RESUMEN
The roots of Erythrina lysistemon, growing in Egypt, yielded 24 flavonoid compounds, including 17 pterocarpans, two isoflavanones, one flavanone, two isoflavans, one 2-arylbenzofuran, and an isoflava-3-ene. Nine pterocarpans have not been reported previously (7-9, 11-14, 19, and 20), and 11 are reported here for the first time from this species. Structures were established using HRESIMS, NMR, and circular dichroism techniques. Selected compounds were tested for their ability to block the growth of human retinal endothelial cells and antiangiogenic activity in vitro. The isoflavonoids 5 and 6, and the pterocarpans 1, 2, 4, 20, and 22 demonstrated selective antiproliferative activities on endothelial cells compared to a nonendothelial cell type, with concentration-dependent antiangiogenic effects in vitro against HRECs, a cell type relevant to neovascular eye diseases.
Asunto(s)
Erythrina , Pterocarpanos , Humanos , Flavonoides/farmacología , Erythrina/química , Pterocarpanos/farmacología , Pterocarpanos/química , Células Endoteliales/metabolismo , Extractos Vegetales/farmacologíaRESUMEN
A phytochemical investigation of the roots of Citrus × paradisi Macfad. (Rutaceae) led to the isolation of two new compounds, namely 1-formyl-5-hydroxy-N-methylindolin-1-ium (1) and decyloxycleomiscosin D (2), along with ten known compounds: 1,1-dimethylpyrrolidin-1-ium-2-carboxylate (3), furan-2,3-diol (4), 5-methoxyseselin (5), umbelliferone (6), scopoletin (7), citracridone I (8), citracridone II (9), citracridone III (10), limonin (11) and lupeol (12). The structures were determined through the comprehensive spectroscopic analysis of 1D and 2D NMR and EI- and ESI-MS, as well as a comparison with the published data. Notably, compounds 3 and 4 from the genus Citrus are reported here for the first time. In addition, the MeOH extract of the roots and compounds 1-7 were screened against the human adenocarcinoma alveolar basal epithelial cell line A549 and the Caucasian prostate adenocarcinoma cell line PC3 using the MTT assay. While the extract showed significant activity, with IC50 values of 35.2 and 38.1 µg/mL, respectively, compounds 1-7 showed weak activity, with IC50 values of 99.2 to 250.2 µM and 99.5 to 192.7 µM, respectively.
Asunto(s)
Adenocarcinoma , Citrus paradisi , Citrus , Rutaceae , Masculino , Humanos , Rutaceae/química , Extractos Vegetales/química , Alcaloides Indólicos/análisis , Raíces de Plantas/química , Estructura MolecularRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The Zulu and Xhosa people of South Africa use the stem bark of Cassipourea flanaganii as a skin-lightning cosmetic. AIM OF THE STUDY: To isolate and identify compounds responsible for the skin lightning properties from the stem bark of Cassipourea flanaganii and to evaluate their cytotoxicity towards skin cells. MATERIALS AND METHODS: Extracts from the stem bark of Cassipourea flanaganii were isolated using chromatographic methods and structures were determined using NMR, IR and MS analysis. The tyrosinase inhibitory activity and the ability to inhibit the production of melanin were determined using human primary epidermal melanocyte cells. Cytoxicity was established using the same melanocytes and a neutral red assay. RESULTS: One previously undescribed compound, ent-atis-16-en-19-al (1) along with the known ent-atis-16-en-19-oic acid (2), ent-atis-16-en-19-ol (3), ent-kaur-16-en-19-oic acid (4), ent-kaur-16-en-19-al (5), ent-manoyl oxide (6), guinesine A (7), guinesine B (8), guinesine C (9), lichenxanthone (10), 2,4-dihydroxy-3,6-dimethyl benzoic acid methyl ester (11), lynoside (12), lupeol (13), ß-amyrin (14), docosyl ferulate (15), stigmasterol, sitosterol and sitosterol-O-glucoside were isolated in this investigation. An impure fraction containing compound 3 was acetylated to obtain 19-acetoxy-ent-atis-16-ene (3a). Compounds 10 and 11 are usually isolated from lichen, hence they are possible contaminants of lichen harvested with the bark. Compounds 1, 3a, 5-14 were not significantly cytotoxic to the primary epidermal melanocyte cells (P > 0.05) when compared to the negative and positive controls (DMSO, 0.1% and hydrogen peroxide, 30 wt% in water). Inhibition of tyrosinase was significantly greater with respect to the negative control (P < 0.001) for compounds 3a, 5-8 and 9-10 at 10 µM and for compounds 5-8 and 9-10 at 100 µM. Compared to hydroquinone (the positive control) at 10 µM, the level of inhibition was comparable or to that of compounds 3a, 5, 6, and 8-10 at 10 µM, with 9 and 10 showing a greater level of inhibition. Inhibition of melanin was both concentration and time dependent for all compounds tested with higher melanin content at 24 h compared to 48 h s and at 10 mM compared to100 mM at both time points; melanin content was significantly lower for hydroquinone at both time points and concentrations. CONCLUSIONS: Compounds 1, 5-14, isolated from Cassipourea flanaganii and the derivative 3a showed low cytotoxicity. All compounds had a clear time and concentration dependent effect on melanin content which did not appear to be dependent on their inhibition of tyrosinase.
