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1.
J Ethnopharmacol ; 248: 112305, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31639490

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The development of selective inhibitors of monoamine oxidase B (MAO-B) has been essential in treating Parkinson's disease. However, the apparent hepatotoxicity and drug-drug interactions of current inhibitors accentuate the need for the development of novel pharmacotherapies. Crossyne guttata (L.) D. & U. Müll-Doblies is used frequently by Rastafarian bush doctors to treat alcoholism, a disorder which is also accentuated by MAO. OBJECTIVE: The study sought to isolate, identify and characterise the biologically active constituents of C. guttata based on their ability to inhibit the MAO enzymes. MATERIALS AND METHODS: Column chromatography was used to isolate the biologically active alkaloids of C. guttata. The ability of the alkaloids to inhibit the biotransformation of 4-aminoantipyrine by the MAO enzymes was evaluated in vitro. In silico docking was conducted using AutoDock Vina server while the pharmacokinetic properties of the compounds were evaluated using SwissADME. RESULTS: Chromatographic separation of an ethanolic fraction of C. guttata yielded the alkaloids crinamine 1 and epibuphanisine 2. 1 and 2 along with structurally related alkaloids haemanthamine 3 and haemanthidine 4 were evaluated for their ability to inhibit the action of isozymes of MAO in vitro. Alkaloids effected submicromolar IC50 values against MAO-B, the most potent of which being crinamine 1 (0.014 µM) > haemanthidine 4 (0.017 µM) > epibuphanisine 2 (0.039 µM) > haemanthamine 3 (0.112 µM). Binding energies of the alkaloids correlated well with their inhibitory potential with crinamine displaying the best binding efficacy and binding energy score with MAO-B. DISCUSSION AND CONCLUSION: Crinamine and epibuphanisine exhibited potent and selective inhibitory activity towards MAO-B. After comprehensive in silico investigations encompassing robust molecular docking analysis, the drug-like attributes and safety of the alkaloids suggest the crinamine is a potentially safe drug for human application.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Modelos Biológicos , Simulación del Acoplamiento Molecular , Inhibidores de la Monoaminooxidasa/farmacología , Monoaminooxidasa/metabolismo , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacocinética , Alcaloides de Amaryllidaceae/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Humanos , Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/química , Inhibidores de la Monoaminooxidasa/farmacocinética , Inhibidores de la Monoaminooxidasa/toxicidad , Mutación , Seguridad del Paciente , Conformación Proteica , Medición de Riesgo , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Relación Estructura-Actividad , Células Vero
2.
Biomed Res Int ; 2019: 1851740, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31275963

RESUMEN

The human opportunistic fungal pathogen Candida albicans causes a severe health burden while the biofilms formed by C. albicans present a kind of infections that are hard to cure, highlighting the pressing need for new antifungal drugs against C. albicans. This study was to explore the antifungal activities of lycorine hydrochloride (LH) against C. albicans. The minimal inhibitory concentration (MIC) of LH against C. albicans SC5314 was 64 µM. Below its MIC, LH demonstrated antivirulence property by suppressing adhesion, filamentation, biofilm formation, and development, as well as the production of extracellular phospholipase and exopolymeric substances (EPS). The cytotoxicity of LH against mammalian cells was low, with half maximal inhibitory concentrations (IC50) above 256 µM. Moreover, LH showed a synergistic effect with AmB, although its interaction with fluconazole, as well as caspofungin, was indifferent. Thus, our study reports the potential use of LH, alone or in combination with current antifungal drugs, to fight C. albicans infections.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Candida albicans/patogenicidad , Fenantridinas/farmacología , Adhesividad/efectos de los fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/toxicidad , Antifúngicos/química , Antifúngicos/farmacología , Antifúngicos/toxicidad , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida albicans/fisiología , Muerte Celular/efectos de los fármacos , AMP Cíclico/metabolismo , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Hifa/efectos de los fármacos , Fenantridinas/química , Fenantridinas/toxicidad , Fosfolipasas/metabolismo , Virulencia/efectos de los fármacos
3.
Phytomedicine ; 60: 152832, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31031043

