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Bülow J, Khakimov B, Reitelseder S, Bechshøft R, Jensen M, van Hall G, Engelsen SB, Holm L. Effect of 1-year daily protein supplementation and physical exercise on muscle protein synthesis rate and muscle metabolome in healthy older Danes: a randomized controlled trial. Eur J Nutr 2023; 62:2673-2685. [PMID: 37266586 PMCID: PMC10421766 DOI: 10.1007/s00394-023-03182-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 05/22/2023] [Indexed: 06/03/2023]
Abstract
BACKGROUND The skeletal muscle mass decreases with age and the responsiveness of aging muscles' protein synthesis rate (MPS) to protein intake seems to deteriorate. OBJECTIVE This study investigated the impact of 12 months of protein supplementation with or without physical exercise training on the basal and postprandial MPS and the skeletal muscle metabolome of healthy older Danes (> 65 years, 29 females/37 males). METHODS Subjects were randomized to follow one of five intervention groups: (1) carbohydrate, (2) collagen protein, (3) whey protein, (4) home-based light resistance training with whey protein, and (5) center-based heavy-load resistance training with whey protein. Before and after the intervention, a tracer infusion trial was conducted to measure basal and postprandial MPS in response to intake of a cocktail consisting of 20 g whey hydrolysate + 10 g glucose. In addition, the skeletal muscle metabolome was measured using gas chromatography-mass spectrometry (GC-MS) at basal state and 4 h after the intake of the cocktail. RESULTS One year of daily protein or carbohydrate supplementation did not alter the basal and protein-stimulated postprandial muscle protein synthesis rate or the muscle metabolome of healthy older Danes. Basal MPS (%/h) at baseline for all subjects were 0.0034 ± 0,011 (mean ± SD). In contrast to previous studies, no difference was observed in basal MPS between males and females (p = 0.75). With the developed untargeted GC-MS methodology, it was possible to detect and tentatively annotate > 70 metabolites from the human skeletal muscle samples. CONCLUSION One year of protein supplementation in comparison to an isocaloric-control supplement seems to affect neither the MPS at basal or postprandial state nor the skeletal muscle metabolome. CLINICAL TRIAL REGISTRY Number: NCT02115698, clinicaltrials.gov/ct2/show/NCT02115698.
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Affiliation(s)
- Jacob Bülow
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen M81, Bispebjerg Hospital, Building 8, Level 1, Nielsine Nielsens Vej 11, 2400, Copenhagen NV, Denmark.
| | - Bekzod Khakimov
- Department of Food Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen M81, Bispebjerg Hospital, Building 8, Level 1, Nielsine Nielsens Vej 11, 2400, Copenhagen NV, Denmark
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rasmus Bechshøft
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen M81, Bispebjerg Hospital, Building 8, Level 1, Nielsine Nielsens Vej 11, 2400, Copenhagen NV, Denmark
| | - Mikkel Jensen
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen M81, Bispebjerg Hospital, Building 8, Level 1, Nielsine Nielsens Vej 11, 2400, Copenhagen NV, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | | | - Lars Holm
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
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West S, Monteyne AJ, Whelehan G, van der Heijden I, Abdelrahman DR, Murton AJ, Finnigan TJA, Stephens FB, Wall BT. Ingestion of mycoprotein, pea protein, and their blend support comparable postexercise myofibrillar protein synthesis rates in resistance-trained individuals. Am J Physiol Endocrinol Metab 2023; 325:E267-E279. [PMID: 37529834 PMCID: PMC10655824 DOI: 10.1152/ajpendo.00166.2023] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/03/2023]
Abstract
Pea protein is an attractive nonanimal-derived protein source to support dietary protein requirements. However, although high in leucine, a low methionine content has been suggested to limit its anabolic potential. Mycoprotein has a complete amino acid profile which, at least in part, may explain its ability to robustly stimulate myofibrillar protein synthesis (MyoPS) rates. We hypothesized that an inferior postexercise MyoPS response would be seen following ingestion of pea protein compared with mycoprotein, which would be (partially) rescued by blending the two sources. Thirty-three healthy, young [age: 21 ± 1 yr, body mass index (BMI): 24 ± 1 kg·m-2] and resistance-trained participants received primed, continuous infusions of l-[ring-2H5]phenylalanine and completed a bout of whole body resistance exercise before ingesting 25 g of protein from mycoprotein (MYC, n = 11), pea protein (PEA, n = 11), or a blend (39% MYC, 61% PEA) of the two (BLEND, n = 11). Blood and muscle samples were taken pre-, 2 h, and 4 h postexercise/protein ingestion to assess postabsorptive and postprandial postexercise myofibrillar protein fractional synthetic rates (FSRs). Protein ingestion increased plasma essential amino acid and leucine concentrations (time effect; P < 0.0001), but more rapidly in BLEND and PEA compared with MYC (time × condition interaction; P < 0.0001). From similar postabsorptive values (MYC, 0.026 ± 0.008%·h-1; PEA, 0.028 ± 0.007%·h-1; BLEND, 0.026 ± 0.006%·h-1), resistance exercise and protein ingestion increased myofibrillar FSRs (time effect; P < 0.0001) over a 4-h postprandial period (MYC, 0.076 ± 0.004%·h-1; PEA, 0.087 ± 0.01%·h-1; BLEND, 0.085 ± 0.01%·h-1), with no differences between groups (all; P > 0.05). These data show that all three nonanimal-derived protein sources have utility in supporting postexercise muscle reconditioning.NEW & NOTEWORTHY This study provides evidence that pea protein (PEA), mycoprotein (MYC), and their blend (BLEND) can support postexercise myofibrillar protein synthesis rates following a bout of whole body resistance exercise. Furthermore, these data suggest that a methionine deficiency in pea may not limit its capacity to stimulate an acute increase in muscle protein synthesis (MPS).
