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1.
Microb Pathog ; 103: 13-18, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27988226

RESUMEN

Aniba canelilla (H.B.K.) Mez, popularly known as "casca-preciosa" (precious bark), is a plant of the Lauraceae family, widely distributed in the Amazon region. Its major constituent is 1-nitro-2-phenylethane, a rare molecule in plants which is responsible for this plant's cinnamon scent. The present study aimed to report the chemical characterization of the oil extracted from Aniba canelilla using gas-chromatography/mass spectrometry and to assess its in vitro trypanocidal activity against Trypanosoma evansi, a prevalent haemoflagellate parasite that affects a broad range of mammal species in Africa, Asia and South America. The oil presented 1-nitro-2-phenylethane (83.68%) and methyleugenol (14.83%) as the two major components. The essential oil as well as both major compounds were shown to exert trypanocidal effect. Methyleugenol was slightly more active than 1-nitro-2-phenylethane. In vitro studies showed that the oil extracted from the stems of A. canelilla may be regarded as a potential natural treatment for trypanosomosis, once proven their in vivo action, may be an interesting alternative in the treatment of infected animals with T. evansi.


Asunto(s)
Embryophyta/química , Linfocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Tripanocidas/farmacología , Trypanosoma/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromatografía de Gases , Humanos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/química , Aceites de Plantas/química , Tripanocidas/química
2.
Drug Dev Ind Pharm ; 43(3): 511-518, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27915573

RESUMEN

Thalidomide (THD) is a BCS class II drug with renewed and growing therapeutic applicability. Along with the low aqueous solubility, additional poor biopharmaceutical properties of the drug, i.e. chemical instability, high crystallinity, and polymorphism, lead to a slow and variable oral absorption. In this view, we developed solid dispersions (SDs) containing THD dispersed in different self-emulsifying carriers aiming at an enhanced absorption profile for the drug. THD was dispersed in lauroyl macrogol-32 glycerides (Gelucire® 44/14) and α-tocopherol polyethylene glycol succinate (Kolliphor® TPGS), in the presence or absence of the precipitation inhibitor polyvinylpyrrolidone K30 (PVP K30), by means of the solvent method. Physicochemical analysis revealed the formation of semicrystalline SDs. X-ray diffraction and infrared spectroscopy analyses suggest that the remaining crystalline fraction of the drug in the SDs did not undergo polymorphic transition. The impact of the solubility-enhancing formulations on the THD biopharmaceutical properties was evaluated by several in vitro techniques. The developed SDs were able to increase the apparent solubility of the drug (up to 2-3x the equilibrium solubility) for a least 4 h. Dissolution experiments (paddle method, 75 rpm) in different pHs showed that around 80% of drug dissolved after 120 min (versus 40% of pure crystalline drug). Additionally, we demonstrated the enhanced solubility obtained via SDs could be translated into increased flux in a parallel artificial membrane permeability assay (PAMPA). In summary, the results demonstrate that SDs could be considered an interesting and unexplored strategy to improve the biopharmaceutical properties of THD, since SDs of this important drug have yet to be reported.


Asunto(s)
Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Membranas Artificiales , Talidomida/química , Talidomida/metabolismo , Química Farmacéutica , Portadores de Fármacos/administración & dosificación , Permeabilidad/efectos de los fármacos , Solubilidad , Talidomida/administración & dosificación , Difracción de Rayos X
3.
Exp Parasitol ; 134(3): 356-61, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23562884

RESUMEN

The aim of this study was to investigate the susceptibility in vitro of Trypanosoma evansi to the essential oils of andiroba (Carapa guaianensis) and aroeira (Schinus molle), in their conventional and nanostructured forms. For that, pure oils at concentrations of 0.5%, 1.0% and 2.0% were used. A negative control (untreated) and a positive control (diminazene aceturate 0.5%) were used as comparative parameters. Later, the same tests were performed, using nanoemulsions oils at concentrations of 0.5% and 1.0%. The tests were carried out in triplicates and the numbers of parasites were quantified on 1, 3 and 6 h from onset of the study. A dose-dependent reduction in the number of parasites to the forms of two oils tested was observed after 1 h. The concentration of parasites was significantly reduced at low concentrations after 3 h, as well as at 6 h no alive parasites were observed for the essential oils tested. Ours findings indicate, for the first time, that oils of andiroba and aroeira (in their conventional and nanoemulsion forms) have high activity against T. evansi in vitro, leading to the suggestion that these oils may be applied as an alternative treatment for this disease.


