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1.
Int J Pharm ; 471(1-2): 92-102, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-24810240

RESUMO

Lecithin-linker microemulsions are formulations produced with soybean lecithin in combination with a highly lipophilic (lipophilic linker) and highly hydrophilic (hydrophilic linkers) surfactant-like additives. In this work, lecithin-linker systems were formulated to produce self-emulsifying delivery systems for ß-carotene and ß-sitosterol. The concentration of the lipophilic linker, sorbitan monooleate, was adjusted to minimize the formation of liquid crystals. The concentration of hydrophilic linkers, decaglyceryl caprylate/caprate and PEG-6-caprylic/capric glycerides, was gradually increased (scanned) until single phase clear microemulsions were obtained. For these scans, the oil (ethyl caprate) to water ratio was set to 1. The single phase, clear microemulsions were diluted with fed-state simulated intestinal fluid (FeSSIF) and produced stable emulsions, with drop sizes close to 200 nm. Using pseudo-ternary phase diagrams to evaluate the process of dilution of microemulsion preconcentrates (mixtures of oil, lecithin and linkers with little or no water) with FeSSIF, it was determined that self-emulsifying systems are obtained when the early stages of the dilution produce single phase microemulsions. If liquid crystals or multiple phase systems are obtained during those early stages, then the emulsification yields unstable emulsions with large drop sizes. An in vitro permeability study conducted using a Flow-Thru Dialyzer revealed that stable emulsions with drop sizes of 150-300 nm produce large and irreversible permeation of ß-carotene to sheep intestine. On the other hand, unstable emulsions produced without the linker combination separated in the dialyzer chamber.


Assuntos
Suplementos Nutricionais , Portadores de Fármacos/química , Lecitinas/química , Sitosteroides/administração & dosagem , Tensoativos/química , beta Caroteno/administração & dosagem , Animais , Química Farmacêutica , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Técnicas In Vitro , Jejuno/metabolismo , Estrutura Molecular , Permeabilidade , Transição de Fase , Ovinos , Sitosteroides/farmacocinética , Glycine max/química , Tensão Superficial , beta Caroteno/farmacocinética
2.
Am J Clin Nutr ; 95(3): 564-71, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22301925

RESUMO

BACKGROUND: Recent analyses have challenged the effectiveness of soy foods as part of a cardiovascular risk reduction diet. OBJECTIVE: The objective of the study was to show whether equol status determines the effectiveness of soy foods to lower LDL cholesterol and to raise HDL cholesterol. DESIGN: Eighty-five hypercholesterolemic men and postmenopausal women (42 men, 43 women) participated in 1 of 3 studies that represented a range of soy interventions and that followed the same general protocol at a Canadian university hospital research center. Soy foods were provided for 1 mo at doses of 30-52 g/d for the 3 studies as follows: 1) soy foods with either high-normal (73 mg/d) or low (10 mg/d) isoflavones, 2) soy foods with or without a prebiotic to enhance colonic fermentation (10 g polyfructans/d), or 3) soy foods with a low-carbohydrate diet (26% carbohydrate). Studies 1 and 2 were randomized controlled crossover trials, and study 3 was a parallel study. RESULTS: The separation of the group into equol producers (n = 30) and nonproducers (n = 55) showed similar reductions from baseline in LDL cholesterol (-9.3 ± 2.5% and -11.1 ± 1.6%, respectively; P = 0.834), with preservation of HDL cholesterol and apolipoprotein A-I only in equol producers compared with reductions in nonproducers (HDL cholesterol: +0.9 ± 2.7% compared with -4.3 ± 1.1%, P = 0.006; apolipoprotein A-I: -1.0 ± 1.1% compared with -4.7 ± 1.0%; P = 0.011). The amount of urinary equol excreted did not relate to the changes in blood lipids. CONCLUSIONS: Soy foods reduced serum LDL cholesterol equally in both equol producers and nonproducers. However, in equol producers, ~35% of our study population, soy consumption had the added cardiovascular benefit of maintaining higher HDL-cholesterol concentrations than those seen in equol nonproducers. This trial was registered at clinicaltrials.gov as NCT00877825 (study 1), NCT00516594 (study 2), and NCT00256516 (study 3).