Asunto(s)
Melaninas/antagonistas & inhibidores , Melanocitos/efectos de los fármacos , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , Rhizophoraceae , Preparaciones para Aclaramiento de la Piel/farmacología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Melaninas/metabolismo , Melanocitos/metabolismo , Monofenol Monooxigenasa/metabolismo , Corteza de la Planta , Extractos Vegetales/aislamiento & purificación , Tallos de la Planta , Preparaciones para Aclaramiento de la Piel/aislamiento & purificaciónRESUMEN
Five compounds, 3,4'-dihydroxy-3',5,5'-trimethoxydihydrostilbene, 1: ; 3,4'-ihydroxy-3',5'-dimethoxydihydrostilbene, 2: ; 3,4'-dihydroxy-5,5'-dimethoxydihydrostilbene, 3: ; 9,10-dihydro-2,7-dihydroxy-4,6-dimethoxyphenanthrene, 4: ; and the previously unreported 1,2,6,7-tetrahydroxy-4-methoxyphenanthrene, 5: were isolated from the South American orchid, Brasiliorchis porphyrostele. An in-depth analysis of their vascular effects was performed on in vitro rat aorta rings and tail main artery myocytes. Compounds 1: â-â4: were shown to possess vasorelaxant activity on rings pre-contracted by the α 1 receptor agonist phenylephrine, the CaV1.2 stimulator (S)-(-)-Bay K 8644, or depolarized with high K+ concentrations. However, compound 5: was active solely on rings stimulated by 25 mM but not 60 mM K+. The spasmolytic activity of compounds 1: and 4: was significantly affected by the presence of an intact endothelium. The KATP channel blocker glibenclamide and the KV channel blocker 4-aminopyridine significantly antagonized the vasorelaxant activity of compounds 4: and 1: , respectively. In patch-clamp experiments, compounds 1: â-â4: inhibited Ba2+ current through CaV1.2 channels in a concentration-dependent manner, whereas neither compound 4: nor compound 1: affected K+ currents through KATP and KV channels, respectively. The present in vitro, comprehensive study demonstrates that Brasiliorchis porphyrostele may represent a source of vasoactive agents potentially useful for the development of novel antihypertensive agents that has now to be validated in vivo in animal models of hypertension.
Asunto(s)
Fenantrenos , Estilbenos , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico , Animales , Músculo Liso , Ratas , Vasodilatación , VasodilatadoresRESUMEN
BACKGROUND: Homoisoflavonoids have been shown to have potent anti-proliferative activities in endothelial cells over other cell types and have demonstrated a strong antiangiogenic potential in vitro and in vivo in animal models of ocular neovascularization. Three species of Rhodocodon (Scilloideaea subfamily of the Asparagaceae family), endemic to Madagascar, R. cryptopodus, R. rotundus and R. cyathiformis, were investigated. PURPOSE: To isolate and test homoisoflavonoids for their antiangiogenic activity against human retinal microvascular endothelial cells (HRECs), as well as specificity against other ocular cell lines. METHODS: Plant material was extracted at room temperature with EtOH. Compounds were isolated using flash column chromatography and were identified using NMR and CD spectroscopy and HRESIMS. Compounds were tested for antiproliferative effects on primary human microvascular retinal endothelial cells (HRECs), ARPE19 retinal pigment epithelial cells, 92-1 uveal melanoma cells, and Y79 retinoblastoma cells. HRECs exposed to compounds were also tested for migration and tube formation ability. RESULTS: Two homoisoflavonoids, 3S-5,7-dihydroxy-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone (1) and 3S-5,7-dihydroxy-(4'-hydroxy-3'-methoxybenzyl)-4-chromanone (2), were isolated along with four bufadienolides. Compound 1 was found to be non-specifically antiproliferative, with GI50 values ranging from 0.21-0.85 µM across the four cell types, while compound 2 showed at least 100-fold specificity for HRECs over the other tested cell lines. Compound 1, with a 3S configuration, was 700 times more potent that the corresponding 3R enantiomer recently isolated from a Massonia species. CONCLUSION: Select homoisoflavonoids have promise as antiangiogenic agents that are not generally cytotoxic.
