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1.
Nutrients ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34444975

RESUMO

This review evaluated the effects of milk-based protein supplementation on resistance training (RT)-induced gains in lean body mass or fat free mass (LBM/FFM) and muscle strength for older adults. A systematic search of PubMed, Scopus and EBSCOhost/SPORTDiscus was conducted. Eligibility criteria: Randomized controlled trials comparing all types of milk-based protein supplements with control supplements for the training older adults at mean age ≥ 60 y. Twenty studies were included in the qualitative synthesis, whilst seventeen studies were included in the quantitative synthesis. A dose of 10-15 g of milk protein supplementation was sufficient to augment RT-induced LBM/FFM. Intriguingly, four out of five studies show negative effect of whey protein supplementation at the same dose range (or even higher) compared with control supplementation (-0.49 kg, 95% CI: -0.69, -0.29, I2 = 14%, Z = 4.82, p < 0.001). For milk-based protein supplementation, RT-induced improvements in muscle strength were observed only when the protein doses ≥22 g (+0.66 kg, 95% CI: 0.07, 1.25, I2 = 0%, Z = 2.18, p = 0.03). Conclusion: Milk protein is superior to whey protein in enhancing RT-induced LBM/FFM gains for older adults. Optimal daily protein intake can dilute the protein supplementation effect.


Assuntos
Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Proteínas do Leite/farmacologia , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento Resistido , Idoso , Idoso de 80 Anos ou mais , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Soro do Leite/farmacologia
2.
Physiol Rep ; 8(2): e14360, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31994353

RESUMO

Most of the filtered glucose is reabsorbed in the early proximal tubule by the sodium-glucose cotransporter SGLT2. The glycosuric effect of the SGLT2 inhibitor ipragliflozin is linked to a diuretic and natriuretic effect that activates compensatory increases in fluid and food intake to stabilize body fluid volume (BFV). However, the compensatory mechanisms that are activated on the level of renal tubules remain unclear. Type 2 diabetic Goto-Kakizaki (GK) rats were treated with vehicle or 0.01% (in diet) ipragliflozin with free access to fluid and food. After 8 weeks, GK rats were placed in metabolic cages for 24-hr. Ipragliflozin decreased body weight, serum glucose and systolic blood pressure, and increased fluid and food intake, urinary glucose and Na+ excretion, urine volume, and renal osmolar clearance, as well as urine vasopressin and solute-free water reabsorption (TcH2O). BFV, measured by bioimpedance spectroscopy, and fluid balance were similar among the two groups. Urine vasopressin in ipragliflozin-treated rats was negatively and positively associated with fluid balance and TcH2O, respectively. Ipragliflozin increased the renal membrane protein expression of SGLT2, aquaporin (AQP) 2 phosphorylated at Ser269 and vasopressin V2 receptor. The expression of SGLT1, GLUT2, AQP1, and AQP2 was similar between the groups. In conclusion, the SGLT2 inhibitor ipragliflozin induced a sustained glucosuria, diuresis, and natriuresis, with compensatory increases in fluid intake and vasopressin-induced TcH2O in proportion to the reduced fluid balance to maintain BFV. These results indicate that the osmotic diuresis induced by SGLT2 inhibition stimulates compensatory fluid intake and renal water reabsorption to maintain BFV.


Assuntos
Líquidos Corporais/metabolismo , Diurese/fisiologia , Osmose/fisiologia , Reabsorção Renal/fisiologia , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Vasopressinas/urina , Água/metabolismo , Animais , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Compartimentos de Líquidos Corporais/metabolismo , Líquidos Corporais/efeitos dos fármacos , Diurese/efeitos dos fármacos , Diuréticos Osmóticos/farmacologia , Glucosídeos/farmacologia , Osmose/efeitos dos fármacos , Ratos , Reabsorção Renal/efeitos dos fármacos , Tiofenos/farmacologia
3.
Am J Clin Nutr ; 106(6): 1375-1383, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29092886

