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1.
Appetite ; 168: 105802, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34774669

RESUMO

Dietary fiber has numerous health benefits, such as increasing satiety, and is regularly included in healthy dietary recommendations. However, different types and sources of fiber vary in their chemical properties and biological effects. This double-blind, randomized, placebo-controlled, crossover study investigated the effects of resistant starch type 2 (RS2) from wheat on self-reported perceptions of satiety and associated gut hormones in 30 healthy adults ages 40-65 years of age. Participants consumed rolls made using either RS2-enriched wheat flour or a wild-type flour for one week before a test day during which they ate a mixed meal containing the same roll type. Both self-reported perceptions of satiety and plasma concentrations of gut hormones were measured following the meal to assess whether the RS2-enriched wheat enhanced satiety and suppressed hunger for a longer period than the control wheat. Exploratory analysis indicated that fasting and peak concentration of peptide YY3-36 (PYY3-36; qfast = 0.02, qpeak = 0.02) increased, while peak concentration and iAUC of glucose-dependent insulinotropic peptide (GIP; qpeak < 0.001, qiAUC < 0.001) decreased after ingesting RS2-enriched wheat. However, self-reported perceptions of hunger or fullness using visual analog scales (VAS) did not differ following the test meal.


Assuntos
Amido Resistente , Triticum , Adulto , Idoso , Glicemia , Estudos Cross-Over , Farinha , Humanos , Pessoa de Meia-Idade , Peptídeo YY , Período Pós-Prandial , Autorrelato
2.
J Nutr ; 151(6): 1443-1452, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33704458

RESUMO

BACKGROUND: Prior studies of adults with constipation or diarrhea suggest that dietary intake, physical activity, and stress may affect stool consistency. However, the influence of these factors is unresolved and has not been investigated in healthy adults. OBJECTIVES: We assessed the relations of technician-scored stool consistency in healthy adults with self-reported diet, objectively monitored physical activity, and quantifiable markers of stress. METHODS: Stool consistency was scored by an independent technician using the Bristol Stool Form Scale (BSFS) to analyze samples provided by healthy adults, aged 18-65 y, BMI 18-44 kg/m2, in the USDA Nutritional Phenotyping Study (n = 364). A subset of participants (n = 109) were also asked to rate their sample using the BSFS. Dietary intake was assessed with two to three 24-h recalls completed at home and energy expenditure from physical activity was monitored using an accelerometer in the 7-d period preceding the stool collection. Stress was measured using the Wheaton Chronic Stress Inventory and allostatic load (AL). Statistical and machine learning analyses were conducted to determine which dietary, physiological, lifestyle, and stress factors differed by stool form. RESULTS: Technician-scored BSFS scores were significantly further (P = 0.003) from the central score (mean ± SEM distance: 1.41 ± 0.089) than the self-reported score (1.06 ± 0.086). Hard stool was associated with higher (P = 0.005) intake of saturated fat (13.8 ± 0.40 g/1000 kcal) than was normal stool (12.5 ± 0.30 g/1000 kcal). AL scores were lower for normal stool (2.49 ± 0.15) than for hard (3.07 ± 0.18) (P = 0.009) or soft stool (2.89 ± 0.18) (P = 0.049). Machine learning analyses revealed that various dietary components, physiological characteristics, and stress hormones predicted stool consistency. CONCLUSIONS: Technician-scored stool consistency differed by dietary intake and stress hormones, but not by physical activity, in healthy adults.This trial was registered at clincialtrials.gov as NCT02367287.


Assuntos
Dieta , Fezes , Estresse Psicológico/epidemiologia , Adulto , Constipação Intestinal , Estudos Transversais , Diarreia , Exercício Físico , Hormônios , Humanos , Aprendizado de Máquina , Estados Unidos
3.
J Nutr ; 151(1): 245-254, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33245130

RESUMO

BACKGROUND: Inclusion of dairy in diet patterns has been shown to have mixed effects on weight loss. A prevailing hypothesis is that dairy improves weight loss by influencing endocrine systems associated with satiety and food intake regulation. OBJECTIVES: The objective of the current study was to evaluate the effect of weight loss with or without adequate dietary dairy on subjective and objective appetitive measures. METHODS: Men and women who were habitual low dairy consumers (n = 65, 20-50 y) participated in a 12-wk randomized controlled feeding weight loss trial. During the 12-wk intervention, a low-dairy (<1 serving dairy/d) was compared with an adequate-dairy (3-4 servings dairy/d) diet, both with a 500-kcal deficit/d. Test days, before and at the end of the intervention, began with 2 fasting blood draws and visual analog scale (VAS) measures, followed by a standard breakfast (25% of prescribed restricted calories), 5 postbreakfast blood draws and VASs, a standard lunch (40% of restricted energy amount), and 12 postlunch blood draws and VASs. Blood samples were used for satiety hormone measurements. On a separate day when matching standard meals were consumed, an ad libitum buffet meal was provided as dinner, at a self-selected time. Meal duration and intermeal interval were recorded. RESULTS: Weight loss (-6.1 kg), irrespective of dairy, resulted in reduced fasting insulin (-20%) and leptin (-25%), and increased fasting acylated ghrelin (+25%) and VAS desire to eat (+18%) (P < 0.05). There were no effects of dairy on objective or subjective satiety measures. Weight loss marginally reduced the intermeal interval (289 min compared with 276 min, P = 0.059) between lunch and the ad libitum buffet. CONCLUSIONS: These results do not support the hypothesis that inclusion of dairy in long-term dietary patterns influences appetite during weight loss. Weight loss per se has a modest impact on select systems that regulate hunger and satiety.This trial was registered at clinicaltrials.gov as NCT00858312.


