RESUMEN
(25R)-spirost-5-en-3ß-ol, also known as diosgenin (DSG), exerts antiproliferative activity on diverse cell lines, induces apoptosis, and acts as a chemopreventative agent. However, the relationship between DSG glycosides and apoptotic, necrotic, and antiproliferative activity remains unclear. It is in this regard that we report the antiproliferative, necrotic, and apoptotic activities of DSG and its glycoside derivatives: (25R)-spirost-5-en-3ß-yl O-ß-D-glucopyranoside (3GD), (25R)-spirost-5-en-3ß-yl O-α-L-rhamnopyranosyl-(1 â 4)-ß-D-glucopyranoside (3GRD); and (25R)-spirost-5-en-3ß-yl O-α-L-rhamnopyranosyl-(1 â 2)-O-[α-L-rhamnopyranosyl-(1 â 4)]-ß-D-glucopyranoside), also known as dioscin (DSC), in in vitro assays of cervical HeLa and CaSki cancer cells. The results demonstrated that DSG glycosidic derivatives preserved their antiproliferative activity. However, in both cancer cell lines, 3GD and 3GRD were less potent than DSG, while DSC was more potent than DSG. With respect to necrotic activity, all tested compounds showed no or low activity on the two cervical cancer cell lines. Regarding apoptosis, the results showed that DSG glycosides were better apoptosis-inducers than DSG, suggesting that glucose and rhamnose residues play a central role in enhancing the apoptotic activity of DSG. Finally, DSG and its glycosidic derivatives were shown to affect the proliferative potential of lymphocytes (non-tumour cells) to a lesser extent than cancer cells, suggesting that these compounds have selective action. In conclusion, the results indicate that DSG and its glycosidic derivatives are promising anticancer compounds since they are compounds with low necrotic activity and selective action.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Diosgenina/análogos & derivados , Diosgenina/farmacología , Glucósidos/farmacología , Neoplasias del Cuello Uterino/patología , Caspasas/metabolismo , Proliferación Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Glicosilación , Células HeLa , Humanos , Necrosis/inducido químicamenteRESUMEN
The title steroid, [(25R)-spirost-4-en-3,6-dione, C27H38O4], is obtained by oxidation of diosgenin, using the Jones reagent (CrO3/H2SO4). The crystal structure was previously reported in space group P212121, but nonetheless with the wrong absolute configuration and omitting positions for H atoms [Rajnikant et al. (2000 â¸). Mol. Cryst. Liq. Cryst. Sci. Technol. Sect. C, 12, 101-110]. The diffraction data set reported herein is for a second polymorph in the same space group, as evidenced by simulated powder patterns. Both forms are characterized by a similar ortho-rhom-bic unit cell, and a similar arrangement of the mol-ecules in the crystal structure. However, the conformation of the A/B rings in the steroid nucleus is slightly modified, leading to the observed polymorphism.
RESUMEN
We analyzed the effect of diosgenin, administered with atorvastatin or ezetimibe, on the fate of ³H(G)-taurocholic acid or 26-14C-cholesterol in hypercholesterolemic rats. Male Wistar rats received a hypercholesterolemic diet (HD), HD + atorvastatin (HD+ATV), HD + ezetimibe (HD+EZT), HD + diosgenin (HD+DG), HD+ATV+EZT, or HD+ATV+DG for 40 days. We also included a control normal group (ND). The labelled compounds were administered on day 30. The animals were placed in metabolic cages for daily feces collection. At day 40 the rats were sacrificed. Lipid extracts from blood, liver, spinal cord, testicles, kidneys, epididymis, intestine, and feces were analyzed for radioactivity. Cholesterol activity was the highest in the liver in HD rats. DG diminished one half of this activity in HD+DG and HD+ATV+DG groups in comparison with the HD group. HD+ATV rats showed four to almost ten-fold cholesterol activity in the spinal cord compared with the ND or HD rats. Fecal elimination of neutral steroids was approximately two-fold higher in the HD+DG and HD+ATV+DG groups. Taurocholic acid activity was four to ten-fold higher in HD+DG intestine as compared to the other experimental groups. Taurocholic activity in the liver of HD and HD+DG groups was two and a half higher than in ND. Our results show that the combination of DG and ATV induced the highest cholesterol reduction in the liver and other tissues.
