RESUMEN
Bioassay-guided fractionation of the methanolic extract from the roots of Cynanchum atratum has resulted in the isolation of three new pregnane glycosides (1-3) along with four known compounds (4-7). Their structures were identified by analysis of the spectroscopic data including extensive 2D NMR. All of the isolates were evaluated for their potential to inhibit the melanin production in α-melanocyte stimulating hormone (α-MSH)-activated B16 melanoma cells. Of these, compounds 4-7 dose-dependently inhibited the melanin production with the IC50 values ranging from 4⯵M to 33⯵M.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Cynanchum/química , Glicósidos/farmacología , Melaninas/antagonistas & inhibidores , Melanoma Experimental/tratamiento farmacológico , Extractos Vegetales/farmacología , Pregnanos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glicósidos/química , Glicósidos/aislamiento & purificación , Humanos , Melaninas/biosíntesis , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Conformación Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Pregnanos/química , Pregnanos/aislamiento & purificación , Relación Estructura-ActividadRESUMEN
A non-glycosidic iridoid, campsinol (1), and two iridoid glucosides, 7-O-(Z)-p-coumaroylcachineside V (2) and 7-O-(E)-p-coumaroylcachineside I (3), were isolated from the fresh flowers of Campsis grandiflora along with five known iridoid glycosides, ixoroside (4), campsiside (5), cachineside I (6), 5-hydroxycampenoside (7), and 5-hydroxycampsiside (8), and two known phenylpropanoid glycosides, acteoside (9) and leucosceptoside A (10). The structures of these compounds were determined based on the NMR and Mass spectroscopic data and other chemical evidences.
Asunto(s)
Bignoniaceae/química , Flores/química , Iridoides/química , Iridoides/aislamiento & purificación , Extractos Vegetales/química , Glicósidos/química , Glicósidos/aislamiento & purificación , Glicósidos Iridoides/química , Glicósidos Iridoides/aislamiento & purificación , Estructura MolecularRESUMEN
The activity-guided fractionation of the MeOH extract of the rhizomes and roots of Nardostachys chinensis led to the isolation of two new sesquiterpenoids, narchinol B (8) and narchinol C (9), along with 10 known compounds, ursolic acid (1), nardosinone (2), pinoresinol (3), desoxo-narchinol A (4), kanshone B (5), epoxyconiferyl alcohol (6), debilon (7), 4α,5-dimethyl-1,3-dioxo-1,2,3,4,4α,5,6,7-octahydronaphthalene (10), p-coumaric acid (11), and isoferulic acid (12). Their structures were determined using spectroscopic techniques, which included 1D- and 2D-NMR. Among the isolates, compounds 2, 4, 5, 8 and 9 showed inhibitory activity against LPS-induced NO production with IC(50) values of 4.6-21.6 µM.
Asunto(s)
Macrófagos/citología , Nardostachys/metabolismo , Óxido Nítrico/metabolismo , Extractos Vegetales/farmacología , Animales , Diseño de Fármacos , Concentración 50 Inhibidora , Lipopolisacáridos/química , Espectroscopía de Resonancia Magnética/métodos , Metanol/química , Ratones , Modelos Químicos , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/química , Raíces de Plantas/metabolismo , Rizoma/química , Espectrofotometría/métodosRESUMEN
Bioactivity-guided isolation of the methanol extract of the stems of Dendrobium nobile yielded a new phenanthrene together with nine known phenanthrenes and three known bibenzyls. Their structures were elucidated by analysis of the spectroscopic data including 2D-NMR. All of the isolates were evaluated for their potential to inhibit the LPS-induced production of nitric oxide in murine macrophage RAW 264.7 cells. Compounds 1-4, 7-13 inhibited nitric oxide production with the IC(50) values ranging from 9.6 microM to 35.7 microM.
