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1.
Am J Physiol Cell Physiol ; 326(6): C1769-C1775, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38682238

RESUMO

We recently demonstrated that acute oral ketone monoester intake induces a stimulation of postprandial myofibrillar protein synthesis rates comparable to that elicited following the ingestion of 10 g whey protein or their coingestion. The present investigation aimed to determine the acute effects of ingesting a ketone monoester, whey protein, or their coingestion on mechanistic target of rapamycin (mTOR)-related protein-protein colocalization and intracellular trafficking in human skeletal muscle. In a randomized, double-blind, parallel group design, 36 healthy recreationally active young males (age: 24.2 ± 4.1 yr) ingested either: 1) 0.36 g·kg-1 bodyweight of the ketone monoester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KET), 2) 10 g whey protein (PRO), or 3) the combination of both (KET + PRO). Muscle biopsies were obtained in the overnight postabsorptive state (basal conditions), and at 120 and 300 min in the postprandial period for immunofluorescence assessment of protein translocation and colocalization of mTOR-related signaling molecules. All treatments resulted in a significant (Interaction: P < 0.0001) decrease in tuberous sclerosis complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) colocalization at 120 min versus basal; however, the decrease was sustained at 300 min versus basal (P < 0.0001) only in KET + PRO. PRO and KET + PRO increased (Interaction: P < 0.0001) mTOR-Rheb colocalization at 120 min versus basal; however, KET + PRO resulted in a sustained increase in mTOR-Rheb colocalization at 300 min that was greater than KET and PRO. Treatment intake increased mTOR-wheat germ agglutinin (WGA) colocalization at 120 and 300 min (Time: P = 0.0031), suggesting translocation toward the fiber periphery. These findings demonstrate that ketone monoester intake can influence the spatial mechanisms involved in the regulation of mTORC1 in human skeletal muscle.NEW & NOTEWORTHY We explored the effects of a ketone monoester (KET), whey protein (PRO), or their coingestion (KET + PRO) on mTOR-related protein-protein colocalization and intracellular trafficking in human muscle. All treatments decreased TSC2-Rheb colocalization at 120 minutes; however, KET + PRO sustained the decrease at 300 min. Only PRO and KET + PRO increased mTOR-Rheb colocalization; however, the increase at 300 min was greater in KET + PRO. Treatment intake increased mTOR-WGA colocalization, suggesting translocation to the fiber periphery. Ketone bodies influence the spatial regulation of mTOR.


Assuntos
Músculo Esquelético , Transporte Proteico , Serina-Treonina Quinases TOR , Proteínas do Soro do Leite , Humanos , Proteínas do Soro do Leite/metabolismo , Proteínas do Soro do Leite/farmacologia , Proteínas do Soro do Leite/administração & dosagem , Masculino , Serina-Treonina Quinases TOR/metabolismo , Adulto Jovem , Adulto , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Método Duplo-Cego , Ácido 3-Hidroxibutírico/farmacologia , Ácido 3-Hidroxibutírico/metabolismo , Período Pós-Prandial , Cetonas/metabolismo , Proteínas Musculares/metabolismo
2.
J Nutr ; 154(7): 2143-2156, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703891

RESUMO

BACKGROUND: ß-casein is the main casein constituent in human milk (HM) and a source of bioactive peptides for the developing gastrointestinal tract and immune system. Infant formulas contain less ß-casein than HM, but whether different concentrations of ß-casein affect tolerability and gut and immune maturation in newborns is unknown. OBJECTIVES: Using near-term piglets as a model for newborn infants, we investigated whether increasing the ß-casein fraction in bovine-based formula is clinically safe and may improve gut and immune maturation. METHODS: Three groups of near-term pigs (96% gestation) were fed formula with bovine casein and whey protein (ratio 40:60): 1) standard skim milk casein (BCN-standard, 35% ß-casein of total casein, n = 18); 2) ß-casein enrichment to HM concentrations (BCN-medium, 65%, n = 19); and 3) high ß-casein enrichment (BCN-high, 91%, n = 19). A reference group was fed 100% whey protein concentrate (WPC) as protein (WPC, n = 18). Intestinal and immune parameters were assessed before and after euthanasia on day 5. RESULTS: Clinical variables (mortality, activity, body growth, and diarrhea) were similar among the groups, and no differences in intestinal or biochemical parameters were observed between BCN-standard and BCN-medium pigs. However, pigs receiving high amounts of ß-casein (BCN-high) had lower small intestine weight and tended to have more intestinal complications (highest gut pathology score, permeability, and interleukin-8) than the other groups, particularly those receiving no casein (WPC pigs). Blood lymphocyte, thrombocyte, and reticulocyte counts were increased with higher ß-casein, whereas eosinophil counts were reduced. In vitro blood immune cell responses were similar among groups. CONCLUSIONS: ß-casein enrichment of bovine-based formula to HM concentrations is clinically safe, as judged from newborn, near-term pigs, whereas no additional benefits to gut maturation were observed. However, excessive ß-casein supplementation, beyond concentrations in HM, may potentially induce gut inflammation together with increased blood cell populations relative to natural ß-casein concentrations or pure whey-based formula.


