Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Food Sci Nutr ; 3(5): 376-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26405524

RESUMO

Moderate protein and nonfat dairy intake within an energy-reduced diet (ERD) may contribute to health benefits achieved with body weight (BW) loss. The current study examined the effectiveness of a weight-loss/weight-loss maintenance intervention using an ERD with moderate dietary protein (30% of kcals) and increased nonfat dairy intake (4-5 svg/d), including yogurt (INT group) and daily walking compared to an ERD with standard protein (16-17% of kcals) and standard nonfat dairy intake (3 svg/d) (COM group) with daily walking. A randomized comparative trial with 104 healthy premenopausal women with overweight/obesity was conducted in a university setting. Women were randomized to INT group or COM group. Anthropometric measurements, as well as dietary intake, selected vital signs, resting energy expenditure, blood lipids, glucose, insulin, and selected adipose-derived hormones were measured at baseline, and weeks 2, 12, and 24. Targets for dietary protein and nonfat dairy intake, while initially achieved, were not sustained in the INT group. There were no significant effects of diet group on anthropometric measurements. Women in the INT group and COM group, respectively, reduced BW (-4.9 ± 3.2 and -4.3 ± 3.3 kg, P < 0.001) and fat mass (-3.0 ± 2.2 and -2.3 ± 2.3 kg, P < 0.001) during the 12-week weight-loss phase and maintained these losses at 24 weeks. Both groups experienced significant decreases in body mass index, fat-free soft tissue mass, body fat percentage, waist and hip circumferences and serum triglycerides, total cholesterol, and leptin (all P < 0.001). Healthy premenopausal women with excess adiposity effectively lost BW and fat mass and improved some metabolic risk factors following an ERD with approximately 20% protein and 3 svg/d of nonfat dairy intake.

2.
J Food Sci ; 77(4): H88-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22394255

RESUMO

UNLABELLED: Age-related changes in calcium metabolism play a role in the development of osteoporosis. A 4-wk feeding study was conducted in 5-mo-old ovariectomized (OVX) Sprague-Dawley rats to assess the effect of various dietary fibers on mineral metabolism and bone health parameters. There were 6 treatment groups: sham-Control, OVX-Control, OVX rats receiving daily estradiol (E2) injections, and OVX rats receiving an AIN-93M diet supplement with either an inulin-based fiber (Synergy1® or Fruitafit HD®) or a novel fiber (polydextrose) at 5% wt. of diet. Calcium and magnesium metabolic balances were performed after early (3 d) and late exposure (4 wk) to dietary treatments. Rats receiving polydextrose had significantly higher net calcium absorption efficiency and retention than all control groups and a trend (P≤ 0.10) for higher calcium absorption when compared to inulin-based fibers after early exposure but the advantage did not persist over long-term exposure. The inulin-based fibers had positive chronic effects on calcium metabolism that were related to changes in the gut, that is, production of short chain fatty acids and higher cecal wall weights. All fibers improved magnesium absorption and retention in early and late metabolic balances; effects on magnesium metabolism were more pronounced than for calcium. PRACTICAL APPLICATION: Steady growth in US middle-aged and elderly populations has led to higher incidences of several chronic diseases including osteoporosis, a bone disease that primarily affects postmenopausal women. Recent research suggests that certain dietary fibers (prebiotics) enhance mineral absorption and may impart bone health benefits. This work examines the impact of prebiotic supplementation on mineral metabolism and bone health using a postmenopausal rat model. Study findings will aid future investigations in ascertaining the factors related to potential bone health benefits of prebiotic which will aid in developing an effective prebiotics food product/supplement that will address the bone health needs of consumers.


Assuntos
Cálcio/metabolismo , Modelos Animais de Doenças , Absorção Intestinal , Inulina/uso terapêutico , Magnésio/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Prebióticos , Animais , Densidade Óssea , Osso e Ossos/metabolismo , Ceco/metabolismo , Ceco/patologia , Ácidos Graxos Voláteis/metabolismo , Feminino , Conteúdo Gastrointestinal/química , Glucanos/química , Glucanos/uso terapêutico , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Inulina/química , Cinética , Oligossacarídeos/química , Oligossacarídeos/uso terapêutico , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/patologia , Ratos , Ratos Sprague-Dawley , Solubilidade
3.
J Am Diet Assoc ; 111(6): 828-43, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21616195

