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1.
Phytomedicine ; 84: 153502, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33647775

RESUMEN

BACKGROUND: Transforming growth factor­ß (TGF-ß) signaling is a crucial inducer of tissue fibrosis and extracellular matrix accumulation and a vital suppressor of epithelial cell proliferation and cancer metastasis. The nature of this multifunctional cytokine has prompted the development of TGF-ß signaling inhibitors as therapeutic agents. Our research group has recently isolated the polyprenylated polycyclic acylphloroglucinol garcimultiflorone K (GMK) from the stems of Garcinia multiflora; GMK exhibits antiangiogenic activity in endothelial cells. PURPOSE: In the current study, we aimed to explore the antitumor effect and detailed mechanisms of Garcimultiflorone K in hepatocellular carcinoma cells. METHODS: Cell proliferation and viability were evaluated using the MTT assay. The migratory ability of HepG2 cells was measured using wound healing assays. The inhibitory effect of GMK against the nuclear translocation of Smad by TGF-ß was assessed through immunofluorescence staining and Western blotting. To investigate TGF-ß-dependent gene expression profiles upon GMK stimulation, RNA transcript levels were determined using reverse transcription polymerase chain reaction. The effects of GMK in Smad2-driven transcriptomic activities were studied using a reporter gene assay. Protein levels were detected using Western blotting. RESULTS: Our data revealed that GMK inhibited TGF-ß-induced cellular responses, including Smad protein phosphorylation, cell migration, and extracellular matrix production, during epithelial-mesenchymal transition (EMT). Mechanistic studies further demonstrated that GMK suppressed TGF-ß signaling by downregulating TGF-ß receptor II (TßRII). CONCLUSION: These findings elucidate that TßRII expression in hepatic cells can be specifically suppressed by GMK to attenuate metastasis and the disease-promoting effects of EMT, representing a therapeutic approach.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Floroglucinol/farmacología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Garcinia/química , Células Hep G2 , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/patología , Humanos , Neoplasias Hepáticas/patología , Ratones , Fosforilación/efectos de los fármacos , Ratas , Receptores de Factores de Crecimiento Transformadores beta/genética , Transducción de Señal/efectos de los fármacos
2.
Medicine (Baltimore) ; 98(17): e15368, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31027125

RESUMEN

Aortic aneurysm (AA) is a disease with substantially higher health care costs and very high mortality upon rupture. Statins have a non-lipid-lowering pleiotropic mechanism that may be beneficial for AA in disease progression and improvement of AA patient outcomes. Previous studies have been conducted with some limitations and without considering immortal time bias, lag time, and adherence. The aim of our study was to analyze the effect of statin use on AA postoperation after controlling for these factors.All postoperative patients with a diagnosis of AA in Taiwan from 2004 to 2012 were included from the National Health Insurance Research Database. We excluded patients without computed tomography within 1 year after diagnosis and those who died within 30 days after the operation. We also analyzed the medication, medication possession ratio (MPR), immortal time bias, and lag time. Statin users were defined as those using statins for more than 30 days. Primary composite outcomes included mortality, reoperation for AA and rehospitalization for AA during the study period.Among the whole study population (n = 1633), 199/1633 (12.19%) patients were statin users, while the others (n = 1434) were not. Mortality was higher in statin nonusers than in statin users, with a mortality rate of 40% versus 22.61% (P < .0001). There was no significant difference in reoperation or rehospitalization for AA.Statin use may be beneficial for AA patients in our observational study. Prospective randomized controlled studies are needed to define the effect of statin therapy in this population.


Asunto(s)
Aneurisma de la Aorta/epidemiología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Complicaciones Posoperatorias/epidemiología , Anciano , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud , Estudios Retrospectivos , Taiwán
3.
Colloids Surf B Biointerfaces ; 161: 121-128, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29055864

RESUMEN

The aim of the present study was to design a microemulsion for catechin topical application. A mixture experimental design with five independent variables (X1: oil, X2: surfactant, X3: catechin, X4: cosurfactant and X5: water) was developed, and the response surface methodology was used to study the effect of formulation components on physiochemical characteristics and penetration capacity of a catechin-loaded microemulsion, and to obtain an optimal microemulsion formulation. The results showed that the drug-loaded microemulsion formation and characteristics were related to many parameters of the components. The transdermal amounts in receiver cells and skin deposition amount remarkably increased about 4.1-111.6-fold and 0.6-7.6-fold respectively. The lag time was significantly shortened from 10h to 1.0-6.7h. The optimal formulation with 20% surfactant, 30% cosurfactant and 2.6% Catechin was subjected to stability and irritation tests. The results showed that the physicochemical characteristics and catechin level of the drug-loaded microemulsion did not show significant degradation after 3 months of storage at 25°C.The catechin-loaded microemulsion did not cause significant irritation compared to the water-treated group.


