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1.
Curr Neuropharmacol ; 20(10): 1925-1940, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34517803

RESUMEN

Epilepsy is a devastating neurological disorder. Current anti-convulsant drugs are only effective in about 70% of patients, while the rest remain drug-resistant. Thus, alternative methods have been explored to control seizures in these drug-resistant patients. One such method may be through the utilization of fruit phytochemicals. These phytochemicals have been reported to have beneficial properties such as anti-convulsant, anti-oxidant, and anti-inflammatory activities. However, some fruits may also elicit harmful effects. This review aims to summarize and elucidate the anti- or pro-convulsant effects of fruits used in relation to seizures in hopes of providing a good therapeutic reference to epileptic patients and their carers. Three databases, SCOPUS, ScienceDirect, and PubMed, were utilized for the literature search. Based on the PRISMA guidelines, a total of 40 articles were selected for critical appraisal in this review. Overall, the extracts and phytochemicals of fruits managed to effectively reduce seizure activities in various preclinical seizure models, acting mainly through the activation of the inhibitory neurotransmission and blocking the excitatory neurotransmission. Only star fruit has been identified as a pro-convulsant fruit due to its caramboxin and oxalate compounds. Future studies should focus more on utilizing these fruits as possible treatment strategies for epilepsy.


Asunto(s)
Convulsivantes , Epilepsia , Convulsivantes/efectos adversos , Convulsivantes/análisis , Epilepsia/tratamiento farmacológico , Frutas/química , Humanos , Fitoquímicos/análisis , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico
2.
Chemosphere ; 214: 480-490, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30278402

RESUMEN

REACH requires information on hazardous properties of substances to be generated avoiding animal testing where possible. It is the objective of the present case study with thiochemicals to extract as much information as possible from available experimental data with fish, daphnia and algae and to fill data gaps for analogues to be registered under REACH in 2018. Based on considerations of chemical similarity and common mode of action (MOA) the data gaps regarding the aquatic toxicity of the thiochemicals were largely closed by trend analysis ("category approach") and read-across within the same group, for example, thioglycolates or mercaptopropionates. Among 16 thiochemicals to be registered by 2018 there are only 2 substances with sufficient data. 36 data gaps for 14 thiochemicals were identified. Most of the required data (>60%) could be estimated by in silico methods. Only 14 tests (6 algae, 6 daphnia, 1 limit fish test and 1 acute fish test) were proposed. When the results of these tests are available it has to be discussed whether 2 further fish (limit) tests are required. For two substances (exposure-based) waiving was suggested. The relatively high toxicity of the thiochemicals is manifested in low predicted no-effect concentrations (PNECs). Only preliminary predicted environmental concentrations (PECs) could be derived for the thiochemicals for which a risk assessment has to be performed (production rate >10 t/y). The preliminary PEC/PNEC ratios indicate no risk for the aquatic compartment at the production site. PECs due to down-stream use must not exceed the estimated PNECs.


Asunto(s)
Ácido 3-Mercaptopropiónico/toxicidad , Organismos Acuáticos/efectos de los fármacos , Minería de Datos , Técnicas de Apoyo para la Decisión , Exposición a Riesgos Ambientales/efectos adversos , Tioglicolatos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Ácido 3-Mercaptopropiónico/análisis , Animales , Convulsivantes/análisis , Convulsivantes/toxicidad , Daphnia/efectos de los fármacos , Monitoreo del Ambiente/métodos , Europa (Continente) , Peces/fisiología , Regulación Gubernamental , Medición de Riesgo , Tioglicolatos/análisis , Contaminantes Químicos del Agua/análisis
3.
Zhongguo Zhong Yao Za Zhi ; 37(6): 853-7, 2012 Mar.
Artículo en Chino | MEDLINE | ID: mdl-22715737

RESUMEN

OBJECTIVE: A sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method has been developed and validated for the determination of brucine and strychnine in rat plasma. METHOD: Samples were extracted by ethyl acetate-n-butanol (7: 3). Chromatographic separation was operated on ZORBAX XDB-C18 column with gradient elution of acetonitrile-methanol-water (0.05% acetic acid and 10 nmol x L(-1) ammonium formate contained), followed by LC-MS/MS in positive electrospray ionization. Quantification was carried out on multiple reaction monitoring (MRM) of the transition m/z 395.2/324.2, m/z 335.2/184.2 and m/z 199.1/171.1 for brucine, strychnine and tacrine (internal standard), respectively. RESULT: The method was linear in the range of 0.195-100 and 0.07840 microg x L(-1) for brucine and strychnine, with coefficient correlation 0.994 and 0.996 respectively. The recoveries of extraction were 78.9% - 102.4% for brucine and 95.2% - 106.1% for strychnine. Precision, accuracy, stability and matrix effect of the analytes met the requirement. The method was applied to a pharmacokinetic study of brucine and strychnine after cutaneous administration of Semen Strychni niosome gel. The C(max) were (26.20 +/- 5.81) and (12.50 +/- 3.00) microg x L(-1) while the AUC(0-infinity), were (193.75 +/- 39.43) and (98.25 +/- 28.54) microg x h x L(-1) of the two components. CONCLUSION: We conclude that the niosomes may reduce the systemic exposures and prolong the local release of brucine and strychnine.


