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1.
J Control Release ; 248: 117-124, 2017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-28077264

RESUMEN

Lycopene is a natural anti-oxidant that has attracted much attention due to its varied applications such as protection against loss of bone mass, chronic diseases, skin cancer, prostate cancer, and cardiovascular disease. However, high instability and extremely low oral bioavailability limit its further clinical development. We selected a green tea catechin derivative, oligomerized (-)-epigallocatechin-3-O-gallate (OEGCG) as a carrier for oral lycopene delivery. Lycopene-loaded OEGCG nanoparticles (NPs) were prepared by a nano-precipitation method, followed by coating with chitosan to form a shell. This method not only can easily control the size of the NP to be around 200nm to improve its bioavailability, but also can effectively protect the lycopene against degradation due to EGCG's anti-oxidant property. OEGCG was carefully characterized with nuclear magnetic resonance spectroscopy and mass spectrometry. Lycopene-loaded polylactic-co-glycolic acid (PLGA) NPs were prepared by the same method. Chitosan-coated OEGCG/lycopene NPs had a diameter of 152±32nm and a ζ-potential of 58.3±4.2mv as characterized with transmission electron microscopy and dynamic light scattering. The loading capacity of lycopene was 9% and encapsulation efficiency was 89%. FT-IR spectral analysis revealed electrostatic interaction between OEGCG and chitosan. Freeze drying of the NPs was also evaluated as a means to improve shelf life. Dynamic light scattering data showed that no aggregation occurred, and the size of the NP increased 1.2 times (Sf/Si ratio) in the presence of 10% sucrose after freeze drying. The in vitro release study showed slow release of lycopene in simulated gastric fluid at acidic pH and faster release in simulated intestinal fluid. In an in vivo study in mice, lycopene pharmacokinetic parameters were improved by lycopene/OEGCG/chitosan NPs, but not improved by lycopene/PLGA/chitosan NPs. The self-assembled nanostructure of OEGCG combined with lycopene may be a promising application in oral drug delivery in various indications.


Asunto(s)
Antioxidantes/administración & dosificación , Carotenoides/administración & dosificación , Catequina/análogos & derivados , Portadores de Fármacos/química , Nanopartículas/química , Té/química , Administración Oral , Animales , Antioxidantes/farmacocinética , Disponibilidad Biológica , Carotenoides/farmacocinética , Catequina/química , Licopeno , Masculino , Ratones Endogámicos C57BL , Nanopartículas/ultraestructura
2.
Bone ; 83: 127-140, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26549245

RESUMEN

Lycopene supplementation decreases oxidative stress and exhibits beneficial effects on bone health, but the mechanisms through which it alters bone metabolism in vivo remain unclear. The present study aims to evaluate the effects of lycopene treatment on postmenopausal osteoporosis. Six-month-old female Wistar rats (n=264) were sham-operated (SHAM) or ovariectomized (OVX). The SHAM group received oral vehicle only and the OVX rats were randomized into five groups receiving oral daily lycopene treatment (mg/kg body weight per day): 0 OVX (control), 15 OVX, 30 OVX, and 45 OVX, and one group receiving alendronate (ALN) (2µg/kg body weight per day), for 12weeks. Bone densitometry measurements, bone turnover markers, biomechanical testing, and histomorphometric analysis were conducted. Micro computed tomography was also used to evaluate changes in microarchitecture. Lycopene treatment suppressed the OVX-induced increase in bone turnover, as indicated by changes in biomarkers of bone metabolism: serum osteocalcin (s-OC), serum N-terminal propeptide of type 1 collagen (s-PINP), serum crosslinked carboxyterminal telopeptides (s-CTX-1), and urinary deoxypyridinoline (u-DPD). Significant improvement in OVX-induced loss of bone mass, bone strength, and microarchitectural deterioration was observed in lycopene-treated OVX animals. These effects were observed mainly at sites rich in trabecular bone, with less effect in cortical bone. Lycopene treatment down-regulated osteoclast differentiation concurrent with up-regulating osteoblast together with glutathione peroxidase (GPx) catalase (CAT) and superoxide dismutase (SOD) activities. These findings demonstrate that lycopene treatment in OVX rats primarily suppressed bone turnover to restore bone strength and microarchitecture.