Asunto(s)
Dendrobium/química , Macrófagos/efectos de los fármacos , Óxido Nítrico/antagonistas & inhibidores , Fenantrenos/farmacología , Animales , Línea Celular , Concentración 50 Inhibidora , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Fenantrenos/química , Fenantrenos/aislamiento & purificación , Extractos Vegetales , Relación Estructura-ActividadRESUMEN
Beta-carboline alkaloids including harmalol, harmaline, norharmane, harmol, harmine and harmane are important constituents of the medicinal plant, Perganum harmala L. (Zygophylaceae), which has been used in traditional medicine. In the present study, the antiplatelet activities of six beta-carboline alkaloid compounds were investigated in vitro. At a concentration of 200 microM, these compounds have no effect on arachidonic acid (AA)-, thrombin- and U46619 (a thromboxane A2 mimic)-stimulated platelet aggregation. On the contrary, it was revealed that collagen-induced platelet aggregation could be inhibited by these compounds with different potencies (harmane and harmine were most potent, harmol had medium potency, and harmol, norharmane, harmalol and harmaline had a weak, non significant effect), indicating a selective inhibition on collagen-mediated platelet activation. Consistently, further study revealed that collagen-mediated phospholipase (PL) Cgamma2 and protein tyrosine phosphorylation, cytosolic calcium mobilization and arachidonic acid liberation were completely inhibited by harmane and harmine in a concentration-dependent manner, while the other compounds were only partially or not effective at all. Taken together, these results indicate that three of these six beta-carboline alkaloids can selectively affect collagen-induced platelet aggregation with different potencies; in particular, harmane and harmine were most potent, and their antiplatelet activities may be mediated by inhibiting PLCgamma2 and protein tyrosine phosphorylation with sequential suppression of cytosolic calcium mobilization and arachidonic acid liberation, indicating that harmane and harmine have a potential to be developed as a novel agent for atherothrombotic diseases.
Asunto(s)
Alcaloides/farmacología , Carbolinas/farmacología , Peganum , Fosfolipasa C gamma/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Animales , Ácido Araquidónico/metabolismo , Plaquetas/metabolismo , Calcio/metabolismo , Carbolinas/química , Técnicas In Vitro , Masculino , Estructura Molecular , Fosforilación/efectos de los fármacos , Fosfotirosina/metabolismo , Extractos Vegetales/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Conejos , Relación Estructura-ActividadRESUMEN
Three new prenylated isoflavones, 5,7-dihydroxy-6-(2''-hydroxy-3''-methylbut-3''-enyl)-4'-methoxylisoflavone (1), 5,4'-dihydroxy-6-(3''-methylbut-2''-enyl)-2'''-(4'''-hydroxy-4'''-methylethyl)-3'''-methoxydihydrofurano-[4''',5''';7,8]isoflavone (2), and 5,4'-dihydroxy-8-(3''-methylbut-2''-enyl)-2'''-(4'''-hydroxy-4'''-methylethyl)furano-[4''',5''';6,7]isoflavone (3), a benzylated dihydroflavonol, 5,7,4'-trihydroxy-8-p-hydroxybenzyldihydroflavonol (4), and eight known flavonoids (5-12) were isolated from the fruits of Cudrania tricuspidata. The structures of these compounds were determined on the basis of MS and (1)H and (13)C NMR spectroscopic data, including 2D NMR experiments. Compounds 2, 3, 6, 7, 8, 10, 11, and 12 inhibited LPS-induced nitric oxide production, with IC(50) values of 11.8-41.8 microM.
Asunto(s)
Derivados del Benceno/aislamiento & purificación , Isoflavonas/aislamiento & purificación , Moraceae/química , Plantas Medicinales/química , Derivados del Benceno/química , Derivados del Benceno/farmacología , Frutas/química , Concentración 50 Inhibidora , Isoflavonas/química , Isoflavonas/farmacología , Lipopolisacáridos/farmacología , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/metabolismo , Resonancia Magnética Nuclear BiomolecularRESUMEN
A new ent-abietane diterpenoid, 3alpha,6beta-dihydroxy-7,17-dioxo-ent-abieta-15(16)-ene (1), and three known ent-kaurane diterpenids, kamebacetal A (2), kamebakaurin (3), and excisanin A (4), and a known triterpenoid, ursolic acid (5), were isolated from the aerial parts of Isodon inflexus. Their chemical structures were determined by extensive analysis of spectroscopic data including 1D-and 2D-NMR experiments. All isolates (1-5) were evaluated for their potential to inhibit LPS-induced nitric oxide production in RAW264.7 cells. Of these, compounds 1-4 inhibited the production of NO with IC(50) values ranging from 1.0 to 26.5 microM.