Asunto(s)
Asparagaceae/química , Bufanólidos/química , Isoflavonas/química , Isoflavonas/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Humanos , Vasos Retinianos/citologíaRESUMEN
The Hyacinthaceae family (sensu APGII), with approximately 900 species in around 70 genera, plays a significant role in traditional medicine in Africa as well as across Europe and the Middle and Far East. The dichloromethane extract of the bulbs of Massonia pustulata (Hyacinthaceae sensu APGII) yielded two known homoisoflavonoids, (R)-5-hydroxy-3-(4-hydroxybenzyl)-7-methoxy-4-chromanone 1: and 5-hydroxy-3-(4-hydroxybenzyl)-7-methoxy-4-chromone 2: and four spirocyclic nortriterpenoids, eucosterol 3: , 28-hydroxyeucosterol 4: and two previously unreported triterpenoid derivatives, (17S,23S)-17α,23-epoxy-3ß,22ß,29-trihydroxylanost-8-en-27,23-olide 5: , and (17S, 23S)-17α,23-epoxy-28,29-dihydroxylanost-8-en-3-on-27,23-olide 6: . Compounds 1, 2, 3: , and 5: were assessed for cytotoxicity against CaCo-2 cells using a neutral red uptake assay. Compounds 1, 2: , and 5: reduced cell viability by 70% at concentrations of 30, 100, and 100 µM, respectively. Massonia bifolia yielded three known homoisoflavonoids, (R)-(4'-hydroxy)-5-hydroxy-7-methoxy-4-chromanone 1: , (R)-(4'-hydroxy)-5,7-dihydroxy-4-chromanone 7: and (R)-(3'-hydroxy-4'-methoxy)-5,7-dihydroxy-4-chromanone 9: , two previously unreported homoisoflavonoids, (E)-3-benzylidene-(3',4'-dihydroxy)-5-hydroxy-7-methoxy-4-chromanone 8: and (R)-(3',4'-dihydroxy)-5-hydroxy-7-methoxy-4-chromanone 10,: and a spirocyclic nortriterpenoid, 15-deoxoeucosterol 11: . Compounds 1, 1AC, 7, 8, 9,: and 10: were screened for antiangiogenic activity against human retinal microvascular endothelial cells. Some compounds showed dose-dependent antiproliferative activity and blocked endothelial tube formation, suggestive of antiangiogenic activity.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Asparagaceae/química , Flavonoides/farmacología , Triterpenos/farmacología , Inhibidores de la Angiogénesis/efectos adversos , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/aislamiento & purificación , Células CACO-2 , Células Endoteliales , Flavonoides/efectos adversos , Flavonoides/química , Flavonoides/aislamiento & purificación , Humanos , Isoflavonas/efectos adversos , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacología , Estructura Molecular , Triterpenos/efectos adversos , Triterpenos/química , Triterpenos/aislamiento & purificaciónRESUMEN
BACKGROUND: Plant extracts might provide sustainable alternatives to copper fungicides, which are still widely used despite their unfavourable ecotoxicological profile. Larch bark extract and its constituents, larixyl acetate and larixol, have been shown to be effective against grapevine downy mildew (Plasmopara viticola) under semi-controlled conditions. The aim of this study was to reduce the gap between innovation and the registration of a marketable product, namely to develop scalable extraction processes and to evaluate and optimise the performance of larch extracts under different conditions. RESULTS: Toxicologically and technically acceptable solvents like ethanol were used to extract the active compounds larixyl acetate and larixol from bark in sufficient amounts and their combined concentration could be increased by up to 39% by purification steps. The combined concentration of larixyl acetate and larixol from larch turpentine could be increased by up to 66%. The Minimal Inhibitory Concentration (MIC100 ) against P. viticola in vitro (6-23 µg mL-1 ) and the Effective Concentration (EC50 ) in planta under semi-controlled conditions (0.2-0.4 mg mL-1 ) were promising compared with other plant extracts. In vineyards, efficacies of larch extracts reached up to 68% in a stand-alone strategy and 84% in low-copper strategies. CONCLUSION: Larch extracts represent valid candidates for copper reduction in organic vineyards, and their development into a sustainable plant protection product might be feasible. © 2017 Society of Chemical Industry.