Assuntos
Laticínios , Dieta , Trato Gastrointestinal/metabolismo , Período Pós-Prandial , Resposta de Saciedade , Redução de Peso , Adulto , Feminino , Grelina/metabolismo , Humanos , Insulina/metabolismo , Leptina/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Clin Infect Dis ; 66(2): 220-228, 2018 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-29020329

RESUMO

Background: Tenofovir disoproxil fumarate (TDF) decreases bone mineral density (BMD). We hypothesized that vitamin D3 (VITD3) would increase BMD in youth receiving TDF. Methods: This was a randomized, double-blind, placebo-controlled trial of directly observed VITD3 vs placebo every 4 weeks for 48 weeks in youth aged 16-24 years with HIV, RNA load <200 copies/mL, taking TDF-containing combination antiretroviral therapy (TDF-cART) for ≥180 days. Participants (N = 214) received a daily multivitamin containing VITD3 400 IU and calcium 162 mg, plus monthly randomized VITD3 50000 IU (n = 109) or placebo (n = 105). Outcome was change from baseline to week 48 in lumbar spine BMD (LSBMD). Data presented are median (Q1, Q3). Results: Participants were aged 22.0 (21.0, 23.0) years, 84% were male, and 74% were black/African American. At baseline, 62% had 25-hydroxy vitamin D (25-OHD) <20 ng/mL. Multivitamin adherence was 49% (29%, 69%), and VITD3/placebo adherence 100% (100%, 100%). Vitamin D intake was 2020 (1914, 2168) and 284 (179, 394) IU/day, and serum 25-OHD concentration was 36.9 (30.5, 42.4) and 20.6 (14.4, 25.8) ng/mL at 48 weeks in VITD3 and placebo groups, respectively (P < .001). From baseline to week 48, LSBMD increased by 1.15% (-0.75% to 2.74%) in the VITD3 group (n = 99; P < .001) and 0.09% (-1.49% to 2.61%) in the placebo group (n = 89; P = .25), without between-group difference (P = .12). VITD3 group changes occurred with baseline 25-OHD <20 ng/mL (1.17% [-.82% to 2.90%]; P = .004) and ≥20 ng/mL (0.93% [-.26% to 2.15%]; P = .033). Conclusions: For youth taking TDF-cART, LSBMD increased through 48 weeks with VITD3 plus multivitamin, but not with placebo plus multivitamin, independent of baseline vitamin D status. Clinical Trials Registration: NCT01751646.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Colecalciferol/administração & dosagem , Infecções por HIV/tratamento farmacológico , Coluna Vertebral/fisiologia , Tenofovir/administração & dosagem , Adolescente , Hormônios e Agentes Reguladores de Cálcio , Método Duplo-Cego , Feminino , Humanos , Masculino , Placebos/administração & dosagem , Resultado do Tratamento , Adulto Jovem
5.
Clin Infect Dis ; 64(3): 317-325, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28013265

RESUMO

BACKGROUND: We aimed to define the relative importance of renal and endocrine changes in tenofovir disoproxil fumarate (TDF)-related bone toxicity. METHODS: In a study of daily TDF/emtricitabine (FTC) preexposure prophylaxis (PrEP) in human immunodeficiency virus (HIV)-uninfected young men who have sex with men, we measured changes from baseline in blood and urine markers of the parathyroid hormone (PTH)-vitamin D-fibroblast growth factor 23 (FGF23) axis, creatinine, and renal tubular reabsorption of phosphate (TRP). We explored the relationship of those variables to changes in bone mineral density (BMD). Tenofovir-diphosphate (TFV-DP) in red blood cells was used to categorize participants into high and low drug exposure groups. RESULTS: There were 101 participants, median age 20 years (range 15 to 22). Compared with low drug exposure, high-exposure participants showed increase from baseline in PTH and decline in FGF23 by study week 4, with no differences in creatinine, phosphate, or TRP. At 48 weeks, the median (interquartile range) percent decline in total hip BMD was greater in those with high- compared to low- exposure (-1.59 [2.77] vs +1.54 [3.34] %, respectively; P = .001); in high-exposure participants, this correlated with week 4 TFV-DP (inversely; r = -0.60, P = .002) and FGF23 (directly; r = 0.42; P = .039) but not other variables. CONCLUSIONS: These findings support the short-term renal safety of TDF/FTC PrEP in HIV-seronegative young men and suggest that endocrine disruption (PTH-FGF23) is a primary contributor to TDF-associated BMD decline in this age group. CLINICAL TRIALS REGISTRATION: NCT01769469.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Emtricitabina/efeitos adversos , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Profilaxia Pré-Exposição , Tenofovir/efeitos adversos , Adolescente , Fármacos Anti-HIV/administração & dosagem , Creatinina/sangue , Creatinina/urina , Emtricitabina/administração & dosagem , Fator de Crescimento de Fibroblastos 23 , Taxa de Filtração Glomerular/efeitos dos fármacos , Infecções por HIV/sangue , Infecções por HIV/metabolismo , Infecções por HIV/urina , Humanos , Rim/efeitos dos fármacos , Masculino , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/urina , Insuficiência Renal/induzido quimicamente , Tenofovir/administração & dosagem , Adulto Jovem
6.
J Nutr ; 146(7): 1411-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27306892