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Affiliation(s)
- Sam West
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Alistair J Monteyne
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Gráinne Whelehan
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Ino van der Heijden
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas, United States
- Sealy Center of Aging, University of Texas Medical Branch, Galveston, Texas, United States
| | - Andrew J Murton
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas, United States
- Sealy Center of Aging, University of Texas Medical Branch, Galveston, Texas, United States
| | | | - Francis B Stephens
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
| | - Benjamin T Wall
- Department of Public Health and Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom
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Iepsen UW, Rinnov AR, Munch GW, Rugbjerg M, Winding KM, Lauridsen C, Berg RMG, Pedersen BK, Gluud LL, van Hall G. Skeletal muscle protein turnover responses to parenteral nutrition in patients with alcoholic liver cirrhosis and sarcopenia. Am J Physiol Gastrointest Liver Physiol 2023; 325:G174-G183. [PMID: 37339940 DOI: 10.1152/ajpgi.00242.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 03/27/2023] [Accepted: 06/13/2023] [Indexed: 06/22/2023]
Abstract
Alcoholic liver cirrhosis (ALC) is accompanied by sarcopenia. The aim of this study was to investigate the acute effects of balanced parenteral nutrition (PN) on skeletal muscle protein turnover in ALC. Eight male patients with ALC and seven age- and sex-matched healthy controls were studied for 3 h of fasting followed by 3 h of intravenous PN (SmofKabiven 1,206 mL: amino acid = 38 g, carbohydrates = 85 g, and fat = 34 g) 4 mL/kg/h. We measured leg blood flow and sampled paired femoral arteriovenous concentrations and quadriceps muscle biopsies while providing a primed continuous infusion of [ring-2d5]-phenylalanine to quantify muscle protein synthesis and breakdown. Patients with ALC exhibited shorter 6-min walking distance (ALC: 487 ± 38 vs. controls: 722 ± 14 m, P < 0.05), lower hand-grip strength (ALC: 34 ± 2 vs. controls: 52 ± 2 kg, P < 0.05), and computed tomography (CT)-verified leg muscle loss (ALC: 5,922 ± 246 vs. controls: 8,110 ± 345 mm2, P < 0.05). Net leg muscle phenylalanine uptake changed from negative (muscle loss) during fasting to positive (muscle gain) in response to PN (ALC: -0.18 ± +0.01 vs. 0.24 ± 0.03 µmol/kg muscle·min-1; P < 0.001 and controls: -0.15 ± 0.01 vs. 0.09 ± 0.01 µmol/kg muscle·min-1; P < 0.001) but with higher net muscle phenylalanine uptake in ALC than controls (P < 0.001). Insulin concentrations were substantially higher in patients with ALC during PN. Our results suggest a higher net muscle phenylalanine uptake during a single infusion of PN in stable patients with ALC with sarcopenia compared with healthy controls.NEW & NOTEWORTHY Muscle protein turnover responses to parenteral nutritional (PN) supplementation have not previously been studied in stable alcoholic liver cirrhosis (ALC). We applied stable isotope tracers of amino acids to directly quantify net muscle protein turnover responses to PN in sarcopenic males with ALC and healthy controls. We found a higher net muscle protein gain in ALC during PN, thereby providing the physiological rationale for future clinical trials of PN as a potential countermeasure to sarcopenia.
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Affiliation(s)
- Ulrik Winning Iepsen
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Anaesthesiology and Intensive Care, Copenhagen University Hospital-Hvidovre Hospital, Copenhagen, Denmark
| | - Anders Rasmussen Rinnov
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Gregers Winding Munch
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Mette Rugbjerg
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Kamilla Munch Winding
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Carsten Lauridsen
- Department of Diagnostic Radiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Technology, Copenhagen University College, Copenhagen, Denmark
| | - Ronan M G Berg
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, United Kingdom
| | - Bente Klarlund Pedersen
- The Centre for Physical Activity Research, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Lise Lotte Gluud
- Gastro Unit, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Clinical Biochemistry, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Biomedical Sciences, Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Cramer A, Højfeldt G, Schjerling P, Agergaard J, van Hall G, Olsen J, Hölmich P, Kjaer M, Barfod KW. Achilles Tendon Tissue Turnover Before and Immediately After an Acute Rupture. Am J Sports Med 2023; 51:2396-2403. [PMID: 37313851 DOI: 10.1177/03635465231177890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
BACKGROUND An Achilles tendon rupture (ATR) is a frequent injury and results in the activation of tendon cells and collagen expression, but it is unknown to what extent turnover of the tendon matrix is altered before or after a rupture. PURPOSE/HYPOTHESIS The purpose of this study was to characterize tendon tissue turnover before and immediately after an acute rupture in patients. It was hypothesized that a rupture would result in pronounced collagen synthesis in the early phase (first 2 weeks) after the injury. STUDY DESIGN Cross-sectional study; Level of evidence, 3. METHODS The study included patients (N = 18) eligible for surgery after an ATR. At the time of inclusion, the patients ingested deuterium oxide (2H2O) orally, and on the day of surgery (within 14 days of the injury), they received a 3-hour flood-primed infusion of an 15N-proline tracer. During surgery, the patients had 1 biopsy specimen taken from the ruptured part of the Achilles tendon and 1 that was 3 to 5 cm proximal to the rupture as a control. The biopsy specimens were analyzed for carbon-14 (14C) levels in the tissue to calculate long-term turnover (years), incorporation of 2H-alanine (from 2H2O) into the tissue to calculate the fractional synthesis rate (FSR) of proteins in the short term (days), and incorporation of 15N-proline into the tissue to calculate the acute FSR (hours). RESULTS Both the rupture and the control samples showed consistently lower levels of 14C compared with the predicted level of 14C in a healthy tendon, which indicated increased tendon turnover in a fraction (48% newly synthesized) of the Achilles tendon already for a prolonged period before the rupture. Over the first days after the rupture, the synthesis rate for collagen was relatively constant, and the average synthesis rate on the day of surgery (2-14 days after the rupture) was 0.025% per hour, irrespective of the length of time after a rupture and the site of sampling (rupture vs control). No differences were found in the FSR between the rupture and control samples in the days after the rupture. CONCLUSION Higher than normal tissue turnover in the Achilles tendon before a rupture indicated that changes in the tendon tissue preceded the injury. In addition, we observed no increase in tendon collagen tissue turnover in the first 2 weeks after an ATR. This favors the view that an increase in the formation of new tendon collagen is not an immediate phenomenon during the regeneration of ruptured tendons in patients. REGISTRATION NCT03931486 (ClinicalTrials.gov identifier).