RESUMEN

BACKGROUND: Successful cancer chemotherapy is hampered by resistance of cancer cells to established anticancer drugs. Numerous natural products reveal cytotoxicity towards tumor cells. PURPOSE: The present study was aimed to determine the cytotoxicity of a betaine-type alkaloid, ungeremine, towards 9 cancer cell lines including various sensitive and drug-resistant phenotypes. The mode of action of this compound was further investigated. METHODS: The cytotoxicity, ferroptotic and necroptotic cell death were determined by the resazurin reduction assay. Caspase activation was evaluated using the caspase-Glo assay. Flow cytometry was applied for the analysis of cell cycle analysis (PI staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP) (JC-1) and reactive oxygen species (ROS) (H2DCFH-DA). Apoptotic, necroptotic and autophagic markers were determined by Western blotting. CCRF-CEM leukemia cells were used for all mechanistic studies. RESULTS: Ungeremine displayed cytotoxic activity towards the 9 cancer cell lines tested, including drug-sensitive and MDR phenotypes. The IC50values obtained varied from 3.67 µM (in MDA-MB-231-BCRP breast carcinoma cells) to 75.24 µM (against in CEM/ADR5000 leukemia cells) for ungeremine and from 0.02 µM (against CCRF-CEM cells) to 122.96 µM (against CEM/ADR5000 cells) for doxorubicin (control drug). Ungeremine induced ferroptosis, necroptosis, autophagy as well as apoptosis mediated by caspase activation, MMP alteration and increase ROS production. CONCLUSION: The present investigation showed that ungeremine is a promising cytotoxic compoundthat could be further explored in the future to develop new anticancer drugs to fight sensitive and resistant phenotypes.


Asunto(s)
Alcaloides/toxicidad , Alcaloides de Amaryllidaceae/toxicidad , Antineoplásicos Fitogénicos/toxicidad , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Indolizinas/toxicidad , Extractos Vegetales/toxicidad , Alcaloides de Amaryllidaceae/química , Antineoplásicos Fitogénicos/química , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Indolizinas/química , Extractos Vegetales/química , Especies Reactivas de Oxígeno/metabolismo
4.
Food Chem Toxicol ; 125: 605-613, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30738987

RESUMEN

Lycoris radiata (L'Her.) Herb. (L. radiata) was traditionally used as a folk medicine in China for treatment of Alzheimer's disease. However, the specific component responsible for its considerable toxicity remained unclear thus restricting its clinical trials. Narciclasine (NCS) was isolated from L. radiata and treatment of NCS for 72 h exhibited significant antiproliferative effects against L02, Hep G2, HT-29 and RAW264.7 cells. However, what needs to be emphasized is that at safe working concentrations of 0.001-0.016 µM, administration of NCS for 24 h inhibited the mRNA expression of inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-ɑ), interleukin-1beta (IL-1ß) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-induced macrophages thereby suppressing production of nitric oxide (NO), IL-6, TNF-ɑ and IL-1ß. NCS supplementation also inhibited nuclear factor-kappa B (NF-κB) activation by suppressing NF-κB P65 phosphorylation and nuclear translocation, IκBɑ degradation and phosphorylation, and IκKɑ/ß phosphorylation. The phosphorylation of c-Jun N-terminal kinase (JNK) and P38, and expression of COX-2 was also attenuated by NCS. These results suggested that NCS might exert anti-inflammatory effects through inhibiting NF-κB and mitogen-activated protein kinase (MAPK) pathways even at very low doses.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Antiinflamatorios/farmacología , Lycoris/química , Macrófagos/efectos de los fármacos , Fenantridinas/farmacología , Alcaloides de Amaryllidaceae/aislamiento & purificación , Alcaloides de Amaryllidaceae/toxicidad , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/toxicidad , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Inflamación/inducido químicamente , Lipopolisacáridos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , FN-kappa B/metabolismo , Fenantridinas/aislamiento & purificación , Fenantridinas/toxicidad , Componentes Aéreos de las Plantas/química , Células RAW 264.7 , ARN Mensajero/genética , ARN Mensajero/metabolismo
5.
Nat Prod Commun ; 9(8): 1193-210, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25233606

RESUMEN

The plant family Amaryllidaceae is renowned for its unique alkaloid constituents which possess a significant array of structural diversity. Several of these alkaloids are known for their interesting biological properties, of which galanthamine and pancratistatin have acquired a privileged status due to their relevance in the pharmaceutical arena. In particular, galanthamine represents the first prescription drug emanating from the Amaryllidaceae after its approval by the FDA in 2001 for the treatment of Alzheimer's disease. Following on this commercial success there have been sustained projections for the emergence of an anticancer agent related to pancratistatin due to the potency, selectivity, low toxicity and high tolerability typifying targets of this series of alkaloids. The lycorine series of alkaloids have also garnered widespread interest as cytotoxic agents and were amongst the earliest of the Amaryllidaceae constituents to exhibit such activity. To date over 100 of such naturally-occurring or synthetically-derived alkaloids have been screened for cytotoxic effects against a number of cancer cell lines. This survey examines the cytotoxic properties of lycorine alkaloids, highlights the outcomes of structure-activity relationship orientated studies and affords plausible insights to the mechanistic rationale behind these effects.