RESUMO

BACKGROUND: Saturated fatty acids (FAs) released from triglyceride-rich lipoproteins (TGRLs) activate Toll-like receptor 2 (TLR-2) and induce the expression of proinflammatory cytokines in monocytes. Certain plant polyphenols inhibit TLR-mediated signaling pathways. OBJECTIVE: We determined whether plasma free FAs (FFAs) after a moderately high-fat (MHF, 40% kcal from fat) breakfast modulate the inflammatory status of postprandial blood, and whether blueberry intake suppresses FFA-induced inflammatory responses in healthy humans. METHODS: Twenty-three volunteers with a mean ± SEM age and body mass index (in kg/m(2)) of 30 ± 3 y and 21.9 ± 0.4, respectively, consumed an MHF breakfast with either a placebo powder or 2 or 4 servings of blueberry powder in a randomized crossover design. The placebo powder was provided on the first test day and the blueberry powder doses were randomized with a 2-wk washout period. Plasma concentrations of lipids, glucose, and cytokines were determined. To determine whether FFAs derived from TGRL stimulate monocyte activation, and whether this is inhibited by blueberry intake, whole blood was treated with lipoprotein lipase (LPL). RESULTS: The median concentrations of FFAs and cytokines [tumor necrosis factor-α, interleukin (IL)-6 and IL-8] in postprandial plasma (3.5 h) decreased compared with fasting plasma regardless of the blueberry intake (P < 0.001 for FFAs and P < 0.05 for cytokines). However, concentrations of FFAs and cytokines including IL-1ß increased in LPL-treated whole blood compared with untreated blood samples from participants who consumed the placebo powder. Blueberry intake suppressed IL-1ß and IL-6 production in LPL-treated postprandial blood compared with the placebo control when fasting changes were used as a covariate. CONCLUSIONS: The plasma FFA concentration may be an important determinant affecting inflammatory cytokine production in blood. Supplementation with blueberry powder did not affect plasma FFA and cytokine concentrations; however, it attenuated the cytokine production induced by ex vivo treatment of whole blood with LPL. This trial was registered at clinicaltrials.gov as NCT01594008.


Assuntos
Mirtilos Azuis (Planta) , Gorduras na Dieta , Ácidos Graxos não Esterificados/sangue , Inflamação/sangue , Refeições , Período Pós-Prandial , Adulto , Estudos Cross-Over , Citocinas/sangue , Citocinas/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/prevenção & controle , Monócitos/efeitos dos fármacos , Monócitos/fisiologia , Pós
7.
Br J Nutr ; 112(3): 369-80, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24832727

RESUMO

Obese individuals are at an increased risk of developing CVD, hypertension, type 2 diabetes, and bacterial and viral infections when compared with the normal-weight population. In a 9-week randomised, double-blind, cross-over study, twenty-four obese subjects aged between 20 and 60 years and with a BMI between 30 and 45 kg/m2 were fed grape or placebo powder for 3-week intervals to determine the effects of dietary grapes on blood lipid profiles, plasma inflammatory marker concentrations and immune cell function. Blood samples were collected on days 1 and 8 for obtaining baseline information and at weeks 3, 4, 8 and 9. Comprehensive chemistry panels, lipid profile analyses by NMR, measurement of plasma inflammatory marker concentrations, and analyses of cytokine production by activated T lymphocytes and monocytes were performed for each blood draw. Dietary grape powder reduced the plasma concentrations of large LDL-cholesterol and large LDL particles compared with the placebo powder (P< 0·05). The concentrations of interferon-γ, TNF-α, IL-4 and IL-10 were measured in supernatants from peripheral blood mononuclear cells (PBMC) activated with anti-CD3/CD28 antibodies and those of TNF-α, IL-1ß, IL-6 and IL-8 were measured in supernatants from PBMC activated with lipopolysaccharide (LPS). No difference in the production of T-cell cytokines was observed between the two intervention groups. The production of IL-1ß and IL-6 was increased in supernatants from LPS-activated PBMC in the grape powder group compared with the placebo powder group (P< 0·05). These data suggest that dietary grapes may decrease atherogenic lipid fractions in obese individuals and increase the sensitivity of monocytes in a population at a greater risk of developing infections.


Assuntos
Dieta , Interleucinas/biossíntese , Lipoproteínas LDL/sangue , Monócitos/metabolismo , Obesidade/sangue , Vitis , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , LDL-Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Frutas/química , Humanos , Inflamação/sangue , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/imunologia , Tamanho da Partícula , Placebos , Polifenóis/análise , Polifenóis/farmacocinética , Zinco/sangue
8.
Antimicrob Agents Chemother ; 57(11): 5619-28, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24002093