Assuntos
Animais Recém-Nascidos , Caseínas , Proteínas do Soro do Leite , Animais , Caseínas/administração & dosagem , Suínos , Proteínas do Soro do Leite/administração & dosagem , Bovinos , Trato Gastrointestinal/efeitos dos fármacos , Fórmulas Infantis , Leite/química
3.
J Nutr ; 154(6): 1766-1780, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583524

RESUMO

BACKGROUND: A balanced intake of protein and constituent amino acids (AAs) requires adjustments to total food intake (protein leverage [PL]) and food selection to balance deficits and excesses (complementary feeding). We provided mice with choices of casein and whey, 2 protein sources that are complementary in AA balance, across a range of protein concentrations (P%) of digestible energy (DE). OBJECTIVES: We aimed to determine if: 1) PL operates similarly for casein and whey; 2) one protein source is preferred at control P%; 3) the preference changes as P% falls; and 4) AA intakes under control and low P% levels identify AAs that drive changes in protein selection. METHODS: Food intake and plasma fibroblast growth factor-21 (FGF21) concentrations were measured in mice at various P% (P7.5%-P33%). For direct comparisons, defined diets were used in which the protein source was either casein or whey. In food choice studies, mice had access to foods in which both casein and whey were provided at the same P% level at the same time. RESULTS: PL operated at different P% thresholds in casein (13%)- and whey (10%)-based diets, and the magnitude of PL was greater for casein. Although mice preferred casein under control conditions (P23%), a pronounced preference shift to whey occurred as P% fell to P13% and P10%. At low P%, increases in food intake were accompanied by increases in plasma FGF21, a protein hunger signal. Among AAs deficient in casein and enriched in whey, the intake of Cys was the most invariant as P% changed between P23% and P10%, appearing to drive the switch in protein preference. CONCLUSIONS: Mice selected between complementary protein sources, casein and whey, achieving stable total energy intake and regulated intake of AAs as P% varied. Supplementation of low P% casein diets with one whey-enriched AA, Cys, suppressed plasma FGF21 and total food intake.


Assuntos
Aminoácidos , Caseínas , Proteínas Alimentares , Ingestão de Energia , Fatores de Crescimento de Fibroblastos , Animais , Camundongos , Aminoácidos/sangue , Aminoácidos/metabolismo , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/farmacologia , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/sangue , Caseínas/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Preferências Alimentares , Proteínas do Soro do Leite/administração & dosagem , Dieta
4.
Eur J Appl Physiol ; 124(7): 2045-2056, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38386104

RESUMO

PURPOSE: Intestinal permeability is a critical component of gut barrier function. Barrier dysfunction can be triggered by certain stressors such as exercise, and if left unmanaged can lead to local and systemic disorders. The aim of this study was to investigate the effects of a specific whey protein fraction in alleviating exercise-induced gut permeability as assessed by recovery of lactulose/rhamnose (L/R) and lactulose/mannitol (L/M) urinary probes. METHODS: Eight males and eight females (aged 18-50) completed two arms of a double-blind, placebo-controlled, crossover study. For each arm participants performed two baseline intestinal permeability assessments, following which they consumed the treatment (2 g/day of milk powder containing 200 mg of whey protein) or placebo (2 g/day of milk powder) for 14 days, before performing a post-exercise permeability assessment. The exercise protocol involved a 20-min run at 80% of maximal oxygen uptake on a 1% incline. RESULTS: Mixed model analysis revealed an increase in L/R (23%; P < 0.001) and L/M (20%; P < 0.01) recovery following exercise. However, there was no treatment or treatment × exercise effect. CONCLUSION: The exercise protocol utilised in our study induces gut permeability. However, consuming whey protein, at the dose and timing prescribed, is not able to mitigate this effect.


Assuntos
Exercício Físico , Permeabilidade , Proteínas do Soro do Leite , Humanos , Proteínas do Soro do Leite/farmacologia , Proteínas do Soro do Leite/administração & dosagem , Masculino , Adulto , Feminino , Exercício Físico/fisiologia , Permeabilidade/efeitos dos fármacos , Animais , Método Duplo-Cego , Pessoa de Meia-Idade , Adulto Jovem , Lactulose/urina , Lactulose/farmacologia , Estudos Cross-Over , Adolescente , Bovinos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Ramnose/farmacologia , Manitol/farmacologia
5.
Appetite ; 200: 107509, 2024 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795943

RESUMO

Glycomacropeptide (GMP) has a unique amino acid profile which may make less satiating than other dietary proteins. This study assessed the feasibility and likely acceptability of a leucine-enriched GMP drink and determined appetite response in older adults (OA). Thirteen OA (11f; 70 ± 4 years) were recruited for sensory assessments of a leucine-enriched GMP drink when mixed with water and with fruit smoothie, compared with whey protein isolate (WHEY). Participants also partook in a single focus group exploring acceptability to protein and supplementation. Separately, a counterbalanced, double-blind study with twelve OA (8f; 69 ± 3 years) was conducted to determine appetite and gut hormone responses. Fasting subjective appetite was recorded using visual analogue scales and a fasted venous blood sample was collected (to measures acyl-ghrelin, PYY, GLP-1, and CCK) before participants consumed either: GMP protein (27g + 3g leucine, 350 mL water), WHEY (30g, 350 mL water), or water. Participants rested for 240 min, with appetite measures and blood sampling throughout. An ad libitum pasta-based meal was then consumed. Sensory testing revealed low pleasantness rating for GMP in water vs. WHEY (16 ± 14 vs 31 ± 24, p = 0.016). GMP addition to smoothie reduced pleasantness (26 ± 21 vs. 61 ± 29, p = 0.009) and worsened the aroma (46 ± 15 vs. 69 ± 28, p = 0.014). The focus group revealed uncertainty of protein needs and a scepticism of supplements, with preference for food. Gut hormone response did not differ between GMP and WHEY (nAUC for all gut hormones p > 0.05). There was no difference between conditions for lunch ad libitum intake (549 ± 171 kcal, 512 ± 238 kcal, 460 ± 199 kcal for GMP, WHEY, and water, p = 0.175), or for subjective appetite response. Leucine-enriched GMP was not less satiating than WHEY, and low palatability and scepticism of supplements question the likely acceptability of GMP supplementation. Providing trusted nutritional advice and food enrichment/fortification may be preferred strategies for increasing protein intake in OA.


