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Impact of Adding Protein Supplementation to Exercise Training on Lean Body Mass and Muscle Strength in Burn Patients.
Badawy, MM, Allam, NM
Journal of burn care & research : official publication of the American Burn Association. 2021;(5):968-974
Abstract
Protein catabolism is a common complication after burn injury, leading to a loss of muscle mass and a decrease in muscle strength. The present study was aimed to evaluate the efficacy of combining exercise training with protein supplementation on lean body mass and muscle strength in patients with severe burn. Sixty participants with severe burn >30% of TBSA were randomly distributed into four equal groups of 15 participants per group. Group A (Exercise and Protein) received oral protein supplementation (Inkospor X-TREME; 1.5-2.0 g/kg/d), exercise program, and traditional burn care; group B (Protein) received oral protein supplementation and traditional burn care; group C (Exercise) received exercise program and traditional burn care; and group D (Control) received traditional burn care. Lean body mass was measured using dual-energy x-ray absorptiometry, whereas muscle strength was measured using Biodex 3 Dynamometer System before treatment and 12 weeks after treatment. A significant increase in lean body mass was found in group A compared with that of group B, group C, and group D post-treatment (P < .001). Also, a significant increase was recorded in peak torque of group A compared with that of group B, group C, and group D post-treatment (P < .001). Exercise training can significantly increase lean body mass and peak torque. Protein supplementation can significantly increase lean body mass but cannot significantly increase muscle strength, whereas protein + exercise group has a great impact on lean body mass and muscle power than exercise group and protein group in burn patients.
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Effects of slow- v. fast-digested protein supplementation combined with mixed power training on muscle function and functional capacities in older men.
Dulac, MC, Pion, CH, Lemieux, FC, Pinheiro Carvalho, L, El Hajj Boutros, G, Bélanger, M, Gaudreau, P, Chevalier, S, Morais, JA, Noirez, P, et al
The British journal of nutrition. 2021;(9):1017-1033
Abstract
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.
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Incorporating Milk Protein Isolate into an Energy-Restricted Western-Style Eating Pattern Augments Improvements in Blood Pressure and Triglycerides, but Not Body Composition Changes in Adults Classified as Overweight or Obese: A Randomized Controlled Trial.
Hudson, JL, Zhou, J, Kim, JE, Campbell, WW
Nutrients. 2020;(3)
Abstract
Unhealthy Western-style eating patterns (WSEP) predominate, adversely affecting health. Resistance to improving dietary patterns prompts interest to incorporate a potentially health-promoting ingredient into typical WSEP foods and beverages. We assessed the effect of incorporating isocalorically matched carbohydrates versus milk protein isolate (MPI) into a WSEP on weight loss-induced changes in cardiometabolic health and body composition. In a randomized, double-blind, parallel-design study, 44 participants (age 52 ± 1 years, body mass index (BMI) 31.4 ± 0.5 kg/m2, mean ± standard error) consumed a weight maintenance WSEP (0.8 g total protein/kg/day) for 3 weeks (baseline). After, participants consumed an energy-restricted (750 kcal/day below estimated requirement) WSEP for 16 weeks, randomly assigned to contain either an additional 0.7 g carbohydrate/kg/d (CON: n = 23, 0.8 g total protein/kg/day) or 0.7 g protein/kg/d from MPI (MPI: n = 21, 1.5 g total protein/kg/day) incorporated into foods and beverages. Compared to CON, the MPI favored reductions in average 24 h and sleeping systolic and diastolic blood pressures (BP), waking hours systolic BP, and fasting plasma triglyceride concentrations. Reductions in fasting plasma insulin, glucose, total cholesterol, and low-density lipoprotein cholesterol concentrations were not different between groups. Among all participants, whole body mass, lean mass, fat mass, and thigh muscle area, each decreased over time. For adults finding it difficult to deviate from a WSEP, replacing a portion of their carbohydrate with foods and beverages containing MPI may be an effective dietary strategy to reduce BP after weight loss.
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Allergic sensitisation in infants younger than one year of age.
Skjerven, HO, Hunderi, JOG, Carlsen, KH, Rolfsjord, LB, Nordhagen, L, Berents, TL, Bains, KES, Buchmann, M, Carlsen, KCL
Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology. 2020;(2):203-206
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The Degree of Aminoacidemia after Dairy Protein Ingestion Does Not Modulate the Postexercise Anabolic Response in Young Men: A Randomized Controlled Trial.
