of insulin and completely prevented the development of insulin resistance induced by dexamethasone, leading to glucose consumption equal to that by normal cells. In addition, dexamethasone reduced the mRNA expression of insulin receptor substrate 1 (IRS-1) and glucose transporter 4 (GLUT4) in 3T3-L1 adipocytes, while BFOV normalized the expression of IRS-1 and GLUT4. These findings suggest that BFOV prevents and improves dexamethasone-induced insulin resistance in 3T3-L1 adipocytes by enhancing expression of IRS-1 and GLUT4 mRNA.
Assuntos
Adipócitos/efeitos dos fármacos , Dexametasona/farmacologia , Insulina/farmacologia , Compostos Organometálicos/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Relação Dose-Resposta a Droga , Glucocorticoides/farmacologia , Glucose/metabolismo , Glucose/farmacologia , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Hipoglicemiantes/farmacologia , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rosiglitazona , Tiazolidinedionas/farmacologia , Compostos de Vanádio/farmacologiaRESUMO
Two new phenols, 6'- O-vanilloylisotachioside ( 1) and 6'- O-vanilloyltachioside ( 2), together with nine known compounds, were isolated from the leaves of Baccaurea ramiflora (Euphorbiaceae). The structures of the new compounds were elucidated mainly by analysis of physical and spectroscopic data. Compounds 1 - 10 were tested for antioxidant activities by using MTT and DPPH assays. Seven compounds, 1, 2, and 4 - 8, revealed potent antioxidant activities against H (2)O (2)-induced impairment in PC12 cells, and exhibited significant DPPH radical-scavenging activities with IC (50) values of 86.9, 142.9, 15.2, 37.6, 35.9, 30.2, and 79.8 microM, respectively.
Assuntos
Antioxidantes/farmacologia , Euphorbiaceae , Sequestradores de Radicais Livres/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/uso terapêutico , Compostos de Bifenilo , Células Cultivadas , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/uso terapêutico , Humanos , Peróxido de Hidrogênio/química , Fenóis/administração & dosagem , Fenóis/química , Fenóis/farmacologia , Fenóis/uso terapêutico , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Folhas de PlantaRESUMO
Six new mixed lignan-neolignans and 20 known compounds were isolated from the whole plant of Tarenna attenuata. By analysis of physical and spectroscopic data, the structures of the new compounds were elucidated as (1R,5R,6R)-6-{4-O-[2-(1-(4-hydroxy-3-methoxyphenyl))glycerol]-3,5-dimethoxyphenyl}-3,7-dioxabicyclo[3.3.0]octan-2-one (1), 5' '-methoxyhedyotisol A (2), 4' '-O-(8-guaiacylglycerol)buddlenol A (3), 5' '-methoxy-4' '-O-(8-guaiacylglycerol)buddlenol A (4), 4,6-dimethoxy-5-hydroxy-3-hydroxymethyl-2-(3,4,5-trimethoxyphenyl)-2,3-dihydrobenzofuran (5), and 7-O-ethylguaiacylglycerol (6). Compounds 1, 5, 6, and 8 showed potent antioxidant activities against H2O2-induced impairment in PC12 cells, and compounds 1, 2, 5, and 7 scavenged DPPH radical strongly with IC50 values of 72, 87, 45, and 55 microM, respectively.