Asunto(s)
Anticolesterolemiantes/farmacología , Atorvastatina/farmacología , Ácidos y Sales Biliares/metabolismo , Colesterol/metabolismo , Diosgenina/farmacología , Ezetimiba/farmacología , Hipercolesterolemia/metabolismo , Animales , Anticolesterolemiantes/administración & dosificación , Atorvastatina/administración & dosificación , Diosgenina/administración & dosificación , Ezetimiba/administración & dosificación , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas WistarRESUMEN
Yam roots and other plants from Dioscorea genus have cultural, nutritional and economic importance to tropical and subtropical regions and have a great amount of diosgenin in its composition. In the present study the cytotoxic, genotoxic and mutagenic potential of diosgenin on HepG2 cells was investigated. Cytotoxicity was assessed using MTT and clonogenic assay. Genotoxic and mutagenic effects were performed using single cell gel electrophoresis and cytokinesis-block micronucleus assay, respectively. A reduction on cell viability was observed due to diosgenin treatment at concentrations higher than 30⯵M. A genotoxic effect was shown by comet assay and CBMN. Besides, an increase in micronucleus frequency along with a significant cytostatic effect were observed. Diosgenin elicited DNA damage on HepG2 cells which could not be efficiently repaired contributing to the mutagenic effect observed. Those results suggest that diosgenin deleterious effect could take place through genetic instability, fact that affects the normal cell cycle, leading to cell's death.
Asunto(s)
Diosgenina/toxicidad , Mutágenos/toxicidad , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Dioscorea/química , Células Hep G2 , Humanos , Pruebas de Micronúcleos , Sales de Tetrazolio/química , Tiazoles/químicaRESUMEN
In this paper is described a synthetic route to 6ß-phenylamino-cholestan-3ß,5α-diol and (25R)-6ß-phenylaminospirostan-3ß,5α-diol, starting from cholesterol and diosgenin, respectively. The products were obtained in two steps by epoxidation followed by aminolysis, through an environmentally friendly and solvent-free method mediated by SZ (sulfated zirconia) as catalyst. The use of SZ allows chemo- and regioselective ring opening of the 5,6α-epoxide during the aminolysis reaction eliminating the required separation of the epoxide mixture. The products obtained were spectroscopically characterized by 1H, PENDANT 13C NMR and HETCOR experiments, and complemented with FTIR-ATR and HRMS. The antiproliferative effect of the ß-aminoalcohols was evaluated on MCF-7 cells after 48h of incubation, by MTT and CVS assays. These methodologies showed that both compounds have antiproliferative activity, being more active the cholesterol analogue. Additionally, the cell images obtained by Harris' Hematoxylin and Eosin (H&E) staining protocol, evidenced formation of apoptotic bodies due to the presence of the obtained ß-aminoalcohols in a dose-dependent manner.
Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Colestanoles/síntesis química , Colestanoles/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Técnicas de Química Sintética , Colestanoles/química , Humanos , Células MCF-7RESUMEN
The stereoselective preparation of diosgenin-derived thio(seleno)ureas and glycomimetics bearing a 1,2,3-triazolyl tether on C-3 has been accomplished. The key steps in the synthetic pathway are the incorporation of an amino moiety and its further transformation into thio- and selenoureas, and also a click chemistry reaction involving a propargyl residue and an azido moiety to afford carbohydrate-derived 1,2,3-triazoles; subsequent BF3-promoted acetolysis of the spiranic moiety afforded the corresponding 22-oxocholestanic structure. The N-phenyl selenourea, an hitherto unknown steroidal derivative, turned out to be a potent ROS scavenger, in particular against free radicals (EC50 = 29.47 ± 2.33 µM, DPPH method), and as a glutathione peroxidase mimic in the elimination of H2O2 (t1/2 = 4.8 min, 1% molar ratio). 22-Oxocholestane structures bearing a C-3 azido, propargyl, thioureido, and particularly selenoureido moiety behaved as strong antiproliferative agents against HeLa cells (IC50 1.87-11.80 µM). N-phenyl selenourea also exhibited IC50 values lower than 6.50 µM for MDA-MB-231, MCF-7 and HepG2 cancer cells; apoptosis was found to be involved in its mode of action. Such compound was also capable of efficiently eliminating ROS endogenously produced by HeLa cells. Antiproliferative properties of thioxo and selenoxo derivatives were stronger than diosgenin.