Assuntos
Apetite , Caseínas , Estudos de Viabilidade , Hormônios Gastrointestinais , Fragmentos de Peptídeos , Proteínas do Soro do Leite , Humanos , Feminino , Masculino , Apetite/efeitos dos fármacos , Idoso , Projetos Piloto , Hormônios Gastrointestinais/sangue , Método Duplo-Cego , Caseínas/administração & dosagem , Caseínas/farmacologia , Proteínas do Soro do Leite/administração & dosagem , Proteínas do Soro do Leite/farmacologia , Fragmentos de Peptídeos/sangue , Leucina/administração & dosagem , Leucina/farmacologia , Grelina/sangue , Saciação/efeitos dos fármacos , Ingestão de Alimentos , Suplementos Nutricionais , Pessoa de Meia-Idade , Peptídeo YY/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Proteínas Alimentares/administração & dosagem
6.
Int J Sport Nutr Exerc Metab ; 34(4): 189-198, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604602

RESUMO

Whey protein ingestion during recovery from exercise increases myofibrillar but not muscle connective protein synthesis rates. It has been speculated that whey protein does not provide sufficient glycine to maximize postexercise muscle connective protein synthesis rates. In the present study, we assessed the impact of coingesting different amounts of collagen with whey protein as a nutritional strategy to increase plasma glycine availability during recovery from exercise. In a randomized, double-blind, crossover design, 14 recreationally active men (age: 26 ± 5 years; body mass index: 23.8 ± 2.1 kg·m-2) ingested in total 30 g protein, provided as whey protein with 0 g (WHEY), 5 g (WC05); 10 g (WC10), and 15 g (WC15) of collagen protein immediately after a single bout of resistance exercise. Blood samples were collected frequently over 6 hr of postexercise recovery to assess postprandial plasma amino acid kinetics and availability. Protein ingestion strongly increased plasma amino acid concentrations (p < .001) with no differences in plasma total amino acid availability between treatments (p > .05). The postprandial rise in plasma leucine and essential amino acid availability was greater in WHEY compared with the WC10 and WC15 treatments (p < .05). Plasma glycine and nonessential amino acid concentrations declined following whey protein ingestion but increased following collagen coingestion (p < .05). Postprandial plasma glycine availability averaged -8.9 ± 5.8, 9.2 ± 3.7, 23.1 ± 6.5, and 39.8 ± 11.0 mmol·360 min/L in WHEY, WC05, WC10, and WC15, respectively (incremental area under curve values, p < .05). Coingestion of a small amount of collagen (5 g) with whey protein (25 g) is sufficient to prevent the decline in plasma glycine availability during recovery from lower body resistance-type exercise in recreationally active men.


Assuntos
Colágeno , Estudos Cross-Over , Glicina , Proteínas do Soro do Leite , Humanos , Proteínas do Soro do Leite/administração & dosagem , Masculino , Adulto , Glicina/sangue , Glicina/administração & dosagem , Método Duplo-Cego , Adulto Jovem , Período Pós-Prandial , Exercício Físico/fisiologia , Treinamento Resistido , Fenômenos Fisiológicos da Nutrição Esportiva , Aminoácidos/sangue , Aminoácidos/administração & dosagem , Músculo Esquelético/metabolismo
7.
Am J Physiol Endocrinol Metab ; 321(6): E802-E820, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747202

RESUMO

Sprint interval training (SIT) is a time-efficient alternative to endurance exercise, conferring beneficial skeletal muscle metabolic adaptations. Current literature has investigated the nutritional regulation of acute and chronic exercise-induced metabolic adaptations in muscle following endurance exercise, principally comparing the impact of training in fasted and carbohydrate-fed (CHO) conditions. Alternative strategies such as exercising in low CHO, protein-fed conditions remain poorly characterized, specifically pertaining to adaptations associated with SIT. Thus, this study aimed to compare the metabolic and performance adaptations to acute and short-term SIT in the fasted state with preexercise hydrolyzed (WPH) or concentrated (WPC) whey protein supplementation. In healthy males, preexercise protein ingestion did not alter exercise-induced increases in PGC-1α, PDK4, SIRT1, and PPAR-δ mRNA expression following acute SIT. However, supplementation of WPH beneficially altered acute exercise-induced CD36 mRNA expression. Preexercise protein ingestion attenuated acute exercise-induced increases in muscle pan-acetylation and PARP1 protein content compared with fasted SIT. Acute serum metabolomic differences confirmed greater preexercise amino acid delivery in protein-fed compared with fasted conditions. Following 3 wk of SIT, training-induced increases in mitochondrial enzymatic activity and exercise performance were similar across nutritional groups. Interestingly, resting muscle acetylation status was downregulated in WPH conditions following training. Such findings suggest preexercise WPC and WPH ingestion positively influences metabolic adaptations to SIT compared with fasted training, resulting in either similar or enhanced performance adaptations. Future studies investigating nutritional modulation of metabolic adaptations to exercise are warranted to build upon these novel findings.NEW & NOTEWORTHY These are the first data to show the influence of preexercise protein on serum and skeletal muscle metabolic adaptations to acute and short-term sprint interval training (SIT). Preexercise whey protein concentrate (WPC) or hydrolysate (WPH) feeding acutely affected the serum metabolome, which differentially influenced acute and chronic changes in mitochondrial gene expression, intracellular signaling (acetylation and PARylation) resulting in either similar or enhanced performance outcomes when compared with fasted training.


