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1.
Eur J Pharm Sci ; 151: 105397, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32485345

RESUMO

The development of cognitive impairment may be related to high levels of plasma cholesterol and obesity. Simvastatin (SV) and lovastatin (LV) are drugs that can potentially be used for the treatment of cognitive deficit. This study aimed to develop and characterize lipid-core nanocapsules (LNC) containing SV (SV-LNC) or LV (LV-LNC), evaluating the effects of SV-LNC in an animal model of cognitive deficit. The formulations SV-LNC and LV-LNC presented a particle average size around 200 nm, a low-polydispersity index, and negative zeta potential. Analysis of differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy showed that there is no reaction among LNC components: LV was crystallized in the suspensions, and SV was molecularly dispersed. The encapsulation efficiency of the SV was high (98.9 ± 1.4%), while that of the LV was low (21.5 ± 1.5%).Based on these results, SV-LNC was used in the preclinical studies. Animals fed with a hyperlipidic diet (HD) developed obesity, hypercholesterolemia, and cognitive impairment, which was corroborated by the brain lesions indicated by histological analysis of some of the animals that received the high-fat diet. We observed that free simvastatin (CS3) was able to reduce the enzymatic activity of pyruvate kinase, an important enzyme for brain energy homeostasis, without affecting the memory of the animals that received a standard diet. However, it failed to improve the cognitive damage caused by a diet high in cholesterol and saturated fats. On the other hand, when simvastatin is "camouflaged" in the lipid-core nanocapsules (HNS3), this cognitive impairment improves. Thus, SV-LNC is a promising alternative therapy for the treatment of cognitive impairment.


Assuntos
Disfunção Cognitiva , Hipercolesterolemia , Nanocápsulas , Animais , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Hipercolesterolemia/tratamento farmacológico , Lipídeos , Obesidade/tratamento farmacológico , Ratos , Sinvastatina
2.
AAPS PharmSciTech ; 21(1): 32, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31863211

RESUMO

Lipid nanoparticles (LNs) are traditional systems able to effectively increase skin hydration. However, due to its reduced viscosity, LNs suspensions are less attractive for skin administration. To overcome this disadvantage, the LN were incorporated in the semi-solid formulation is easy manipulation. This study demonstrated that it is possible to obtain novel LN-loaded fucoxanthin (LN-FUCO) for topical administration containing a combination of bacuri butter and tucumã oil prepared by high shear homogenization for improved stability. The particle size was found to be 243.0 nm and the entrapment efficiency up to 98% of FUCO was incorporated and achieved the suitability of formula. The LN-FUCO hydrogel characteristics of slight acidity, drug content near 100%, and nanometric mean size assure to this formulation high compatibility to dermal application. Photostability assay by UVA, LN-FUCO, and LN-FUCO hydrogel improved photostability and conferred greater protection against FUCO degradation. The results obtained from in vitro skin permeation studies presented a significant difference between LN-FUCO hydrogel and FUCO (p < 0.05), with no detection of the drug in the receptor medium. Therefore, high shear homogenization is demonstrated to be a simple, available, and effective method to prepare high-quality LN-FUCO hydrogel for topical application.


Assuntos
Lipídeos/química , Nanopartículas , Xantofilas/química , Administração Cutânea , Animais , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Hidrogéis/metabolismo , Tamanho da Partícula , Absorção Cutânea
3.
J Microencapsul ; 36(4): 317-326, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31159613

RESUMO

Aims: Lipid-core nanocapsules (LNCs) loaded with simvastatin (SV, SV-LNC) or lovastatin (LV, LV-LNC) were formulated for pulmonary administration. Methods: The LNC suspensions were characterized physicochemically, their stability was evaluated, and drug delivery by the pulmonary route was tested in vitro. Results: The loaded LNCs had a particle size close to 200 nm, a low polydispersity index, and a zeta potential around -20 mV. The encapsulation efficiency was high for SV (99.21 ± 0.7%) but low for LV (20.34 ± 1.2%). SV release from nanocapsules was slower than it was from SV in solution, with a monoexponential release profile, and the drug emitted and aerosol output rate was higher for SV-LNCs (1.58 µg/s) than for SV in suspension (0.54 µg/s). Conclusions: SV-LNCs had a median aerodynamic diameter of 3.51 µm and a highly respirable fraction (61.9%), indicating that nanoparticles are a suitable system for efficient delivery of simvastatin to the lung.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Lovastatina/administração & dosagem , Nanocápsulas/química , Sinvastatina/administração & dosagem , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Lipídeos/química , Lovastatina/química , Nebulizadores e Vaporizadores , Tamanho da Partícula , Sinvastatina/química
4.
Microb Pathog ; 97: 119-24, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241236