Asunto(s)
Diosgenina/química , Diosgenina/farmacología , Diseño de Fármacos , Glicoconjugados/química , Glicoconjugados/farmacología , Compuestos de Organoselenio/química , Triazoles/química , Urea/análogos & derivados , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Materiales Biomiméticos/farmacología , Compuestos de Bifenilo/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diosgenina/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Glutatión Peroxidasa/metabolismo , Glicoconjugados/metabolismo , Humanos , Ratones , Picratos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Urea/químicaRESUMEN
The regioselective opening of the F ring of 22-oxo-23-spiroketals using BF3·OEt2 in acetic anhydride yielded novel cholestanic frameworks with pyranone E ring 20-23. The structures of the new derivatives of botogenin, diosgenin, hecogenin and tigogenin thus obtained were established using one and two dimensional (1)H, (13)C experiments (DEPT, COSY, HETCOR, HMBC). The X-ray diffraction analysis unequivocally confirmed the R configuration at C-23 in the starting 22-oxo-23-spiroketal 18 and the Z configuration of the C23-C24 double bond in the reaction product 20.
Asunto(s)
Boranos/química , Éter/química , Furanos/química , Compuestos de Espiro/química , Catálisis , Cristalografía por Rayos X , Conformación Molecular , EstereoisomerismoRESUMEN
Tubérculos del género Dioscorea comercializados con fines medicinales, fueron recolectados con el propósito de lograr su establecimiento a condiciones in vitro. Previamente se lograron identificar taxonómicamente las especies y por medio de análisis fitoquímicos demostrar su potencial farmacéutico. El material recolectado fue identificado como Dioscorea coriacea, D. lehmannii, D. meridensis, D. polygonoides y una especie comestible D. trifida. Tubérculos recolectados de centros de acopio y traídos de campo fueron lavados, desinfectados, asperjados con Ácido Giberélico (AG3) y sembrados en sustrato BM-2®, en invernadero a 18°C día y 10°C noche. Los tubérculos completos o por secciones fueron almacenados en bolsas herméticas a temperatura ambiente. Posteriormente se desinfectó material vegetal de las especies D. coriacea, D. lehmannii, D. meridensis y D polygonoides, seleccionando explantes de brotes sanos (D. coriacea / laboratorio) para su establecimiento. Se evaluaron tres medios de cultivo para establecimiento, el que presentó los mejores resultados fue Medio Murashige & Skoog (1962) suplementado con BAP 1 mL/L, AG3 1 mL/L y Putrescina 2 mL/L. Para la extracción y análisis de metabolitos secundarios se utilizaron tubérculos de D. coriacea, D. lehmannii y D. polygonoides, empleando como solvente de extracción metanol. Se encontró mayor concentración de extracto vegetal en D. coriacea (54%), y mediante cromatografía en capa delgada (CCD), se confirmó la presencia de saponinas, que resultó mayor en comparación con D. polygonoides especie reconocida por su alto contenido de saponinas. Estos resultados permitirán realizar análisis más avanzados de los compuestos presentes y plantear su propagación masiva en condiciones in vitro.