Assuntos
Adaptação Fisiológica , Jejum/fisiologia , Treinamento Intervalado de Alta Intensidade , Resistência Física , Proteínas do Soro do Leite/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Adolescente , Adulto , Análise Química do Sangue , Suplementos Nutricionais , Método Duplo-Cego , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Masculino , Metaboloma/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Resistência Física/efeitos dos fármacos , Resistência Física/genética , Corrida , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcriptoma/efeitos dos fármacos , Proteínas do Soro do Leite/administração & dosagem , Adulto Jovem
8.
J Nutr ; 151(6): 1462-1472, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33693737

RESUMO

BACKGROUND: Muscle loss during acute infectious disease is mainly triggered by inflammation, immobilization, and malnutrition. OBJECTIVE: The objective was to compare muscle protein kinetics and metabolism following ingestion of the dairy protein supplements ß-lactoglobulin (BLG), casein (CAS), and whey (WHE) during controlled catabolic conditions. METHODS: We used a randomized crossover design (registered at clinicaltrials.gov as NCT03319550) to investigate 9 healthy male participants [age: 20-40 y; BMI (in kg/m2) 20-30] who were randomly assigned servings of BLG, CAS, or WHE (0.6 g protein/kg, one-third as bolus and two-thirds as sip every 20 min) on 3 separate occasions separated by ∼6-8 wk. The participants received an infusion of lipopolysaccharide (1 ng/kg) combined with 36 h of fasting and bed rest before each study day, mimicking a clinical catabolic condition. The forearm model and isotopic tracer techniques were used to quantify muscle protein kinetics. Muscle biopsy specimens were obtained and intramyocellular signaling investigated using Western blot. RESULTS: BLG, CAS, and WHE improved the net balance of phenylalanine (NBphe) from baseline with ∼75% (P < 0.001) with no difference between interventions (primary outcome, P < 0.05). No difference in rates of appearance and disappearance of phenylalanine or in intramyocellular signaling activation was found between interventions (secondary outcomes). The incremental AUC for serum insulin was 62% higher following BLG compared with CAS (P < 0.001) and 30% higher compared with WHE (P = 0.002), as well as 25% higher in WHE compared with CAS (P = 0.006). Following BLG consumption, plasma concentrations of glucose-dependent insulinotropic peptide (GIP) increased 70% compared with CAS (P = 0.001) and increased 34% compared with WHE (P = 0.06). No significant difference was found between WHE and CAS (P = 0.12). CONCLUSION: BLG, WHE, and CAS have similar effects on muscle in young male participants during catabolic conditions. BLG showed specific, possibly GIP-dependent, insulinotropic properties, which may have future clinical implications.


Assuntos
Caseínas , Lactoglobulinas , Proteínas Musculares/metabolismo , Proteínas do Soro do Leite , Adulto , Caseínas/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Polipeptídeo Inibidor Gástrico/sangue , Humanos , Lactoglobulinas/administração & dosagem , Masculino , Fenilalanina/metabolismo , Proteínas do Soro do Leite/administração & dosagem , Adulto Jovem
9.
Br J Nutr ; 125(6): 669-677, 2021 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-32713395

RESUMO

Poor post-prandial glucose control is a risk factor for multiple health conditions. The second-meal effect refers to the progressively improved glycaemic control with repeated feedings, an effect which is achievable with protein ingestion at the initial eating occasion. The most pronounced glycaemic response each day therefore typically occurs following breakfast, so the present study investigated whether ingesting protein during the night could improve glucose control at the first meal of the day. In a randomised crossover design, fifteen adults (seven males, eight females; age, 22 (sd 3) years; BMI, 24·0 (sd 2·8) kg/m2; fasting blood glucose, 4·9 (sd 0·5) mmol/l) woke at 04.00 (sd 1) hours to ingest 300 ml water with or without 63 g whey protein. Participants then completed a mixed-macronutrient meal tolerance test (1 g carbohydrate/kg body mass, 2356 (sd 435) kJ), 5 h 39 min following the nocturnal feeding. Nocturnal protein ingestion increased the glycaemic response (incremental AUC) to breakfast by 43·5 (sd 55·5) mmol × 120 min/l (P = 0·009, d = 0·94). Consistent with this effect, individual peak blood glucose concentrations were 0·6 (sd 1·0) mmol/l higher following breakfast when protein had been ingested (P = 0·049, d = 0·50). Immediately prior to breakfast, rates of lipid oxidation were 0·02 (sd 0·03) g/min higher (P = 0·045) in the protein condition, followed by an elevated post-prandial energy expenditure (0·38 (sd 0·50) kJ/min, P = 0·018). Post-prandial appetite and energy intake were similar between conditions. The present study reveals a paradoxical second-meal phenomenon whereby nocturnal whey protein feeding impaired subsequent glucose tolerance, whilst increasing post-prandial energy expenditure.


Assuntos
Glicemia/análise , Desjejum , Ingestão de Alimentos , Período Pós-Prandial , Proteínas do Soro do Leite/administração & dosagem , Apetite , Estudos Cross-Over , Ingestão de Energia , Metabolismo Energético , Feminino , Controle Glicêmico , Humanos , Masculino , Sono , Adulto Jovem
10.
Br J Nutr ; 125(9): 1017-1033, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32498755