Asunto(s)
Anacardiaceae/química , Meliaceae/química , Aceites Volátiles/farmacología , Tripanocidas/farmacología , Trypanosoma/efectos de los fármacos , Animales , Bioensayo , Medios de Cultivo , Diminazeno/análogos & derivados , Diminazeno/farmacología , Relación Dosis-Respuesta a Droga , Emulsiones , Concentración de Iones de Hidrógeno , Ratones , Nanoestructuras , Aceites Volátiles/química , Concentración Osmolar , Extractos Vegetales/farmacología , Tripanocidas/química
4.
J Pharm Biomed Anal ; 70: 652-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22884784

RESUMEN

This study aimed to develop and validate a stability indicating LC for the determination of 5-(2-benzoylethenyl)-N-benzyl-2 methoxybenzenesulfonamide (SCD - a synthetic chalcone derivative), and evaluate the degradation profile of the compound under different stress conditions recommended by International Conference on Harmonization (ICH). Chromatographic separation was performed on a silica C18 column, methanol-water mobile phase 70:30 (v:v), pH 5.0 adjusted with the addition of trifluoroacetic acid (TFA) at a flow rate of 1.0 mL min(-1); detection by UV absorption at 330 nm. The method was validated for linearity, precision, accuracy, robustness and specificity. The SCD was subjected to forced degradation and peak photodegradation product was well separated from the pure substance, with retention times significantly different, indicating the specificity of the method. Second-order degradation kinetics of SCD was observed under photodegradation and base-induced degradation. In order to identify the product formed under photodegradation, liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed. These results indicate that the method can be successfully used in order to assay SCD in a nanoemulsion dosage form, and that this formulation has a protective effect over SCD degradation.


Asunto(s)
Chalcona/análisis , Cromatografía Líquida de Alta Presión , Nanopartículas , Fotólisis , Espectrometría de Masa por Ionización de Electrospray , Calibración , Chalcona/análogos & derivados , Chalcona/síntesis química , Chalcona/efectos de la radiación , Cromatografía Líquida de Alta Presión/normas , Formas de Dosificación , Estabilidad de Medicamentos , Emulsiones , Cinética , Modelos Lineales , Metanol/química , Nanotecnología , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Dióxido de Silicio/química , Espectrometría de Masa por Ionización de Electrospray/normas , Espectrofotometría Ultravioleta , Ácido Trifluoroacético/química , Rayos Ultravioleta , Agua/química
5.
Metab Brain Dis ; 26(2): 97-105, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21072576

RESUMEN

In the present study we investigated the effect of ovariectomy on some parameters of energy metabolism, namely Na(+),K(+)-ATPase and pyruvate kinase activities, as well as the mitochondrial respiratory chain enzymes activities succinate dehydrogenase, complex II and cytochrome c oxidase in rat striatum. The influence of soy diet rich in isoflavones on the effects elicited by ovariectomy on enzyme activities was also evaluated. Female adult Wistar rats were assigned to one of the following groups: sham (submitted to surgery without removal of the ovaries) and ovariectomized. Seven days after surgery animals were fed for 30 days on a special diet with soy protein or a standard diet with casein (control). Rats were sacrificed after treatment and the striatum was dissected. Results showed that rats subjected to ovariectomy presented a significant increase in Na(+),K(+)-ATPase, succinate dehydrogenase and complex II activities. Treatment with isoflavones-rich soy diet was able to reverse the increase of Na(+),K(+)-ATPase activity, but was not effective in reversing the changes caused by ovariectomy on succinate dehydrogenase and complex II activities. Since ovariectomy mimics postmenopausal changes, our findings suggest that dysfunction of brain energy metabolism may be related to neurological symptoms observed in some postmenopausal women.


Asunto(s)
Cuerpo Estriado/enzimología , Metabolismo Energético/fisiología , Isoflavonas/administración & dosificación , Ovariectomía , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Proteínas de Soja/administración & dosificación , Succinato Deshidrogenasa/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Posmenopausia/metabolismo , Piruvato Quinasa/metabolismo , Ratas , Ratas Wistar
6.
Metab Brain Dis ; 23(3): 243-53, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18648916

RESUMEN

Since a previous study has shown that ovariectomy impairs spatial memory, we, herein, investigate the influence of pre- and post-treatment with a soy diet on the effects elicited by ovariectomy on spatial memory. In the pre-treatment, 20-day-old female Wistar rats were first fed for 60 days on a standard diet with casein (control) or a soy diet. At 80 days of age, the animals were assigned to one of the following groups: sham (submitted to surgery without removal of ovaries) and ovariectomized. One week after surgery, the rats were submitted to behavioral testing. In the post-treatment, 80-day-old female rats were assigned to one of the following groups: sham and ovariectomized. One week after surgery, animals were fed for 30 days with the same diet described above. Then, rats were submitted to water maze testing. Pre-treatment for two months before ovariectomy with the soy diet effectively prevented the increase in latency in finding the platform on the fifth day of training in the ovariectomized group. Ovariectomized rats subjected to soy diet post-treatment reversed the increase in latency to find the platform in the ovariectomized group on the fifth day of training and, the decrease in the time spent in target quadrant, the increase in the time spent in opposite quadrant and the latency to cross the platform location. Results show that both pre- and post-treatment protected against the impairment of memory, caused by ovariectomy. Post-treatment reversed various parameters of memory reference, indicating that post-treatment was more efficient than pre-treatment. Based on these findings, we suggest that soy diet (rich in isoflavones) may represent a novel therapeutic strategy to prevent or to treat cognitive symptoms found in some menopausal women.