Wild tubers of the genus Dioscorea sold for medicinal use were collected for the purpose of achieving its establishment under in vitro conditions. First we taxonomically identified the species and through phytochemical analysis demonstrated pharmaceutical potential. The material collected was identified as Dioscorea coriacea, D. lehmannii, D. meridensis, D. polygonoides and the edible species D. trifida. Tubers collected from wholesale distributors and from the field were washed, disinfected, sprayed with Gibberellic Acid (GA3) and planted in substrate BM-2®, in a greenhouse at 18 ° C during the day and 10 ° C overnight. Whole tubers or sections thereof were stored in sealed bags at room temperature. Subsequently plant material of the species D. coriacea, D. lehmannii, D. meridensis and D. polygonoides was disinfected and healthy buds (D. coriacea / laboratory) were selected for in vitro establishment. Three different culture media were evaluated for establishment; that which presented the best results was the Murashige & Skoog (1962) medium, supplemented with BAP 1 mL / L, GA3 1 mL / L and Putrescin 2 mL / L. For the collection and analysis of secondary metabolites, tubers of D. coriacea, D. lehmannii and D. polygonoides were used, using methanol as the extraction solvent. The highest concentration of plant extract, 54%, was found in D. coriacea, a higher value than that of D. polygonoides, which had been reported previously; the presence of saponins was confirmed by thin layer chromatography (TLC). These results will enable more advanced analysis of the present compounds and enhance their mass propagation under in vitro conditions.
RESUMEN
This report presents evidence that the following Solanum steroids: solasodine, diosgenin and solanine interact with human erythrocytes and molecular models of their membranes as follows: a) X-ray diffraction studies showed that the compounds at low molar ratios (0.1-10.0mol%) induced increasing structural perturbation to dimyristoylphosphatidylcholine bilayers and to a considerable lower extent to those of dimyristoylphosphatidylethanolamine; b) differential scanning calorimetry data showed that the compounds were able to alter the cooperativity of dimyristoylphosphatidylcholine, dimyristoylphosphatidylethanolamine and dimyristoylphosphatidylserine phase transitions in a concentration-dependent manner; c) in the presence of steroids, the fluorescence of Merocyanine 540 incorporated to the membranes decreased suggesting a fluidization of the lipid system; d) scanning electron microscopy observations showed that all steroids altered the normal shape of human erythrocytes inducing mainly echinocytosis, characterized by the formation of blebs in their surfaces, an indication that their molecules are located into the outer monolayer of the erythrocyte membrane.
Asunto(s)
Diosgenina/química , Membrana Eritrocítica/química , Membrana Dobles de Lípidos/química , Alcaloides Solanáceos/química , Solanina/química , Rastreo Diferencial de Calorimetría , Dimiristoilfosfatidilcolina/química , Diosgenina/farmacología , Membrana Eritrocítica/efectos de los fármacos , Colorantes Fluorescentes/química , Humanos , Microscopía Electrónica de Rastreo , Transición de Fase/efectos de los fármacos , Fosfatidiletanolaminas/química , Fosfatidilserinas/química , Pirimidinonas/química , Dispersión del Ángulo Pequeño , Alcaloides Solanáceos/farmacología , Solanina/farmacología , Difracción de Rayos XRESUMEN
Background: The perennial medicinal herb Dioscorea zingiberensis is a very important plant used for steroid drug manufacturing for its high level of diosgenin in rhizome. Although the stimulation of diosgenin accumulation by ethylene has been reported in a few of plant species, its regulation is not yet characterized at the molecular level, the underlying molecular mechanism remains elusive. Results: In this study, the effects of ethylene on diosgenin biosynthesis in in vitro cultures of D. zingiberensis were described. The results showed that, in samples treated with ethylene at concentration E3 (10(4) dilution of 40% ethephon), the diosgenin biosynthesis was significantly promoted in comparison with the control samples. Treatment with high concentrations of ethylene had inhibitory effect, whereas with low concentration of the gas elicitor brought about no detectable deleterious effect on the growth rate and diosgenin content of the cultures. The considerable increase of diosgenin level in in vitro cultured Dioscorea zingiberensis by ethylene application is accompanied by the concomitant increase of soluble proteins and chlorophyll content. The gene expressions of cycloartenol synthase and 3-hydroxy-3-methylglutaryl-CoA reductase but not of squalene synthase or farnesyl pyrophosphate synthase were up-regulated by applied ethylene. Conclusions: Our results suggest that ethylene treatment enhanced diosgenin accumulation via up-regulation of the gene expressions of cycloartenol synthase and 3-hydroxy-3-methylglutaryl-CoA reductase.