RESUMO

Background: The Recommended Daily Allowance (RDA) for protein intake in the adult population is widely promoted as 0.8 g · kg-1 · d-1 Aging may increase protein requirements, particularly to maintain muscle mass.Objective: We investigated whether controlled protein consumption at the current RDA or twice the RDA (2RDA) affects skeletal muscle mass and physical function in elderly men.Design: In this parallel-group randomized trial, 29 men aged >70 y [mean ± SD body mass index (in kg/m2): 28.3 ± 4.2] were provided with a complete diet containing either 0.8 (RDA) or 1.6 (2RDA) g protein · kg-1 · d-1, aimed to balance energy needs. Before treatment and after 10 wk of intervention, whole-body and appendicular lean mass were measured by using dual-energy X-ray absorptiometry. Knee-extension peak power was measured with dynamometry.Results: Both groups were found to have been in a moderate negative energy balance (mean ± SD RDA: 209 ± 213 kcal/d; 2RDA 145 ± 214 kcal/d; P= 0.427 for difference between the groups). In comparison with RDA, whole-body lean mass increased in 2RDA (P = 0.001; 1.49 ± 1.30 kg, P < 0.001 compared with -0.55 ± 1.49 kg, P = 0.149). This difference was mostly accounted for by an increase in trunk lean mass found in 2RDA (+1.39 ± 1.09 kg, P < 0.001). Appendicular lean mass also decreased in RDA compared with 2RDA (P = 0.022), driven by a reduction in RDA (-0.64 ± 0.91 kg, P = 0.005 compared with 0.11 ± 0.57 kg, P = 0.592). Adjusting for energy imbalances did not alter these findings. Knee-extension peak power was also differently affected (P = 0.012; 26.6 ± 47.7 W, P = 0.015 in 2RDA compared with -11.7 ± 31.0 W, P = 0.180 in RDA).Conclusions: Consumption of a diet providing 2RDA for protein compared with the current guidelines was found to have beneficial effects on lean body mass and leg power in elderly men. These effects were not explained by differences in energy balance. This trial was registered at the Australia New Zealand Clinical Trial Registry (www.anzctr.org.au) as ACTRN12616000310460.


Assuntos
Envelhecimento/fisiologia , Composição Corporal/efeitos dos fármacos , Dieta , Proteínas Alimentares/farmacologia , Comportamento Alimentar , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Índice de Massa Corporal , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Metabolismo Energético , Humanos , Perna (Membro) , Masculino , Necessidades Nutricionais , Tamanho do Órgão , Recomendações Nutricionais
4.
Int J Sport Nutr Exerc Metab ; 24(3): 276-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24281841

RESUMO

Bovine colostrum is the first milk secreted by cows after parturition and has high levels of protein, immunoglobulins, and various growth factors. We determined the effects of 8 weeks of bovine colostrum supplementation versus whey protein during resistance training in older adults. Males (N = 15, 59.1 ± 5.4 y) and females (N = 25, 59.0 ± 6.7 y) randomly received (double-blind) 60 g/d of colostrum or whey protein complex (containing 38 g protein) while participating in a resistance training program (12 exercises, 3 sets of 8-12 reps, 3 days/ week). Strength (bench press and leg press 1-RM), body composition (by dual energy x-ray absorptiometry), muscle thickness of the biceps and quadriceps (by ultrasound), cognitive function (by questionnaire), plasma insulin-like growth factor-1 (IGF-1) and C-reactive protein (CRP, as a marker of inflammation), and urinary N-telopeptides (Ntx, a marker of bone resorption) were determined before and after the intervention. Participants on colostrum increased leg press strength (24 ± 29 kg; p < .01) to a greater extent than participants on whey protein (8 ± 16 kg) and had a greater reduction in Ntx compared with participants on whey protein (-15 ± 40% vs. 10 ± 42%; p < .05). Bench press strength, muscle thickness, lean tissue mass, bone mineral content, and cognitive scores increased over time (p < .05) with no difference between groups. There were no changes in IGF-1 or CRP. Colostrum supplementation during resistance training was beneficial for increasing leg press strength and reducing bone resorption in older adults. Both colostrum and whey protein groups improved upper body strength, muscle thickness, lean tissue mass, and cognitive function.


Assuntos
Reabsorção Óssea/prevenção & controle , Cognição/efeitos dos fármacos , Colostro , Suplementos Nutricionais , Proteínas do Leite/farmacologia , Músculo Esquelético/efeitos dos fármacos , Treinamento Resistido , Animais , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/metabolismo , Bovinos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Leite/uso terapêutico , Força Muscular/efeitos dos fármacos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Peptídeos/urina , Proteínas do Soro do Leite
5.
Nutr Res ; 33(8): 608-12, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23890349

RESUMO

Lean body mass (LBM) is important to maintain physical function during aging. We hypothesized that dietary protein intake and leisure-time physical activity are associated with LBM in community-dwelling older adults. To test the hypothesis, participants (n = 237; age, 65-92 years) did 3-day weighed food records and reported physical activity. Body composition was assessed using dual-energy x-ray absorptiometry. Protein intake was 0.98 ± 0.28 and 0.95 ± 0.29 g/kg body weight in male and female participants, respectively. Protein intake (in grams per kilogram of body weight) was associated with LBM (in kilograms); that is, the differences in LBM were 2.3 kg (P < .05) and 2.0 kg (P = .054) between the fourth vs the first and the fourth vs the second quartiles of protein intake, respectively. Only a minor part of this association was explained by increased energy intake, which follows an increased protein intake. Our study shows that dietary protein intake was positively associated with LBM in older adults with a mean protein intake higher than the current recommended daily allowance of 0.8 g/kg per day. Leisure-time physical activity, predominantly consisting of endurance type exercises, was not related to LBM in this group.