Asunto(s)
Analgésicos/farmacocinética , Convulsivantes/farmacocinética , Plantas Medicinales/química , Estricnina/análogos & derivados , Estricnina/farmacocinética , Strychnos nux-vomica/química , Administración Cutánea , Analgésicos/análisis , Animales , Cromatografía Liquida , Convulsivantes/análisis , Femenino , Geles/química , Liposomas/química , Masculino , Ratas , Ratas Sprague-Dawley , Semillas/química , Organismos Libres de Patógenos Específicos , Estricnina/análisis , Espectrometría de Masas en Tándem
4.
Anal Bioanal Chem ; 396(3): 1213-21, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19943158

RESUMEN

The enzyme diisopropyl fluorophosphatase (DFPase, EC 3.1.8.2) from the squid Loligo vulgaris effectively catalyzes the hydrolysis of diisopropyl fluorophosphate (DFP) and a number of organophosphorus nerve agents, including sarin, soman, cyclosarin, and tabun. Until now, determination of kinetic data has been achieved by use of techniques such as pH-stat titration, ion-selective electrodes, and a recently introduced method based on in situ Fourier-transform infrared (FTIR) spectroscopy. We report the use of 1D (1)H-(31)P HSQC NMR spectroscopy as a new method for real-time quantification of the hydrolysis of toxic organophosphonates by DFPase. The method is demonstrated for the agents sarin (GB), soman (GD), and cyclosarin (GD) but can also be used for V-type nerve agents, for example VX. Besides buffered aqueous solutions the method was used to determine enzymatic activities in a biodiesel-based bicontinuous microemulsion that serves as an example of complex decontamination media, for which other established techniques often fail. The method is non-invasive and requires only limited manual handling of small volumes of liquid (700 microL), which adds to work safety when handling highly toxic organophosphorus compounds. Limits of detection are slightly below 100 micromol L(-1) on a 400 MHz spectrometer with 16 FIDs added for a single time frame. The method is not restricted to DFPase but can be used with other phosphotriesterases, for example paraxonase (PON), and even reactive chemicals, for example oximes and other nucleophiles, as long as the reaction components are compatible with the NMR experiment.


Asunto(s)
Técnicas Biosensibles/métodos , Sustancias para la Guerra Química/análisis , Inhibidores de la Colinesterasa/análisis , Espectroscopía de Resonancia Magnética/métodos , Compuestos Organofosforados/análisis , Hidrolasas de Triéster Fosfórico/metabolismo , Animales , Sustancias para la Guerra Química/metabolismo , Inhibidores de la Colinesterasa/metabolismo , Convulsivantes/análisis , Convulsivantes/metabolismo , Hidrólisis , Límite de Detección , Loligo/enzimología , Compuestos Organofosforados/metabolismo , Sarín/análisis , Sarín/metabolismo , Soman/análisis , Soman/metabolismo
5.
Toxicon ; 49(8): 1109-19, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-17395230

RESUMEN

This study was designed to document convulsant and neurotoxic properties of extracts of a tropical tree, Magnistipula butayei subsp. Montana, and to investigate the involvement of the glutamatergic system in these effects. Continuous behavioral observations and electroencephalographic (EEG) records were obtained after per os administration of an aqueous extract of Magnistipula (MBMAE) in rats. MBMAE (800 mg/kg) induced behavioral changes resembling motor limbic seizures: staring and head tremor, automatisms, forelimb clonic movements and violent tonic-clonic seizures leading to death in all animals. Concomitantly, important seizure activity that gradually evolved to epileptiform activity was recorded on the EEG. Moreover, c-Fos immunohistochemistry has revealed an increased c-Fos expression in the dentate gyrus and in piriform, peri- and entorhinal cortices 2 and 4h after treatment. This expression pattern suggested that the mechanism of action for the MBMAE is similar to that observed in glutamate-induced models of epilepsy. The MBMAE increased cell death also in hippocampal cell cultures. Furthermore, the build-up of convulsive activity and epileptic discharges induced by MBMAE in rat were abolished by MK-801, an NMDA receptor antagonist. Our study suggests that MBMAE contains a potent toxin, with a powerful neurotoxic activity in rat, and corresponding to a new natural component(s) that act as an NMDA-mediated convulsant molecule.