Asunto(s)
Catequina/administración & dosificación , Emulsiones/química , Absorción Cutánea , Piel/metabolismo , Administración Cutánea , Animales , Catequina/química , Catequina/farmacocinética , Fenómenos Químicos , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Estabilidad de Medicamentos , Interacciones Hidrofóbicas e Hidrofílicas , Ratas Sprague-Dawley , Piel/citología , Tensoactivos/química , Agua/química
4.
PLoS One ; 10(10): e0140249, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26448474

RESUMEN

Transforming growth factor-ß (TGF-ß) responsiveness in cultured cells can be modulated by TGF-ß partitioning between lipid raft/caveolae- and clathrin-mediated endocytosis pathways. Lipid rafts are plasma membrane microdomains with an important role in cell survival signaling, and cholesterol is necessary for the lipid rafts' structure and function. Euphol is a euphane-type triterpene alcohol that is structurally similar to cholesterol and has a wide range of pharmacological properties, including anti-inflammatory and anti-cancer effects. In the present study, euphol suppressed TGF-ß signaling by inducing TGF-ß receptor movement into lipid-raft microdomains and degrading TGF-ß receptors.


Asunto(s)
Lanosterol/análogos & derivados , Microdominios de Membrana/metabolismo , Extractos Vegetales/farmacología , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/fisiología , Línea Celular Tumoral , Euphorbia/química , Fibronectinas/genética , Fibronectinas/metabolismo , Expresión Génica , Humanos , Lanosterol/farmacología , Fosforilación , Procesamiento Proteico-Postraduccional , Transporte de Proteínas , Proteolisis , Neoplasias Gástricas , Activación Transcripcional
5.
ScientificWorldJournal ; 2013: 856967, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24068886

RESUMEN

The purpose of this study was to develop and optimize an isotretinoin oil-based capsule with specific dissolution pattern. A three-factor-constrained mixture design was used to prepare the systemic model formulations. The independent factors were the components of oil-based capsule including beeswax (X1), hydrogenated coconut oil (X2), and soybean oil (X3). The drug release percentages at 10, 30, 60, and 90 min were selected as responses. The effect of formulation factors including that on responses was inspected by using response surface methodology (RSM). Multiple-response optimization was performed to search for the appropriate formulation with specific release pattern. It was found that the interaction effect of these formulation factors (X1X2, X1X3, and X2X3) showed more potential influence than that of the main factors (X1, X2, and X3). An optimal predicted formulation with Y(10 min), Y(30 min), Y(60 min), and Y(90 min) release values of 12.3%, 36.7%, 73.6%, and 92.7% at X1, X2, and X3 of 5.75, 15.37, and 78.88, respectively, was developed. The new formulation was prepared and performed by the dissolution test. The similarity factor f2 was 54.8, indicating that the dissolution pattern of the new optimized formulation showed equivalence to the predicted profile.


Asunto(s)
Cápsulas/síntesis química , Isotretinoína/química , Aceite de Coco , Sistemas de Liberación de Medicamentos , Hidrogenación , Aceites de Plantas/química , Aceite de Soja/química , Factores de Tiempo , Ceras/química
6.
Phytochem Anal ; 17(6): 439-46, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17144253

RESUMEN

A simple and reliable high-performance liquid chromatographic method with ultraviolet detection (280 nm) has been developed for the simultaneous analysis of 12 bioactive components in San-huang-xie-xin-tang (SHXXT), a traditional Chinese medicine containing Rhei rhizome, Coptidis rhizome and Scutellariae radix. A relatively simple extraction procedure was employed and optimised, and separation of the components was obtained within 1 h using a reversed-phase column under gradient elution with acetonitrile and a buffer containing 0.01 M sodium 1-pentanesulphonate (pH 3). The lower limit of detection for the analytes ranged from 25 to 75 ng/mL. The correlation coefficients associated with each calibration curve were greater than 0.99. The precision and accuracy of the method ranged from 1.0 to 10.5% at low concentration levels, 0.8 to 8.7% at medium levels and 1.2 to 5.8% at high levels. In commercial products of SHXXT, baicalin and berberine were present in the highest amounts with levels up to 4.0 and 3.3%, respectively, in one sample. The HPLC method was able rapidly and efficiently to analyse constituents in crude herb and traditional Chinese medicinal preparations containing Rhei rhizome, Coptidis rhizome and Scutellariae radix.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , Calibración , Estructura Molecular
7.
J Ethnopharmacol ; 96(1-2): 99-106, 2005 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-15588656

