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Dideriksen K, Reitelseder S, Boesen AP, Zillmer M, Agergaard J, Kjaer M, Holm L. Lower basal and postprandial muscle protein synthesis after 2 weeks single-leg immobilization in older men: No protective effect of anti-inflammatory medication. Physiol Rep 2024; 12:e15958. [PMID: 38406891 PMCID: PMC10895449 DOI: 10.14814/phy2.15958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 02/05/2024] [Accepted: 02/05/2024] [Indexed: 02/27/2024] Open
Abstract
Muscle inactivity may reduce basal and postprandial muscle protein synthesis (MPS) rates in humans. Anti-inflammatory treatment alleviates the MPS impairments in younger individuals. The present study explored the influence of nonsteroidal anti-inflammatory drugs (NSAIDs) upon MPS during a period of inactivity in older humans. Eighteen men (age 60-80 years) were allocated to ibuprofen (1200 mg/day, Ibu) or control (Plc) groups. One lower limb was cast immobilized for 2 weeks. Postabsorptive and postprandial MPS was measured before and after the immobilization by L-[ring-13 C6 ]-phenylalanine infusion. The protein expression of select anabolic signaling molecules was investigated by western blot. Basal (0.038 ± 0.002%/h and 0.039 ± 0.005%/h, Plc and Ibu, respectively) and postprandial (0.064 ± 0.004%/h and 0.067 ± 0.010%/h, Plc and Ibu, respectively) MPS rate were higher pre-immobilization compared to basal (0.019 ± 0.005%/h and 0.020 ± 0.010%/h, Plc and Ibu, respectively) and postprandial (0.033 ± 0.005%/h and 0.037 ± 0.006%/h, Plc and Ibu, respectively) MPS rate post-immobilization (p < 0.001). NSAID treatment did not affect the suppression of MPS (p > 0.05). The anabolic signaling were in general reduced after immobilization (p < 0.05). These changes were unaffected by NSAID treatment (p > 0.05). Basal and postprandial MPS dropped markedly after 2 weeks of lower limb immobilization. NSAID treatment neither influenced the reduction in MPS nor the anabolic signaling after immobilization in healthy older individuals.
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Affiliation(s)
- K Dideriksen
- 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
| | - S Reitelseder
- 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
- Faculty of Health and Medical Sciences, Institute of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - A P Boesen
- 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
| | - M Zillmer
- 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
| | - J Agergaard
- 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
| | - M Kjaer
- 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
| | - L Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Faculty of Health and Medical Sciences, Institute of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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Mertz KH, Reitelseder S, Rasmussen MA, Bülow J, Højfeldt G, Jensen M, Hjulmand M, Lindberg J, Kramer MU, Bechshøft R, Holm L. Changes in Muscle Mass and Strength During Follow-Up After One-Year Resistance Training Interventions in Older Adults. J Strength Cond Res 2023; 37:2064-2070. [PMID: 37463344 DOI: 10.1519/jsc.0000000000004517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
ABSTRACT Mertz, KH, Reitelseder, S, Rasmussen, MA, Bülow, J, Højfeldt, G, Jensen, M, Hjulmand, M, Lindberg, J, Kramer, MU, Bechshøft, R, and Holm, L. Changes in muscle mass and strength during follow-up after one-year resistance training interventions in older adults. J Strength Cond Res 37(10): 2064-2070, 2023-The aim of this study was to investigate if home-based resistance training compared with center-based resistance training was associated with better preservation of muscle mass and strength in older individuals, 6 months after the interventions ended. One hundred four healthy older individuals (>65 years) who had completed 1 year of either home-based light-intensity training with daily whey protein supplementation (LITW), center-based heavy resistance training with whey protein supplementation (HRTW), or daily whey protein supplementation alone (WHEY) returned for follow-up measurement 6 months after the interventions. Measures of muscle mass, strength, and power were assessed at the end of intervention as well as at follow-up. Furthermore, we compared changes in these parameters between subjects who continued resistance training (≥1 weekly training session) during follow-up (CONT) with those who stopped (STOP). Resistance training continuation during follow-up did not differ between HRTW and LITW (41 vs. 41%, P = 1.0) but was higher for both groups compared with WHEY (18%, P = 0.04-0.05). However, no between-group differences were observed between LITW/HRTW/WHEY in changes in muscle mass, strength, or power during follow-up. STOP was associated with a poorer preservation of quadriceps cross-sectional area compared with CONT (-1.7 cm 2 [-0.4 to -3.0], P = 0.01, effect size: 0.79). No effect of training continuation was observed on changes in muscle strength and power. In conclusion, maintenance of muscle mass and strength is not superior after home-based resistance training compared with center-based training. However, training continuation seems crucial for the maintenance of muscle mass, irrespective of the training intervention.