Assuntos
Composição Corporal , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Dieta , Proteínas Alimentares/administração & dosagem , Exercício Físico , Absorciometria de Fóton , Idoso , Envelhecimento , Compartimentos de Líquidos Corporais/metabolismo , Registros de Dieta , Proteínas Alimentares/farmacologia , Ingestão de Energia , Feminino , Humanos , Masculino , Recomendações Nutricionais , Características de Residência , Fatores Sexuais
6.
J Complement Integr Med ; 102013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23652638

RESUMO

In this open, clinically based, weight modification program, we determined in six sedentary obese adults (five women; one male; age range 30-62 years) that the combination of a modified calorie diet plus PGX® meal replacement and PGX® supplementation resulted in a significant reduction in several cardiovascular risk factors over a 12-week time period. This included a significant improvement in lipids (-0.98 mmol/l LDL-C), reduction in average weight (-9.2 kg), mean reduction in fat (-4.1%) and an increase in fat-free mass (2.8%).


Assuntos
Composição Corporal/efeitos dos fármacos , Restrição Calórica , Doenças Cardiovasculares/prevenção & controle , Fibras na Dieta/uso terapêutico , Obesidade/dietoterapia , Redução de Peso/efeitos dos fármacos , Programas de Redução de Peso , Tecido Adiposo/efeitos dos fármacos , Adulto , Alginatos/farmacologia , Alginatos/uso terapêutico , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Dieta Redutora , Fibras na Dieta/farmacologia , Suplementos Nutricionais , Feminino , Ácido Glucurônico/farmacologia , Ácido Glucurônico/uso terapêutico , Ácidos Hexurônicos/farmacologia , Ácidos Hexurônicos/uso terapêutico , Humanos , Masculino , Mananas/farmacologia , Mananas/uso terapêutico , Pessoa de Meia-Idade , Obesidade/sangue , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/uso terapêutico , Fatores de Risco , Comportamento Sedentário
7.
J Nutr ; 143(5): 591-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23446962

RESUMO

Energy-restricted high-protein diets (HPDs) have shown favorable results for body weight (BW) management, yet studies differ in their outcomes depending on the dietary protein content. Our objective was to determine the effects of dietary protein content on BW loss-related variables during a 6-mo energy restriction with the use of diets containing protein at the level of requirement [normal-protein diet (NPD), 0.8 g · kg BW(-1) (.) d(-1)] and above (HPD, 1.2 g · kg BW(-1) (.) d(-1)). In overweight and obese participants (24 men and 48 women), BW, body composition, and metabolic responses were assessed before and after subsequent energy intakes of 100, 33, and 67% of the original individual daily energy requirements. Protein intake was consistent in the NPD (0.8 ± 0.3 g · kg BW(-1) (.) d(-1)) and HPD (1.2 ± 0.3 g · kg BW(-1) (.) d(-1)) groups throughout the study (P < 0.001). BMI and body fat mass similarly decreased in the NPD and HPD groups (P < 0.01). Fat free mass (FFM), resting energy expenditure (REE) compared with predicted REE, and diastolic blood pressure (DBP) changed favorably with the HPD compared with the NPD group after BW loss (P < 0.05). A NPD of 0.8 g · kg BW(-1) (.) d(-1) is sufficient for BW management, whereas a HPD of 1.2 g · kg BW(-1) (.) d(-1) is necessary for preservation of REE and a stronger initial sparing effect of FFM and lowering of DBP.


Assuntos
Metabolismo Basal/efeitos dos fármacos , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Dieta Redutora , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Obesidade/dietoterapia , Redução de Peso/efeitos dos fármacos , Tecido Adiposo , Adulto , Índice de Massa Corporal , Restrição Calórica , Proteínas Alimentares/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necessidades Nutricionais
8.
Eur J Clin Nutr ; 67(8): 821-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23486511

RESUMO

BACKGROUND/OBJECTIVES: A few previous studies indicate that protein supplementation increases gains in muscle mass and strength during a resistance exercise program. The purpose of this study was to investigate whether whey protein supplementation results in greater increases in lean body mass, muscle strength and physical function in elderly individuals during 12 weeks of resistance exercise when compared to isocaloric carbohydrate supplementation. SUBJECTS/METHODS: A total of 161 men and women, 65-91 years old, participated in a randomized, controlled, double-blind intervention study, involving dietary supplementation and a 12-week resistance exercise program, designed to increase muscle mass and strength of all major muscle groups. Participants exercised three times a week and received either 20 g of whey protein (n=83) or isocaloric carbohydrate (n=78) in liquid form immediately after each workout. Data were obtained at baseline and end point. RESULTS: The primary outcomes, lean body mass, strength and physical function increased significantly during the course of the study. Type of dietary supplementation did not influence gains in lean body mass (P=0.365), quadriceps strength (P=0.776) or performance during a 6-min walk (P=0.726) or a timed up-and-go test (P=0.151). Twenty participants discontinued the intervention. CONCLUSIONS: Ingestion of 20 g of whey protein immediately after resistance exercise three times per week, does not lead to greater gains in lean body mass, strength and physical function in elderly people with sufficient energy and protein intakes when compared to isocaloric carbohydrate.