RESUMEN

San-Huang-Xie-Xin-Tang (SHXT) is a traditional Chinese medicinal formula containing Coptidis rhizoma, Scutellariae radix and Rhei rhizoma. The present study aimed to determine the preventive effects of standardized SHXT on lipopolysaccharides (LPS)-induced arterial hypotension, protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), cytokines formation and prostaglandin E2 (PGE2) production. LPS-induced activation of iNOS has been recognized to increase cytokines and nitric oxide, some of them play predominant roles in sepsis. Intravenous injection of LPS (10 mg/kg) caused a marked decrease of the mean arterial pressure in normotensive rats. However, the LPS-induced arterial hypotension was inhibited by SHXT (0.01 and 0.03 g/kg), when it was given 30 min before LPS. Moreover, plasma level of cytokines and PGE2 were lowered by SHXT. In RAW 264.7 cells, SHXT (20-200 microg/ml) dose-dependently inhibited LPS (1 microg/ml)-induced iNOS and COX-2 expression, and it also significantly decreased LPS-induced cytokines in a dose-dependent manner. In conclusion, our data suggest that SHXT prevented LPS-induced arterial hypotension, which might be mediated through its inhibition activities on the expression of iNOS and COX-2, cytokines formation and PGE2 production. Therefore, its protection activity against LPS-induced arterial hypotension and inflammatory mediators release might be beneficial in the treatment of endotoxin shock and/or associated inflammation.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Hipotensión/prevención & control , Mediadores de Inflamación/antagonistas & inhibidores , Fitoterapia , Animales , Presión Sanguínea/efectos de los fármacos , Western Blotting , Línea Celular , Supervivencia Celular , Ciclooxigenasa 2 , Citocinas/sangre , Citocinas/metabolismo , Dinoprostona/sangre , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Hipotensión/inducido químicamente , Inyecciones Intravenosas , Lipopolisacáridos , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Prostaglandina-Endoperóxido Sintasas/metabolismo , Ratas , Ratas Wistar , Factores de Tiempo
8.
Eur J Pharm Sci ; 19(2-3): 115-22, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12791413

RESUMEN

The aim of the present work was to prepare and evaluate the sustained release of potassium chloride formulations. Eudragit RS and/or RL loaded with potassium chloride microspheres were prepared by a solvent evaporation method. The effect of sustained release of Eudragit microspheres was evaluated by an in vitro dissolution test and in vivo oral absorption study, and the results were compared to a commercial product (Slow-K). The results showed that Eudragit microspheres loaded with potassium chloride can be easily prepared and satisfactory results obtained considering the size distribution and shapes of microspheres by incorporating aluminum stearate. The encapsulation efficiency and loading capacity were about 84-90% and 27%, respectively. Moreover, the Eudragit RS (30-45 mesh) and Eudragit RS/RL (20-30 mesh) microspheres showed a similar sustained release effect of commercial product via in vitro dissolution and in vivo oral absorption study.


Asunto(s)
Microesferas , Ácidos Polimetacrílicos/síntesis química , Ácidos Polimetacrílicos/farmacocinética , Cloruro de Potasio/síntesis química , Cloruro de Potasio/farmacocinética , Animales , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/farmacocinética , Diseño de Fármacos , Evaluación Preclínica de Medicamentos/métodos , Masculino , Conejos , Solubilidad
9.
J Biomed Mater Res ; 59(3): 438-49, 2002 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-11774301

RESUMEN

A novel bilayer chitosan membrane was prepared by a combined wet/dry phase inversion method and evaluated as a wound dressing. This new type of bilayer chitosan wound dressing, consisting of a dense upper layer (skin layer) and a sponge-like lower layer (sublayer), is very suitable for use as a topical delivery of silver sulfadiazine (AgSD) for the control of wound infections. Physical characterization of the bilayer wound dressing showed that it has excellent oxygen permeability, that it controls the water vapor transmission rate, and that it promotes water uptake capability. AgSD dissolved from bilayer chitosan dressings to release silver and sulfadiazine. The release of sulfadiazine from the bilayer chitosan dressing displayed a burst release on the first day and then tapered off to a much slower release. However, the release of silver from the bilayer chitosan dressing displayed a slow release profile with a sustained increase of silver concentration. The cultures of Pseudomonas aeruginosa and Staphylococcus aureus in agar plates showed effective antimicrobial activity for 1 week. In vivo antibacterial tests confirmed that this wound dressing is effective for long-term inhibition of the growth of Pseudomonas aeruginosa and Staphylococcus aureus at an infected wound site. The results in this study indicate that the AgSD-incorporated bilayer chitosan wound dressing may be a material with potential antibacterial capability for the treatment of infected wounds.


Asunto(s)
Quitina/análogos & derivados , Quitina/uso terapéutico , Infección de Heridas/terapia , Administración Tópica , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Antiinfecciosos Locales/administración & dosificación , Antiinfecciosos Locales/farmacocinética , Vendajes/microbiología , Vendajes/normas , Quitosano , Sistemas de Liberación de Medicamentos/métodos , Masculino , Membranas Artificiales , Pruebas de Sensibilidad Microbiana , Ratas , Ratas Wistar , Sulfadiazina de Plata/administración & dosificación , Sulfadiazina de Plata/farmacocinética , Cicatrización de Heridas/efectos de los fármacos
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