Asunto(s)
Abietanos/química , Diterpenos/química , Isodon/química , Abietanos/aislamiento & purificación , Animales , Supervivencia Celular/efectos de los fármacos , Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Modelos Moleculares , Conformación Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Extractos Vegetales/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Sales de Tetrazolio , TiazolesRESUMEN
Five ent-kaurane diterpenoids, 6beta,7beta,14beta-trihydroxy-1alpha,19-diacetoxy-7alpha,20-epoxy- ent-kaur-16-en-15-one (1), 1alpha,6beta,7beta-trihydroxy-11alpha,19-diacetoxy-7alpha,20-epoxy-ent-kaur-16-en-15-one (2), 6-hydroxy-1alpha,19-diacetoxy-6,7-seco-ent-kaur-16-en-15-one-7,20-olide (3), 19-hydroxy-1alpha,6-diacetoxy-6,7-seco- ent-kaur-16-en-15-one-7,20-olide (4), and 6-aldehyde-1alpha,19-diacetoxy-6,7-seco- ent-kaur-16-en-15-one-7,20-olide (5), along with 10 known ent-kaurane diterpenoids, pseurata C (6), longikaurin C (7), effusanin C (8), longikaurin B (9), longikaurin D (10), effusanin D (11), excisanin B (12), lasiokaurin (13), megathyrin A (14), and loxothyrin A (15), were isolated from the aerial parts of Isodon japonicus. Their structures were determined on the basis of spectroscopic (1D-, 2D-NMR and MS) and chemical evidence. The isolates were evaluated for their inhibitory effects on LPS-induced production of nitric oxide in murine macrophage RAW264.7 cells.
Asunto(s)
Diterpenos de Tipo Kaurano/aislamiento & purificación , Isodon/química , Plantas Medicinales/química , Animales , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/farmacología , Corea (Geográfico) , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Estructura Molecular , Óxido Nítrico/metabolismo , Resonancia Magnética Nuclear BiomolecularRESUMEN
Two new melampolide-type sesquiterpene lactones, 8beta-epoxyangeloyloxy-9alpha-ethoxy-14-oxo-acanthospermolide (1) and 8beta-angeloyloxy-9alpha-ethoxy-14-oxo-acanthospermolide (2), were isolated from the leaves of yacon [Smallanthus sonchifolia (POEPP. et ENDL.) H. Robinson] along with eleven known melampolides, allo-schkuhriolide (3), enhydrin (4), polymatin A (5), fluctuanin (6), 8beta-angeloyloxy-9alpha-acetoxy-14-oxo-acanthospermolide (7), 8beta-angeloyloxy-14-oxo-acanthospermolide (8), 8beta-methacryloyloxymelampolid-14-oic acid methyl ester (9), uvedalin (10), polymatin B (11), 8beta-tigloyloxymelampolid-14-oic acid methyl ester (12), and sonchifolin (13). Their structures were established on the basis of spectroscopic evidence including 1D- and 2D-NMR experiments. All isolates were evaluated for inhibition of LPS-induced nitric oxide production in murine macrophage RAW 264.7 cells.
Asunto(s)
Asteraceae/química , Lactonas/química , Lactonas/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Óxido Nítrico/biosíntesis , Sesquiterpenos/química , Sesquiterpenos/farmacología , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Cristalografía por Rayos X , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Modelos Moleculares , Extractos Vegetales/análisis , Hojas de la Planta/química , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
We have previously reported that green tea catechins displayed a potent antithrombotic effect by inhibition of platelet aggregation. In the present study, the antiplatelet and antithrombotic activities of epigallocatechin gallate (EGCG), the major catechin derived from green tea, were extensively investigated. EGCG inhibited arterial thrombus formation and U46619-, collagen-, and arachidonic acid (AA)-induced washed rabbit platelet aggregation in a concentration-dependent manner, with IC50 values of 61 +/- 3, 85 +/- 4, and 99 +/- 4 microM, respectively. In line with the inhibition of collagen-induced platelet aggregation, EGCG revealed blocking of the collagen-mediated phospholipase (PL) Cgamma2 and protein tyrosine phosphorylation, and it caused concentration-dependent decreases of cytosolic calcium mobilization, AA liberation, and serotonin secretion. In addition, the platelet aggregation, intracellular Ca2+ mobilization, and protein tyrosine phosphorylation induced by thapsigargin, a Ca2(+)-ATPase pump inhibitor, were completely blocked by EGCG. Contrary to the inhibition of AA-induced platelet aggregation, EGCG failed to inhibit cyclooxygenase and thromboxane (TX) A2 synthase activities, but it concentration-dependently elevated AA-mediated PGD2 formation. In contrast, epigallocatechin (EGC), a structural analogue of EGCG lacking a galloyl group in the 3' position, slightly inhibited collagen-stimulated cytosolic calcium mobilization, but failed to affect other signal transductions as did EGCG in activated platelets and arterial thrombus formation. These results suggest that antiplatelet activity of EGCG may be attributable to its modulation of multiple cellular targets, such as inhibitions of PLCgamma2, protein tyrosine phosphorylation and AA liberation, and elevation of cellular PGD2 levels, as well as maintaining Ca2(+)-ATPase activity, which may underlie its beneficial effect on the atherothrombotic diseases.