RESUMO

Tenofovir disoproxil fumarate (TDF) causes bone, endocrine, and renal changes by an unknown mechanism(s). Data are limited on tenofovir pharmacokinetics and these effects. Using baseline data from a multicenter study of HIV-infected youth on stable treatment with regimens containing TDF (n = 118) or lacking TDF (n = 85), we measured cross-sectional associations of TDF use with markers of renal function, vitamin D-calcium-parathyroid hormone balance, phosphate metabolism (tubular reabsorption of phosphate and fibroblast growth factor 23 [FGF23]), and bone turnover. Pharmacokinetic-pharmacodynamic associations with plasma tenofovir and intracellular tenofovir diphosphate concentrations were explored among those receiving TDF. The mean age was 20.9 (standard deviation [SD], 2.0) years; 63% were male; and 52% were African American. Compared to the no-TDF group, the TDF group showed lower mean estimated glomerular filtration rates and tubular reabsorption of phosphate, as well as higher parathyroid hormone and 1,25-dihydroxy vitamin D [1,25-OH(2)D] levels. The highest quintile of plasma tenofovir concentrations was associated with higher vitamin D binding protein, lower free 1,25-OH(2)D, higher 25-OH vitamin D, and higher serum calcium. The highest quintile of intracellular tenofovir diphosphate concentration was associated with lower FGF23. Higher plasma tenofovir concentrations were associated with higher vitamin D binding protein and lower free 1,25-OH(2)D, suggesting a functional vitamin D deficiency explaining TDF-associated increased parathyroid hormone. The finding of lower FGF23 accompanying higher intracellular tenofovir diphosphate suggests that different mechanisms mediate TDF-associated changes in phosphate handling. Separate pharmacokinetic properties may be associated with distinct TDF toxicities: tenofovir with parathyroid hormone and altered calcium balance and tenofovir diphosphate with hypophosphatemia and FGF23 regulation. (The clinical trial registration number for this study is NCT00490412 and is available online at http://clinicaltrials.gov/ct2/show/NCT00490412.).


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/farmacocinética , Calcitriol/sangue , Infecções por HIV/sangue , Hipofosfatemia/sangue , Organofosfonatos/farmacocinética , Inibidores da Transcriptase Reversa/farmacocinética , Deficiência de Vitamina D/sangue , Adenina/efeitos adversos , Adenina/sangue , Adenina/farmacocinética , Adolescente , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/sangue , Cálcio/sangue , Método Duplo-Cego , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Taxa de Filtração Glomerular , HIV/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Hipofosfatemia/induzido quimicamente , Hipofosfatemia/virologia , Masculino , Organofosfonatos/efeitos adversos , Organofosfonatos/sangue , Hormônio Paratireóideo/sangue , Fosfatos/sangue , Inibidores da Transcriptase Reversa/efeitos adversos , Inibidores da Transcriptase Reversa/sangue , Tenofovir , Deficiência de Vitamina D/induzido quimicamente , Deficiência de Vitamina D/virologia , Proteína de Ligação a Vitamina D/sangue
9.
J Nutr ; 143(3): 340-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23343675

RESUMO

A limited number of studies have demonstrated that some modulators of inflammation can be altered by the consumption of sweet cherries. We have taken a proteomics approach to determine the effects of dietary cherries on targeted gene expression. The purpose was then to determine changes caused by cherry consumption in the plasma concentrations of multiple biomarkers for several chronic inflammatory diseases in healthy humans with modestly elevated C-reactive protein (CRP; range, 1-14 mg/L; mean, 3.5 mg/L; normal, <1.0 mg/L). Eighteen men and women (45-61 y) supplemented their diets with Bing sweet cherries (280 g/d) for 28 d. Fasting blood samples were taken before the start of consuming the cherries (study d 7), 28 d after the initiation of cherry supplementation (d 35), and 28 d after the discontinuation (d 63). Of the 89 biomarkers assessed, cherry consumption for 28 d altered concentrations of 9, did not change those of 67, and the other 13 were below the detection limits. Cherry consumption decreased (P < 0.05) plasma concentrations of extracellular newly identified ligand for the receptor for advanced glycation end products (29.0%), CRP (20.1%), ferritin (20.3%), plasminogen activator inhibitor-1 (19.9%), endothelin-1 (13.7%), epidermal growth factor (13.2%), and IL-18 (8.1%) and increased that of IL-1 receptor antagonist (27.9%) compared with corresponding values on study d 7. The ferritin concentration continued to decrease between d 35 and 63 and it was significantly lower on d 63 than on d 7. Because the participants in this study were healthy, no clinical pathology end points were measured. However, results from the present study demonstrate that cherry consumption selectively reduced several biomarkers associated with inflammatory diseases.


Assuntos
Dieta , Frutas , Mediadores da Inflamação/sangue , Inflamação/prevenção & controle , Fitoterapia , Preparações de Plantas/uso terapêutico , Prunus , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doença Crônica , Suplementos Nutricionais , Endotelina-1/sangue , Fator de Crescimento Epidérmico/sangue , Feminino , Ferritinas/sangue , Humanos , Inflamação/sangue , Interleucina-18/sangue , Masculino , Pessoa de Meia-Idade , Preparações de Plantas/farmacologia , Inibidor 1 de Ativador de Plasminogênio/sangue , Proteômica , Receptores de Interleucina-1/sangue , Valores de Referência
10.
J Nutr ; 143(4): 519-25, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23427330