Asunto(s)
Chrysobalanaceae/química , Convulsivantes/toxicidad , Epilepsia Tónico-Clónica/inducido químicamente , Neurotoxinas/toxicidad , Extractos Vegetales/toxicidad , Análisis de Varianza , Animales , Convulsivantes/análisis , Maleato de Dizocilpina/farmacología , Electroencefalografía/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Inmunohistoquímica , Masculino , Neurotoxinas/análisis , Extractos Vegetales/análisis , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores
6.
Electrophoresis ; 19(16-17): 3003-7, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9870403

RESUMEN

The identification and quantitation of atropine, in whole blood and gastric contents in the presence of strychnine and tetracaine is described. This method uses liquid-liquid extraction and micellar electrokinetic chromatography (MECC). Separations are made using a 50 cm long capillary and a borate/phosphate buffer at pH 9.2 with 50 mM sodium dodecyl sulfate (SDS). Linearity was established for the three compounds between 1.0 and 100 microg/mL, using scopolamine as internal standard. The limit of detection for atropine was estimated at 0.06 microg/mL and the limit of quantitation at 0.2 microg/mL. The run time is less than 30 min. Alternate parameters are proposed to reduce the run time to under 10 min. The method was applied to a forensic post-mortem case.


Asunto(s)
Anestésicos Locales/análisis , Atropina/análisis , Convulsivantes/análisis , Contenido Digestivo/química , Midriáticos/análisis , Estricnina/análisis , Tetracaína/análisis , Anestésicos Locales/sangre , Atropina/sangre , Cromatografía Capilar Electrocinética Micelar , Convulsivantes/sangre , Humanos , Midriáticos/sangre , Estricnina/sangre , Tetracaína/sangre
7.
Pharmacol Biochem Behav ; 56(4): 595-601, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9130283

RESUMEN

Epileptogenesis during ontogeny may not be linearly related to time. It is known that the behavioral manifestations of seizures are age-dependent, but more research is needed to clarify ontogenetic aspects of epilepsies and related alterations, including cognitive deficits. Kindling is an accepted animal model for the study of the convulsive component of epilepsy and its consequences on behavior. Recently, we demonstrated an impairment in acquisition of a conditioned reaction in young adult kindled rats, using pentylenetetrazol (PTZ) as the kindling stimulus. The present study was undertaken to investigate the dependence on age of alterations in the induction of PTZ kindling in rats. We started the kindling protocol in 4-, 6-, and 8-week- and 6-, 12-, 18-, and 24-month-old rats. The PTZ kindling showed an age-dependent decrease in expression of convulsions. The diminished kindling capacity was already seen in 6-month-old rats. In contrast, kindling-related impairment effects on cognitive functions increased with age. Thus, the correlation between learning impairment and occurrence of tonic-clonic seizures that we had demonstrated in 8-week-old rats was abolished in older rats. On the other hand, when the kindling procedure was started in 6-week-old rats, no impairment was found in fully kindled rats.


Asunto(s)
Envejecimiento/fisiología , Reacción de Prevención/fisiología , Convulsivantes/toxicidad , Excitación Neurológica/fisiología , Pentilenotetrazol/toxicidad , Animales , Reacción de Prevención/efectos de los fármacos , Química Encefálica , Convulsivantes/análisis , Excitación Neurológica/efectos de los fármacos , Masculino , Pentilenotetrazol/análisis , Ratas , Ratas Wistar
8.
Endocrinology ; 130(3): 1211-6, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1537286

RESUMEN

L-T3 (T3) accumulates into cells in a temperature-dependent saturable manner through a purported iodothyronine membrane carrier protein. We report energy-dependent uptake of picomolar [125I]T3 into differentiated cell lines derived from human liver, human neuroblast, and rat pituitary malignancies. Furthermore, this cellular uptake is inhibited by classical and nonclassical benzodiazepine-type drugs (BZs); the apparent half-maximal inhibitory concentrations range from 50 nM to 50 microM, varying with drug and cell type. The site of this T3-BZ interaction was explored with cross-competitive radioligand binding to rat liver cell fractions. No interaction was seen in experiments cross-competing unlabeled T3 (10(-9)-10(-5) M) against [3H]Ro5 4864, a peripheral BZ receptor ligand, for binding sites in a crude rat liver mitochondrial fraction. As well, lormetazepam and triazolam, BZs that potently inhibit cellular uptake of [125I]T3, have no effect on [125I]T3 binding to rat liver nuclear sites. Studies of [3H]diazepam and [3H]Ro5 4864 show very little temperature-dependent uptake into HepG2 cells (less than 0.5% over 90 min) and no effect from coincubation of unlabeled T3 (1 microM). Thus, the possibility that BZs are substrates for the T3 carrier protein and are causing the reduced cellular hormonal accumulation via competitive uptake and dilution of the radiolabeled cellular T3 is unlikely. In summary, 1) drugs from the BZ class inhibit high affinity temperature-dependent cellular accumulation of thyroid hormone into cell lines from rat and human species; 2) the site of action of BZ inhibition does not involve direct antagonism of the T3 nuclear receptor, nor is it likely that the peripheral BZ receptor is the iodothyronine carrier. BZs could be interacting with the purported iodothyronine carrier protein itself to block uptake.