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Affiliation(s)
- Allan Cramer
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Olsen
- Aarhus AMS Centre, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - Per Hölmich
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristoffer Weisskirchner Barfod
- Sports Orthopedic Research Center-Copenhagen, Department of Orthopedic Surgery, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark
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Comparing Even with Skewed Dietary Protein Distribution Shows No Difference in Muscle Protein Synthesis or Amino Acid Utilization in Healthy Older Individuals: A Randomized Controlled Trial. Nutrients 2022; 14:nu14214442. [PMID: 36364705 PMCID: PMC9654411 DOI: 10.3390/nu14214442] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/19/2022] [Accepted: 10/20/2022] [Indexed: 11/22/2022] Open
Abstract
Sarcopenia is a multifactorial disease that limits autonomy for the growing elderly population. An optimal amount of dietary protein has shown to be important to maintain muscle mass during aging. Yet, the optimal distribution of that dietary protein has not been fully clarified. The aim of the present study was to examine whether an even, compared to a skewed, distribution of daily dietary protein leads to higher muscle protein synthesis and amino acid utilization. Twelve healthy males and twelve healthy females aged between 65 and 80 years were block randomized to either an even (EVEN, n = 12) or skewed (SKEWED, n = 12) dietary protein distribution for three daily main meals. Seven days of habituation were followed by three trial days, which were initiated by oral intake of deuterium oxide (D2O). The dietary protein throughout all trial meals was intrinsically labelled with 2H5-phenylalanine. Blood samples were drawn daily, and muscle biopsies were taken before and at the end of the trial to measure muscle protein synthesis (FSR) and muscle protein incorporation of the dietary-protein-derived tracer. Muscle protein FSR was no different between the two groups (EVEN 2.16 ± 0.13%/day and SKEWED 2.23 ± 0.09%/day, p = 0.647), and the muscle protein incorporation of the intrinsically labeled 2H5-phenylalanine tracer was not different between the two groups (EVEN 0.0049 ± 0.0004 MPE% and SKEWED 0.0054 ± 0.0003 MPE%, p = 0.306). In conclusion, the daily distribution pattern of the dietary protein did not affect muscle protein synthesis or the utilization of dietary protein.
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Using the dual isotope method to assess cecal amino acid absorption of goat whey protein in rats, a pilot study. Amino Acids 2022; 54:811-821. [PMID: 35192060 DOI: 10.1007/s00726-022-03137-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 02/07/2022] [Indexed: 11/01/2022]
Abstract
Measurement of ileal amino acids (AA) bioavailability is recommended to evaluate protein quality. A dual isotope tracer method, based on plasma isotopic enrichment ratios, has been proposed to determine true digestibility in humans. In a pilot study, we aimed to evaluate whether this method could be implemented in rats to determine AA bioavailability based on isotopic enrichment ratios measured in cecal digesta or plasma samples. Goat milk proteins were intrinsically labeled with 15N and 2H. Wistar rats were fed a meal containing the doubly labeled goat whey proteins and a tracer dose of 13C-spirulina. Blood samples were collected 0, 1 h and 3 h after meal ingestion from the tail vein. The rats were euthanized 4 h (n = 6) or 6 h (n = 6) after meal to collect plasma and intestinal contents. True orocecal protein digestibility and AA bioavailability were assessed by means of 15N and 2H enrichment in cecum content and compared with absorption indexes determined at the plasma or cecum level using isotopic ratios. Plasma kinetics of isotopic enrichment could not be completed due to the limited quantity of plasma obtained with sequential blood collection. However, the absorption indexes determined from cecal 15N or 2H/13C ratios gave coherent values with true orocecal AA bioavailability. This dual isotope approach with measurements of isotopic ratios in digestive content could be an interesting strategy to determine true AA bioavailability in ileal digesta of rats.
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Nishimura Y, Jensen M, Bülow J, Thomsen TT, Arimitsu T, van Hall G, Fujita S, Holm L. Co-ingestion of cluster dextrin carbohydrate does not increase exogenous protein-derived amino acid release or myofibrillar protein synthesis following a whole-body resistance exercise in moderately trained younger males: a double-blinded randomized controlled crossover trial. Eur J Nutr 2022; 61:2475-2491. [PMID: 35182194 PMCID: PMC9279228 DOI: 10.1007/s00394-021-02782-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/09/2021] [Indexed: 11/12/2022]
Abstract
Purpose This study investigates if co-ingestion of cluster dextrin (CDX) augments the appearance of intrinsically labeled meat protein hydrolysate-derived amino acid (D5-phenylalanine), Akt/mTORC1 signaling, and myofibrillar protein fractional synthetic rate (FSR). Methods Ten moderately trained healthy males (age: 21.5 ± 2.1 years, body mass: 75.7 ± 7.6 kg, body mass index (BMI): 22.9 ± 2.1 kg/m2) were included for a double-blinded randomized controlled crossover trial. Either 75 g of CDX or glucose (GLC) was given in conjunction with meat protein hydrolysate (0.6 g protein * FFM−1) following a whole-body resistance exercise. A primed-continuous intravenous infusion of L-[15N]-phenylalanine with serial muscle biopsies and venous blood sampling was performed. Results A time × group interaction effect was found for serum D5-phenylalanine enrichment (P < 0.01). Serum EAA and BCAA concentrations showed a main effect for group (P < 0.05). Tmax serum BCAA was greater in CDX as compared to GLC (P < 0.05). However, iAUC of all serum parameters did not differ between CDX and GLC (P > 0.05). Tmax serum EAA showed a trend towards a statistical significance favoring CDX over GLC. The phosphorylation of p70S6KThr389, rpS6Ser240/244, ERK1/2Thr202/Tyr204 was greater in CDX compared to GLC (P < 0.05). However, postprandial myofibrillar FSR did not differ between CDX and GLC (P = 0.17). Conclusion In moderately trained younger males, co-ingestion of CDX with meat protein hydrolysate does not augment the postprandial amino acid availability or myofibrillar FSR as compared to co-ingestion of GLC during the recovery from a whole-body resistance exercise despite an increased intramuscular signaling. Trial registration ClinicalTrials.gov ID: NCT03303729 (registered on October 3, 2017).