RESUMO

Information is needed on zinc absorption from grain cultivars having higher zinc content. Total absorbed zinc (TAZ) from mixed diets containing high-zinc rice (HZnR), conventional rice (CR), or CR plus zinc fortificant (CR+Zn) was measured. Forty-two nonmalnourished preschool-aged children were enrolled in 1 of 2 groups. Using a crossover design, children in group A (n = 22) received for 1 d each a mixed diet containing 150 g CR or HZnR. Children in group B (n = 20) received HZnR on 1 d and CR+Zn on the other day. Fractional zinc absorption (FZA) was measured during each dietary period by using a dual-isotope tracer ratio technique; TAZ was calculated as the product of zinc intake [total dietary zinc (TDZ)] and FZA. TDZ was 3.83, 4.83, and 6.03 mg/d when the children were fed the CR, HZnR, and CR+Zn-containing diets, respectively. Mean FZA from the CR diet was greater than from the HZnR diet (25.1 vs. 20.1%, P < 0.001), and the mean FZA from the CR+Zn diet (18.8%) was less than from both the CR diet (P < 0.001) and the HZnR diet (P = 0.014). The mean TAZ was 0.96 ± 0.16, 0.97 ± 0.18, and 1.13 ± 0.20 mg/d from the CR, HZnR and CR +Zn diets, respectively. TAZ was not different for the CR and HZnR diets (P = 0.99) but was significantly greater from the CR+Zn diet compared with the other 2 diets (P < 0.001). Rice cultivars with higher zinc and/or lower phytate content are needed to increase TAZ by young children consuming this amount of rice.


Assuntos
Alimentos Fortificados , Oryza/química , Zinco/farmacocinética , Bangladesh , Disponibilidade Biológica , Pré-Escolar , Estudos Cross-Over , Dieta , Feminino , Humanos , Masculino , Sementes/química , Zinco/administração & dosagem , Zinco/deficiência , Isótopos de Zinco/urina
11.
Br J Nutr ; 110(2): 310-20, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23332040

RESUMO

Biofortification of cassava with the provitamin A carotenoid ß-carotene is a potential mechanism for alleviating vitamin A deficiency. Cassava is a staple food in the African diet, but data regarding the human bioavailability of ß-carotene from this food are scarce. The objective of the present study was to evaluate provitamin A-enhanced cassava as a source of ß-carotene and vitamin A for healthy adult women. The study was a randomised, cross-over trial of ten American women. The subjects consumed three different porridges separated by 2 week washout periods. Treatment meals (containing 100 g cassava) included: biofortified cassava (2 mg ß-carotene) porridge with added oil (15 ml peanut or rapeseed oil, 20 g total fat); biofortified cassava porridge without added oil (6 g total fat); unfortified white cassava porridge with a 0·3 mg retinyl palmitate reference dose and added oil (20 g total fat). Blood was collected six times from - 0·5 to 9·5 h post-feeding. TAG-rich lipoprotein (TRL) plasma was separated by ultracentrifugation and analysed using HPLC with coulometric array electrochemical detection. The AUC for retinyl palmitate increased after the biofortified cassava meals were fed (P< 0·05). Vitamin A conversion was 4·2 (sd 3·1) and 4·5 (sd 3·1) µg ß-carotene:1 µg retinol, with and without added oil, respectively. These results show that biofortified cassava increases ß-carotene and retinyl palmitate TRL plasma concentrations in healthy well-nourished adult women, suggesting that it is a viable intervention food for preventing vitamin A deficiency.


Assuntos
Alimentos Fortificados , Lipoproteínas/sangue , Manihot/química , Triglicerídeos/sangue , Deficiência de Vitamina A/sangue , Vitamina A/análogos & derivados , beta Caroteno/farmacologia , Adulto , Área Sob a Curva , Diterpenos , Feminino , Humanos , Óleos de Plantas/farmacologia , Valores de Referência , Ésteres de Retinil , Vitamina A/sangue , Deficiência de Vitamina A/dietoterapia , Adulto Jovem
12.
Clin Infect Dis ; 54(7): 1013-25, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22267714

RESUMO

BACKGROUND: The study goal was to determine the effect of vitamin D (VITD) supplementation on tubular reabsorption of phosphate (TRP), parathyroid hormone (PTH), bone alkaline phosphatase (BAP), and C-telopeptide (CTX) in youth infected with human immunodeficiency virus (HIV) receiving and not receiving combination antiretroviral therapy (cART) containing tenofovir disoproxil fumarate (TDF). METHODS: This randomized, double-blind, placebo-controlled multicenter trial enrolled HIV-infected youth 18-25 years based on stable treatment with cART containing TDF (n = 118) or no TDF (noTDF; n = 85), and randomized within those groups to vitamin D3, 50 000 IU (n = 102) or placebo (n = 101), administered at 0, 4, and 8 weeks. Outcomes included change in TRP, PTH, BAP, and CTX from baseline to week 12 by TDF/noTDF; and VITD/placebo. RESULTS: At baseline, VITD and placebo groups were similar except those on TDF had lower TRP and higher PTH and CTX. At week 12, 95% in the VITD group had sufficient serum 25-hydroxy vitamin D (25-OHD; ≥20 ng/mL), increased from 48% at baseline, without change in placebo (P < .001). PTH decreased in the TDF group receiving VITD (P = .031) but not in the noTDF group receiving VITD, or either placebo group. The decrease in PTH with VITD in those on TDF occurred with insufficient and sufficient baseline 25-OHD (mean PTH change, -7.9 and -6.2 pg/mL; P = .031 and .053, respectively). CONCLUSIONS: In youth on TDF, vitamin D3 supplementation decreased PTH, regardless of baseline 25-OHD concentration. CLINICAL TRIALS REGISTRATION: NCT00490412.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/administração & dosagem , Colecalciferol/administração & dosagem , Infecções por HIV/tratamento farmacológico , Organofosfonatos/administração & dosagem , Hormônio Paratireóideo/sangue , Vitaminas/administração & dosagem , Adenina/administração & dosagem , Adolescente , Terapia Antirretroviral de Alta Atividade/métodos , Método Duplo-Cego , Interações Medicamentosas , Feminino , Humanos , Masculino , Estudos Multicêntricos como Assunto , Placebos/administração & dosagem , Tenofovir , Adulto Jovem
13.
Br J Nutr ; 108(5): 900-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22068016