Assuntos
Carboidratos da Dieta/farmacologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Proteínas do Leite/farmacologia , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento Resistido , Idoso , Idoso de 80 Anos ou mais , Composição Corporal/efeitos dos fármacos , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Proteínas Alimentares/farmacologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Aptidão Física/fisiologia , Caminhada , Proteínas do Soro do Leite
9.
Br J Nutr ; 109(10): 1755-64, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23110765

RESUMO

SCFA are produced in the gut by bacterial fermentation of undigested carbohydrates. Activation of the Gαi-protein-coupled receptor GPR41 by SCFA in ß-cells and sympathetic ganglia inhibits insulin secretion and increases sympathetic outflow, respectively. A possible role in stimulating leptin secretion by adipocytes is disputed. In the present study, we investigated energy balance and glucose homoeostasis in GPR41 knockout mice fed on a standard low-fat or a high-fat diet. When fed on the low-fat diet, body fat mass was raised and glucose tolerance was impaired in male but not female knockout mice compared to wild-type mice. Soleus muscle and heart weights were reduced in the male mice, but total body lean mass was unchanged. When fed on the high-fat diet, body fat mass was raised in male but not female GPR41 knockout mice, but by no more in the males than when they were fed on the low-fat diet. Body lean mass and energy expenditure were reduced in male mice but not in female knockout mice. These results suggest that the absence of GPR41 increases body fat content in male mice. Gut-derived SCFA may raise energy expenditure and help to protect against obesity by activating GPR41.


Assuntos
Tecido Adiposo/metabolismo , Composição Corporal/genética , Gorduras na Dieta/farmacologia , Metabolismo Energético/genética , Ácidos Graxos Voláteis/metabolismo , Obesidade/genética , Receptores Acoplados a Proteínas G/genética , Tecido Adiposo/efeitos dos fármacos , Animais , Bactérias/metabolismo , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Compartimentos de Líquidos Corporais/metabolismo , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Gorduras na Dieta/metabolismo , Feminino , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Intolerância à Glucose/genética , Coração/efeitos dos fármacos , Insulina/metabolismo , Secreção de Insulina , Leptina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/efeitos dos fármacos , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/prevenção & controle , Tamanho do Órgão , Receptores Acoplados a Proteínas G/metabolismo , Fatores Sexuais
10.
Nutr Res ; 32(12): 911-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23244536

RESUMO

The relationships between conjugated linoleic acid (CLA) status, bone, body composition, and the effect of CLA on calciotropic hormones are unclear. A cross-sectional study was designed to examine the association between c9, t11 CLA status in erythrocyte membranes (RBC) and body composition. This preceded a dose-response trial investigating if c9, t11 CLA affected parathyroid hormone (PTH). It was hypothesized that (1) higher c9, t11 CLA status in RBC will be associated with a lower fat and higher bone mass and that (2) PTH will be reduced by 30% after supplementation of c9, t11 CLA. Fifty-four men (age, 19-53 years) were included in the cross-sectional analysis, of which 31 were studied in the dose-response trial and randomized to 1 of 3 groups: placebo (n = 10), 1.5 g/d (n = 11), or 3.0 g/d (n = 10) of c9, t11 CLA for 16 weeks. Men with RBC c9, t11 CLA status above the median had higher whole body bone mineral density (BMD) (1.359 ± 0.024 vs 1.287 ± 0.023 g/cm(2); P = .04) and whole body lean mass (WBL) percentage (78.8% ± 0.9% vs 75.3% ± 1.0%; P = .01), whereas body mass index (24.8 ± 0.5 kg/m(2) vs 27.3 ± 0.9 kg/m(2); P = .01) and whole body fat mass percentage (17.3% ± 0.9% vs 21.3% ± 1.1%; P = .007) were lower. In regression analysis, RBC c9, t11 CLA status accounted for a significant proportion (r(2) = 0.10) of the variation in whole body BMD (P = .03). There were no time or treatment differences among any bone or biomarkers of bone metabolism including PTH. These findings indicate that RBC c9, t11 CLA status, a reflection of long-term (~4 months) dietary CLA intake, positively relates to BMD. However, c9, t11 CLA supplementation does not appear to affect PTH in healthy men.


Assuntos
Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Eritrócitos/efeitos dos fármacos , Ácidos Linoleicos Conjugados/farmacologia , Hormônio Paratireóideo/sangue , Tecido Adiposo/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Índice de Massa Corporal , Membrana Celular , Estudos Transversais , Gorduras na Dieta/sangue , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Humanos , Ácidos Linoleicos Conjugados/sangue , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Análise de Regressão
11.
Br J Nutr ; 108 Suppl 2: S122-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23107523

RESUMO

Red meat intake has been frequently associated with the development of coronary artery disease and type 2 diabetes but vegetable protein has been associated with protection from these diseases. Whether this is related to the protein per se or to the increased polyunsaturated fat or higher fibre levels associated with more vegetarian diets is not clear. High protein diets are associated with greater satiety and in some studies are associated with greater weight loss compared with high carbohydrate diets especially in an ad libitum design. These diets also lower plasma triglyceride and blood pressure and sometimes spare lean mass. There appear to be no harmful effects of high protein diets on bone density or renal function in weight loss studies.