RESUMO

Ageing leads to a progressive loss of muscle function (MF) and quality (MQ: muscle strength (MS)/lean muscle mass (LM)). Power training and protein (PROT) supplementation have been proposed as efficient interventions to improve MF and MQ. Discrepancies between results appear to be mainly related to the type and/or dose of proteins used. The present study aimed at determining whether or not mixed power training (MPT) combined with fast-digested PROT (F-PROT) leads to greater improvements in MF and MQ in elderly men than MPT combined with slow-digested PROT (S-PROT) or MPT alone. Sixty elderly men (age 69 (sd 7) years; BMI 18-30 kg/m2) were randomised into three groups: (1) placebo + MPT (PLA; n 19); (2) F-PROT + MPT (n 21) and (3) S-PROT + MPT (n 20) completed the intervention. LM, handgrip and knee extensor MS and MQ, functional capacity, serum metabolic markers, skeletal muscle characteristics, dietary intake and total energy expenditure were measured. The interventions consisted in 12 weeks of MPT (3 times/week; 1 h/session) combined with a supplement (30 g:10 g per meal) of F-PROT (whey) or S-PROT (casein) or a placebo. No difference was observed among groups for age, BMI, number of steps and dietary intake pre- and post-intervention. All groups improved significantly their LM, lower limb MS/MQ, functional capacity, muscle characteristics and serum parameters following the MPT. Importantly, no difference between groups was observed following the MPT. Altogether, adding 30 g PROT/d to MPT, regardless of the type, does not provide additional benefits to MPT alone in older men ingesting an adequate (i.e. above RDA) amount of protein per d.


Assuntos
Suplementos Nutricionais , Proteínas do Leite/administração & dosagem , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido , Idoso , Envelhecimento , Digestão , Força da Mão , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Desempenho Físico Funcional , Proteínas do Soro do Leite/administração & dosagem
11.
Gynecol Endocrinol ; 37(8): 753-757, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34060419

RESUMO

AIMS: To investigate the change of stress hormones, oxidative stress and insulin resistance (IR) in women with gestational diabetes mellitus (GDM) after supplement whey protein, in an attempt to gain insights into the prevention and treatment of GDM. MATERIALS AND METHODS: 60 GDM women were recruited in this study, and 30 women received a preload drink containing 20 g whey protein as group GDM-W, and the other 30 women received control flavoring drink as group GDM, and the trial lasted for 14 days. Plasma epinephrine (E), noradrenaline (NE), and cortisol were detected; we also determined levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH). Homeostasis model assessment of insulin resistance (HOMA-IR) was used to assess IR. RESULTS: In the GDM-W group, postprandial blood glucose was decreased significantly on 3, 5, 7, and 14 days (all p < .05), plasma 2 h insulin was increased by 7.2, 8.6, and 20.5% on days 5, 7, and 14 (p < .05, .05, .01). HOMA-IR was decreased significantly on day 14 (p < .05). MDA was decreased by 20.7% on day 14 (p < .01), and anti-oxidative enzymes' SOD was decreased by 13.4% on day 14 (p < .05) and GSH was decreased by 16.7 and 29.1% on days 7 and 14 (both p < .05). Stress hormones E and cortisol were decreased by 10.8 and 19.8%, respectively, on day 14 (p < .05). There was no significant difference in NE between the two groups within 14 days. CONCLUSIONS: Whey protein supplementation may improve hyperglycemia by alleviating stress disorder and oxidative stress injury in GDM women. This trial was registered at chictr.org.cn/as ChiCTR1800020413.


Assuntos
Catecolaminas/sangue , Diabetes Gestacional/dietoterapia , Hidrocortisona/sangue , Hiperglicemia/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Proteínas do Soro do Leite/administração & dosagem , Adulto , Glicemia/análise , Diabetes Gestacional/sangue , Diabetes Gestacional/fisiopatologia , Epinefrina/sangue , Feminino , Idade Gestacional , Glutationa/sangue , Humanos , Resistência à Insulina , Malondialdeído/sangue , Norepinefrina/sangue , Gravidez , Superóxido Dismutase/sangue
12.
Int J Sports Med ; 42(3): 259-263, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33063309

RESUMO

The purpose was to compare the effects of protein (whey protein) and carbohydrate supplementation and protein alone both combined with resistance training on muscle strength, muscle mass and total training volume progression in untrained young men. Resistance training was performed using the leg press and knee extension until concentric failure (8-12 repetition maximum), three times a week for eight weeks. Muscle strength and muscle cross-sectional area were assessed before and after training. Total training volume progression was calculated considering the first and eighth week. Seventeen men completed the study (protein and carbohydrate, n=9, age 23.44 ± 4.56 years, weight: 62.13±6.17 kg, height: 1.75±0.02 m, body mass index: 20.29±2.08 kg/m2; protein, n=8, age 24.63±2.39 years, weight: 69.01±5.57 kg, height: 1.77±0.07 m; body mass index: 21.64±1.05 kg/m2. Both protocols showed similar increases in muscle strength (effect size: protein and carbohydrate=1.28; protein=0.97; p<0.001), muscle cross sectional area (effect size: protein and carbohydrate=0.66; protein=0.47; p<0.001) and total training volume progression (effect size: protein and carbohydrate=2.68; protein=1.63; p<0.001) after training. No differences were found between groups p>0.05). Protein and carbohydrate supplementation combined with resistance training does not induce greater gains in muscle strength, hypertrophy and total training volume compared to resistance training combined with protein alone in untrained individuals.


Assuntos
Adaptação Fisiológica , Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Proteínas do Soro do Leite/administração & dosagem , Adolescente , Adulto , Humanos , Joelho/fisiologia , Perna (Membro)/fisiologia , Masculino , Força Muscular , Músculo Esquelético/anatomia & histologia , Aumento do Músculo Esquelético , Adulto Jovem
13.
J Sports Sci ; 39(3): 322-331, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33012216