RESUMO

Obesity is a strong risk factor for the development of CVD, hypertension and type 2 diabetes. The overall goal of the present pilot study was to feed strawberries, in the form of freeze-dried powder, to obese subjects to determine whether dietary strawberries beneficially altered lipid profiles and reduced blood markers of inflammation compared with a control intervention. A total of twenty healthy subjects (thirteen females and seven males) aged between 20 and 50 years with a BMI between 30 and 40 kg/m2 completed the present 7-week double-blind, randomised, cross-over trial. Each subject received a prepared diet 7 d/week for 7 weeks consisting of approximately 35 % of energy from fat, 20 % protein, 45 % carbohydrate and 14 g fibre. Blood was collected on days 1 and 8 for baseline information. After the first week, subjects were randomly assigned to the strawberry powder (equivalent to four servings of frozen strawberries) or control (strawberry-flavoured) intervention for 3 weeks. For the remaining 3 weeks, subjects crossed over to the opposite intervention. Blood was collected again at the end of weeks 3, 4, 6 and 7. A comprehensive chemistry panel, lipid profile analyses and measurement of inflammatory mediators were performed for each blood draw. A 3-week dietary intervention with strawberry powder reduced plasma concentrations of cholesterol and small HDL-cholesterol particles, and increased LDL particle size in obese subjects (P < 0·05). Dietary strawberry powder reduced risk factors for CVD, stroke and diabetes in obese volunteers, suggesting a potential role for strawberries as a dietary means to decrease obesity-related disease.


Assuntos
Biomarcadores/sangue , Dieta , Fragaria , Lipídeos/sangue , Obesidade/sangue , Adulto , Estudos Cross-Over , Método Duplo-Cego , Humanos , Inflamação , Masculino , Pós
14.
BMC Nutr ; 8(1): 157, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575541

RESUMO

OBJECTIVE: To evaluate the effect of a diet pattern based on Dietary Guidelines for Americans (DGA), in a controlled feeding setting, on plasma markers of inflammation and on cytokine production by peripheral blood mononuclear cells (PBMC). DESIGN: Women (n = 44) with one or more risk factors of metabolic syndrome (and BMI: 25.2-39.8 kg/m2) completed an 8-wk controlled feeding study. They were randomized to either a group following a diet based on DGA 2010 (DGA), or a group given a 'typical American diet' (TAD), based largely on a Western diet pattern. By design, women maintained their body weight. Fasting plasma and PBMC were collected at wk. 0 (baseline) and at wk. 8 (post-intervention). Sixteen plasma markers of inflammation and eight PBMC cytokines were measured at both time points, to evaluate if the diet had a significant effect on concentrations of these inflammatory markers. Data were analyzed using ANCOVA, followed by multiple-comparison adjustment using Benjamini-Hochberg method. RESULTS: Significant changes observed in Serum Amyloid A (SAA) and Matrix Metalloproteinase 3 (MMP3) in plasma did not retain significance upon multiple comparison adjustment. SAA: p = 0.044, adj p = 0.450; DGA mean change [95% CI] = - 12.6[- 32.3 to 7.04]; TAD mean change [95% CI] = - 2.24 [- 9.99 to 5.51]. MMP3: p = 0.014, adj p = 0.35; DGA mean change [95% CI] = 2.72[- 4.16 to 9.59]; TAD mean change [95% CI] = - 0.98[- 16.7 to 14.7]). Other inflammation markers were not differently altered by DGA relative to TAD. Effect size of change (Cohens d) indicated a large/medium-large effect of intervention on MMP3 and CRP, and medium effect on IL-6. CONCLUSIONS: No statistically significant changes were observed in the immune markers examined in this study. The biological roles and magnitude of the non-significant differences seen with two variables, CRP and MMP3, suggest that they be examined in future studies. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02298725.