Assuntos
Doença da Artéria Coronariana/prevenção & controle , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta Redutora , Proteínas Alimentares/uso terapêutico , Obesidade/dietoterapia , Verduras/química , Redução de Peso/efeitos dos fármacos , Animais , Pressão Sanguínea , Composição Corporal/efeitos dos fármacos , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Doença da Artéria Coronariana/complicações , Diabetes Mellitus Tipo 2/complicações , Dieta com Restrição de Carboidratos , Dieta Vegetariana , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Fibras na Dieta/farmacologia , Proteínas Alimentares/farmacologia , Humanos , Rim/efeitos dos fármacos , Carne , Obesidade/complicações , Saciação/efeitos dos fármacos , Triglicerídeos/sangue
12.
J Pharmacol Toxicol Methods ; 65(2): 75-82, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22353670

RESUMO

INTRODUCTION: Bioimpedance spectroscopy (BIS) has been used in human and large animal research to assess body fluid compartment volumes (BFC) such as total body water (TBW), extracellular fluid volume (ECFV), and intracellular fluid volume (ICFV). To date, the application of BIS for determination of BFC in small research animals has been limited. METHODS: We sought to evaluate the sensitivity and consistency of BIS for the determination of BFC in male SD rats. Thus, in separate series of experiments, we a) compared BFC values determined using BIS to BFC values obtained using radioisotope indicator dilution methods; b) examined day-to-day intra- and inter-rat BFC variability in small (267.8±5.4 g) and large (372.6±5.6 g) rats (n=8/group) as compared to empirical normative mammalian values; c) evaluated the sensitivity of BIS to detect time-dependent responses to repeated administration of a potent diuretic; and d) compared empirically generated BFC data to predicted osmotically-induced ECFV and ICFV shifts in response to i.v. administration of hypotonic (0.3%), isotonic (0.9%) or hypertonic (3.0%) saline (n=6/concentration). RESULTS: BFC values generated using radioisotope dilution agreed with those generated using BIS. BIS reliably detected differences between small and large rats (p<0.001), and was associated with low (<3.5%) day-to-day, intra-animal coefficient of variation (%=Standard Deviation/mean). BIS detected small reductions (~10%) in ECFV induced by as few as 2 days of the loop diuretic, furosemide, relative to vehicle treatment (70.8±1.5 ml vs. 84.0±1.5 ml; respectively, p<0.05). BIS rapidly detected shifts between ECFV and ICFV in response to osmotic saline challenge, and these responses were similar to physiologically predicted responses. DISCUSSION: The current studies support using BIS as a means of sensitively and reliably performing repeated measurements of BFC in rats of a) differing sizes, b) in response to therapeutic agents known to influence renal sodium handling and c) in response to osmotic challenge.


Assuntos
Compartimentos de Líquidos Corporais/fisiologia , Água Corporal/fisiologia , Impedância Elétrica , Líquido Extracelular/fisiologia , Animais , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Compartimentos de Líquidos Corporais/química , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Água Corporal/efeitos dos fármacos , Líquido Extracelular/efeitos dos fármacos , Injeções Intravenosas , Masculino , Técnica de Diluição de Radioisótopos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cloreto de Sódio/administração & dosagem
13.
Nutrition ; 28(2): 182-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21872432

RESUMO

OBJECTIVE: Aging is characterized by alterations in body composition such as an increase in body fat and decreases in muscle mass (sarcopenia) and bone density (osteopenia). Leucine supplementation has been shown to acutely stimulate protein synthesis and to decrease body fat. However, the long-term effect of consistent leucine supplementation is not well defined. This study investigated the effect of leucine supplementation during aging. METHODS: Six-month-old rats were divided into three groups: an adult group (n = 10) euthanized at 6 mo of age, a leucine group (n = 16) that received a diet supplemented with 4% leucine for 40 wk, and a control group (n = 19) that received the control diet for 40 wk. The following parameters were evaluated: body weight, food intake, chemical carcass composition, indicators of acquired chronic diseases, and indicators of protein nutritional status. RESULTS: Body weight and fat were lower in the leucine group after 40 wk of supplementation compared with the control group but still higher than in the adult group. The lipid and glycemic profiles were equally altered in the control and leucine groups because of aging. In addition, leucine supplementation did not affect the changes in protein status parameters associated with aging, such as decreases in body and muscle protein and total serum protein. CONCLUSION: The results indicate that leucine supplementation attenuates body fat gain during aging but does not affect risk indicators of acquired chronic diseases. Furthermore, supplemented animals did not show signs of a prevention of the decrease in lean mass associated with aging.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Envelhecimento/fisiologia , Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Leucina/farmacologia , Obesidade/prevenção & controle , Proteínas/metabolismo , Tecido Adiposo/metabolismo , Fatores Etários , Animais , Glicemia/metabolismo , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Compartimentos de Líquidos Corporais/metabolismo , Peso Corporal/efeitos dos fármacos , Doença Crônica , Leucina/administração & dosagem , Lipídeos/sangue , Masculino , Estado Nutricional , Obesidade/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Risco
14.
Nutrition ; 28(6): 630-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22196981