RESUMO

BACKGROUND: A number of diet and exercise programs purport to help promote and maintain weight loss. However, few studies have compared the efficacy of different methods. OBJECTIVE: To determine whether adherence to a meal-replacement-based diet program (MRP) with encouragement to increase physical activity is as effective as following a more structured meal-plan-based diet and supervised exercise program (SDE) in sedentary obese women. DESIGN: Randomized comparative effectiveness trial. PARTICIPANTS/SETTING: From July 2007 to October 2008, 90 obese and apparently healthy women completed a 10-week university-based weight loss trial while 77 women from this cohort also completed a 24-week weight maintenance phase. INTERVENTION: Participants were matched and randomized to participate in an MRP or SDE program. MAIN OUTCOME MEASURES: Weight loss, health, and fitness-related data were assessed at 0 and 10 weeks on all subjects as well as at 14, 22, and 34 weeks on participants who completed the weight maintenance phase. STATISTICAL ANALYSES PERFORMED: Data were analyzed by multivariate analysis of variance for repeated measures. RESULTS: During the 10-week weight loss phase, moderate and vigorous physical activity levels were significantly higher in the SDE group with no differences observed between groups in daily energy intake. The SDE group lost more weight (-3.1 ± 3.7 vs -1.6 ± 2.5 kg; P = 0.03); fat mass (-2.3 ± 3.5 vs -0.9 ± 1.6 kg; P = 0.02); centimeters from the hips (-4.6 ± 7 vs -0.2 ± 6 cm; P = 0.002) and waist (-2.9 ± 6 vs -0.6 ± 5 cm; P = 0.05); and, experienced a greater increase in peak aerobic capacity than participants in the MRP group. During the 24-week maintenance phase, participants in the SDE group maintained greater moderate and vigorous physical activity levels, weight loss, fat loss, and saw greater improvement in maximal aerobic capacity and strength. CONCLUSIONS: In sedentary and obese women, an SDE-based program appears to be more efficacious in promoting and maintaining weight loss and improvements in markers of health and fitness compared to an MRP type program with encouragement to increase physical activity.


Assuntos
Dieta/normas , Exercício Físico/fisiologia , Alimentos Formulados , Promoção da Saúde/métodos , Obesidade/terapia , Redução de Peso , Adulto , Metabolismo Basal/fisiologia , Composição Corporal/fisiologia , Metabolismo Energético/fisiologia , Feminino , Frequência Cardíaca , Humanos , Metabolismo dos Lipídeos/fisiologia , Análise Multivariada , Obesidade/sangue , Consumo de Oxigênio , Cooperação do Paciente , Avaliação de Programas e Projetos de Saúde , Comportamento Sedentário , Resultado do Tratamento
4.
J Agric Food Chem ; 58(18): 9979-87, 2010 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-20731353

RESUMO

Isotopically labeled tomato carotenoids, phytoene, phytofluene, and lycopene, are needed for mammalian bioavailability and metabolism research but are currently commercially unavailable. The goals of this work were to establish and screen multiple in vitro tomato cell lines for carotenoid production, test the best producers with or without the bleaching herbicides, norflurazon and 2-(4-chlorophenyl-thio)triethylamine (CPTA), and to use the greatest carotenoid accumulator for in vitro 13C-labeling. Different Solanum lycopersicum allelic variants for high lycopene and varying herbicide treatments were compared for carotenoid accumulation in callus and suspension culture, and cell suspension cultures of the hp-1 line were chosen for isotopic labeling. When grown with [U]-13C-glucose and treated with CPTA, hp-1 suspensions yielded highly enriched 13C-lycopene with 45% of lycopene in the M+40 form and 88% in the M+35 to M+40 isotopomer range. To the authors' knowledge this is the first report of highly enriched 13C-carotenoid production from in vitro plant cell culture.


Assuntos
Carotenoides/biossíntese , Marcação por Isótopo/métodos , Solanum lycopersicum/metabolismo , Isótopos de Carbono , Linhagem Celular , Solanum lycopersicum/citologia
5.
J Exp Biol ; 210(Pt 4): 561-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17267641

RESUMO

Computing the direction and amplitude of orienting and avoidance turns is fundamental to prey pursuit and risk avoidance in motile foragers. We examined computation of turns in the predatory sea-slug Pleurobranchaea californica, observing orienting and aversive turn responses to chemotactile stimuli applied to the chemosensory oral veil. We made seven observations: (1) the relation of turn angle/stimulus site on the oral veil was linear; (2) turn amplitudes increased with stimulus strength; (3) turn responses markedly overshot the target stimulus; (4) responses to two simultaneous stimuli at different loci were averaged to an intermediate angle; (5) stimuli could induce sequential turns in which the angles of the first and third turns were similar, a form of working memory; (6) turn direction was affected by appetitive state, so that animals with higher feeding thresholds tended to avoid appetitive stimuli; and (7) avoidance turns induced by mildly noxious stimuli were computed similarly to orienting, while differing in direction. These observations appear to outline a framework of behavior that could be employed for efficient tracking of odor trails, and which is regulated by decision mechanisms that integrate sensation, internal state and experience.