Asunto(s)
Adenoma/metabolismo , Adenoma/patología , Ansiolíticos , Benzodiazepinas/farmacología , Hígado/citología , Hígado/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patología , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Temperatura , Triyodotironina/metabolismo , Adenoma/química , Animales , Benzodiazepinonas/análisis , Benzodiazepinonas/metabolismo , Línea Celular , Convulsivantes/análisis , Convulsivantes/metabolismo , Diazepam/análisis , Diazepam/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Radioisótopos de Yodo , Hígado/química , Lorazepam/análogos & derivados , Lorazepam/farmacología , Neuroblastoma/química , Neoplasias Hipofisarias/química , Ratas , Receptores de Hormona Tiroidea/efectos de los fármacos , Triazolam/farmacología , Tritio , Células Tumorales Cultivadas/química , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/patología
9.
Neurosci Lett ; 122(2): 265-9, 1991 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-1827518

RESUMEN

Many of the characteristics neuroanatomical and neurochemical features of Huntington's disease (HD) are produced in experimental animals by an intrastriatal injection of the endogenous N-methyl-D-aspartate receptor agonist quinolinic acid (QUIN). Conceivably, a chronic over-production of QUIN in brain could be involved in the pathogenesis of HD. To investigate this hypothesis, concentrations of QUIN were measured both in cerebrospinal fluid (CSF) and postmortem tissue from patients with HD and neurologically normal age-matched controls. CSF QUIN concentrations were slightly lower in patients with HD, however the changes were not significant. Mean concentrations of QUIN tended to be lower in HD putamen, dentate nucleus and several cortical regions, although significant reductions were found only in Brodmann areas 17, 20 and 28. The mechanisms responsible for these small reductions in brain QUIN concentrations remain to be determined. These results do not support the hypothesis that a chronic increase of QUIN production is responsible for neurodengeneration in HD.


Asunto(s)
Química Encefálica , Enfermedad de Huntington/metabolismo , Ácidos Quinolínicos/análisis , Adulto , Convulsivantes/análisis , Femenino , Humanos , Enfermedad de Huntington/líquido cefalorraquídeo , Masculino , Persona de Mediana Edad , Especificidad de Órganos , Ácido Quinolínico , Ácidos Quinolínicos/líquido cefalorraquídeo , Valores de Referencia
10.
Chem Pharm Bull (Tokyo) ; 38(1): 291-2, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2337950

RESUMEN

A new toxic neoanisatin-derivative (1) was isolated from the pericarps of Illicium majus. The structure of this compound was elucidated by spectroscopic data, including the 2D COSY NMR technique. The toxicity of compound 1 is also described.


Asunto(s)
Lactonas , Plantas Tóxicas/análisis , Sesquiterpenos/análisis , Animales , Convulsivantes/análisis , Japón , Ratones , Ratones Endogámicos , Sesquiterpenos/toxicidad
11.
Arch Invest Med (Mex) ; 21(1): 35-44, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1699504

RESUMEN

A qualitative X-ray spectrometric study oriented to demonstrate ruthenium (Ru) in central nervous system was made after intraperitoneal (i.p.) injection of ruthenium red (RuR) to adult rats. Ru signals were depicted in the brain synaptosomal fraction since 60 min after RuR i.p. administration, corresponding to the latency period of the convulsive model injecting RuR systemically to adult rats. Ru signals were initially detected in pineal gland and periventricular regions, whereas X-rays from Ru atoms in cerebral cortex were detected at longer time intervals after RuR i.p. injection. It is concluded that RuR, a non-liposoluble substance, when injected systemically, passes from the blood stream to brain parenchyma, probably through areas without blood-brain barrier, reaching the neural elements related to the mechanisms of production of convulsions.


Asunto(s)
Química Encefálica , Convulsivantes/farmacocinética , Microanálisis por Sonda Electrónica , Rojo de Rutenio/farmacocinética , Animales , Barrera Hematoencefálica , Bloqueadores de los Canales de Calcio/análisis , Bloqueadores de los Canales de Calcio/farmacocinética , Bloqueadores de los Canales de Calcio/toxicidad , Convulsivantes/análisis , Convulsivantes/toxicidad , Inyecciones Intraperitoneales , Glándula Pineal/química , Ratas , Ratas Endogámicas , Rojo de Rutenio/análisis , Rojo de Rutenio/toxicidad , Solubilidad , Sinaptosomas/química
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