Asunto(s)
Diterpenos/farmacología , Fungicidas Industriales/farmacología , Oomicetos/efectos de los fármacos , Enfermedades de las Plantas/prevención & control , Vitis , Clima , Grecia , Italia , Larix/química , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Suiza , Vitis/crecimiento & desarrollo , Vitis/microbiologíaRESUMEN
The genus Rhodocodon (Hyacinthaceae sensu APG II) is endemic to Madagascar, and its phytochemistry has not been described previously. The phytochemistry of three species in this genus has been investigated, and eight compounds, including three bufadienolides (compounds 1, 4, and 5), a norlignan (2), and four homoisoflavonoids (compounds 3 and 6-8), have been isolated and identified. Compounds 1-3 and 6-8 have not been described previously. The COX-2 inhibitory activity of compound 6 and compound 7 acetate (compound 7A) was investigated on isolated colorectal cancer cells. Compounds 6 and 7A inhibited COX-2 by 10% and 8%, respectively, at a concentration of 12.5 µM compared to 12% for 1 mM aspirin (the positive control).
Asunto(s)
Asparagaceae/química , Bufanólidos/aislamiento & purificación , Bufanólidos/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacología , Lactonas/aislamiento & purificación , Lactonas/farmacología , Lignanos/aislamiento & purificación , Lignanos/farmacología , Liliaceae/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Bufanólidos/química , Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/aislamiento & purificación , Humanos , Isoflavonas/química , Lactonas/química , Lignanos/química , Madagascar , Estructura Molecular , Fitoquímicos , Extractos Vegetales/químicaRESUMEN
The roots of the endangered medicinal plant Croton megalocarpoides collected in Kenya were investigated and twenty-two compounds isolated. Among them were twelve new ent-clerodane (1-12) and a new abietane (13) diterpenoids, alongside the known crotocorylifuran (4 a), two known abietane and four known ent-trachylobane diterpenoids, and the triterpenoids, lupeol and acetyl aleurotolic acid. The structures of the compounds were determined using NMR, HRMS and ECD. The isolated compounds were evaluated against a series of microorganisms (fungal and bacteria) and also against Plasmodium falciparum, however no activity was observed.
Asunto(s)
Abietanos/aislamiento & purificación , Croton/química , Diterpenos de Tipo Clerodano/aislamiento & purificación , Abietanos/química , Diterpenos de Tipo Clerodano/química , Especies en Peligro de Extinción , Kenia , Estructura Molecular , Raíces de Plantas/química , Plantas Medicinales/químicaRESUMEN
Phytochemical analyses of the bulbs of Eucomis vandermerwei and E. zambesiaca yielded homoisoflavonoids and triterpenoid derivatives. A new (17S*23S*)-epoxy-3ß,15ß,29-trihydroxy-27-norlanost-8-en-24-one) was isolated from E. zambesiaca. Resnova humifusa yielded homoisoflavonoids, and a tetrahydropyran derivative, 2-methyl-3-(4S*,5R *,7S*-trihydroxy-8S*-hydroxymethyltetrahydro-6H-4-pyranyl)-2-propenoic acid. All compounds were assayed for COX-2 inhibition of cyclooxygenase; 3,5,7-trihydroxy-3-(4'-methoxybenzyl)-4-chromanone was found to have significant activity.