RESUMO

Candida albicans does not only occur in the free living planktonic form but also grows in surface-attached biofilm communities. Moreover, these biofilms appear to be the most common lifestyle and are involved in the majority of human Candida infections. Nanoparticles can be used as an alternative to conventional antimicrobial agents and can also act as carriers for antibiotics and other drugs. In view of this, the aim of the study was develop, characterize and verify the anti-biofilm potential of GML Nanocapsules against C. albicans. The GML Nanocapsules showed mean diameter of 193.2 nm, polydispersion index of 0.044, zeta potential of -23.3 mV and pH 6.32. The microdilution assay showed MIC of 15.5 µg mL(-1) to GML Nanocapsules and 31.25 µg mL(-1) to GML. The anti-biofilm assay showed the significantly reduction of biomass of C. albicans biofilm treated with GML Nanocapsules while the GML does not exhibit effect. The kinetic assay demonstrated that at 48 h, the GML Nanocapsules reduce 94% of formed biofilm. The positive results suggest the promisor alternative for this public health problem that is biofilm infections.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Lauratos/farmacologia , Monoglicerídeos/farmacologia , Nanocápsulas , Candida albicans/fisiologia , Testes de Sensibilidade Microbiana
5.
Biomed Chromatogr ; 30(2): 155-62, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26053258

RESUMO

A simple, sensitive, precise and linear method by liquid chromatography was established for simultaneous determination and quantification of naringin and naringenin in polymeric nanoparticles. The method results in excellent separation in <11 min and with a peak purity of both flavonoids. The analyses were performed using a C18 column (4.6 × 150 mm, 5 µm), at a 1 mL/min flow rate. The mobile phase consisted of a gradient of acetonitrile-water (pH 4.0; v/v) at a temperature of 25°C. The nanoparticles were prepared according to the method of interfacial deposition of a pre-formed polymer. The method were validated in compliance with guidelines, and was found to be linear in the 1-40 µg/mL concentration range for both naringin and naringenin (r > 0.99). Repeatability was determined at three concentration levels, obtaining an RSD (%) <0.9%, and the accuracy of the method was >98%. The photodegradation kinetics was determined for naringin; the coefficient that best represents degradation was of first order and naringenin presented a zero-order kinetics. To our knowledge, a rapid and sensitive method for naringin and naringenin in polymeric nanoparticles has not been published elsewhere and this method is applicable to simultaneous evaluation of flavonoids.


Assuntos
Cromatografia Líquida/métodos , Flavanonas/análise , Nanopartículas/química , Estabilidade de Medicamentos , Flavanonas/química , Flavanonas/isolamento & purificação , Fotólise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Pharm Dev Technol ; 12(5): 463-71, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17963146

RESUMO

Microparticles of poly(epsilon-caprolactone) and of its blend with Eudragit S100 were prepared by emulsion/solvent evaporation technique to provide controlled release and gastro-resistance for an acid labile drug. This drug was sodium pantoprazole, a proton pump inhibitor. Both formulations were successfully prepared, but only the microparticles prepared with the blend were capable of stabilizing the drug in the acid medium. Furthermore, this formulation showed in vivo protection of stomachs against ulceration caused by ethanol in rats. These microparticles were tabletted, and the tablets demonstrated slower drug release and higher acid protection than the microparticles before tabletting.


Assuntos
2-Piridinilmetilsulfinilbenzimidazóis/farmacocinética , Poliésteres/química , Ácidos Polimetacrílicos/química , 2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , 2-Piridinilmetilsulfinilbenzimidazóis/química , Acetona/química , Administração Oral , Animais , Antiulcerosos/administração & dosagem , Antiulcerosos/química , Antiulcerosos/farmacocinética , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Concentração de Íons de Hidrogênio , Masculino , Microscopia Eletrônica de Varredura , Óleo Mineral/química , Pantoprazol , Tamanho da Partícula , Ratos , Ratos Wistar , Úlcera Gástrica/prevenção & controle , Propriedades de Superfície , Comprimidos com Revestimento Entérico
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