Assuntos
Quimiotaxia/fisiologia , Reação de Fuga/fisiologia , Locomoção/fisiologia , Orientação/fisiologia , Pleurobranchaea/fisiologia , Animais , Estimulação Química
6.
Nutr Res ; 27(12): 794-801, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19050742

RESUMO

Tomato product consumption is inversely related to prostate cancer incidence, and lycopene (LYC) has been implicated in reduced prostate cancer risk. The contribution of other tomato carotenoids, phytoene (PE) and phytofluene (PF), towards prostate cancer risk has not been adequately studied. The relative uptake and tissue distribution of tomato carotenoids are not known. We hypothesize that PE and PF are bioavailable from a tomato powder diet or from a purified source and accumulate in androgen-sensitive tissues. In this study, 4 wk old male Fisher 344 rats were pre-fed an AIN-93G powder diet composed of 10% tomato powder containing PE, PF, and LYC (0.015, 0.012, and 0.011 g/kg diet, respectively). After 30 d tomato powder feeding, hepatic PF concentrations (168 ± 20 nmol/g) were higher than PE or LYC (104 ± 13 and 104 ± 13 nmol/g, respectively). In contrast, LYC, followed by PF, had the highest accumulation of the measured carotenoids in the prostate lobes and seminal vesicles. When tomato powder-fed rats received a single oral dose of either ∼2.7 mg PE or PF, an increase in the dosed carotenoid concentration was observed in all measured tissues, except the adrenal. Percent increases of PF were greater than that of PE in liver, serum, and adipose (37, 287 and 49% versus 16, 179 and 23%, respectively). Results indicate that the relative tomato carotenoid biodistribution differs in liver and androgen-sensitive tissues, suggesting that minor changes in the number of sequential double bonds in carotenoid structures alter absorption and/or metabolism of tomato carotenoids.

7.
J Nutr ; 136(11): 2813-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17056806

RESUMO

Elevated serum androgens are associated with increased prostate cancer risk. Tomato consumption is also associated with reduced prostate cancer incidence, and the primary tomato carotenoid, lycopene, may modulate androgen activation in the prostate, yet little is known about other tomato carotenoids. To evaluate interrelations between phytofluene, lycopene, or tomato powder consumption and androgen status, 8-wk-old male F344 rats (fed a control AIN 93G diet) were castrated or sham-operated and subsequently provided with daily oral supplementation of phytofluene or lycopene ( approximately 0.7 mg/d) or fed a 10% tomato powder supplemented diet (AIN 93G) for 4 d. Sham-operated rats provided with either phytofluene, lycopene, or tomato powder had approximately 40-50% lower serum testosterone concentrations than the sham-operated, control-fed group. Tissue and serum phytofluene and lycopene concentrations were greater in castrated rats than in sham-operated rats, which may have been due in part to a decrease of hepatic CYP 3A1 mRNA expression and benzyloxyresorufin-O-dealkylase activity. Some changes in prostatic and testicular steroidogenic enzyme mRNA expression were found; in particular, prostate 17 beta-hydroxysteroid dehydrogenase 4 mRNA expression in castrated rats fed lycopene or tomato powder was 1.7-fold that of the sham-operated, control-fed group. Modest changes in mRNA expression of steroidogenic enzymes with short-term carotenoid intake may alter the flux of androgen synthesis to less potent compounds. Overall, results illustrate that short-term intake of tomato carotenoids significantly alters androgen status, which may partially be a mechanism by which tomato intake reduces prostate cancer risk.


Assuntos
Carotenoides/administração & dosagem , Solanum lycopersicum , Testosterona/sangue , 17-Hidroxiesteroide Desidrogenases/genética , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Carotenoides/farmacocinética , Citocromo P-450 CYP2B1/metabolismo , Citocromo P-450 CYP3A , Di-Hidrotestosterona/sangue , Proteína 3 Ligante de Ácido Graxo , Proteínas de Ligação a Ácido Graxo/genética , Licopeno , Masculino , PPAR gama/genética , Próstata/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Testículo/metabolismo
8.
J Agric Food Chem ; 54(3): 747-55, 2006 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-16448178