Asunto(s)
Liliaceae/química , Triterpenos/aislamiento & purificación , Raíces de Plantas/química , Triterpenos/químicaRESUMEN
From the stem bark and leaves of Sclerocroton integerrimus, eight compounds, including 17-hydroxy-ent-pimara-8(14),15-dien-3-one (1), were isolated. The structures of the compounds were determined on the basis of spectroscopic analysis. The absolute configuration of 17-hydroxy-ent-pimara-8(14),15-dien-3-one was confirmed from electronic circular dichroism studies.
Asunto(s)
Abietanos/química , Euphorbiaceae/química , Extractos Vegetales/química , Hojas de la Planta/química , Dicroismo Circular , Estructura Molecular , Tallos de la Planta/químicaRESUMEN
The efficient and effective selection of appropriate plants for investigative purposes in a drug discovery program is of crucial importance for a successful outcome. A variety of approaches have been used by researchers with varying levels of success. A variety of different approaches to plant selection are discussed, including the ethnomedicinal approach, some ecological approaches, and the use of combinatorial and computational methodologies.
Asunto(s)
Descubrimiento de Drogas/métodos , Extractos Vegetales , Plantas , Humanos , Extractos Vegetales/uso terapéuticoRESUMEN
The Hyacinthaceae (sensu APGII), with approximately 900 species in about 70 genera, can be divided into three main subfamilies, the Hyacinthoideae, the Urgineoideae and the Ornithogaloideae, with a small fourth subfamily the Oziroëoideae, restricted to South America. The plants included in this family have long been used in traditional medicine for a wide range of medicinal applications. This, together with some significant toxicity to livestock has led to the chemical composition of many of the species being investigated. The compounds found are, for the most part, subfamily-restricted, with homoisoflavanones and spirocyclic nortriterpenoids characterising the Hyacinthoideae, bufadienolides characterising the Urgineoideae, and cardenolides and steroidal glycosides characterising the Ornithogaloideae. The phytochemical profiles of 38 genera of the Hyacinthaceae will be discussed as well as any biological activity associated with both crude extracts and compounds isolated. The Hyacinthaceae of southern Africa were last reviewed in 2000 (T. S. Pohl, N. R. Crouch and D. A. Mulholland, Curr. Org. Chem., 2000, 4, 1287-1324; ref. 1); the current contribution considers the family at a global level.
Asunto(s)
Liliaceae , Bufanólidos/química , Liliaceae/química , Liliaceae/genética , Liliaceae/metabolismo , Estructura MolecularRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The stem bark of Garcinia livingstonei is used traditionally as a skin lightening agent. AIM OF THE STUDY: To isolate and identify compounds responsible for the observed skin lightening activity of Garcinia livingstonei and to evaluate their cytotoxicity. MATERIALS AND METHODS: Constituents of the stem bark and fruits of Garcinia livingstonei were isolated using chromatographic techniques and structures were determined using 1D and 2D NMR and MS analysis. MeWo cells were used to evaluate the cytotoxicity and impact on melanin levels of extracts and compounds isolated, in vitro. RESULTS: Twelve known compounds, morelloflavone (1), morelloflavone-7â³-sulphate (2), guttiferone A (3), sargaol (4), isojacareubin (5), 6-deoxyisojacareubin (6) and in addition to the common triterpenoids, betulin, betulin aldehyde, lupeol, lupenone, euphol and stigmasterol were isolated in this investigation. Morelloflavone, morelloflavone-7â³-sulphate and sargaol, were found to be considerably less cytotoxic and more effective as skin lightening agents than hydroquinone. CONCLUSIONS: A range of compounds was isolated from the stem bark and fruit of Garcinia livingstonei. Although the bark extract contained the cytotoxic guttiferone A, it was found to be less toxic than hydroquinone, and morelloflavone, the 7â³-sulphate derivative and sargaol show potential for development as depigmentation/skin lightening agents.