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Equol/sangue , Hiperlipidemias/sangue , Alimentos de Soja , Idoso , Apolipoproteína A-I/sangue , Doenças Cardiovasculares/prevenção & controle , Estudos Cross-Over , Dieta , Feminino , Humanos , Hiperlipidemias/dietoterapia , Hiperlipidemias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pós-Menopausa , Prebióticos/análise , Fatores de Risco
3.
Adv Ther ; 27(9): 634-47, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20721651

RESUMO

INTRODUCTION: Uremic syndrome consists of nitrogenous waste retention, deficiency in kidney-derived hormones, and reduced acid excretion, and, if untreated, may progress to coma and eventual death. Previous experience suggests that oral administration of a probiotic formulation of selected microbial strains may extend renoprotection via intraintestinal extraction of toxic waste solutes in patients with chronic kidney disease (CKD)stages 3 and 4. This report presents preliminary data from a pilot study. METHODS: This was a 6-month prospective, randomized, double-blind, placebo-controlled crossover trial of a probiotic bacterial formulation conducted in four countries, at five institutions, on 46 outpatients with CKD stages 3 an nd 4: USA (n=10), Canada (n=113), Nigeria (n=115), and Argentina (n=8). Outcomes were compared using biochemical parameters:blood urea nitrogen (BUN), serum creatinine, and uric acid. General well-being was assessed as a secondary parameter by a quality of life (QQOL) questionnaire on a subjective scale of 1-10. RESULTS: Oral ingestion of probiotics (90 billion colony forming units [CFUs]/day) was well tolerated and safe during the entire trial period at all sites. BUN levels decreased in 29 patients (63%, P<0.05), creatinine levels decreased in 20 patients (43%, no statistical significance), and uric acid levels decreased in 15 patients (33%, no statistical significance). Almost all subjects expressed a perceived substantial overall improvement in QOL (86%, P<0.05). CONCLUSION: The main outcomes of this preliminary trial include a significant reduction of BUN, enhanced well-being, and absence of serious adverse effects, thus supporting the use of the chosen probiotic formulation for bowel-based toxic solute extraction. QOL and BUN levels showed statistically significant differences in outcome (P<0.05) between placebo and probiotic treatment periods at all four sites (46 patients). A major limitation of this trial is the small sample size nd elated inconsistencies.


Assuntos
Probióticos , Insuficiência Renal Crônica/terapia , Uremia/prevenção & controle , Adulto , Idoso , Argentina , Canadá , Creatinina/análise , Suplementos Nutricionais/normas , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Nigéria , Projetos Piloto , Probióticos/farmacocinética , Substâncias Protetoras/farmacocinética , Qualidade de Vida , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia , Autorrelato , Resultado do Tratamento , Estados Unidos , Uremia/sangue , Uremia/etiologia , Uremia/fisiopatologia , Ácido Úrico/análise , Adulto Jovem
4.
J Nutr ; 140(9): 1633-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20668250

RESUMO

High-protein diets have been advocated for weight loss and the treatment of diabetes. Yet animal protein sources are often high in saturated fat and cholesterol. Vegetable protein sources, by contrast, are low in saturated fat and without associated cholesterol. We have therefore assessed the effect on serum lipids of raising the protein intake by 5% using a cereal protein, barley protein, as part of a standard therapeutic diet. Twenty-three hypercholesterolemic men and postmenopausal women completed a randomized crossover study comparing a bread enriched with either barley protein or calcium caseinate [30 g protein, 8374 kJ (2000 kcal)] taken separately as two 1-mo treatment phases with a minimum 2-wk washout. Body weight and diet history were collected weekly during each treatment. Fasting blood samples were obtained at wk 0, 2, and 4. Palatability, satiety, and compliance were similar for both the barley protein- and casein-enriched breads, with no differences between the treatments in effects on serum LDL cholesterol or C-reactive protein, measures of oxidative stress, or blood pressure. Nevertheless, because no adverse effects were observed on cardiovascular risk factors, barley protein remains an additional option for raising the protein content of the diet.