Asunto(s)
Alcaloides de Amaryllidaceae/toxicidad , Liliaceae/efectos adversos , Fenantridinas/toxicidad , Extractos Vegetales/toxicidad , Alcaloides de Amaryllidaceae/química , Animales , Humanos , Liliaceae/química , Fenantridinas/química , Extractos Vegetales/química
6.
Protoplasma ; 251(5): 1113-24, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24482192

RESUMEN

Narciclasine (NCS) is an Amaryllidaceae alkaloid isolated from Narcissus tazetta bulbs. Its phytotoxic effects on plant growth were examined in lettuce (Lactuca sativa L.) seedlings. Results showed that high concentrations (0.5-5 µM) of NCS restricted the growth of lettuce roots in a dose-dependent manner. In NCS-treated lettuce seedlings, the following changes were detected: reduction of mitotic cells and cell elongation in the mature region, inhibition of proliferation of meristematic cells, and cell cycle. Moreover, comet assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay indicated that higher levels NCS (0.5-5 µM) induced DNA damage in root cells of lettuce. The decrease in meristematic cells and increase in DNA damage signals in lettuce roots in responses to NCS are in a dose-dependent manner. NCS-induced reactive oxygen species accumulation may explain an increase in DNA damage in lettuce roots. Thus, the restraint of root growth is due to cell cycle arrest which is caused by NCS-induced DNA damage. In addition, it was also found that NCS (0.5-5 µM) inhibited the root hair development of lettuce seedlings. Further investigations on the underlying mechanism revealed that both auxin and ethylene signaling pathways are involved in the response of root hairs to NCS.


Asunto(s)
Alcaloides de Amaryllidaceae/toxicidad , Puntos de Control del Ciclo Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Lactuca/efectos de los fármacos , Fenantridinas/toxicidad , Raíces de Plantas/crecimiento & desarrollo , Alcaloides de Amaryllidaceae/farmacología , Proliferación Celular/efectos de los fármacos , Etilenos/metabolismo , Etiquetado Corte-Fin in Situ , Ácidos Indolacéticos/metabolismo , Meristema/citología , Meristema/crecimiento & desarrollo , Índice Mitótico , Estrés Oxidativo/efectos de los fármacos , Fenantridinas/farmacología , Raíces de Plantas/citología , Especies Reactivas de Oxígeno/metabolismo , Plantones/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
7.
Molecules ; 18(3): 2458-68, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23439562

RESUMEN

Phytochemical investigation of the 80% ethanol extract of the bulbs of Lycoris radiata resulted in the isolation of five new Amaryllidaceae alkaloids: (+)-5,6-dehydrolycorine (1), (+)-3α,6ß-diacetyl-bulbispermine (2), (+)-3α-hydroxy-6ß-acetyl- bulbispermine (3), (+)-8,9-methylenedioxylhomolycorine-N-oxide (5), and 5,6-dihydro-5- methyl-2-hydroxyphenanthridine (7), together with two known compounds, (+)-3α-methoxy- 6ß-acetylbulbispermine (4) and (+)-homolycorine- N-oxide (6). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. Alkaloid 1 showed potent cytotoxicity against astrocytoma and glioma cell lines (CCF-STTG1, CHG-5, SHG-44, and U251), as well as HL-60, SMMC-7721, and W480 cell lines with IC(50) values of 9.4-11.6 µM. Additonally, compound 1 exhibited antimalarial activity with IC(50) values of 2.3 µM for D-6 strain and 1.9 µM for W-2 strain of Plasmodium falciparum.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Antimaláricos/farmacología , Lycoris/química , Raíces de Plantas/química , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/toxicidad , Antimaláricos/química , Antimaláricos/toxicidad , Línea Celular Tumoral , Células HL-60 , Humanos , Resonancia Magnética Nuclear Biomolecular , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plasmodium falciparum/efectos de los fármacos
8.
J Ethnopharmacol ; 143(2): 572-8, 2012 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-22835813