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Affiliation(s)
- Kenneth H Mertz
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Søren Reitelseder
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Morten A Rasmussen
- Department of Food Science, University of Copenhagen, Copenhagen, Denmark; and
| | - Jacob Bülow
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Grith Højfeldt
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Mikkel Jensen
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Morten Hjulmand
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Jonas Lindberg
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Mathilde U Kramer
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
| | - Rasmus Bechshøft
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Denmark
| | - Lars Holm
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, 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, United Kingdom
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Cui M, Trimigno A, Castro-Mejía JL, Reitelseder S, Bülow J, Bechshøft RL, Nielsen DS, Holm L, Engelsen SB, Khakimov B. Human Fecal Metabolome Reflects Differences in Body Mass Index, Physical Fitness, and Blood Lipoproteins in Healthy Older Adults. Metabolites 2021; 11:717. [PMID: 34822375 PMCID: PMC8620003 DOI: 10.3390/metabo11110717] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/12/2021] [Accepted: 10/15/2021] [Indexed: 12/12/2022] Open
Abstract
This study investigated how body mass index (BMI), physical fitness, and blood plasma lipoprotein levels are related to the fecal metabolome in older adults. The fecal metabolome data were acquired using proton nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry on 163 healthy older adults (65-80 years old, 80 females and 83 males). Overweight and obese subjects (BMI ≥ 27) showed higher levels of fecal amino acids (AAs) (valine, alanine, and phenylalanine) compared to normal-weight subjects (BMI ≤ 23.5). Adults classified in the high-fitness group displayed slightly lower concentrations of fecal short-chain fatty acids, propionic acid, and AAs (methionine, leucine, glutamic acid, and threonine) compared to the low-fitness group. Subjects with lower levels of cholesterol in low-density lipoprotein particles (LDLchol, ≤2.6 mmol/L) displayed higher fecal levels of valine, glutamic acid, phenylalanine, and lactic acid, while subjects with a higher level of cholesterol in high-density lipoprotein particles (HDLchol, ≥2.1 mmol/L) showed lower fecal concentration of isovaleric acid. The results from this study suggest that the human fecal metabolome, which primarily represents undigested food waste and metabolites produced by the gut microbiome, carries important information about human health and should be closely integrated to other omics data for a better understanding of the role of the gut microbiome and diet on human health and metabolism.
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Affiliation(s)
- Mengni Cui
- Chemometrics and Analytical Technology Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (M.C.); (A.T.)
| | - Alessia Trimigno
- Chemometrics and Analytical Technology Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (M.C.); (A.T.)
| | - Josue L. Castro-Mejía
- Food Microbiology & Fermentation Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (J.L.C.-M.); (D.S.N.)
| | - Søren Reitelseder
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg and Frederiksberg Hospital, Nielsine Nielsens Vej 11, 2400 Copenhagen, Denmark; (S.R.); (J.B.); (R.L.B.); (L.H.)
| | - Jacob Bülow
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg and Frederiksberg Hospital, Nielsine Nielsens Vej 11, 2400 Copenhagen, Denmark; (S.R.); (J.B.); (R.L.B.); (L.H.)
| | - Rasmus Leidesdorff Bechshøft
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg and Frederiksberg Hospital, Nielsine Nielsens Vej 11, 2400 Copenhagen, Denmark; (S.R.); (J.B.); (R.L.B.); (L.H.)
| | - Dennis Sandris Nielsen
- Food Microbiology & Fermentation Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (J.L.C.-M.); (D.S.N.)
| | - Lars Holm
- Institute of Sports Medicine, Department of Orthopedic Surgery, Bispebjerg and Frederiksberg Hospital, Nielsine Nielsens Vej 11, 2400 Copenhagen, Denmark; (S.R.); (J.B.); (R.L.B.); (L.H.)
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Søren Balling Engelsen
- Chemometrics and Analytical Technology Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (M.C.); (A.T.)
| | - Bekzod Khakimov
- Chemometrics and Analytical Technology Section, Department of Food Science University of Copenhagen Rolighedsvej 26, 1958 Frederiksberg C, Denmark; (M.C.); (A.T.)