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Affiliation(s)
- Yusuke Nishimura
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.,Department of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Mikkel Jensen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jacob Bülow
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Thomas Tagmose Thomsen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Takuma Arimitsu
- Department of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Satoshi Fujita
- Department of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Lars Holm
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. .,Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark. .,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Højfeldt G, Bülow J, Agergaard J, Simonsen LR, Bülow J, Schjerling P, van Hall G, Holm L. Postprandial muscle protein synthesis rate is unaffected by 20-day habituation to a high protein intake: a randomized controlled, crossover trial. Eur J Nutr 2021; 60:4307-4319. [PMID: 34032900 DOI: 10.1007/s00394-021-02590-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 05/12/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE During the last decade more researchers have argued in favor of an increased protein intake for older adults. However, there is a lack of knowledge on the long-term effects of conforming to such a high protein intake with regards to the basal and postprandial muscle protein turnover. The purpose of this study was to compare the postprandial synthesis response in muscle proteins, and the abundance of directly incorporated food-derived amino acids following habituation to high vs. recommended level of protein intake. METHODS In a double blinded crossover intervention 11 older male participants (66.6 ± 1.7 years of age) were habituated for 20 days to a recommended protein (RP) intake (1.1 g protein/kg lean body mass (LBM)/day) and a high protein (HP) intake (> 2.1 g protein/kg LBM/day). Following each habituation period, intrinsically labelled proteins were ingested as part of a mixed meal to determine the incorporation of meal protein-derived amino acids into myofibrillar proteins. Furthermore, the myofibrillar fractional synthesis rate (FSR) and amino acid kinetics across the leg were determined using gold standard stable isotope tracer methodologies. RT qPCR was used to assess the expression of markers related to muscle proteinsynthesis and breakdown. RESULTS No impact of habituation was observed on skeletal muscle amino acid or protein kinetics. However, the shunting of amino acids directly from artery to vein was on average 2.9 [Formula: see text]mol/min higher following habituation to HP compared to RP. CONCLUSIONS In older males, habituation to a higher than the currently recommended protein intake did not demonstrate any adaptions in the muscle protein turnover or markers hereof when subjected to an intake of an identical mixed meal. CLINICAL TRIAL REGISTRY Journal number NCT02587156, Clinicaltrials.org. Date of registration: October 27th, 2015.
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Affiliation(s)
- Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark.
| | - Jacob Bülow
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Lene R Simonsen
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, Frederiksberg, Denmark
| | - Jens Bülow
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, Frederiksberg, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Clinical Metabolomics Core Facility, Department of Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
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9
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Højfeldt G, Bülow J, Agergaard J, Asmar A, Schjerling P, Simonsen L, Bülow J, van Hall G, Holm L. Impact of habituated dietary protein intake on fasting and postprandial whole-body protein turnover and splanchnic amino acid metabolism in elderly men: a randomized, controlled, crossover trial. Am J Clin Nutr 2020; 112:1468-1484. [PMID: 32710741 DOI: 10.1093/ajcn/nqaa201] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 06/29/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Efficacy of protein absorption and subsequent amino acid utilization may be reduced in the elderly. Higher protein intakes have been suggested to counteract this. OBJECTIVES We aimed to elucidate how habituated amounts of protein intake affect the fasted state of, and the stimulatory effect of a protein-rich meal on, protein absorption, whole-body protein turnover, and splanchnic amino acid metabolism. METHODS Twelve men (65-70 y) were included in a double-blinded crossover intervention study, consisting of a 20-d habituation period to a protein intake at the RDA or a high amount [1.1 g · kg lean body mass (LBM)-1 · d-1 or >2.1 g · kg LBM-1 · d-1, respectively], each followed by an experimental trial with a primed, constant infusion of D8-phenylalanine and D2-tyrosine. Arterial and hepatic venous blood samples were obtained after an overnight fast and repeatedly 4 h after a standardized meal including intrinsically labeled whey protein concentrate and calcium-caseinate proteins. Blood was analyzed for amino acid concentrations and phenylalanine and tyrosine tracer enrichments from which whole-body and splanchnic amino acid and protein kinetics were calculated. RESULTS High (compared with the recommended amount of) protein intake resulted in a higher fasting whole-body protein turnover with a resultant mean ± SEM 0.03 ± 0.01 μmol · kg LBM-1 · min-1 lower net balance (P < 0.05), which was not rescued by the intake of a protein-dense meal. The mean ± SEM plasma protein fractional synthesis rate was 0.13 ± 0.06%/h lower (P < 0.05) after habituation to high protein. Furthermore, higher fasting and postprandial amino acid removal were observed after habituation to high protein, yielding higher urea excretion and increased phenylalanine oxidation rates (P < 0.01). CONCLUSIONS Three weeks of habituation to high protein intake (>2.1 g protein · kg LBM-1 · d-1) led to a significantly higher net protein loss in the fasted state. This was not compensated for in the 4-h postprandial period after intake of a meal high in protein.This trial was registered at clinicaltrials.gov as NCT02587156.
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Affiliation(s)
- Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jacob Bülow
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen, Denmark
| | - Ali Asmar
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark.,Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lene Simonsen
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Jens Bülow
- Department of Clinical Physiology and Nuclear Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Clinical Metabolomics Core Facility, Clinical Biochemistry, Rigshospitalet, Copenhagen, Rigshospitalet, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
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10
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Monteyne AJ, Coelho MOC, Porter C, Abdelrahman DR, Jameson TSO, Jackman SR, Blackwell JR, Finnigan TJA, Stephens FB, Dirks ML, Wall BT. Mycoprotein ingestion stimulates protein synthesis rates to a greater extent than milk protein in rested and exercised skeletal muscle of healthy young men: a randomized controlled trial. Am J Clin Nutr 2020; 112:318-333. [PMID: 32438401 DOI: 10.1093/ajcn/nqaa092] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/09/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Mycoprotein is a fungal-derived sustainable protein-rich food source, and its ingestion results in systemic amino acid and leucine concentrations similar to that following milk protein ingestion. OBJECTIVE We assessed the mixed skeletal muscle protein synthetic response to the ingestion of a single bolus of mycoprotein compared with a leucine-matched bolus of milk protein, in rested and exercised muscle of resistance-trained young men. METHODS Twenty resistance-trained healthy young males (age: 22 ± 1 y, body mass: 82 ± 2 kg, BMI: 25 ± 1 kg·m-2) took part in a randomized, double-blind, parallel-group study. Participants received primed, continuous infusions of L-[ring-2H5]phenylalanine and ingested either 31 g (26.2 g protein: 2.5 g leucine) milk protein (MILK) or 70 g (31.5 g protein: 2.5 g leucine) mycoprotein (MYCO) following a bout of unilateral resistance-type exercise (contralateral leg acting as resting control). Blood and m. vastus lateralis muscle samples were collected before exercise and protein ingestion, and following a 4-h postprandial period to assess mixed muscle fractional protein synthetic rates (FSRs) and myocellular signaling in response to the protein beverages in resting and exercised muscle. RESULTS Mixed muscle FSRs increased following MILK ingestion (from 0.036 ± 0.008 to 0.052 ± 0.006%·h-1 in rested, and 0.035 ± 0.008 to 0.056 ± 0.005%·h-1 in exercised muscle; P <0.01) but to a greater extent following MYCO ingestion (from 0.025 ± 0.006 to 0.057 ± 0.004%·h-1 in rested, and 0.024 ± 0.007 to 0.072 ± 0.005%·h-1 in exercised muscle; P <0.0001) (treatment × time interaction effect; P <0.05). Postprandial FSRs trended to be greater in MYCO compared with MILK (0.065 ± 0.004 compared with 0.054 ± 0.004%·h-1, respectively; P = 0.093) and the postprandial rise in FSRs was greater in MYCO compared with MILK (Delta 0.040 ± 0.006 compared with Delta 0.018 ± 0.005%·h-1, respectively; P <0.01). CONCLUSIONS The ingestion of a single bolus of mycoprotein stimulates resting and postexercise muscle protein synthesis rates, and to a greater extent than a leucine-matched bolus of milk protein, in resistance-trained young men. This trial was registered at clinicaltrials.gov as 660065600.