RESUMO

The current double blind, randomized, placebo-controlled trial with two parallel groups aimed to assess the impact of whey protein supplementation on recovery of muscle function and muscle soreness following eccentric exercise. During a 9-day period, forty recreationally active males received twice daily supplementation with either whey protein (PRO; 60 g/day) or an iso-energetic amount of carbohydrate (CON). Muscle function and soreness were assessed before, and 0, 3, 24, 48, and 72 h after performing 100 drop jumps. Recovery of isometric maximal voluntary contraction (MVC) did not significantly differ between groups (timextreatment, P = 0.56). In contrast, the recovery of isokinetic MVC at 90°·s-1 was faster in CON as opposed to PRO (timextreatment interaction, P = 0.044). Recovery of isokinetic MVC at 180°·s-1 was also faster in CON as opposed to PRO (timextreatment interaction, P = 0.011). Recovery of countermovement jump performance did not differ between groups (timextreatment interaction, P = 0.52). Muscle soreness, CK and CRP showed a transient increase over time (P < 0.001), with no differences between groups. In conclusion, whey protein supplementation does not accelerate recovery of muscle function or attenuate muscle soreness and inflammation during 3 days of recovery from a single bout of eccentric exercise.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Músculo Esquelético/lesões , Músculo Esquelético/fisiologia , Mialgia/prevenção & controle , Proteínas do Soro do Leite/administração & dosagem , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Creatina Quinase/sangue , Carboidratos da Dieta/administração & dosagem , Método Duplo-Cego , Humanos , Hidrocortisona/sangue , Inflamação/sangue , Joelho/fisiologia , Masculino , Contração Muscular , Adulto Jovem
14.
J Aging Phys Act ; 29(1): 17-26, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32604068

RESUMO

The purpose of this trial was to examine the effects of self-selected exercise intensities plus either whey protein or placebo supplementation on vital signs, body composition, bone mineral density, muscle strength, and mobility in older adults. A total of 101 participants aged 55 years and older (males [n = 34] and females [n = 67]) were evaluated before and after 12 weeks of self-selected, free-weight resistance exercise plus 30 min of self-paced walking three times per week. The participants were randomized into two groups: whey protein (n = 46) or placebo (n = 55). Three-way mixed factorial analyses of variance were used to test for mean differences for each variable. The 12 weeks of self-selected, self-paced exercise intensities improved resting heart rate, fat-free mass, percent body fat, handgrip strength, bench press strength, leg press strength, and all mobility measurements (p < .05) in males and females despite supplementation status. This suggests that additional protein in well-fed healthy older adults does not enhance the benefit of exercise.


Assuntos
Composição Corporal , Exercício Físico/fisiologia , Força da Mão , Músculo Esquelético/metabolismo , Treinamento Resistido , Proteínas do Soro do Leite/administração & dosagem , Idoso , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Força Muscular , Aptidão Física
15.
Turk J Med Sci ; 51(4): 2213-2221, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-33984891

RESUMO

Background/aim: We aimed to investigate whether there was a significant difference in TSH, T3, T4 values and histopathologically evaluated thyroid tissues between rats that received isole hydrolyzed whey protein (IHWP) at different doses regularly and rats fed with only standard feed. Material & methods: Total 24 rats were randomly divided into three groups with 8 rats in each group. First group were fed with standard feed for 12 weeks. Second group were given standard feed + daily 0.3 g/kg IHWP and rats in the third group standard feed + 0.5 g/kg IHWP for 12 weeks. Blood samples were collected from all rats before and after IHWP administration. All rats were then sacrificed, and thyroid tissues were histopathologically examined. Results: Interfollicular connective tissue areas and TSH (0.35­4.90 µIU/L) were higher in the control group compared to 3 cc IHWP and 5 cc IHWP groups, while thyroid hormone T4 (0.7­1.48 ng/dL), and thyroid hormone synthesis parameters including intrafollicular colloid amount, follicular diameter, and epithelial height were significantly higher in 3 cc and 5 cc IHWP groups compared to the control. Conclusion: We think that regular daily use of IHWP may increase the synthesis of thyroid hormone due to its high amino acid content.


Assuntos
Hipertireoidismo , Hipotireoidismo , Glândula Tireoide/efeitos dos fármacos , Proteínas do Soro do Leite/administração & dosagem , Animais , Ratos , Hormônios Tireóideos/sangue , Tireotropina , Tiroxina , Soro do Leite
16.
J Nutr ; 150(4): 763-774, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31879775