Asunto(s)
Resorción Ósea/tratamiento farmacológico , Resorción Ósea/fisiopatología , Huesos/patología , Huesos/fisiopatología , Carotenoides/uso terapéutico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/fisiopatología , 8-Hidroxi-2'-Desoxicoguanosina , Absorciometría de Fotón , Animales , Biomarcadores/sangre , Fenómenos Biomecánicos/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Remodelación Ósea/efectos de los fármacos , Resorción Ósea/sangre , Resorción Ósea/diagnóstico por imagen , Huesos/diagnóstico por imagen , Huesos/efectos de los fármacos , Carotenoides/sangre , Carotenoides/farmacología , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangre , Diáfisis/diagnóstico por imagen , Diáfisis/efectos de los fármacos , Diáfisis/fisiopatología , Modelos Animales de Enfermedad , Enzimas/sangre , Femenino , Fémur/diagnóstico por imagen , Fémur/efectos de los fármacos , Fémur/fisiopatología , Hormonas/sangre , Humanos , Húmero/diagnóstico por imagen , Húmero/efectos de los fármacos , Húmero/fisiopatología , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/efectos de los fármacos , Vértebras Lumbares/fisiopatología , Licopeno , Minerales/sangre , Tamaño de los Órganos/efectos de los fármacos , Osteoporosis Posmenopáusica/sangre , Ratas Wistar , Tibia/diagnóstico por imagen , Tibia/efectos de los fármacos , Tibia/fisiopatología , Útero/efectos de los fármacos , Útero/patología , Microtomografía por Rayos X
3.
Bone ; 50(3): 713-22, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22178778

RESUMEN

This study was designed to identify independent predictors of all osteoporosis-related fractures (ORFs) among healthy Saudi postmenopausal women. We prospectively followed a cohort of 707 healthy postmenopausal women (mean age, 61.3±7.2 years) for 5.2±1.3 years. Data were collected on demographic characteristics, medical history, personal and family history of fractures, lifestyle factors, daily calcium intake, vitamin D supplementation, and physical activity score. Anthropometric parameters, total fractures (30.01 per 1000 women/year), special physical performance tests, bone turnover markers, hormone levels, and bone mineral density (BMD) measurements were performed. The final model consisted of seven independent predictors of ORFs: [lowest quartile (Q(1)) vs highest quartile (Q(4))] physical activity score (Q(1) vs Q(4): ≤12.61 vs ≥15.38); relative risk estimate [RR], 2.87; (95% confidence interval [CI]: 1.88-4.38); age≥60 years vs age<60 years (RR=2.43; 95% CI: 1.49-3.95); hand grip strength (Q(1) vs Q(4): ≤13.88 vs ≥17.28 kg) (RR=1.88; 95% CI: 1.15-3.05); BMD total hip (Q(1) vs Q(4): ≤0.784 vs 0.973 g/cm(2)) (RR=1.86; 95% CI: 1.26-2.75); dietary calcium intake (Q(1) vs Q(4): ≤391 vs ≥648 mg/day) (RR=1.66; 95% CI: 1.08-2.53); serum 25(OH)D (Q(1) vs Q(4): ≤17.9 vs ≥45.1 nmol/L) (RR=1.63; 95% CI: 1.06-2.51); and past year history of falls (RR=1.61; 95% CI: 1.06-2.48). Compared with having none (41.9% of women), having three or more clinical risk factors (4.8% of women) increased fracture risk by more than 4-fold, independent of BMD. Having three or more risk factors and being in the lowest tertile of T-score of [total hip/lumbar spine (L1-L4)] was associated with a 14.2-fold greater risk than having no risk factors and being in the highest T-score tertile. Several clinical risk factors were independently associated with all ORFs in healthy Saudi postmenopausal women. The combination of multiple clinical risk factors and low BMD is a very powerful indicator of fracture risk.


Asunto(s)
Densidad Ósea/fisiología , Fracturas Óseas/etiología , Osteoporosis Posmenopáusica/complicaciones , Fracturas Osteoporóticas/etiología , Anciano , Calcio de la Dieta , Estudios de Cohortes , Femenino , Humanos , Estilo de Vida , Persona de Mediana Edad , Posmenopausia , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Arabia Saudita , Salud de la Mujer
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