RESUMO

OBJECTIVE: Infection with hepatitis C virus (HCV) is a serious public health problem worldwide. In clinical studies, weight loss has been reported in 11% to 29% of patients treated with pegylated interferon-α-2a/2b. Few reports have tried to explain such a weight loss. The aim of this study was to evaluate nutritional status, body composition, and resting energy expenditure (REE) in patients with chronic hepatitis C before and during treatment with pegylated interferon and ribavirin. METHODS: This was a prospective study with the evaluation of patients with hepatitis C virus before and after 12 wk of treatment with pegylated interferon and ribavirin. The evaluation consisted of anthropometry (weight, height, body mass index, and waist circumference), and body composition was determined by bioelectrical impedance analysis. The REE of each individual was obtained by indirect calorimetry. To compare the two phases of treatment, the Wilcoxon test was used. The significance level was 5%. RESULTS: Subjects had significant weight loss during treatment with a consequent decrease in body mass index. This weight decrease was accompanied by a significant decrease in body fat and no decrease in fat-free mass. There was a significant decrease in energy intake as assessed by 24-h recall. However, there was no change in REE and in REE corrected for fat-free mass. CONCLUSION: Our study of patients with hepatitis C treatment showed that these patients had significant weight loss and this was not associated with changes in energy expenditure. However, we observed a significant decrease in energy intake, pointing to a possible need for intervention measures to decrease the damage.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Metabolismo Basal/efeitos dos fármacos , Índice de Massa Corporal , Ingestão de Energia/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Redução de Peso/efeitos dos fármacos , Tecido Adiposo/metabolismo , Adulto , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Registros de Dieta , Feminino , Hepatite C Crônica/metabolismo , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Estudos Prospectivos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Padrão de Cuidado , Estatísticas não Paramétricas
15.
J Nutr Health Aging ; 15(10): 883-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22159777

RESUMO

This study was aimed to examine the effect of vitamin C/E intake alone or combined with resistance training on antioxidant/pro-oxidant status, muscle strength and body composition in an elderly population. Fifty-seven men and women with a mean age of 65.6 ± 3.8 years were recruited and randomized in a double-blind fashion into four groups: control-placebo; resistance training (RT); vitamins C/E supplementation (AS); AS+RT. Oxidative stress status and metabolic and lipid profiles were determined at baseline and after six months. Fat-free mass and fat mass measured by DXA were similar at baseline for all groups. At six month, there was a significant difference among the groups as a function of vitamin E supplementation. Moreover, although there was no effect on pro-oxidative parameters, a significant effect on body composition was noted, but no difference was noted on strength gain. The combination of RT+AS had a positive effect on the plasma antioxidant profile but not on the pro-oxidant status.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Composição Corporal , Músculo Esquelético/fisiologia , Estresse Oxidativo , Treinamento Resistido , Vitamina E/farmacologia , Absorciometria de Fóton , Tecido Adiposo/efeitos dos fármacos , Idoso , Antioxidantes/metabolismo , Biomarcadores , Composição Corporal/efeitos dos fármacos , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Avaliação Geriátrica , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
16.
JPEN J Parenter Enteral Nutr ; 35(6): 757-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21807930

RESUMO

BACKGROUND: Older adults supplemented for 1 year with ß-hydroxy-ß-methylbutyrate, arginine, and lysine (HMB/ARG/LYS) were previously shown to have significant gains in fat-free mass (FFM) but not muscular strength. OBJECTIVE: Recently, increasing levels of serum vitamin D have been associated with an increase in muscle function, particularly in the elderly. To determine if vitamin D status may have limited strength gain in participants supplemented with HMB/ARG/LYS, the authors performed post hoc analysis of strength based on the participants' vitamin D status. METHODS: Elderly (age 76.0 ± 1.6 years) adults were recruited for a double-blinded, controlled study and were randomly assigned to either an isonitrogenous control (n = 37) or HMB/ARG/LYS (n = 40) for the yearlong study. Participants were further segregated based on their vitamin D status of either <30 or ≥30 ng 25OH-vitD(3)/mL serum, and an analysis was performed on the 4 cohorts. RESULTS: Regardless of vitamin D status, HMB/ARG/LYS resulted in significantly increased FFM (P < .02), but only in those with vitamin D status ≥30 ng 25OH-vitD(3)/mL was there a significant increase in strength with HMB/ARG/LYS (P < .01). Control-supplemented participants, regardless of vitamin D status, and the HMB/ARG/LYS-supplemented participants with vitamin D status <30 ng 25OH-vitD(3) failed to show improvements in strength. CONCLUSIONS: The nutrient cocktail of HMB/ARG/LYS alone was effective in increasing muscle mass regardless of vitamin D status, but accompanying strength increases were observed only when participants also had adequate vitamin D status indicating a synergistic effect between the HMB/ARG/LYS and vitamin D.