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Boophane disticha of the family Amaryllidaceae is used traditionally in southern Africa in the treatment of several neurological disorders. AIM OF THE STUDY: Although acetylcholinesterase (AChE) inhibitory activity has been reported for this plant, the aim of the study was to identify and characterise the compound responsible for this activity using bioassay guided fractionation. Toxicity of the isolated compound was also assessed. MATERIALS AND METHODS: Bioassay guided isolation of the active compound from the methanol extract was carried out using column chromatography, TLC and preparative thin layer chromatography. Structural elucidation was carried out using high field 1D and 2D NMR and mass spectroscopy. AChE inhibitory activity was determined using the Ellman's colorimetric method. Cytotoxicity assessment was determined in human neuroblastoma (SH-SY5Y) cells using the MTT and neutral red uptake assays. RESULTS: The data obtained from the integration of the (1)H spectra confirmed the compound to be a 3:1 mixture of two epimers, with epimer A, 6α-hydroxycrinamine as the major epimer. The IC(50) value for AChE inhibitory activity of the compound was 445 µM. The compound was observed to be cytotoxic in both the MTT and neutral red assays with IC(50) values of 54.5 and 61.7 µM, respectively. CONCLUSION: The present study describes for the first time, the isolation of 6-hydroxycrinamine, a crinine alkaloid, from the methanol extract of the bulbs of B. disticha. Although this compound possessed AChE inhibitory activity, it was found to be toxic to the neuroblastoma cells. Quantitative structure-activity relationship studies could be carried out to modify the structure in order to make it less toxic and improve its activity.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Inhibidores de la Colinesterasa/farmacología , Liliaceae , Extractos Vegetales/farmacología , Acetilcolinesterasa/metabolismo , Alcaloides de Amaryllidaceae/aislamiento & purificación , Alcaloides de Amaryllidaceae/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidores de la Colinesterasa/toxicidad , Humanos , Metanol/química , Extractos Vegetales/toxicidad , Solventes/química
9.
Arch Pharm Res ; 34(7): 1065-70, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21811912

RESUMEN

Phenanthridone alkaloids are envisaged as an attractive lead for the development of anticancer agents. We have prepared a series of aromatized analogues on the basis of the structure of this class of alkaloids with the hope of finding the simplified compounds with comparable activities. The obtained analogues were evaluated for their cytotoxic effect against several cancer cell lines and found to be virtually inactive. These observations together with molecular modeling studies strongly suggest that the stereochemistries of hydroxyl groups in C-ring of phenanthridone alkaloids are crucial to biological effects.


Asunto(s)
Alcaloides/síntesis química , Alcaloides/toxicidad , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Fenantrenos/química , Fenantrenos/farmacología , Alcaloides/química , Alcaloides/farmacología , Alcaloides de Amaryllidaceae/toxicidad , Antineoplásicos/química , Antineoplásicos/toxicidad , Línea Celular Tumoral , Diseño de Fármacos , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Fenómenos Electrofisiológicos , Humanos , Concentración 50 Inhibidora , Modelos Químicos , Fenantrenos/toxicidad , Estereoisomerismo , Relación Estructura-Actividad
10.
Arch Toxicol ; 85(12): 1565-73, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21626407

RESUMEN

Lycorine is the main alkaloid of many Amaryllidaceae and known to cause poisoning with still unknown mechanisms. Longer lasting toxicological core symptoms of nausea and emesis may become a burden for human and animal patients and may result in substantial loss of water and electrolytes. To optimise the only empirical symptomatic antiemetic drug treatment at present, it is important to elucidate the causative involved targets of lycorine-induced emesis. Therefore, in the current study, we have tested the actions of a various antiemetic drugs with selective receptor affinities on lycorine-induced nausea and emesis in vivo in dogs. Beagle dogs were pre-treated in a saline vehicle-controlled crossover and random design with diphenhydramine, maropitant, metoclopramide, ondansetron or scopolamine prior lycorine administration (2 mg/kg subcutaneously). In vivo effects were assessed by a scoring system for nausea and emesis as well as by the number and lag time of emetic events for at least 3 h. Moreover, plasma pharmacokinetic analysis was carried out for ondansetron before and after lycorine injection. The data show that histaminergic (H1), muscarinic and dopaminergic (D2) receptors are presumably not involved in lycorine-induced emetic effects. While ondansetron significantly reduced the number of emetic events, lycorine-induced emesis was completely blocked by maropitant. Only ondansetron also significantly decreased the level of nausea and was able to prolong the lag time until onset of emesis suggesting a preferential participation of 5-HT3 receptors in lycorine-induced nausea. Thus, it is the first in vivo report evidencing that predominantly neurokinin-1 (NK1) and to a lesser extent 5-hydroxytryptamine 3 (5-HT3) receptors are involved in lycorine-induced emesis facilitating a target-oriented therapy.