RESUMO

This work describes the development and utilization of a plant cell culture production approach to biosynthesize and radiolabel phytoene and phytofluene for prostate cancer cell culture studies. The herbicide norflurazon was added to established cell suspension cultures of tomato (Lycopersicon esculentum cv. VFNT cherry), to induce the biosynthesis and accumulation of the lycopene precursors, phytoene and phytofluene, in their natural isomeric forms (15-cis-phytoene and two cis-phytofluene isomers). Norflurazon concentrations, solvent carrier type and concentration, and duration of culture exposure to norflurazon were screened to optimize phytoene and phytofluene synthesis. Maximum yields of both phytoene and phytofluene were achieved after 7 days of treatment with 0.03 mg norflurazon/40 mL fresh medium, provided in 0.07% solvent carrier. Introduction of 14C-sucrose to the tomato cell culture medium enabled the production of 14C-labeled phytoene for subsequent prostate tumor cell uptake studies. In DU 145 prostate tumor cells, it was determined that 15-cis-phytoene and an oxidized product of phytoene were taken up and partially metabolized by the cells. The ability to biosynthesize, radiolabel, and isolate these carotenoids from tomato cell cultures is a novel, valuable methodology for further in vitro and in vivo investigations into the roles of phytoene and phytofluene in cancer chemoprevention.


Assuntos
Carotenoides/biossíntese , Marcação por Isótopo/métodos , Neoplasias da Próstata/metabolismo , Solanum lycopersicum/metabolismo , Adenocarcinoma/metabolismo , Radioisótopos de Carbono , Carotenoides/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Masculino
9.
J Nutr ; 135(5): 1226-30, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15867308

RESUMO

Tomatoes are the fourth most commonly consumed fresh vegetable and the most frequently consumed canned vegetable in the American diet. There is emerging epidemiology data supporting the connection between increased tomato consumption and reduced risk for both cardiovascular disease and prostate cancer. Here we will summarize the nutrient and the phytochemical content of tomatoes and tomato products, and how these bioactive components might act together to modulate disease development. Recent animal studies have investigated tomatoes, lycopene, and prostate cancer using the N-methyl-N-nitrosourea and Dunning rat models. These animal studies also suggest that diets containing tomatoes may decrease the risk or the progression of prostate cancer. Due to the frequency and the extent of tomato consumption, the supporting epidemiological and animal data, which connect increased intakes with decreased cancer and cardiovascular disease risk, tomato's role in the American diet is of undeniable importance as part of a healthy diet.


Assuntos
Alimentos , Solanum lycopersicum , Carotenoides , Culinária , Doença das Coronárias/epidemiologia , Doença das Coronárias/prevenção & controle , Manipulação de Alimentos , Humanos , Licopeno , Masculino , Neoplasias da Próstata/prevenção & controle
10.
J Nutr ; 134(12 Suppl): 3486S-3492S, 2004 12.
Artigo em Inglês | MEDLINE | ID: mdl-15570058

RESUMO

Mounting evidence over the past decade suggests that the consumption of fresh and processed tomato products is associated with reduced risk of prostate cancer. The emerging hypothesis is that lycopene, the primary red carotenoid in tomatoes, may be the principle phytochemical responsible for this reduction in risk. A number of potential mechanisms by which lycopene may act have emerged, including serving as an important in vivo antioxidant, enhancing cell-to-cell communication via increasing gap junctions between cells, and modulating cell-cycle progression. Although the effect of lycopene is biologically relevant, the tomato is also an excellent source of nutrients, including folate, vitamin C, and various other carotenoids and phytochemicals, such as polyphenols, which also may be associated with lower cancer risk. Tomatoes also contain significant quantities of potassium, as well as some vitamin A and vitamin E. Our laboratory has been interested in identifying specific components or combination of components in tomatoes that are responsible for reducing prostate cancer risk. We carried out cell culture trials to evaluate the effects of tomato carotenoids and tomato polyphenols on growth of prostate cancer cells. We also evaluated the ability of freeze-dried whole-tomato powder or lycopene alone to reduce growth of prostate tumors in rats. This paper reviews the epidemiological evidence, evaluating the relationship between prostate cancer risk and tomato consumption, and presents experimental data from this and other laboratories that support the hypothesis that whole tomato and its phytochemical components reduce the risk of prostate cancer.


Assuntos
Neoplasias da Próstata/prevenção & controle , Solanum lycopersicum/química , Animais , Antioxidantes/administração & dosagem , Carotenoides/administração & dosagem , Carotenoides/sangue , Carotenoides/farmacologia , Comunicação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ensaios Clínicos como Assunto , Dieta , Flavonoides/farmacologia , Humanos , Licopeno , Masculino , Transplante de Neoplasias , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/prevenção & controle , Fenóis/farmacologia , Polifenóis , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...