Assuntos
Aminoácidos/farmacologia , Butiratos/farmacologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Aptidão Física/fisiologia , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Idoso , Arginina/farmacologia , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Estudos de Coortes , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Lisina/farmacologia , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Vitamina D/sangue , Deficiência de Vitamina D/sangue
17.
Nutr Clin Pract ; 26(4): 463-73, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21775642

RESUMO

BACKGROUND: Research in the treatment of Crohn's disease (CD) supports anti-inflammatory benefits of n-3 fatty acids from fish oil, prebiotics, and antioxidants. A nutritionally balanced inflammatory bowel disease nutrition formula (IBDNF) enriched with these compounds has the potential to improve nutrition status and disease activity in CD. METHODS: This is an open-label pilot study investigating the effects of IBDNF on nutrition status in CD patients. Twenty-eight patients with active CD on stable medication were asked to consume 16 oz of IBDNF/d for 4 months. Nutrition status was assessed with dual-energy X-ray absorptiometry scans and serum micronutrient levels. Disease activity and quality of life were measured using the Crohn's Disease Activity Index (CDAI) and the Inflammatory Bowel Disease Questionnaire (IBDQ). RESULTS: Twenty patients completed the final visit. After 4 months, there was a significant decrease in plasma phospholipid levels of arachidonic acid with increases in eicosapentaenoic acid (EPA) and docosahexaenoic acid. Ten patients had a final EPA concentration of >2%. There was improvement in fat-free and fat mass in patients with final EPA >2% (P = .014 and P = .05). Vitamin D (25-OH) levels improved in all patients (18.5-25.9 ng/mL, P < .001). Those with EPA >2% had significantly lower CDAI (116 ± 94.5 vs 261.8 ± 86.5; P = .005) and higher IBDQ (179.1 ± 26.6 vs 114.6 ± 35.9, P < .001) compared to those with EPA <2%. CONCLUSIONS: IBDNF has the potential to deposit fat-free and fat mass, improve vitamin D status, and improve quality of life in CD patients.


Assuntos
Antioxidantes/uso terapêutico , Doença de Crohn/tratamento farmacológico , Ácidos Graxos Ômega-3/uso terapêutico , Ácidos Graxos Insaturados/sangue , Óleos de Peixe/uso terapêutico , Estado Nutricional/efeitos dos fármacos , Prebióticos , Tecido Adiposo/efeitos dos fármacos , Administração Oral , Adulto , Idoso , Antioxidantes/farmacologia , Ácido Araquidônico/sangue , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Doença de Crohn/sangue , Fibras na Dieta/farmacologia , Fibras na Dieta/uso terapêutico , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/sangue , Combinação de Medicamentos , Ácido Eicosapentaenoico/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-3/farmacologia , Feminino , Óleos de Peixe/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Fosfolipídeos/química , Projetos Piloto , Índice de Gravidade de Doença , Inquéritos e Questionários , Vitamina D/análogos & derivados , Vitamina D/sangue , Adulto Jovem
18.
J Nutr Health Aging ; 14(7): 579-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20818474

RESUMO

BACKGROUND: Among various nutrients branched amino acids (BCAAS) have been shown to be the most responsible for the stimulation of protein synthesis in various situations including catabolic states. OBJECTIVES: We evaluated the effect of a small amount of proteins enriched with BCAAs (0.4 g/kg/day and 0.2 g/kg/day BCAAs) on body weight and composition; nitrogen balance, energy intake and inflammation after 2 weeks of supplementation in acute elderly with catabolic status. DESIGN: Two weeks randomized controlled trial. SETTING: Geriatric department of teaching hospital. SUBJECTS: Thirty patients with malnutrition and inflammatory process (MNA < 24, albumin < 30 g/l and CRP > or = 20 mg/l) who agreed to participate in the study were consecutively included. METHODS: Body composition was determined by labelled water dilution method; resting energy expenditure (REE) was determined by indirect calorimetry; energy intake was calculated for a 3 days period at D1 and D12. Nutritional and inflammatory proteins and cytokines (IL-6 and TNF) were measured at day 1 and 14. RESULTS: No difference was observed at day 14 between supplemented (S) and control (C) group for weight (S: 58.0 +/- 11.8 kg and C: 60.0 +/- 15.9 kg); fat free mass (S: 40.7 +/- 8.3 kg and C: 40 +/- 8.2 kg); nitrogen balance (S: 1.34 +/- 2.21 g/day and C: 0.59 +/- 4.47 g/day); and energy intake (S: 20 +/- 3.6 kcal/day and C: 20.5 +/- 8.6 kcal/day). Energy intake was at similar level than REE and clearly less than energy requirement in C and S. A significant decrease was observed for orosomucoid and Prognostic Inflammatory and Nutritional Index (PINI) in S. CONCLUSION: Our results do not confirm improvement of nutritional status with enriched BCAAs supplementation as suggested in the literature. Persistence of inflammatory condition may be an explanation despite an improvement of inflammatory status was observed in the supplemented group. Those results show clearly that energy requirements are not covered in acute hospitalized elderly people. The fact that not only energy intake but also REE are decreased brings a new insight on catabolic situations.