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Affiliation(s)
- Alistair J Monteyne
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Mariana O C Coelho
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Craig Porter
- Department of Surgery, University of Texas Medical Branch & Shriners Hospital for Children, Galveston, TX, USA
| | - Doaa R Abdelrahman
- Department of Surgery, University of Texas Medical Branch & Shriners Hospital for Children, Galveston, TX, USA
| | - Thomas S O Jameson
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Sarah R Jackman
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Jamie R Blackwell
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | | | - Francis B Stephens
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Marlou L Dirks
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
| | - Benjamin T Wall
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, Heavitree Road, University of Exeter, Exeter, UK
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11
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Wall BT, Cruz AM, Otten B, Dunlop MV, Fulford J, Porter C, Abdelrahman DR, Stephens FB, Dirks ML. The Impact of Disuse and High-Fat Overfeeding on Forearm Muscle Amino Acid Metabolism in Humans. J Clin Endocrinol Metab 2020; 105:5821526. [PMID: 32303743 DOI: 10.1210/clinem/dgaa184] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 04/16/2020] [Indexed: 01/08/2023]
Abstract
CONTEXT Anabolic resistance is mechanistically implicated in muscle disuse atrophy. OBJECTIVE The objective of this study is to assess whether anabolic resistance is associated with reduced postprandial amino acid uptake or exacerbated by excess lipid availability. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS Twenty men underwent 7 days of forearm immobilization while consuming a eucaloric (CON; n = 11) or high-fat overfeeding (HFD; n = 9; 50% excess energy as fat) diet (parallel design) within our Nutritional Physiology Research Unit. MAIN OUTCOME MEASURES Preimmobilization and postimmobilization we measured forearm muscle cross-sectional area (aCSA), and postabsorptive and postprandial (3-hour postingestion of a liquid, protein-rich, mixed meal) forearm amino acid metabolism using the arterialized venous-deep venous balance method and infusions of L-[ring-2H5]phenylalanine and L-[1-13C]leucine. RESULTS Immobilization did not affect forearm muscle aCSA in either group, but tended to reduce postabsorptive phenylalanine (P = .07) and leucine (P = .05) net balances equivalently in CON and HFD. Mixed-meal ingestion switched phenylalanine and leucine net balances from negative to positive (P < .05), an effect blunted by immobilization (P < .05) and to a greater extent in HFD than CON (P < .05). Preimmobilization, meal ingestion increased leucine rates of disappearance (Rd; P < .05), with values peaking at 191% (from 87 ± 38 to 254 ± 60 µmol·min-1·100 mL forearm volume-1) and 183% (from 141 ± 24 to 339 ± 51 µmol·min-1·100 mL-1) above postabsorptive rates in CON and HFD, respectively, with meal-induced increases not evident postimmobilization in either group (P > .05). CONCLUSIONS Disuse impairs the ability of a protein-rich meal to promote positive muscle amino acid balance, which is aggravated by dietary lipid oversupply. Moreover, disuse reduced postprandial forearm amino acid uptake; however, this is not worsened under high-fat conditions.
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Affiliation(s)
- Benjamin T Wall
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Ana M Cruz
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
- Exeter Medical School, University of Exeter, UK
| | - Britt Otten
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Mandy V Dunlop
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
| | | | - Craig Porter
- Department of Surgery, University of Texas Medical Branch & Metabolism Unit, Shriners Hospital for Children, Galveston, USA
| | - Doaa Reda Abdelrahman
- Department of Surgery, University of Texas Medical Branch & Metabolism Unit, Shriners Hospital for Children, Galveston, USA
| | - Francis B Stephens
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
| | - Marlou L Dirks
- Department of Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, UK
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12
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van Vliet S, Beals JW, Holwerda AM, Emmons RS, Goessens JP, Paluska SA, De Lisio M, van Loon LJC, Burd NA. Time-dependent regulation of postprandial muscle protein synthesis rates after milk protein ingestion in young men. J Appl Physiol (1985) 2019; 127:1792-1801. [PMID: 31725358 DOI: 10.1152/japplphysiol.00608.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The anabolic action of "fast" whey protein on the regulation of postprandial muscle protein synthesis has been established to be short-lived in healthy young adults. We assessed the time course of anabolic signaling activation and stimulation of myofibrillar protein synthesis rates (MPS) after ingestion of a food source that represents a more typical meal-induced pattern of aminoacidemia. Seven young men (age: 22 ± 1 y) underwent repeated blood and biopsy sampling during primed, continuous l-[ring-2H5]phenylalanine and l-[1-13C]leucine tracer infusions and ingested 38 g of l-[1-13C]phenylalanine- and l-[1-13C]leucine-labeled milk protein concentrate. A total of ∼27 ± 4 (∼10 g) and ∼31 ± 1% (∼12 g) of dietary protein-derived amino acids were released in circulation between 0 and 120 min and 120-300 min, respectively, of the postprandial period. l-[ring-2H5]phenylalanine-based MPS increased above basal (0.025 ± 0.008%/h) by ∼75% (0.043 ± 0.009%/h; P = 0.05) between 0 and 120 min and by ∼86% (0.046 ± 0.004%/h; P = 0.02) between 120 and 300 min, respectively. l-[1-13C]leucine-based MPS increased above basal (0.027 ± 0.002%/h) by ∼72% (0.051 ± 0.016%/h; P = 0.10) between 0 and 120 min and by ∼62% (0.047 ± 0.004%/h; P = 0.001) between 120 and 300 min, respectively. Myofibrillar protein-bound l-[1-13C]phenylalanine increased over time (P < 0.001) and equaled 0.004 ± 0.001, 0.008 ± 0.002, 0.017 ± 0.004, and 0.020 ± 0.003 mole percent excess at 60, 120, 180, and 300 min, respectively, of the postprandial period. Milk protein ingestion increased mTORC1 phosphorylation at 120, 180, and 300 min of the postprandial period (all P < 0.05). Our results show that ingestion of 38 g of milk protein results in sustained increases in MPS throughout a 5-h postprandial period in healthy young men.NEW & NOTEWORTHY The stimulation of muscle protein synthesis after whey protein ingestion is short-lived due to its transient systemic appearance of amino acids. Our study characterized the muscle anabolic response to a protein source that results in a more gradual release of amino acids into circulation. Our work demonstrates that a sustained increase in postprandial plasma amino acid availability after milk protein ingestion results in a prolonged stimulation of muscle protein synthesis rates in healthy young men.