Asunto(s)
Catequina/análogos & derivados , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Té/química , Animales , Ácido Araquidónico/metabolismo , ATPasas Transportadoras de Calcio/efectos de los fármacos , ATPasas Transportadoras de Calcio/metabolismo , Catequina/administración & dosificación , Catequina/farmacología , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Masculino , Fosfolipasa C gamma/efectos de los fármacos , Fosfolipasa C gamma/metabolismo , Fosforilación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Prostaglandina D2/metabolismo , Conejos , Ratas , Ratas Sprague-DawleyRESUMEN
Four new prenylated xanthones, cudratricusxanthones J-M (1-4), were isolated from the CH2Cl2-soluble extract of the root bark of Cudrania tricuspidata, along with four known prenylated xanthones, isocudraxanthone K (5), cudraxanthone C (6), cudratricusxanthone A (7), and cudraxanthone L (8), and three known prenylated flavonoids, cudraflavone A (9), cudraflavanone A (10), and cudraflavone B (11). The structures of compounds 1-4 were elucidated using spectroscopic methods. Cudratricusxanthone A (7), cudraflavanone A (10), and cudraflavone B (11) showed moderate inhibitory effects on mouse brain monoamine oxidase (MAO) with IC50 values of 88.3, 89.7, and 80.0 microM, respectively.
Asunto(s)
Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Moraceae/química , Plantas Medicinales/química , Xantonas/aislamiento & purificación , Animales , Encéfalo/enzimología , Ratones , Estructura Molecular , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacología , Corteza de la Planta/química , Raíces de Plantas/química , Xantonas/química , Xantonas/farmacologíaRESUMEN
Carnosic acid is a major phenolic diterpene derived from Rosmarinus officinalis and has been reported to have antioxidant, antibacterial, anticancer, antiobese and photoprotective activities. This study investigated the antiplatelet activity of carnosic acid. carnosic acid significantly inhibited collagen-, arachidonic acid-, U46619- and thrombin-induced washed rabbit platelet aggregation in a concentration-dependent manner, with IC50 values of 39+/-0.3, 34+/-1.8, 29+/-0.8 and 48+/-2.9 microM, respectively, while it failed to inhibit PMA-(a direct PKC activator) and ADP-induced platelet aggregation. In agreement with its antiplatelet activity, carnosic acid blocked collagen-, arachidonic acid-, U46619- and thrombin-mediated cytosolic calcium mobilization. accordingly, serotonin secretion and arachidonic acid liberation were also inhibited in a similar concentration-dependent manner. However, in contrast to the inhibition of arachidonic acid-induced platelet aggregation, carnosic acid had no effect on the formation of arachidonic acid-mediated thromboxane A2 and prostaglandin D2, thus indicating that carnosic acid has no effect on the cyclooxygenase and thromboxane A2 synthase activity. Overall, these results suggest that the antiplatelet activity of carnosic acid is mediated by the inhibition of cytosolic calcium mobilization and that carnosic acid has the potential of being developed as a novel antiplatelet agent.
Asunto(s)
Abietanos/farmacología , Extractos Vegetales/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Rosmarinus/química , Abietanos/química , Abietanos/aislamiento & purificación , Animales , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Calcio/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Inhibidores de Agregación Plaquetaria/química , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Conejos , RatasRESUMEN
As part of an ongoing search for plant-derived compounds that inhibit the activation of NF-kappaB, the methanol extract of the aerial parts of Isodon excisus was found to have significant inhibitory effects on the activation of NF-kappaB in murine macrophage RAW264.7 cells. Bioactivity-guided isolation of the extract yielded five new diterpenoids, excisusin A-E (1-5), along with seven known compounds, inflexarabdonin I (6), inflexarabdonin G (7), inflexin (8), inflexanin A (9), inflexanin B (10), inflexinol (11), and inflexarabdonin A (12). The structures were determined by analysis of the spectroscopic data including 2D NMR. All of the isolates were evaluated for their inhibitory effects on LPS-induced NF-kappaB activation and nitric oxide production in RAW264.7 cells.