RESUMO

BACKGROUND: Whey protein (WH)-enriched diets are reported to aid in weight loss and to improve cardiovascular health. However, the bioactive components in whey responsible for causing such effects remain unidentified. OBJECTIVE: We determined the effects of whey and its components [α-lactalbumin (LA) and lactoferrin (LF)] on energy balance, glucose tolerance, gut hormones, renal damage, and stroke onset in rats. METHODS: Male spontaneously hypertensive stroke-prone (SHRSP) rats (age 8 wk) were fed isocaloric high-fat (40% kcal) and high-salt (4% wt/wt) diets (n = 8-10/group) and randomized for 8 wk to diets enriched as follows: control (CO): 15% kcal from egg albumin, 45% kcal from carbohydrate; WH: 20%kcal WH isolate + 15% kcal egg albumin; LA: 20% kcal LA  + 15% kcal egg albumin; or LF: 20% kcal lactoferrin + 15% kcal egg albumin. Measurements included energy balance (food intake, energy expenditure, and body composition), stroke-related behaviors, brain imaging, glucose tolerance, metabolic hormones, and tissue markers of renal damage. Data were analyzed by linear mixed models with repeated measures or 1-way ANOVA. RESULTS: Diets enriched with WH, LA, or LF increased survival, with 25% of rats fed these diets exhibiting stroke-associated morbidity, whereas 90% of CO rats were morbid by 8 wk (P < 0.05). The nephritis scores of rats fed WH-, LA-, or LF-enriched diets were 80%, 92%, and 122% lower than those of COs (P = 0.001). The mRNA abundances of renin and osteopontin were 100-600% lower in rats fed WH-, LA-, or LF-enriched diets than in COs (P < 0.05). Urine albumin concentrations and albumin-to-creatinine ratios were 200% lower in rats fed LF-enriched diets than in COs (P < 0.05). Compared with COs, rats fed LF-enriched diets for 2-3 wk had food intake decreased by 29%, body weight decreased by 13-19%, lean mass decreased by 12-19%, and fat mass decreased by 20% (P < 0.001). Relative to COs, rats fed WH and LA had food intake decreased by 10% (P < 0.1), but COs had 12-45% lower weight than rats fed LA- and WH-enriched diets by 3 wk (P < 0.01). Compared with COs, rats fed WH-enriched diets increased energy expenditure by 7%, whereas, rats fed LA-enriched diets had energy expenditure acutely decreased by 7% during the first 4 d, and rats fed LF-enriched diets had energy expenditure decreased by 7-17% throughout the first week ( P < 0.001). Rats fed LA- and LF-enriched diets had blood glucose decreased by 14-19% (P < 0.05) and WH by 9% (P = 0.1), relative to COs. Compared with COs, rats fed LF had GIP decreased by 90% and PYY by 87% (P < 0.05). CONCLUSION: Together, these findings indicate that whey and its components α-lactalbumin and lactoferrin improved energy balance and glycemic control, and protected against the onset of neurological deficits associated with stroke and renal damage in male SHRSP rats.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Nefropatias/prevenção & controle , Lactalbumina/administração & dosagem , Lactoferrina/administração & dosagem , Acidente Vascular Cerebral/prevenção & controle , Proteínas do Soro do Leite/administração & dosagem , Animais , Comportamento Animal , Glicemia/análise , Encéfalo/patologia , Encéfalo/fisiopatologia , Dieta , Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos , Nefropatias/etiologia , Nefropatias/patologia , Masculino , Atividade Motora , Ratos , Ratos Endogâmicos SHR , Cloreto de Sódio na Dieta/efeitos adversos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/patologia
17.
Nutr Cancer ; 72(3): 439-450, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31290697

RESUMO

Background: This pilot, double-blind, comparator-controlled trial evaluated the safety and tolerability of an oral targeted medical nutrition (TMN) supplement for the management of cachexia in patients with non-small-cell lung cancer (NSCLC).Methods: Patients receiving first-line chemotherapy for NSCLC with weight loss or low BMI were randomized 1:1 to receive juice-based TMN (∼200 kcal; 10 g whey protein; ≥2.0 g eicosapentaenoic acid/docosahexaenoic acid in fish oil; and 10 µg 25-hydroxy-vitamin D3) or a milk-based isocaloric comparator twice daily for 12 weeks (ClinicalTrials.gov: NCT02515032). Primary endpoints included number/type of adverse events and changes in vital signs/laboratory parameters. Secondary endpoints included measures of clinical relevance. Survival was an exploratory endpoint.Results: The TMN group (n = 26; mean 64.4 years) experienced fewer adverse events (64 vs. 87) than the comparator group (n = 29; mean 66.0 years), including fewer cases of neutropenia (0 vs. 4). Compliance was slightly lower in the TMN (58.5%) vs. comparator group (73.6%). There were no statistically significant between-group differences in efficacy endpoints. Fewer (4 vs. 10) patients who received TMN than comparator had died by 1-year post baseline.Conclusions: TMN was well tolerated. Trends for improved clinical outcomes with TMN identified in this study warrant further investigation.


Assuntos
Caquexia/dietoterapia , Carcinoma Pulmonar de Células não Pequenas/complicações , Suplementos Nutricionais/estatística & dados numéricos , Neoplasias Pulmonares/complicações , Idoso , Antineoplásicos/uso terapêutico , Peso Corporal/efeitos dos fármacos , Caquexia/complicações , Calcifediol/administração & dosagem , Calcifediol/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Suplementos Nutricionais/efeitos adversos , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácidos Docosa-Hexaenoicos/efeitos adversos , Método Duplo-Cego , Ácido Eicosapentaenoico/administração & dosagem , Ácido Eicosapentaenoico/efeitos adversos , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Neutropenia/complicações , Projetos Piloto , Resultado do Tratamento , Redução de Peso , Proteínas do Soro do Leite/administração & dosagem , Proteínas do Soro do Leite/efeitos adversos
18.
Anesth Analg ; 131(3): 840-849, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31348053

RESUMO

BACKGROUND: Patients with lung cancer often experience reduced functional capacity and quality of life after surgery. The current study investigated the impact of a short-term, home-based, multimodal prehabilitation program on perioperative functional capacity in patients undergoing video-assisted thoracoscopic surgery (VATS) lobectomy for nonsmall cell lung cancer (NSCLC). METHODS: A randomized controlled trial was conducted with 73 patients. Patients in the prehabilitation group (n = 37) received a 2-week multimodal intervention program before surgery, including aerobic and resistance exercises, respiratory training, nutrition counseling with whey protein supplementation, and psychological guidance. Patients in the control group (n = 36) received the usual clinical care. The assessors were blinded to the patient allocation. The primary outcome was perioperative functional capacity measured as the 6-minute walk distance (6MWD), which was assessed at 1 day before and 30 days after surgery. A linear mixed-effects model was built to analyze the perioperative 6MWD. Other outcomes included lung function, disability and psychometric evaluations, length of stay (LOS), short-term recovery quality, postoperative complications, and mortality. RESULTS: The median duration of prehabilitation was 15 days. The average 6MWD was 60.9 m higher perioperatively in the prehabilitation group compared to the control group (95% confidence interval [CI], 32.4-89.5; P < .001). There were no differences in lung function, disability and psychological assessment, LOS, short-term recovery quality, postoperative complications, and mortality, except for forced vital capacity (FVC; 0.35 L higher in the prehabilitation group, 95% CI, 0.05-0.66; P = .021). CONCLUSIONS: A 2-week, home-based, multimodal prehabilitation program could produce clinically relevant improvements in perioperative functional capacity in patients undergoing VATS lobectomy for lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Aptidão Cardiorrespiratória , Serviços Hospitalares de Assistência Domiciliar , Neoplasias Pulmonares/cirurgia , Estado Nutricional , Pneumonectomia/reabilitação , Cuidados Pré-Operatórios , Cirurgia Torácica Vídeoassistida/reabilitação , Idoso , Pequim , Exercícios Respiratórios , Aconselhamento , Suplementos Nutricionais , Tolerância ao Exercício , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonectomia/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Recuperação de Função Fisiológica , Terapia de Relaxamento , Treinamento Resistido , Método Simples-Cego , Cirurgia Torácica Vídeoassistida/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Proteínas do Soro do Leite/administração & dosagem
19.
Clin Exp Dermatol ; 45(8): 974-979, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32852805