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Affiliation(s)
- Stephan van Vliet
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Joseph W Beals
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Andrew M Holwerda
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Russell S Emmons
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Joy P Goessens
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Scott A Paluska
- Department of Family Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Michael De Lisio
- School of Human Kinetics and Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Luc J C van Loon
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Nicholas A Burd
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois.,Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
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13
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Human Muscle Protein Synthesis Rates after Intake of Hydrolyzed Porcine-Derived and Cows' Milk Whey Proteins-A Randomized Controlled Trial. Nutrients 2019; 11:nu11050989. [PMID: 31052297 PMCID: PMC6567276 DOI: 10.3390/nu11050989] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 04/23/2019] [Accepted: 04/28/2019] [Indexed: 11/26/2022] Open
Abstract
Background: Whey protein has been shown to be one of the best proteins to stimulate muscle protein synthesis rate (MPS), but other high quality proteins, e.g., animal/porcine-derived, could have similar effects. Objective: To investigate the effects of hydrolyzed porcine proteins from blood (HPB) and muscle (HPM), in comparison to hydrolyzed whey protein (HW), on MPS after intake of 15 g alone or 30 g protein as part of a mixed meal. We hypothesized that the postprandial MPS would be similar for porcine proteins and whey protein. Design: Eighteen men (mean ± SD age: 24 ± 1 year; BMI: 21.7 ± 0.4 kg/m2) participated in the randomized, double-blind, three-way cross-over study. Subjects consumed the three test products (HPB, HPM and HW) in a random order in two servings at each test day. Serving 1 consisted of a drink with 15 g protein and serving 2 of a drink with 30 g protein together with a mixed meal. A flood-primed continuous infusion of (ring-13C6) phenylalanine was performed and muscle biopsies, blood and urine samples were collected for determination of MPS, muscle free leucine, plasma amino acid concentrations and urea excretion. Results: There were no statistical differences between the MPS measured after consuming 15 g protein alone or 30 g with a mixed meal (p = 0.53) of HPB (0.048 ± 0.007 vs. 0.049 ± 0.008%/h, resp.), HPM (0.063 ± 0.011 vs. 0.062 ± 0.011 %/h, resp.) and HW (0.058 ± 0.007 vs. 0.071 ± 0.013%/h, resp.). However, the impact of protein type on MPS reached statistical tendency (HPB vs. HPM (p = 0.093) and HPB vs. HW (p = 0.067)) with no difference between HPM and HW (p = 0.88). Plasma leucine, branched-chain, essential and total amino acids were generally higher for HPB and HW than HPM (p < 0.01), which reflected their content in the proteins. Muscle-free leucine was higher for HPB than HW and HPM (p < 0.05). Conclusion: Hydrolyzed porcine proteins from blood and muscle resulted in an MPS similar to that of HW, although with a trend for porcine blood proteins to be inferior to muscle proteins and whey. Consequently, these porcine-derived muscle proteins can be used similarly to whey protein to support maintenance of skeletal muscle as part of supplements and ingredients in foods.
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14
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Hulston CJ, Woods RM, Dewhurst‐Trigg R, Parry SA, Gagnon S, Baker L, James LJ, Markey O, Martin NRW, Ferguson RA, van Hall G. Resistance exercise stimulates mixed muscle protein synthesis in lean and obese young adults. Physiol Rep 2018; 6:e13799. [PMID: 30009507 PMCID: PMC6046643 DOI: 10.14814/phy2.13799] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 06/26/2018] [Accepted: 06/27/2018] [Indexed: 12/16/2022] Open
Abstract
Obese individuals exhibit a diminished muscle protein synthesis response to nutrient stimulation when compared with their lean counterparts. However, the effect of obesity on exercise-stimulated muscle protein synthesis remains unknown. Nine lean (23.5 ± 0.6 kg/m2 ) and 8 obese (33.6 ± 1.2 kg/m2 ) physically active young adults participated in a study that determined muscle protein synthesis and intracellular signaling at rest and following an acute bout of resistance exercise. Mixed muscle protein synthesis was determined by combining stable isotope tracer ([13 C6 ]phenylalanine) infusion with serial biopsies of the vastus lateralis. A unilateral leg resistance exercise model was adopted so that resting and postexercise measurements of muscle protein synthesis could be obtained simultaneously. Obesity was associated with higher basal levels of serum insulin (P < 0.05), plasma triacylglycerol (P < 0.01), plasma cholesterol (P < 0.01), and plasma CRP (P < 0.01), as well as increased insulin resistance determined by HOMA-IR (P < 0.05). However, resting and postexercise rates of muscle protein synthesis were not significantly different between lean and obese participants (P = 0.644). Furthermore, resistance exercise stimulated muscle protein synthesis (~50% increase) in both groups (P < 0.001), with no difference between lean and obese (P = 0.809). Temporal increases in the phosphorylation of intracellular signaling proteins (AKT/4EBP1/p70S6K) were observed within the exercised leg (P < 0.05), with no differences between lean and obese. These findings suggest a normal anabolic response to muscle loading in obese young adults.