Asunto(s)
Garcinia , Melaninas/metabolismo , Extractos Vegetales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Frutas , Humanos , Corteza de la PlantaRESUMEN
The bulbs of Ledebouria socialis (Hyacinthaceae) yielded the benzocyclobutene homoisoflavonoid, (R)-2',5-dihydroxy-3',4',7-trimethoxyspiro{2H-1-benzopyran-3-(4H)-9-bicyclo[4.2.0]octa[1,3,5]triene}-4-one, socialinone (1). Ledebouria ovatifolia yielded (2ε,3R)-2,5-dihydroxy-7-methoxyspiro[2H-1-benzopyran-3(4H), 5'(6'H)-cyclobuta[f][1,3]benzodioxol]-4-one (2) and the homoisoflavanone, (E)-3-(3',4'-dihydroxybenzylidene)-5,7-dihydroxychroman-4-one, ovatifolionone (5), the dihydrochalcone, 4,4'-dihydroxy-2',6'-dimethoxydihydrochalcone (3), and xanthone, 1,6-dihydroxy-2,3,5-trimethoxy-8-methyl-9H-xanthen-9-one (4) along with 21 known compounds. Structures were determined using spectroscopic techniques. The anti-inflammatory activities of the homoisoflavonoids and xanthones isolated were evaluated against cyclooxygenase-1 and -2 isoenzymes. (R)-3-(3',4'-Dihydroxybenzyl)-7-hydroxy-5-methoxychroman-4-one (7), (E)-3-(3',4'-dihydroxybenzylidene)-7-hydroxy-5-methoxychroman-4-one (10), 1,3,6-trihydroxy-2-methoxy-8-methylxanthen-9-one (6) and ovatifolionone acetate (5Ac) exhibited significant activity against cyclooxygenase-2 at <10µM.
Asunto(s)
Inhibidores de la Ciclooxigenasa 2/farmacología , Isoflavonas/farmacología , Liliaceae/química , Extractos Vegetales/farmacología , Xantonas/farmacología , África Austral , Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/aislamiento & purificación , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Raíces de Plantas/química , Xantonas/química , Xantonas/aislamiento & purificaciónRESUMEN
Chemotherapeutics represent the main approach for the treatment of leukemia. However, the occurrence of adverse side effects and the complete lack of effectiveness in some cases make it necessary to develop new drugs. As part of our screening program to evaluate the potential chemotherapeutic effect of natural coumarins, we investigated the anti-leukemic activities of a series of six prenylated coumarins isolated from the stem bark of Toddalia asiatica (Rutaceae). Among these, 6-(3-methyl-2-butenyl)-5,7-dimethoxycoumarin (toddaculin) displayed the most potent cytotoxic and anti-proliferative effects in U-937 cells. To determine whether these effects resulted from induction of cell death or differentiation, we further evaluated the expression of several apoptosis and maturation markers. Interestingly, while toddaculin at 250 µM was able to induce apoptosis in U-937 cells, involving decreased phosphorylation levels of ERK and Akt, 50 µM toddaculin exerted differentiating effects, inducing both the capacity of U-937 cells to reduce NBT and the expression of differentiation markers CD88 and CD11b, but no change in p-Akt or p-ERK levels. Taken together, these findings indicate that toddaculin displays a dual effect as a cell differentiating agent and apoptosis inducer in U-937 cells, suggesting it may serve as a pharmacological prototype for the development of novel anti-leukemic agents.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Cumarinas/farmacología , Leucemia/patología , Rutaceae/química , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cumarinas/química , Regulación hacia Abajo/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Leucemia/tratamiento farmacológico , Leucemia/metabolismo , MAP Quinasa Quinasa 4/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Four triterpenoids isolated from the leaves of Fadogia tetraquetra var. tetraquetra, 3beta-hydroxy-11alpha, 12alpha-epoxyoleanan-28,13beta-olide (1), 3beta-hydroxyurs-11-en-28,13beta-olide (2), oleanolic acid (3), and ursolic acid (4), were evaluated for their antiviral and antibacterial properties. Compound 4 showed potent activity against the Semliki Forest virus with an IC50 of 14.7 microM, but was also found to be significantly cytotoxic (68% reduction in cell viability after 24 hours exposure at 50 microM) towards baby hamster kidney (BHK21) host cells. A viability assay on the mammalian human hepatocellular carcinoma (Huh-7) cell line showed no significant effects on intracellular ATP content after 48 hours exposure to compounds 1-4 at this concentration. Compound 4 also inhibited Staphylococcus aureus (MIC 12.5 microM), but was inactive against Enterobacter aerogenes, Escherichia coli, and Pseudomonas aeruginosa. Compounds 1-3 were inactive against all tested bacterial strains at 50 microM concentration.