Chan, AH, D'Souza, RF, Beals, JW, Zeng, N, Prodhan, U, Fanning, AC, Poppitt, SD, Li, Z, Burd, NA, Cameron-Smith, D, et al
The Journal of nutrition. 2019;(9):1511-1522
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Abstract
BACKGROUND Resistance exercise and dietary protein stimulate muscle protein synthesis (MPS). The rate at which proteins are digested and absorbed into circulation alters peak plasma amino acid concentrations and may modulate postexercise MPS. A novel mineral modified milk protein concentrate (mMPC), with identical amino acid composition to standard milk protein concentrate (MPC), was formulated to induce rapid aminoacidemia. OBJECTIVES The aim of this study was to determine whether rapid aminoacidemia and greater peak essential amino acid (EAA) concentrations induced by mMPC would stimulate greater postresistance exercise MPS, anabolic signaling, and ribosome biogenesis compared to standard dairy proteins, which induce a small but sustained plasma essential aminoacidemia. METHODS Thirty healthy young men (22.5 ± 3.0 y; BMI 23.8 ± 2.7 kg/m2) received primed constant infusions of l-[ring-13C6]-phenylalanine and completed 3 sets of leg presses and leg extensions at 80% of 1 repetition. Afterwards, participants were randomly assigned in a double-blind fashion to consume 25 g mMPC, MPC, or calcium caseinate (CAS). Vastus lateralis biopsies were collected at rest, and 2 and 4 h post exercise. RESULTS Plasma EAA concentrations, including leucine, were 19.2-26.6% greater in the mMPC group 45-90 min post ingestion than in MPC and CAS groups (P < 0.001). Myofibrillar fractional synthetic rate from baseline to 4 h was increased by 82.6 ± 64.8%, 137.8 ± 72.1%, and 140.6 ± 52.4% in the MPC, mMPC, and CAS groups, respectively, with no difference between groups (P = 0.548). Phosphorylation of anabolic signaling targets (P70S6KThr389, P70S6KThr421/Ser424, RPS6Ser235/236, RPS6Ser240/244, P90RSKSer380, 4EBP1) were elevated by <3-fold at both 2 and 4 h post exercise in all groups (P < 0.05). CONCLUSIONS The amplitude of plasma leucine and EAA concentrations does not modulate the anabolic response to resistance exercise after ingestion of 25 g dairy protein in young men. This trial was registered at http://www.anzctr.org.au/ as ACTRN12617000393358.
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Myofibrillar and Mitochondrial Protein Synthesis Rates Do Not Differ in Young Men Following the Ingestion of Carbohydrate with Milk Protein, Whey, or Micellar Casein after Concurrent Resistance- and Endurance-Type Exercise.
Churchward-Venne, TA, Pinckaers, PJM, Smeets, JSJ, Peeters, WM, Zorenc, AH, Schierbeek, H, Rollo, I, Verdijk, LB, van Loon, LJC
The Journal of nutrition. 2019;(2):198-209
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BACKGROUND Whey and micellar casein are high-quality dairy proteins that can stimulate postprandial muscle protein synthesis rates. How whey and casein compare with milk protein in their capacity to stimulate postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates during postexercise recovery is currently unknown. OBJECTIVE The objective of this study was to compare postprandial MyoPS and MitoPS rates after protein-carbohydrate co-ingestion with milk protein, whey, or micellar casein during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men. METHODS In a randomized, double-blind, parallel-group design, 48 healthy, young, recreationally active men (mean ± SEM age: 23 ± 0.3 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and L-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 0 g protein (CHO), 20 g milk protein (MILK), 20 g whey protein (WHEY), or 20 g micellar casein protein (CASEIN) after a sequential bout of resistance- and endurance-type exercise (i.e., concurrent exercise). Blood and muscle biopsies were collected over 360 min during recovery from exercise to assess MyoPS and MitoPS rates and signaling through mammalian target of rapamycin complex 1 (mTORC1). RESULTS Despite temporal differences in postprandial plasma leucine concentrations between treatments (P < 0.001), MyoPS rates over 360 min of recovery did not differ between treatments (CHO: 0.049% ± 0.003%/h; MILK 0.059% ± 0.003%/h; WHEY 0.054% ± 0.002%/h; CASEIN 0.059% ± 0.005%/h; P = 0.11). When MILK, WHEY, and CASEIN were pooled into a single group (PROTEIN), protein co-ingestion resulted in greater MyoPS rates compared with CHO (PROTEIN 0.057% ± 0.002%/h; CHO: 0.049% ± 0.003%/h; P = 0.04). MitoPS rates and signaling through the mTORC1 pathway were similar between treatments. CONCLUSION MyoPS and MitoPS rates do not differ after co-ingestion of either milk protein, whey protein, or micellar casein protein with carbohydrate during recovery from a single bout of concurrent resistance- and endurance-type exercise in recreationally active young men. Co-ingestion of protein with carbohydrate results in greater MyoPS, but not MitoPS rates, when compared with the ingestion of carbohydrate only during recovery from concurrent exercise. This trial was registered at Nederlands Trial Register: NTR5098.