Asunto(s)
Alcaloides de Amaryllidaceae/toxicidad , Antieméticos/farmacología , Náusea/prevención & control , Fenantridinas/toxicidad , Vómitos/prevención & control , Animales , Antieméticos/farmacocinética , Estudios Cruzados , Perros , Sistemas de Liberación de Medicamentos , Femenino , Inyecciones Subcutáneas , Masculino , Náusea/inducido químicamente , Distribución Aleatoria , Receptores de Neuroquinina-1/efectos de los fármacos , Receptores de Neuroquinina-1/metabolismo , Receptores de Serotonina 5-HT3/efectos de los fármacos , Receptores de Serotonina 5-HT3/metabolismo , Factores de Tiempo , Vómitos/inducido químicamente
12.
Int J Oncol ; 38(6): 1549-56, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21424119

RESUMEN

The Amaryllidaceae alkaloid pancratistatin has been proven to selectively induce apoptotic cell death in a variety of human cancer cells with an insignificant effect on non-cancerous cells. In this study we report, for the first time, the effects of pancratistatin (PST) on models of metastatic prostate cancer. The effects of pancratistatin on prostate cancer DU145 and LNCaP cell lines was assessed by microscopy, enzymatic activity assays and Western blotting. Apoptosis was determined by nuclear condensation and caspase activation, and autophagy was observed by MDC staining and LC3 expression levels. Human prostate xenografts were used to test the potential therapeutic efficacy of intra-tumor administration of pancratistatin in vivo. Pancratistatin treatment reduced cell viability and induced apoptosis in androgen-responsive (LNCaP) and androgen-refractory (DU145) prostate cancer cell lines in a dose- and time-dependent manner, but with an insignificant effect on normal human fibroblast (NHF) cells at the effective dose. Increased reactive oxygen species production and collapse of mitochondrial membrane potential resulted from treatment with pancratistatin in both cancer cell lines. This study presents the novel finding that pancratistatin treatment caused decreased migration capacity and increased autophagy levels in metastatic prostate cancer cells. Importantly, in this proof-of-concept study, pancratistatin reduced the volume of xenograft tumors compared to control-treated animals, and was well-tolerated. Our results highlight the potential of pancratistatin for clinical development as a selective therapeutic for treatment of metastatic prostate cancer.


Asunto(s)
Alcaloides de Amaryllidaceae/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Isoquinolinas/farmacología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/uso terapéutico , Alcaloides de Amaryllidaceae/toxicidad , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Caspasas/metabolismo , Línea Celular , Movimiento Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Humanos , Isoquinolinas/química , Isoquinolinas/uso terapéutico , Isoquinolinas/toxicidad , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Neoplasias de la Próstata/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Toxicon ; 57(1): 117-24, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21055413

RESUMEN

Ingestions of plant material from Amaryllidaceae, especially the bulbs of daffodils, are known to be toxic, representing a persistent cause of poisoning in human and animals. Empiric data from case reports suggested, that the alkaloid lycorine could be the toxic constituent of the multi-component mixture responsible for symptoms like nausea and emesis. Systematic studies of the in vivo effects of the amaryllidaceaeous-type alkaloids are not available. Therefore, in an open, prospective, randomized and controlled trial we studied the dose-effect relationship of lycorine-induced nausea and emesis and the toxicokinetics of lycorine in beagle dogs. Subcutaneously administered lycorine-induced nausea and emesis starting at 0.5 mg/kg body weight reaching statistical significance at 1.0 mg/kg. The maximum emetic dose of lycorine (ED(100)) was 2 mg/kg body weight. There was a correlation between dose and nausea score as well as between dose and number of the induced emetic events. Nausea and emesis were short-lasting and occurred not later than 2.5 h post dose. Lycorine showed linear plasma kinetics with a mean elimination half-life of 0.67 and 0.3 h after single s.c. and i.v. administration, compatible with the clinical course of nausea and emesis. The mean oral bioavailability was calculated to be about 40%. Biochemical and haematological parameters of safety showed no pathological signs. The results provide evidence that lycorine can be considered as a main, if not the crucial constituent responsible for nausea and emesis in human and animals in poisoning due to ingestion of plant material of the Amaryllidaceae.