Asunto(s)
Diterpenos de Tipo Kaurano , Isodon/química , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico/antagonistas & inhibidores , Plantas Medicinales/química , Animales , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/aislamiento & purificación , Diterpenos de Tipo Kaurano/farmacología , Corea (Geográfico) , Ratones , Conformación Molecular , Estructura MolecularRESUMEN
Seven flavonoids were isolated from the whole plants and fruits of Cayratia japonica through the activity-guided isolation of a methanol extract using a monoamine oxidase (MAO) inhibition assay as a monitor. The chemical structures of the isolates were assigned as apigenin-7-O-beta-D-glucuronopyranoside (1), apigenin (2), luteolin (3), luteolin-7-O-beta-D-glucopyranoside (4), (+)-dihydroquercetin (taxifolin) (5), (+)-dihydrokaempferol (aromadendrin) (6) and quercetin (7). Among the isolated compounds, flavones such as apigenin (2) and luteolin (3), as well as the flavonol, quercetin (7) showed potent inhibitory effects against the MAO activity with IC50 values of 6.5, 22.6, and 31.6 microM, respectively. However, the flavone glycosides, apigenin-7-O-beta-D-glucuronopyranoside (1) and luteolin-7-O-beta-D-glucopyranoside (4), showed mild MAO inhibition (IC50 values: 81.7 and 118.6 microM, respectively). The flavanonol derivatives, taxifolin (5) and aromadendrin (6), also showed weak inhibition (IC50 values: 154.7 and 153.1 microM, respectively). Furthermore, quercetin (7) had a more potent inhibitory effect on MAO-A (IC50 value: 2.8 microM) than MAO-B (IC50 value: 90.0 microM). Apigenin (2) and luteolin (3) also preferentially inhibited MAO-A (IC50 values: 1.7 and 4.9 microM, respectively) compared with MAO-B (IC50 values: 12.8 and 59.7 microM, respectively).
Asunto(s)
Ansiolíticos/farmacología , Antidepresivos/farmacología , Encéfalo/efectos de los fármacos , Flavonoides/farmacología , Inhibidores de la Monoaminooxidasa/farmacología , Vitaceae , Animales , Ansiolíticos/química , Ansiolíticos/aislamiento & purificación , Antidepresivos/química , Antidepresivos/aislamiento & purificación , Bioensayo/métodos , Encéfalo/enzimología , Fraccionamiento Químico/métodos , Flavonoides/química , Flavonoides/aislamiento & purificación , Técnicas In Vitro , Isoenzimas , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Estructura Molecular , Monoaminooxidasa/metabolismo , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Extractos Vegetales/química , Solventes/química , Relación Estructura-ActividadRESUMEN
The antithrombotic and antiplatelet activities of Korean red ginseng extract (KRGE) were examined on rat carotid artery thrombosis in vivo and platelet aggregation in vitro and ex vivo. The KRGE significantly prevented rat carotid arterial thrombosis in vivo in a dose-dependent manner. Administration of the KRGE to rats significantly inhibited adenosine diphosphate (ADP)- and collagen-induced platelet aggregation ex vivo, although it failed to prolong coagulation times such as activated partial thromboplastin and prothrombin time indicating that the antithrombotic effect of the red ginseng may be due to its antiplatelet aggregation rather than anticoagulation effect. In line with the above observations, the red ginseng inhibited the U46619-, arachidonic acid-, collagen- and thrombin-induced rabbit platelet aggregations in vitro in a concentration-dependent manner, with IC(50) values of 390 +/- 15, 485 +/- 19, 387 +/- 11 and 335 +/- 15 microg/ml, respectively. Consistently, serotonin secretion was also inhibited by ginseng in the same pattern. These results suggest that the red ginseng has a potent antithrombotic effect in vivo, which may be due to the antiplatelet rather than the anticoagulation activity, and the red ginseng intake may be beneficial for individuals with high risks of thrombotic and cardiovascular diseases.
Asunto(s)
Trombosis de las Arterias Carótidas/prevención & control , Fibrinolíticos/farmacología , Panax , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Animales , Pruebas de Coagulación Sanguínea , Relación Dosis-Respuesta a Droga , Fibrinolíticos/administración & dosificación , Fibrinolíticos/química , Técnicas In Vitro , Corea (Geográfico) , Masculino , Tiempo de Tromboplastina Parcial , Extractos Vegetales , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/química , Tiempo de Protrombina , Conejos , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo , Trombosis/prevención & controlRESUMEN
A methylene chloride soluble fraction of the fruits of Cudrania tricuspidata significantly inhibited the mouse brain monoamine oxidase (MAO). Three known prenylated isoflavones were isolated and identified by activity-guided fractionation. Gancaonin A (1), 4'-O-methylalpinumisoflavone (2), and alpinumisoflavone (3) inhibited MAO activity in a concentration-dependent manner with IC50 values of 19.4, 23.9, and 25.8 microM, respectively. Of these, gancaonin A (1) showed a selective and potent inhibitory effect against MAO-B (IC50 0.8 microM) than MAO-A (IC50 >800 microM). The kinetic analysis using Lineweaver-Burk plots indicated that gancaonin A (1) competitively inhibited MAO-B.