Asunto(s)
Antibacterianos/aislamiento & purificación , Antivirales/aislamiento & purificación , Rubiaceae/química , Triterpenos/aislamiento & purificación , Animales , Antibacterianos/química , Antivirales/química , Línea Celular/efectos de los fármacos , Cricetinae , Humanos , Lactonas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Ácido Oleanólico/química , Hojas de la Planta/química , Triterpenos/química , Ácido UrsólicoRESUMEN
The stem bark of Croton gratissimus (Euphorbiaceae) yielded four cembranolides, including the first reported example of a 2,12-cyclocembranolide, (+)-[1R*,2S*,7S*,8S*,12R*]-7,8-epoxy-2,12-cyclocembra-3E,10Z-dien-20,10-olide, whose structure was confirmed by means of single crystal X-ray analysis. This compound showed moderate activity against the PEO1 and PEO1TaxR ovarian cancer cell lines.
Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Croton/química , Diterpenos/aislamiento & purificación , Plantas Medicinales/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Corteza de la Planta/química , Tallos de la Planta/química , Sudáfrica , EstereoisomerismoRESUMEN
The vasorelaxing effect of isolates (compounds 1, 2, 3, and 4 (homoisoflavanones), compound 5 (sesquiterpenoid), compounds 6 and 7 (bufadienolides)) from the South African Hyacinthaceae has been assessed using rat aortic ring preparations. Compounds 2, 3, and 4 inhibited the tonic contraction induced by both 60 mM K(+) (K60) and phenylephrine, compound 3 being the most potent. Compounds 5, 6, and 7 caused a modest concentration-dependent relaxation, whereas compound 1 was ineffective. Under K25- or K60-induced depolarization, compound 3 displayed antispasmodic effects not reversed by tetraethylammonium. Under precontraction induced with phenylephrine, compound 3 shifted to the left the concentration-relaxation curves of either isoprenaline or sodium nitroprusside. 1 H-[1,2,4] oxidazolol [4,3-a] quinoxalin-1-one shifted to the right the concentration-relaxation curve of compound 3, while 3'-isobutyl-1-methylxanthine had no effect. In the absence of extracellular Ca(2+), compound 3 (estimated pIC50 = 4.66) and ryanodine reduced the response to phenylephrine. Phenylephrine-stimulated influx of extracellular Ca(2+) was markedly reduced when tissues were pretreated with compound 3 (pIC50 = 5.14) or nifedipine, but stimulated by ryanodine. Compound 3 partially antagonized the contraction induced by phorbol 12-myristate-13-acetate. To our knowledge, this has been the first account describing the vasodilating activity of homoisoflavonoids: compound 3 proved an effective vasorelaxing agent, partly acting via the activation of soluble guanylyl cyclase.
Asunto(s)
Guanilato Ciclasa/metabolismo , Isoflavonas/farmacología , Liliaceae/química , Músculo Liso Vascular/efectos de los fármacos , Vasodilatadores/farmacología , Animales , Aorta/efectos de los fármacos , Aorta/fisiología , Bufanólidos/química , Bufanólidos/aislamiento & purificación , Bufanólidos/farmacología , Activación Enzimática , Técnicas In Vitro , Activación del Canal Iónico , Isoflavonas/química , Isoflavonas/aislamiento & purificación , Masculino , Relajación Muscular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Fenilefrina/farmacología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Canales de Potasio/fisiología , Compuestos de Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Sudáfrica , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacología , Vasoconstrictores/farmacología , Vasodilatadores/química , Vasodilatadores/aislamiento & purificaciónRESUMEN
Antibacterial bioassay-guided fractionation of an ethyl acetate root extract of Terminalia sericea led to the isolation of anolignan B. The isolated compound was further tested for anti-inflammatory activity using the cyclooxygenase enzyme assays (COX-1 and COX-2) and for potential mutagenic effects using the Ames test. In the antibacterial test, anolignan B showed activity against both Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration values obtained (MIC) ranged from 3.8 microg/ml against Bacillus subtilis (Gram-positive) to 31 microg/ml against Escherichia coli (Gram-negative). In the anti-inflammatory assays, anolignan B showed activity against both COX-1 (IC(50) = 1.5 mM) and COX-2 (IC(50) = 7.5 mM) enzymes. No potential mutagenic effects were observed in the Salmonella microsome assay (TA98). Isolation of anolignan B from Terminalia sericea as well as the antibacterial and anti-inflammatory activities observed in this study has not been reported previously.