Asunto(s)
Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Dioscorea/metabolismo , Hidroximetilglutaril-CoA Reductasas/genética , Hidroximetilglutaril-CoA Reductasas/metabolismo , Técnicas In Vitro , ARN/aislamiento & purificación , Expresión Génica , Regulación hacia Arriba , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Dioscorea/crecimiento & desarrollo , Dioscorea/genética , Diosgenina/análisis , EtilenosRESUMEN
Dioscorea multiflora uma planta nativa do Sul do Brasil produz a diosgenina como metabólito secundário majoritário, uma substância potencialmente usada pela indústria farmacêutica para a produção de cortisona e substâncias com ação contraceptiva. Objetivou-se, neste trabalho otimizar o protocolo de micropropagação de D. multiflora, visando a produção de mudas em escala comercial. Segmentos nodais subcultivados em meio MS sólido foram transferidos para multiplicação em meio MS suplementado com BAP (0,01; 0,1; 0,5; 1,0 e 3,0 mg L-1)e meio MS suplementado com 0,1 mg L-1 ou 0,5 mg L-1 de BAP acrescido de diferentes concentrações de sacarose (2, 4, 6, 8 e 10 por cento). Para o enraizamento, as brotações foram cultivadas em meio MS suplementado com AIB (0,1; 0,5; 1,0 e 3,0 mg L-1) e meio MS suplementado com ANA (0,1; 0,5; 1,0 e 3,0 mg L-1). Os experimentos in vitro foram instalados em delineamento experimental inteiramente casualizado e cada tratamento constituiu-se de 3 repetições e 10 cubetas/parcela. Plântulas com e sem raízes foram aclimatizadas em casa de vegetação. Melhores resultados de multiplicação e enraizamento foram obtidos em meio MS + 0,1 mg L-1 de BAP (80 por cento) e em meio MS + 1,0 mg L-1 de AIB (42,6 por cento), respectivamente. Não houve diferença quanto à porcentagem de sobrevivência das plântulas in vitro e ex vitro durante a aclimatização (75 por cento). O protocolo de micropropagação para D. Multiflora é efetivo e pode ser usado para a produção em escala comercial.
Dioscorea multiflora is a plant native to southern Brazil that produces diosgenin as a major secondary metabolite, a substance which is used by the pharmaceutical industry for the production of cortisone and substances with contraceptive action. The objective of this work was to optimize the micropropagation protocol of D. multiflora, for the production of seedlings on a commercial scale. Nodal segments subcultured in solid MS medium were transferred for multiplication to MS medium supplemented with BAP (0.01, 0.1, 0.5, 1.0 and 3.0 mg L-1) and MS medium supplemented with 0.1 mg L-1 or 0.5 mg L-1 BAP plus different concentrations of sucrose (2, 4, 6, 8 and 10 percent). For rooting, the shoots were cultured on MS medium supplemented with IBA (0.1, 0.5, 1.0 and 3.0 mg L-1) and MS medium supplemented with NAA (0.1, 0.5, 1.0 and 3.0 mg L-1). A completely randomized design was used with treatment consisting of 3 replicates with 10 buckets per plot. Seedlings with and without roots were acclimatized in a greenhouse. The best results of multiplication and rooting were obtained in MS medium + 0.1 mg L-1 BAP (80 percent) and in MS medium + 1.0 mg L-1 IBA (42.6 percent), respectively. There was no difference in the survival percentage of seedlings in vitro and during ex vitro acclimatization (75 percent). The micropropagation protocol for production of D. multiflora is effective and can be used for commercial production.