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Affiliation(s)
- Carl J. Hulston
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Rachel M. Woods
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Rebecca Dewhurst‐Trigg
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Sion A. Parry
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
- Present address:
Sion A. Parry Oxford Centre for Diabetes, Endocrinology and MetabolismUniversity of OxfordChurchill HospitalOxfordUnited Kingdom
| | - Stephanie Gagnon
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Luke Baker
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Lewis J. James
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Oonagh Markey
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Neil R. W. Martin
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Richard A. Ferguson
- School of Sport, Exercise & Health SciencesLoughborough UniversityLoughboroughLeicestershireUnited Kingdom
| | - Gerrit van Hall
- Clinical Metabolomics Core FacilityDepartment of Clinical BiochemistryRigshospitaletDepartment of Biomedical SciencesUniversity of CopenhagenCopenhagenDenmark
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15
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Wilkinson DJ. Historical and contemporary stable isotope tracer approaches to studying mammalian protein metabolism. MASS SPECTROMETRY REVIEWS 2018; 37:57-80. [PMID: 27182900 PMCID: PMC5763415 DOI: 10.1002/mas.21507] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/22/2016] [Indexed: 06/05/2023]
Abstract
Over a century ago, Frederick Soddy provided the first evidence for the existence of isotopes; elements that occupy the same position in the periodic table are essentially chemically identical but differ in mass due to a different number of neutrons within the atomic nucleus. Allied to the discovery of isotopes was the development of some of the first forms of mass spectrometers, driven forward by the Nobel laureates JJ Thomson and FW Aston, enabling the accurate separation, identification, and quantification of the relative abundance of these isotopes. As a result, within a few years, the number of known isotopes both stable and radioactive had greatly increased and there are now over 300 stable or radioisotopes presently known. Unknown at the time, however, was the potential utility of these isotopes within biological disciplines, it was soon discovered that these stable isotopes, particularly those of carbon (13 C), nitrogen (15 N), oxygen (18 O), and hydrogen (2 H) could be chemically introduced into organic compounds, such as fatty acids, amino acids, and sugars, and used to "trace" the metabolic fate of these compounds within biological systems. From this important breakthrough, the age of the isotope tracer was born. Over the following 80 yrs, stable isotopes would become a vital tool in not only the biological sciences, but also areas as diverse as forensics, geology, and art. This progress has been almost exclusively driven through the development of new and innovative mass spectrometry equipment from IRMS to GC-MS to LC-MS, which has allowed for the accurate quantitation of isotopic abundance within samples of complex matrices. This historical review details the development of stable isotope tracers as metabolic tools, with particular reference to their use in monitoring protein metabolism, highlighting the unique array of tools that are now available for the investigation of protein metabolism in vivo at a whole body down to a single protein level. Importantly, it will detail how this development has been closely aligned to the technological development within the area of mass spectrometry. Without the dedicated development provided by these mass spectrometrists over the past century, the use of stable isotope tracers within the field of protein metabolism would not be as widely applied as it is today, this relationship will no doubt continue to flourish in the future and stable isotope tracers will maintain their importance as a tool within the biological sciences for many years to come. © 2016 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc. Mass Spec Rev.
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Affiliation(s)
- Daniel James Wilkinson
- MRC‐ARUK Centre for Musculoskeletal Ageing Research, Clinical, Metabolic and Molecular PhysiologyUniversity of Nottingham, Royal Derby Hospital CentreDerbyUnited Kingdom
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16
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Agergaard J, Bülow J, Jensen JK, Reitelseder S, Drummond MJ, Schjerling P, Scheike T, Serena A, Holm L. Light-load resistance exercise increases muscle protein synthesis and hypertrophy signaling in elderly men. Am J Physiol Endocrinol Metab 2017; 312:E326-E338. [PMID: 27780819 DOI: 10.1152/ajpendo.00164.2016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 09/06/2016] [Accepted: 10/05/2016] [Indexed: 01/18/2023]
Abstract
The present study investigated whether well-tolerated light-load resistance exercise (LL-RE) affects skeletal muscle fractional synthetic rate (FSR) and anabolic intracellular signaling as a way to counteract age-related loss of muscle mass. Untrained healthy elderly (>65-yr-old) men were subjected to 13 h of supine rest. After 2.5 h of rest, unilateral LL-RE, consisting of leg extensions (10 sets, 36 repetitions) at 16% of 1 repetition maximum (RM), was conducted. Subsequently, the subjects were randomized to oral intake of 4 g of whey protein per hour (PULSE, n = 10), 28 g of whey protein at 0 h and 12 g of whey protein at 7 h postexercise (BOLUS, n = 10), or 4 g of maltodextrin per hour (placebo, n = 10). Quadriceps muscle biopsies were taken at 0, 3, 7, and 10 h postexercise from the resting and the exercised leg of each subject. Myofibrillar FSR and activity of select targets from the mechanistic target of rapamycin complex 1-signaling cascade were analyzed from the biopsies. LL-RE increased myofibrillar FSR compared with the resting leg throughout the 10-h postexercise period. Phosphorylated (T308) AKT expression increased in the exercised leg immediately after exercise. This increase persisted in the placebo group only. Levels of phosphorylated (T37/46) eukaryotic translation initiation factor 4E-binding protein 1 increased throughout the postexercise period in the exercised leg in the placebo and BOLUS groups and peaked at 7 h. In all three groups, phosphorylated (T56) eukaryotic elongation factor 2 decreased in response to LL-RE. We conclude that resistance exercise at only 16% of 1 RM increased myofibrillar FSR, irrespective of nutrient type and feeding pattern, which indicates an anabolic effect of LL-RE in elderly individuals. This finding was supported by increased signaling for translation initiation and translation elongation in response to LL-RE.
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Affiliation(s)
- Jakob Agergaard
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark;
- Department of Physical Therapy, University of Utah, Salt Lake City, Utah
| | - Jacob Bülow
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacob K Jensen
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Micah J Drummond
- Department of Physical Therapy, University of Utah, Salt Lake City, Utah
| | - Peter Schjerling
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Scheike
- Department of Biostatistics, Institute of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; and
| | - Anja Serena
- Arla Foods Ingredients Group P/S, Viby, Denmark
| | - Lars Holm
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Shad BJ, Thompson JL, Breen L. Does the muscle protein synthetic response to exercise and amino acid-based nutrition diminish with advancing age? A systematic review. Am J Physiol Endocrinol Metab 2016; 311:E803-E817. [PMID: 27555299 DOI: 10.1152/ajpendo.00213.2016] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 08/16/2016] [Indexed: 01/06/2023]
Abstract
The precise role of age-related muscle anabolic resistance in the progression of sarcopenia and functional decline in older individuals is unclear. The present aim was to assess whether the muscle protein synthesis (MPS) response to acute exercise (endurance or resistance) and/or amino acid-based nutrition is attenuated in older compared with young individuals. A systematic review was conducted on studies that directly examined the influence of age on the MPS response to exercise and/or amino acid-based nutrition. Each study arm was synthesized and reported as providing sufficient or insufficient "evidence of age-related muscle anabolic resistance". Subsequently, three models were established to compare age-related differences in the MPS response to 1) exercise alone, 2) amino acid-based nutrition alone, or 3) the combination of exercise and amino acid-based nutrition. Following exercise alone, 8 of the 17 study arms provided sufficient evidence of age-related muscle anabolic resistance, while in response to amino acid-based nutrition alone, 8 of the 21 study arms provided sufficient evidence of age-related muscle anabolic resistance. When exercise and amino acid-based nutrition were combined, only 2 of the 10 study arms provided sufficient evidence of age-related muscle anabolic resistance. Our results highlight that optimization of exercise and amino acid-based nutrition is sufficient to induce a comparable MPS response between young and older individuals. However, the exercise volume completed and/or the amino acid/protein dose and leucine content must exceed a certain threshold to stimulate equivalent MPS rates in young and older adults, below which age-related muscle anabolic resistance may become apparent.