RESUMO

This review is part of a series of annual updates that summarize the evidence base for atopic eczema (AE). The aim is to provide a succinct guide for clinicians on the key findings from 14 systematic reviews on the prevention and topical treatment of AE published or indexed in 2018. Various supplements, including long-chain polyunsaturated fatty acids, vitamin D and the probiotic Lactobacillus rhamnosus GG, given prenatally and postnatally, have not been shown to prevent AE in infants, although mixed strains of probiotics may decrease the risk of AE if given to the mother during pregnancy and to the infant for the first 6 months of life. In the postnatal period, there is no evidence that hydrolysed formula, compared with cow's milk formula (CMF), reduces the risk of AE in partially breastfed infants. However, weak evidence suggests that a specific partially hydrolysed whey formula decreases the risk of AE compared with CMF. No specific skin practices can be recommended to reduce the eczema risk in healthy term babies. There is weak evidence of a low risk of reversible hypothalamic-pituitary-adrenal axis suppression following 2-4 weeks of treatment with low-potency topical steroids, and conflicting evidence as to whether bleach bathing affects skin flora or AE severity. A single study demonstrated that the topical Janus kinase inhibitor tofacitinib at 2% significantly reduces the Eczema Area and Severity Index compared with vehicle. Topical naltrexone cream 1% improves pruritus (measured using a visual analogue scale) by 30% more than placebo. There is weak evidence that topical alternative therapies, including antioxidants, micronutrients and some herbal medicines, may improve AE.


Assuntos
Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/prevenção & controle , Eczema/tratamento farmacológico , Eczema/prevenção & controle , Administração Tópica , Animais , Aleitamento Materno/estatística & dados numéricos , Terapias Complementares/efeitos adversos , Terapias Complementares/estatística & dados numéricos , Dermatite Atópica/diagnóstico , Eczema/patologia , Ácidos Graxos/administração & dosagem , Ácidos Graxos/uso terapêutico , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Fórmulas Infantis/efeitos adversos , Recém-Nascido , Inibidores de Janus Quinases/administração & dosagem , Inibidores de Janus Quinases/uso terapêutico , Lacticaseibacillus rhamnosus/imunologia , Leite/efeitos adversos , Naltrexona/administração & dosagem , Naltrexona/uso terapêutico , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/uso terapêutico , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Gravidez , Probióticos/uso terapêutico , Preparações Clareadoras de Pele/efeitos adversos , Esteroides/administração & dosagem , Esteroides/farmacologia , Vitamina D/uso terapêutico , Proteínas do Soro do Leite/administração & dosagem , Proteínas do Soro do Leite/efeitos adversos , Proteínas do Soro do Leite/química
20.
Eur J Appl Physiol ; 120(5): 969-983, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32130485

RESUMO

PURPOSE: Space flight and bed rest (BR) lead to a rapid decline in exercise capacity. Whey protein plus potassium bicarbonate diet-supplementation (NUTR) could attenuate this effect by improving oxidative metabolism. We evaluated the impact of 21-day BR and NUTR on fatigue resistance of plantar flexor muscles (PF) during repeated shortening contractions, and whether any change was related to altered energy metabolism and muscle oxygenation. METHODS: Ten healthy men received a standardized isocaloric diet with (n = 5) or without (n = 5) NUTR. Eight bouts of 24 concentric plantar flexions (30 s each bout) with 20 s rest between bouts were employed. PF muscle size was assessed by means of peripheral quantitative computed tomography. PF muscle volume was assessed with magnetic resonance imaging. PF muscle force, contraction velocity, power and surface electromyogram signals were recorded during each contraction, as well as energy metabolism (31P nuclear magnetic resonance spectroscopy) and oxygenation (near-infrared spectroscopy). Cardiopulmonary parameters were measured during an incremental cycle exercise test. RESULTS: BR caused 10-15% loss of PF volume that was partly recovered 3 days after re-ambulation, as a consequence of fluid redistribution. Unexpectedly, PF fatigue resistance was not affected by BR or NUTR. BR induced a shift in muscle metabolism toward glycolysis and some signs of impaired muscle oxygen extraction. NUTR did not attenuate the BR-induced-shift in energy metabolism. CONCLUSIONS: Twenty-one days' BR did not impair PF fatigue resistance, but the shift to glycolytic metabolism and indications of impaired oxygen extraction may be early signs of developing reduced muscle fatigue resistance.


Assuntos
Repouso em Cama/métodos , Suplementos Nutricionais , Contração Muscular , Fadiga Muscular , Debilidade Muscular/dietoterapia , Músculo Esquelético/fisiologia , Proteínas do Soro do Leite/administração & dosagem , Adulto , Metabolismo Energético , Feminino , Pé/fisiologia , Humanos , Masculino , Debilidade Muscular/prevenção & controle
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