Asunto(s)
Glycine max/química , Isoflavonas/uso terapéutico , Memoria/efectos de los fármacos , Memoria/fisiología , Ovariectomía/psicología , Percepción Espacial/efectos de los fármacos , Percepción Espacial/fisiología , Animales , Peso Corporal/efectos de los fármacos , Dieta , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Femenino , Aprendizaje por Laberinto/efectos de los fármacos , Ratas , Ratas Wistar
7.
Metab Brain Dis ; 22(2): 156-71, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17514415

RESUMEN

Since a previous study demonstrated that ovariectomized rats present an activation of Na(+), K(+)-ATPase and acetylcholinesterase (AChE) activities, in the present study we investigated the influence of vitamins E plus C or soy isoflavones on the effects elicited by ovariectomy on the activities of these enzyme in hippocampus of ovariectomized rats. We also determined the effect of the same compounds on the reduction of serum butyrylcholinesterase (BuChE) activity caused by ovariectomy. Female adult Wistar rats were assigned to one of the following groups: sham (submitted to surgery without removal of the ovaries) and ovariectomized. Seven days after surgery, animals were treated for 30 days with a single daily intraperitoneous injection of vitamins E (40 mg/kg) plus C (100 mg/kg) or saline (control). In another set of experiments, the rats were fed for 30 days on a special diet with soy protein or a standard diet with casein (control). Rats were sacrificed after treatments and the hippocampus was dissected and serum was separated. Data demonstrate that vitamins E plus C reversed the activation of Na(+), K(+)-ATPase and AChE in hippocampus of ovariectomized rats. Conversely, soy protein supplementation reversed the increase of AChE activity, but not of Na(+), K(+)-ATPase activity, caused by ovariectomized group. Neither treatment was able to reverse the reduction of serum BuChE activity. Furthermore, treatments with vitamins E plus C or soy were unable to reverse the decrease in estradiol levels caused by ovariectomy. Our findings show that the treatment with vitamins E plus C significantly reversed the effect of ovariectomy on hippocampal Na(+), K(+)-ATPase and AChE activities. However, a soy diet that was rich in isoflavones was able to reverse just the increase of AChE. Neither treatment altered the reduction in serum BuChE activity. Taken together, these vitamins and soy may have a protective role against the possible brain dysfunction observed in some menopause women. Vitamins E plus C and soy isoflavones may be a good alternative as a novel therapeutic strategy.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Colinesterasas/metabolismo , Genisteína/administración & dosificación , Hipocampo/enzimología , Isoflavonas/administración & dosificación , Ovariectomía , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Vitamina E/administración & dosificación , Animales , Femenino , Ratas , Ratas Wistar
8.
Metab Brain Dis ; 22(2): 172-82, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17473966

RESUMEN

In the present study we investigated the effect of chronic administration of methionine, a metabolite accumulated in many inherited pathological conditions such as methionine adenosyltransferase deficiency and homocystinuria, on some parameters of oxidative stress, namely thiobarbituric acid reactive substances (TBARS), catalase activity and total thiol content, as well as on Na(+),K(+)-ATPase activity in rat hippocampus. For chronic treatment, rats received subcutaneous injections of methionine (1.34-2.68 mumol/g of body weight), twice a day, from the 6th to the 28th day of age and controls received saline. Animals were killed 12 h after the last injection. Results showed that chronic hypermethioninemia significantly increased TBARS, decreased Na(+),K(+)-ATPase activity but did not alter catalase and total thiol content. Since chronic hypermethioninemia altered TBARS and Na(+),K(+)-ATPase activity at 12 h after methionine administration, we also investigated the effect of acute administration of this amino acid on the same parameters studied after chronic methionine administration. For acute treatment,29-day-old rats received one single injection of methionine (2.68 mumol/g of body weight) or saline and were killed 1, 3 or 12 h later. Results showed that rats subjected to acute hypermethioninemia presented a reduction of Na(+),K(+)-ATPase activity and an increase in TBARS when the animals were killed at 3 and 12 h, but not at 1 h, after methionine administration. These data indicate that hypermethioninemia increases lipid peroxidation which may, at least partially, explain the effect of methionine on the reduction in Na(+),K(+)-ATPase activity. If confirmed in human beings, our findings could suggest that the induction of oxidative stress and the inhibition of Na(+),K(+)-ATPase activity caused by methionine might contribute to the neurophysiopathology observed in patients with severe hypermethioninemia.


Asunto(s)
Hipocampo/enzimología , Metionina/sangre , Estrés Oxidativo , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Animales , Peroxidación de Lípido , Ratas , Ratas Wistar , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
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