Asunto(s)
Alcaloides de Amaryllidaceae/toxicidad , Eméticos/toxicidad , Liliaceae/química , Náusea/inducido químicamente , Fenantridinas/toxicidad , Vómitos/inducido químicamente , Alcaloides de Amaryllidaceae/sangre , Alcaloides de Amaryllidaceae/farmacocinética , Animales , Área Bajo la Curva , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Pruebas de Química Clínica , Perros , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Eméticos/sangre , Eméticos/farmacocinética , Femenino , Semivida , Pruebas Hematológicas , Masculino , Fenantridinas/sangre , Fenantridinas/farmacocinética , Extractos Vegetales/sangre , Extractos Vegetales/farmacocinética , Extractos Vegetales/toxicidad , Estudios Prospectivos
14.
J Med Chem ; 52(20): 6244-56, 2009 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-19788245

RESUMEN

Twenty-two lycorine-related compounds were investigated for in vitro antitumor activity using four cancer cell lines displaying different levels of resistance to proapoptotic stimuli and two cancer cell lines sensitive to proapoptotic stimuli. Lycorine and six of its congeners exhibited potency in the single-digit micromolar range, while no compound appeared more active than lycorine. Lycorine also displayed the highest potential (in vitro) therapeutic ratio, being at least 15 times more active against cancer than normal cells. Our studies also showed that lycorine exerts its in vitro antitumor activity through cytostatic rather than cytotoxic effects. Furthermore, lycorine provided significant therapeutic benefit in mice bearing brain grafts of the B16F10 melanoma model at nontoxic doses. Thus, the results of the current study make lycorine an excellent lead for the generation of compounds able to combat cancers, which are naturally resistant to proapoptotic stimuli, such as glioblastoma, melanoma, non-small-cell-lung cancers, and metastatic cancers, among others.


Asunto(s)
Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Fenantridinas/química , Fenantridinas/farmacología , Actinas/metabolismo , Alcaloides de Amaryllidaceae/uso terapéutico , Alcaloides de Amaryllidaceae/toxicidad , Animales , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Femenino , Humanos , Concentración 50 Inhibidora , Dosis Máxima Tolerada , Melanoma/tratamiento farmacológico , Ratones , Fenantridinas/uso terapéutico , Fenantridinas/toxicidad , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Z Naturforsch C J Biosci ; 63(9-10): 639-43, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19040099

RESUMEN

In the context of the study on plant defensive compounds we have isolated the main alkaloid from Hippeastrum puniceum (Amaryllidaceae), 3-O-acetyl-narcissidine (1), and its biological activities tested against two divergent insect species and several plant species. 1 was isolated from the bioactive alkaloidal fraction of H. puniceum. Its chemical structure was established by spectroscopic analysis. The biological activity tests showed that 1 is an antifeedant against the polyphagous insect Spodoptera littoralis but not against the olyphage Leptinotarsa decemlineata. Furthermore, the root growth of Amaranthus hypochondriacus, Rottboellia cochinchinensis, Panicum maximum and Solanum lycopersicum was significantly affected by 1. These results suggest a plant protective role for H. puniceum alkaloids.


Asunto(s)
Alcaloides/química , Alcaloides de Amaryllidaceae/química , Compuestos Heterocíclicos de 4 o más Anillos/química , Compuestos Heterocíclicos de 4 o más Anillos/toxicidad , Insecticidas/química , Insecticidas/toxicidad , Liliaceae/química , Spodoptera/efectos de los fármacos , Aconitina/farmacología , Alcaloides/aislamiento & purificación , Amaranthus/efectos de los fármacos , Amaranthus/crecimiento & desarrollo , Alcaloides de Amaryllidaceae/aislamiento & purificación , Alcaloides de Amaryllidaceae/farmacología , Alcaloides de Amaryllidaceae/toxicidad , Animales , Compuestos Heterocíclicos de 4 o más Anillos/aislamiento & purificación , Insecticidas/aislamiento & purificación , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/crecimiento & desarrollo , Fisostigmina/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Plantas/efectos de los fármacos
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