Assuntos
Caseínas/farmacologia , Hordeum/química , Hipercolesterolemia/dietoterapia , Lipídeos/sangue , Proteínas de Plantas/farmacologia , Adulto , Idoso , Pão/análise , Caseínas/química , Estudos Cross-Over , Suplementos Nutricionais , Feminino , Humanos , Hipolipemiantes , Masculino , Pessoa de Meia-Idade , Proteínas de Plantas/química
5.
J Agric Food Chem ; 58(7): 3871-83, 2010 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-20178390

RESUMO

Dietary guidelines around the world recommend the increased consumption of fruits and vegetables as good sources of antioxidant phytochemicals for the prevention of chronic diseases. Red raspberries are a common and important fruit in the Western diet due to their content of essential nutrients and beneficial phytochemicals. Anthocyanins and ellagitannins are polyphenolic compounds and the major antioxidant phytochemicals present in raspberries. Whereas individual phytochemical constituents of raspberries have been studied for their biological activities, human intervention studies using whole berries are lacking in the literature. The nutritional and phytochemical compositions of red raspberries and their absorption, metabolism, and biological activity are reviewed. Finally, future directions of research are also identified.


Assuntos
Saúde , Extratos Vegetais/análise , Rosaceae/química , Antioxidantes/uso terapêutico , Doença Crônica/prevenção & controle , Alimentos Orgânicos/análise , Frutas/química , Humanos , Medicina Preventiva
6.
Clin Breast Cancer ; 8(6): 506-10, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19073505

RESUMO

BACKGROUND: Several functions have been attributed to the BRCA1 protein. A recent study suggests that BRCA1 is involved in the cellular antioxidant response by inducing the expression of genes involved in the antioxidant defense system and thus conferring resistance to oxidative stress. It is possible that individuals with a BRCA1 mutation might be susceptible to the effects of oxidative stress. The aim of this study was to evaluate whether women with a BRCA1 mutation exhibit increased indicators of oxidative stress. PATIENTS AND METHODS: We measured 3 markers of oxidative stress in vivo, the amounts of serum malondialdehyde and protein thiols, and 8-oxo-2'-deoxyguanosine (8-oxodG) levels in 25 unaffected BRCA1 mutation carriers and 25 noncarrier control subjects. RESULTS: There was no significant difference in serum malondialdehyde levels (P=.41), serum thiol levels (P=.85), or the number of 8-oxodG lesions (P=.49) in BRCA1 mutation carriers versus noncarriers. CONCLUSION: The results of this study suggest that the presence of a heterozygous BRCA1 mutation is not associated with increased levels of indicators of oxidative stress in serum or lymphocytes. Future studies are warranted to evaluate whether strategies aimed at minimizing oxidative stress might aid in the prevention of hereditary breast cancer.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Mutação , Estresse Oxidativo/genética , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , Neoplasias da Mama/metabolismo , DNA/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Feminino , Heterozigoto , Humanos , Peroxidação de Lipídeos , Malondialdeído/sangue , Pessoa de Meia-Idade , Oxirredução , Compostos de Sulfidrila/sangue , Compostos de Sulfidrila/metabolismo , Adulto Jovem
7.
J Diet Suppl ; 5(3): 264-82, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-22432462

RESUMO

BACKGROUND AND AIMS: Oxidative stress has been associated with osteoporosis. Greens+™ is a commercially available nutritional supplement containing antioxidative polyphenols. METHODS: To study the effects of greens+™ on differentiation and bone formation in human osteoblasts, the cells were cultured in Ham's F-12 medium in the absence or presence of varying concentrations of total free polyphenolic (TFP) in the extracts of greens+™. RESULTS: Our results showed that the number of osteoblasts increased (p <. 05) compared to vehicle control after 2 and 4 days of treatment but were reduced (p <. 05) after 7 days of treatment with 1.2-2.0 mg greens+™ extract/ml (corresponding to 16.8-27.9 ng TFP expressed as gallic acid equivalent per milliliter). Lower concentrations of greens+™ extract stimulated alkaline phosphatase activity at early time points (days 9 and 11), while higher concentrations at the later time point of day 13 resulted in a significant (p <. 05) inhibition, in a time (p <. 0001) and dose dependent (p <. 0001) manner. Greens+™ extract stimulated (p <. 05) the mineralized bone nodule formation in a dose and time dependent manner. CONCLUSIONS: The results showed that greens+™ extract influenced the maturation of osteoprogenitors toward progression to a bone-forming stage. Our data suggest that greens+™ may have beneficial effects on bone formation in vitro due to its antioxidant polyphenolic content and we can speculate that it may be a good alternative to drugs for the prevention of osteoporosis.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Suplementos Nutricionais , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Fosfatase Alcalina/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Osteoblastos/metabolismo , Osteoporose/etiologia , Osteoporose/metabolismo , Polifenóis/uso terapêutico
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