15.
BMC Nutr ; 8(1): 95, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050800

RESUMO

BACKGROUND: The effect of genetic polymorphisms on fasting blood lipid levels have been widely studied but the effects of these within the context of a high-fat meal challenge remain less characterized. The current study aimed to investigate the association of SNPs in lipoprotein-related genes with blood lipid profiles in healthy adults in the U.S. METHODS: Subjects (n = 393) between 18-66 years of age with BMIs ranging from 18.5-45 kg/m2 were enrolled the cross-sectional Nutritional Phenotyping Study. Among them, 349 subjects (men: 48%; women: 52%) gave consent for genotyping. SNPs in APOA5, APOB, APOC3, APOE, and LDLR were assessed. The association between lipid markers and genotypes was tested separately for each SNP with analysis of variance (ANOVA), adjusted for sex, age, and BMI. We also examined two-factor interactions between SNPs and sex, age, or BMI. RESULTS: Women carrying the C allele of rs3135506 in APOA5 or men carrying the C allele of rs429358 in APOE had reduced HDL-cholesterol levels during fasting and postprandially. The C allele in APOE was also correlated to increased LDL-C levels. The TT genotype of rs2854116 in APOC3 was associated with elevated total cholesterol. Additive effect of the risk alleles of APOA5 and APOE or APOC3 and APOE was detected. Nevertheless, the tested SNPs had little impact on the postprandial triglyceride responses to the high-fat challenge meal. We found no significant effects of SNPs in APOB (rs1042034) or LDLR (rs2228671) on triglycerides, cholesterol, or free fatty acid levels. CONCLUSIONS: In healthy adults, fasting and postprandial cholesterol levels are strongly correlated with the tested APOA5, APOE, and APOC3 genotypes. Sex contributes to the genetic impact of the tested SNPs on lipid profiles. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02367287. Registered February 20, 2015, https://clinicaltrials.gov/ct2/show/NCT02367287 .

16.
J Nutr ; 140(3): 542-50, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20053937

RESUMO

Cutaneous cholecalciferol synthesis has not been considered in making recommendations for vitamin D intake. Our objective was to model the effects of sun exposure, vitamin D intake, and skin reflectance (pigmentation) on serum 25-hydroxyvitamin D (25[OH]D) in young adults with a wide range of skin reflectance and sun exposure. Four cohorts of participants (n = 72 total) were studied for 7-8 wk in the fall, winter, spring, and summer in Davis, CA [38.5 degrees N, 121.7 degrees W, Elev. 49 ft (15 m)]. Skin reflectance was measured using a spectrophotometer, vitamin D intake using food records, and sun exposure using polysulfone dosimeter badges. A multiple regression model (R(2) = 0.55; P < 0.0001) was developed and used to predict the serum 25(OH)D concentration for participants with low [median for African ancestry (AA)] and high [median for European ancestry (EA)] skin reflectance and with low [20th percentile, approximately 20 min/d, approximately 18% body surface area (BSA) exposed] and high (80th percentile, approximately 90 min/d, approximately 35% BSA exposed) sun exposure, assuming an intake of 200 iu/d (5 ug/d). Predicted serum 25(OH)D concentrations for AA individuals with low and high sun exposure in the winter were 24 and 42 nmol/L and in the summer were 40 and 60 nmol/L. Corresponding values for EA individuals were 35 and 60 nmol/L in the winter and in the summer were 58 and 85 nmol/L. To achieve 25(OH)D > or =75 nmol/L, we estimate that EA individuals with high sun exposure need 1300 iu/d vitamin D intake in the winter and AA individuals with low sun exposure need 2100-3100 iu/d year-round.


Assuntos
Pigmentação da Pele/fisiologia , Vitamina D/análogos & derivados , Vitamina D/administração & dosagem , Vitamina D/farmacologia , Adulto , Negro ou Afro-Americano , California , Registros de Dieta , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Necessidades Nutricionais , Estações do Ano , Luz Solar , Vitamina D/sangue , População Branca , Adulto Jovem
17.
J Nutr ; 140(12): 2128-33, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20943956

RESUMO

To assist with the evaluation of zinc (Zn) intervention programs, information is needed on the magnitude and velocity of response of plasma Zn concentration following changes in Zn intake. Our objective in this study was to measure plasma Zn concentration of healthy adult men before and after initiation and discontinuation of 1 of 2 dosages of Zn supplements or placebo. We conducted a randomized, double-blind, placebo-controlled trial in 58 apparently healthy males aged 19-54 y. Participants received 1 of 3 liquid supplements daily for 21 d: 10 or 20 mg Zn/d, as Zn sulfate, or placebo. Fasting plasma Zn concentrations were measured on 14 occasions before, during, and after supplementation. Data were analyzed using mixed-model ANCOVA. The plasma Zn concentration was related to day of study (P < 0.0001) and study group (P < 0.0001). Controlling for baseline concentrations, plasma Zn concentrations were consistently elevated above baseline by d 5 among individuals in both of the Zn-supplemented groups compared with those receiving placebo supplements, regardless of their initial plasma Zn concentration. There were no significant group-wise differences between those who received either 10 or 20 mg/d Zn. Plasma Zn concentrations of supplemented individuals declined following withdrawal of supplementation and within 2 wk no longer differed from those of the placebo group. Change in the plasma Zn concentration is a useful indicator to monitor compliance with, and possibly effectiveness of, Zn supplementation programs. To ensure accurate interpretation of the results, samples should be collected while the intervention is still in progress.


Assuntos
Zinco/sangue , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Valores de Referência , Reprodutibilidade dos Testes , Zinco/administração & dosagem
18.
Br J Nutr ; 102(6): 835-41, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19267950

RESUMO

We investigated the adverse effect of phytate on mineral absorption and the effect of dietary phytate and age on the relationship between faecal phytate and faecal mineral excretion. Fourteen young women (aged 19-24 years) and fourteen elderly women (64-75 years) were studied for two metabolic periods (MP). In MP1, the subjects consumed a controlled high-phytate (HP) diet for 10 d; in MP2, they were on a low-phytate (LP) diet for 10 d. In each period, diet samples and complete faecal samples for 5 d were collected to analyse phytate and mineral contents. Mineral concentrations in diet and faeces were measured by inductively coupled plasma-atomic emission spectrometry. Linear regression analysis was used to examine the associations between faecal phytate and mineral excretion. The degradation rate of dietary phytate was about 77% for young women, which was significantly lower than that of elderly women (86%) (P < 0.05). Faecal phytate excretion was positively correlated with mineral excretion (Ca, P, Fe and Zn) in both the HP and LP diet groups in young women (P < 0.05). The linear relationship tended to be greater during the LP diet period compared with the HP diet period in young women. However, no association was found between phytate excretion and mineral excretion in elderly women. In summary, undegraded dietary phytate (10-20%) had a negative effect on mineral absorption in young women, and the relationship between faecal phytate and mineral excretion was affected by both dietary phytate and age.