Assuntos
Aminoácidos/uso terapêutico , Suplementos Nutricionais , Inflamação/tratamento farmacológico , Desnutrição/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Aminoácidos/farmacologia , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Feminino , Humanos , Inflamação/complicações , Masculino , Desnutrição/complicações , Nitrogênio/sangue , Estado Nutricional/efeitos dos fármacos , Orosomucoide/metabolismo
19.
Obesity (Silver Spring) ; 18(12): 2260-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20339368

RESUMO

Oleoyl-estrone (OE) has been presented as a potential antiobesity therapeutic, but the published series of studies from one laboratory has not yet been independently confirmed, and the exact mechanism of action is unknown. Based on the hypothesis that OE has potential for the treatment of obesity, male and female rats were chronically treated with several doses of OE to evaluate the impact of this compound on energy metabolism. Body weight, body composition, energy balance parameters and the expression of hypothalamic neuropeptides regulating food intake as well as key markers of the reproductive system were examined. OE impressively reduced food consumption and body weight gain in both sexes. Although a major part of the loss in body weight could be explained by decreased fat mass, a substantial loss of lean mass also occurred after OE administration. The loss of weight can be sufficiently explained by the suppression of food consumption, as there were no major changes in energy expenditure, locomotor activity or respiratory quotient. In situ hybridization data showed no significant change in the expression of key neuropeptides and hormone receptors regulating feeding behavior after OE treatment. Cocaine-amphetamine-regulated transcript (CART) mRNA levels were decreased in the arcuate nucleus of OE-treated rats. Hypogonadism and low plasma testosterone levels were found in OE-treated males, whereas females showed substantially increased liver size. The present data suggest that OE decreases food intake and body weight but also appears to cause a significant impact on the hypothalamus-pituitary-reproductive axis.


Assuntos
Fármacos Antiobesidade/farmacologia , Ingestão de Energia/efeitos dos fármacos , Estrona/análogos & derivados , Obesidade/metabolismo , Ácidos Oleicos/farmacologia , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Animais , Fármacos Antiobesidade/uso terapêutico , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Núcleo Arqueado do Hipotálamo/metabolismo , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Estrona/farmacologia , Estrona/uso terapêutico , Feminino , Hipogonadismo/induzido quimicamente , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Hibridização In Situ , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Obesidade/tratamento farmacológico , Obesidade/patologia , Ácidos Oleicos/uso terapêutico , Tamanho do Órgão/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Testosterona/sangue
20.
Am J Physiol Regul Integr Comp Physiol ; 294(3): R1061-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18184759

RESUMO

Trout are of interest in defining the relationship between fluid and salt balance on cardiovascular function because they thrive in freshwater (FW; volume loading, salt depleting), saltwater (SW; volume depleting, salt loading), and FW while fed a high-salt diet (FW-HS; volume and salt loading). The effects of chronic (>2 wk) adaptation to these three protocols on blood volume (51Cr red cell space), extracellular fluid volume (99mTc-diethylene triaminepenta-acetic acid space), arterial (dorsal aortic; P(DA)) and venous (ductus Cuvier; Pven) blood pressure, mean circulatory filling pressure (zero-flow Pven), and vascular capacitance were examined in the present study on unanesthetized rainbow trout. Blood volume, extracellular fluid volume, P(DA), Pven, and mean circulatory filling pressure progressively increased in the order SW < FW < FW-HS. Vascular capacitance in SW fish appeared to be continuous with the capacitance curve of FW fish and reflect a passive volume-dependent unloading of the venous system of FW fish. Vascular capacitance curves for FW-HS fish were displaced upward and parallel to those of FW fish, indicative of an active increase in unstressed blood volume without any change in vascular compliance. These studies are the first in any vertebrate to measure the relationship between fluid compartments and cardiovascular function during independent manipulation of volume and salt balance, and they show that volume, but not salt, balance is the primary determinant of blood pressure in trout. They also present a new paradigm with which to investigate the relative contributions of water and salt balance in cardiovascular homeostasis.


Assuntos
Adaptação Fisiológica/fisiologia , Pressão Sanguínea/fisiologia , Compartimentos de Líquidos Corporais/fisiologia , Água Doce , Oncorhynchus mykiss/fisiologia , Água do Mar , Cloreto de Sódio na Dieta/farmacologia , Capacitância Vascular/fisiologia , Animais , Aorta Torácica/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Volume Sanguíneo/fisiologia , Compartimentos de Líquidos Corporais/efeitos dos fármacos , Dieta , Homeostase/fisiologia , Capacitância Vascular/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/fisiologia
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