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Affiliation(s)
- Brandon J Shad
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, United Kingdom; and
| | - Janice L Thompson
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, United Kingdom; and
- MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Edgbaston, United Kingdom
| | - Leigh Breen
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, United Kingdom; and
- MRC-ARUK Centre for Musculoskeletal Ageing Research, University of Birmingham, Edgbaston, United Kingdom
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Bülow J, Agergaard J, Kjaer M, Holm L, Reitelseder S. No additional effect of different types of physical activity on 10-hour muscle protein synthesis in elderly men on a controlled energy- and protein-sufficient diet. Exp Gerontol 2016; 79:16-25. [DOI: 10.1016/j.exger.2016.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 03/07/2016] [Accepted: 03/11/2016] [Indexed: 12/19/2022]
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Moberg M, Apró W, Ekblom B, van Hall G, Holmberg HC, Blomstrand E. Activation of mTORC1 by leucine is potentiated by branched-chain amino acids and even more so by essential amino acids following resistance exercise. Am J Physiol Cell Physiol 2016; 310:C874-84. [PMID: 27053525 DOI: 10.1152/ajpcell.00374.2015] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 03/31/2016] [Indexed: 12/31/2022]
Abstract
Protein synthesis is stimulated by resistance exercise and intake of amino acids, in particular leucine. Moreover, activation of mammalian target of rapamycin complex 1 (mTORC1) signaling by leucine is potentiated by the presence of other essential amino acids (EAA). However, the contribution of the branched-chain amino acids (BCAA) to this effect is yet unknown. Here we compare the stimulatory role of leucine, BCAA, and EAA ingestion on anabolic signaling following exercise. Accordingly, eight trained volunteers completed four sessions of resistance exercise during which they ingested either placebo, leucine, BCAA, or EAA (including the BCAA) in random order. Muscle biopsies were taken at rest, immediately after exercise, and following 90 and 180 min of recovery. Following 90 min of recovery the activity of S6 kinase 1 (S6K1) was greater than at rest in all four trials (Placebo<Leucine<BCAA<EAA; P < 0.05 time × supplement), with a ninefold increase in the EAA trial. At this same time point, phosphorylation of eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) at Thr(37/46) was unaffected by supplementation, while that of Thr(46) alone exhibited a pattern similar to that of S6K1, being 18% higher with EAA than BCAA. However, after 180 min of recovery this difference between EAA and BCAA had disappeared, although with both these supplements the increases were still higher than with leucine (40%, P < 0.05) and placebo (100%, P < 0.05). In summary, EAA ingestion appears to stimulate translation initiation more effectively than the other supplements, although the results also suggest that this effect is primarily attributable to the BCAA.
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Affiliation(s)
- Marcus Moberg
- Åstrand Laboratory, Swedish School of Sport and Health Sciences, Stockholm, Sweden;
| | - William Apró
- Åstrand Laboratory, Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Björn Ekblom
- Åstrand Laboratory, Swedish School of Sport and Health Sciences, Stockholm, Sweden
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Rigshopitalet and Department of Biomedical Sciences, Rigshospitalet, University of Copenhagen, Copenhagen Denmark
| | - Hans-Christer Holmberg
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden; and
| | - Eva Blomstrand
- Åstrand Laboratory, Swedish School of Sport and Health Sciences, Stockholm, Sweden; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Burd NA, Cermak NM, Kouw IWK, Gorissen SH, Gijsen AP, van Loon LJC. The use of doubly labeled milk protein to measure postprandial muscle protein synthesis rates in vivo in humans. J Appl Physiol (1985) 2014; 117:1363-70. [PMID: 25277738 DOI: 10.1152/japplphysiol.00411.2014] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We aimed to determine the impact of precursor pool dilution on the assessment of postprandial myofibrillar protein synthesis rates (MPS). A Holstein dairy cow was infused with large amounts of L-[1-(13)C]phenylalanine and L-[1-(13)C]leucine, and the milk was collected and fractionated. The enrichment levels in the casein were 38.7 and 9.3 mole percent excess, respectively. In a subsequent human experiment, 11 older men (age: 71 ± 1 y, body mass index: 26 ± 0.1 kg·m(-2)) received a primed constant infusion of L-[ring-(2)H5]phenylalanine and L-[1-(13)C]leucine. Blood and muscle samples were collected before and after the ingestion of 20-g doubly labeled casein to assess postprandial MPS based on the 1) constant tracer infusion of L-[ring-(2)H5]phenylalanine, 2) ingestion of intrinsically L-[1-(13)C]phenylalanine-labeled casein, and 3) constant infusion of L-[1-(13)C]leucine in combination with the ingestion of intrinsically L-[1-(13)C]leucine-labeled casein. Postprandial MPS was increased (P < 0.05) after protein ingestion (∼70% above postabsorptive values) based on the L-[1-(13)C]leucine tracer. There was no significant stimulation of postprandial MPS (∼27% above postabsorptive values) when the calculated fractional synthesis rate was based on the L-[ring-(2)H5]phenylalanine (P = 0.2). Comparisons of postprandial MPS based on the primed continuous infusion of L-[1-(13)C]leucine or the ingestion of intrinsically L-[1-(13)C]phenylalanine-labeled casein protein demonstrated differences compared with the primed continuous infusion of L-[ring-(2)H5]phenylalanine (P > 0.05). Our findings confirm that the postprandial MPS assessed using the primed continuous tracer infusion approach may differ if tracer steady-state conditions in the precursor pools are perturbed. The use of intrinsically doubly labeled protein provides a method to study the metabolic fate of the ingested protein and the subsequent postprandial MPS response.
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Affiliation(s)
- Nicholas A Burd
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Naomi M Cermak
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Imre W K Kouw
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Stefan H Gorissen
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Annemie P Gijsen
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
| | - Luc J C van Loon
- NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands
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