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Myofibrillar and Mitochondrial Protein Synthesis Rates Do Not Differ in Young Men Following the Ingestion of Carbohydrate with Whey, Soy, or Leucine-Enriched Soy Protein after Concurrent Resistance- and Endurance-Type Exercise.
Churchward-Venne, TA, Pinckaers, PJM, Smeets, JSJ, Peeters, WM, Zorenc, AH, Schierbeek, H, Rollo, I, Verdijk, LB, van Loon, LJC
The Journal of nutrition. 2019;(2):210-220
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BACKGROUND Protein ingestion during recovery from resistance-type exercise increases postexercise muscle protein synthesis rates. Whey protein has been reported to have greater anabolic properties than soy protein, an effect which may be attributed to the higher leucine content of whey. OBJECTIVE The objective of this study was to compare postprandial myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates after ingestion of carbohydrate with whey, soy, or soy protein enriched with free leucine (to match the leucine content of whey) during recovery from a single bout of concurrent resistance- and endurance-type exercise in young healthy men. METHODS In a randomized, double-blind, parallel-group design, 36 healthy young recreationally active men (mean ± SEM age: 23 ± 0.4 y) received a primed continuous infusion of l-[ring-13C6]-phenylalanine and l-[ring-3,5-2H2]-tyrosine and ingested 45 g carbohydrate with 20 g protein from whey (WHEY), soy (SOY), or leucine-enriched soy (SOY + LEU) after concurrent resistance- and endurance-type exercise. Blood and muscle biopsies were collected over a 360 min postexercise recovery period to assess MyoPS and MitoPS rates, and associated signaling through the mammalian target of rapamycin complex 1 (mTORC1). RESULTS Postprandial peak plasma leucine concentrations were significantly higher in WHEY (mean ± SEM: 322 ± 10 μmol/L) and SOY + LEU (328 ± 14 μmol/L) compared with SOY (216 ± 6 μmol/L) (P < 0.05). Despite the apparent differences in plasma leucinemia, MyoPS (WHEY: 0.054 ± 0.002; SOY: 0.053 ± 0.004; SOY + LEU: 0.056 ± 0.004%·h-1; P = 0.83), and MitoPS (WHEY: 0.061 ± 0.004; SOY: 0.061 ± 0.006; SOY + LEU: 0.063 ± 0.004%·h-1; P = 0.96) rates over the entire 360 min recovery period did not differ between treatments. Similarly, signaling through mTORC1Ser2448, p70S6kThr389, 4E-BP1Thr37/46, and rpS6Ser235/236 was similar between treatments. CONCLUSION Postexercise MyoPS and MitoPS rates do not differ after co-ingestion of carbohydrate with 20 g protein from whey, soy, or leucine-enriched soy protein during 360 min of recovery from concurrent resistance- and endurance-type exercise in young, recreationally active men. This trial was registered at Nederlands Trial Register as NTR5098.
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Even effect of milk protein and carbohydrate intake but no further effect of heavy resistance exercise on myofibrillar protein synthesis in older men.
Reitelseder, S, Dideriksen, K, Agergaard, J, Malmgaard-Clausen, NM, Bechshoeft, RL, Petersen, RK, Serena, A, Mikkelsen, UR, Holm, L
European journal of nutrition. 2019;(2):583-595
Abstract
PURPOSE The responsiveness of older individuals' skeletal muscle to anabolic strategies may be impaired. However, direct comparisons within the same experimental setting are sparse. The aim of this study was to assess the resting and post-resistance exercise muscle protein synthesis rates in response to two types of milk protein and carbohydrate using a unilateral exercise leg model. METHODS Twenty-seven older (69 ± 1 year, mean ± SE) men were randomly assigned one of three groups: Whey hydrolysate (WH), caseinate (CAS), or carbohydrate (CHO). By applying stable isotope tracer techniques (L-[15N]phenylalanine), the fasted-rested (basal) myofibrillar fractional synthesis rate (FSR) was measured. Hereafter, FSR was measured in the postprandial phase (0.45 g nutrient/kg LBM) in both legs, one rested (fed-rest) and one exercised (10 × 8 reps at 70% 1RM; fed-exercise). In addition, the activity of p70S6K and venous plasma insulin, phenylalanine, and leucine concentrations were measured. RESULTS Insulin, phenylalanine, and leucine concentrations differed markedly after intake of the different study drinks. The basal FSR in WH, CAS, and CHO were 0.027 ± 0.003, 0.030 ± 0.003, and 0.030 ± 0.004%/h, the fed-rested FSR were 0.043 ± 0.004, 0.045 ± 0.003, and 0.035 ± 0.004%/h, and the fed-exercised FSR were 0.041 ± 0.004, 0.043 ± 0.004, and 0.034 ± 0.004%/h, respectively. No significant differences were observed at any state between the groups. Fed-rested- and fed-exercised FSR were higher than basal (P < 0.001). 3 h after exercise and feeding, no significant group differences were detected in the activity of p70S6K. CONCLUSIONS Milk protein and carbohydrate supplementation stimulate myofibrillar protein synthesis in older men, with no further effect of heavy resistance exercise within 0-3 h post exercise.