Assuntos
Fezes/química , Absorção Intestinal/efeitos dos fármacos , Ácido Fítico/farmacologia , Oligoelementos/farmacocinética , Fatores Etários , Idoso , Antropometria , Dieta , Feminino , Análise de Alimentos/métodos , Humanos , Absorção Intestinal/fisiologia , Pessoa de Meia-Idade , Ácido Fítico/administração & dosagem , Ácido Fítico/farmacocinética , Oligoelementos/administração & dosagem , Oligoelementos/análise , Adulto Jovem
19.
Am J Clin Nutr ; 110(6): 1465-1475, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504101

RESUMO

BACKGROUND: Dietary phytate inhibits zinc absorption from composite meals in adults. OBJECTIVE: The objective of this study was to investigate the effect of adding exogenous phytase to a small-quantity lipid-based nutrient supplement (SQ-LNS) on zinc absorption among young children. METHODS: In a double-blind randomized controlled trial, intraindividual differences in fractional and total absorption of zinc (FAZ and TAZ, respectively) from a millet-based porridge containing SQ-LNS with and without phytase were measured in 30 asymptomatic children 18-23 mo of age in the Kiang West district of The Gambia. Using a crossover design, children received for 1 d each porridge test meals with 20 g SQ-LNS containing 8 mg zinc and either 1) exogenous phytase or 2) no exogenous phytase. The test meals were provided on consecutive days in randomized order. FAZ was measured using a triple stable isotope tracer ratio technique with Zn-67 and Zn-70 as oral tracers and Zn-68 as the intravenous tracer. RESULTS: Twenty-six participants completed the study. The prevalence of stunting and wasting were 20% and 13%, respectively; no children had low plasma zinc concentrations (<65 µg/dL). Total mean ± SD dietary zinc intake from the test meals was 7.3 ± 2.2 mg (phytate:zinc molar ratio = 3.1 ± 0.3, not accounting for phytase activity). Mean FAZ increased from 8.6% ± 1.3% to 16.0% ± 1.3% when exogenous phytase was added to the SQ-LNS product (P < 0.001). Mean TAZ from test meals containing SQ-LNS with phytase was more than double that from test meals containing SQ-LNS without phytase (1.1 ± 0.1 mg and 0.5 ± 0.1 mg, respectively; P < 0.001). CONCLUSIONS: The addition of exogenous phytase to SQ-LNS increased both FAZ and TAZ. These results suggest that phytate reduction may be an important strategy to increase zinc absorption among young children. This trial was registered at clinicaltrials.gov as NCT02668133.


Assuntos
6-Fitase/administração & dosagem , Milhetes/metabolismo , Zinco/sangue , Suplementos Nutricionais/análise , Feminino , Aditivos Alimentares/análise , Aditivos Alimentares/metabolismo , Gâmbia , Humanos , Lactente , Metabolismo dos Lipídeos , Lipídeos/análise , Masculino , Micronutrientes/metabolismo , Milhetes/química , Ácido Fítico/sangue
20.
Br J Sports Med ; 41(3): 156-61, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17138634

RESUMO

OBJECTIVE: To examine the effect of acute exhaustive exercise versus rest on short-term zinc kinetics in men. DESIGN: Crossover design, wherein all subjects were their own control. SETTING: University setting, where subjects were free living. PARTICIPANTS: 12 healthy, sedentary men, 25-35 years of age. INTERVENTIONS: (70)Zn was infused 10 min after exercise or at rest. Plasma zinc concentrations were measured at baseline and 2, 5, 10, 15, 30, 45, 60, 75, 90 and 120 min after exercise or rest. Haematocrit was measured before and after exercise to assess changes in plasma volume. MAIN OUTCOME MEASUREMENTS: Plasma zinc (primary), serum creatine kinase and serum cortisol concentrations (secondary). RESULTS: Plasma zinc concentrations decreased (p<0.05) after exercise, with a mean (SD) nadir of 13.9% (4.1%) observed at 70 min after exercise. There were increases in the size of the rapidly exchangeable plasma zinc pool (Qa; from 3.1 (0.2) to 3.6 (0.2) mg; p<0.05) and the liver zinc pool (Qb; from 10.2 (0.6) to 11.4 (0.8) mg; p = 0.12). CONCLUSION: Exercise seems to cause a shift of plasma zinc into the interstitial fluid and liver after exercise, which may reflect the acute stress response of strenuous exercise.


Assuntos
Exercício Físico/fisiologia , Estilo de Vida , Zinco/metabolismo , Adulto , Estudos Cross-Over , Dieta , Humanos , Cinética , Masculino , Esforço Físico/fisiologia
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