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Dairy milk proteins attenuate hyperglycemia-induced impairments in vascular endothelial function in adults with prediabetes by limiting increases in glycemia and oxidative stress that reduce nitric oxide bioavailability.
McDonald, JD, Mah, E, Chitchumroonchokchai, C, Dey, P, Labyk, AN, Villamena, FA, Volek, JS, Bruno, RS
The Journal of nutritional biochemistry. 2019;:165-176
Abstract
Postprandial hyperglycemia (PPH) transiently impairs vascular endothelial function (VEF) in an oxidative stress-dependent manner by decreasing nitric oxide (NO•) bioavailability. Dairy milk and its proteins attenuate PPH, but whether this improves VEF is unknown. We hypothesized that dairy milk, mediated by its whey and/or casein proteins, improves VEF by attenuating PPH-induced oxidative stress that otherwise decreases NO• bioavailability. A randomized, cross-over trial was conducted in adults with prediabetes (n=23) who ingested glucose (75 g, GLU) alone or with 473 mL of non-fat dairy milk (MILK) or isonitrogenous (16.5 g) amounts of whey (WHEY) or casein (CASEIN) in 473 mL of water. Prior to and at 30 min intervals for 180 min postprandially, we assessed brachial artery flow-mediated dilation (FMD) and measured biomarkers of glycemic control, oxidative stress, and NO• homeostasis. FMDAUC decreased to the greatest extent during GLU, which was similarly improved in dairy trials. Compared with GLU, AUCs for glucose, malondialdehyde, F2-isoprostanes, methylglyoxal, and endothelin-1 were similarly lower in dairy trials. Plasma arginine and NO• metabolites were greater but methylated arginine metabolites were lower in dairy trials compared with GLU. Postprandial insulin, lipids, and tetrahydrobiopterin redox status did not differ among trials. Thus, dairy milk, mediated by its whey and casein proteins, attenuates PPH-mediated impairments in VEF by limiting oxidative stress. This improves NO• bioavailability to the vascular endothelium by increasing arginine availability and limiting competitive inhibition on NO• biosynthesis by asymmetric dimethylarginine. These findings support observational studies that dairy milk lowers cardiovascular disease risk.
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Predicting development of sustained unresponsiveness to milk oral immunotherapy using epitope-specific antibody binding profiles.
Suárez-Fariñas, M, Suprun, M, Chang, HL, Gimenez, G, Grishina, G, Getts, R, Nadeau, K, Wood, RA, Sampson, HA
The Journal of allergy and clinical immunology. 2019;(3):1038-1046
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BACKGROUND In a recent trial of milk oral immunotherapy (MOIT) with or without omalizumab in 55 patients with milk allergy treated for 28 months, 44 of 55 subjects passed a 10-g desensitization milk protein challenge; 23 of 55 subjects passed the 10-g sustained unresponsiveness (SU) challenge 8 weeks after discontinuing MOIT. OBJECTIVE We sought to determine whether IgE and IgG4 antibody binding to allergenic milk protein epitopes changes with MOIT and whether this could predict the development of SU. METHODS By using a novel high-throughput Luminex-based assay to quantitate IgE and IgG4 antibody binding to 66 sequential epitopes on 5 milk proteins, serum samples from 47 subjects were evaluated before and after MOIT. Machine learning strategies were used to predict whether a subject would have SU after 8 weeks of MOIT discontinuation. RESULTS MOIT profoundly altered IgE and IgG4 binding to epitopes, regardless of treatment outcome. At the initiation of MOIT, subjects achieving SU exhibited significantly less antibody binding to 40 allergenic epitopes than subjects who were desensitized only (false discovery rate ≤ 0.05 and fold change > 1.5). Based on baseline epitope-specific antibody binding, we developed predictive models of SU. Using simulations, we show that, on average, IgE-binding epitopes alone perform significantly better than models using standard serum component proteins (average area under the curve, >97% vs 80%). The optimum model using 6 IgE-binding epitopes achieved a 95% area under the curve and 87% accuracy. CONCLUSION Despite the relatively small sample size, we have shown that by measuring the epitope repertoire, we can build reliable models to predict the probability of SU after MOIT. Baseline epitope profiles appear more predictive of MOIT response than those based on serum component proteins.