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Reitelseder S, Bülow J, Holm L. Divergent Anabolic Response to Exercise in Young and Older Adult Men-Dependency on Time Frame of Measurement. J Gerontol A Biol Sci Med Sci 2021; 76:996-999. [PMID: 33539523 PMCID: PMC8266534 DOI: 10.1093/gerona/glab040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Indexed: 01/08/2023] Open
Abstract
Older adults’ skeletal muscle has shown to be less responsive to anabolic stimuli as compared to young both in vitro, in short and controlled in vivo settings and in long-term training studies. However, to translate controlled mechanistic findings to long-term adaptations intermediate measures allowing daily life routines with regard to activity and diet would be useful to evaluate physiological interventions. The purpose of this study was to investigate the exercise effect in young and older adults with 2 independent methods to measure muscle protein synthesis rate. Healthy young and old men were recruited to the study protocol where myofibrillar fractional synthesis rate was measured during 2 days allowing normal activities of daily living with D2O-labeled alanine and during 4 hours in the overnight fasted state with [13C6]phenylalanine infusion. During this period 1 leg completed an exercise session every day (exercise leg) while the contralateral leg was kept inactive (normal leg). Both legs were used for activities of daily living. Two-day myofibrillar fractional synthesis rate was significantly higher in the exercise leg in both young and old as compared to normal leg with no age difference. The 4-hour overnight fasted myofibrillar fractional synthesis rate showed that only young exercise leg was significantly higher than normal leg. The present findings support the notion that anabolic resistance exists in the skeletal muscle of healthy older men when evaluated in controlled settings. However, this response is not as clear when measured during daily life where variance is greater, which calls for further investigations in larger cohorts.
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Affiliation(s)
- Søren Reitelseder
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Jacob Bülow
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Denmark
| | - Lars Holm
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Denmark.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, UK
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Mertz KH, Reitelseder S, Bechshoeft R, Bulow J, Højfeldt G, Jensen M, Schacht SR, Lind MV, Rasmussen MA, Mikkelsen UR, Tetens I, Engelsen SB, Nielsen DS, Jespersen AP, Holm L. The effect of daily protein supplementation, with or without resistance training for 1 year, on muscle size, strength, and function in healthy older adults: A randomized controlled trial. Am J Clin Nutr 2021; 113:790-800. [PMID: 33564844 DOI: 10.1093/ajcn/nqaa372] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 11/16/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Protein supplementation alone or combined with resistance training has been proposed to be effective in counteracting age-related losses of muscle mass and strength. OBJECTIVES To investigate the effect of protein supplementation alone or combined with light-intensity or heavy-load resistance exercise on muscle size, strength, and function in older adults. METHODS In a 1-y randomized controlled trial, 208 healthy older adults (>65 y) were randomly assigned to 1 of 5 interventions: 1) carbohydrate supplementation (CARB); 2) collagen protein supplementation (COLL); 3) whey protein supplementation (WHEY); 4) light-intensity resistance training 3-5 times/wk with whey protein supplementation (LITW); and 5) heavy resistance training 3 times weekly with whey protein supplementation (HRTW). Protein supplements contained 20 g protein + 10 g carbohydrate, whereas CARB contained 30 g of carbohydrates. All intervention groups received the supplement twice daily. The primary outcome was change in the quadriceps cross-sectional area (qCSA). Secondary outcomes included measures of lower extremity strength and power, functional capabilities, and body composition. RESULTS There were 184 participants who completed the study. COLL and WHEY did not affect any measured parameter compared to CARB. Compared to WHEY, HRTW improved the qCSA size (between-group difference, +1.68 cm2; 95% CI, +0.41 to +2.95 cm2; P = 0.03), as well as dynamic (+18.4 Nm; 95% CI, +10.1 to +26.6 Nm; P < 10-4) and isometric knee extensor strength (+23.9 Nm; 95% CI, +14.2 to +33.6 Nm; P < 10-5). LITW did not improve the qCSA size, but increased dynamic knee extensor strength compared to WHEY (+13.7 Nm; 95% CI, +5.3 and +22.1 Nm; P = 0.01). CONCLUSIONS Recommending protein supplementation as a stand-alone intervention for healthy older individuals seems ineffective in improving muscle mass and strength. Only HRTW was effective in both preserving muscle mass and increasing strength. Thus, we recommend that future studies investigate strategies to increase long-term compliance to heavy resistance exercise in healthy older adults. This trial was registered at clinicaltrials.gov as NCT02034760.
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Affiliation(s)
- Kenneth H Mertz
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rasmus Bechshoeft
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jacob Bulow
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Grith Højfeldt
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Mikkel Jensen
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Simon R Schacht
- Vitality Centre for Good Older Lives, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Mads Vendelbo Lind
- Vitality Centre for Good Older Lives, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Morten A Rasmussen
- Department of Food Science, University of Copenhagen, Copenhagen, Denmark
| | | | - Inge Tetens
- Vitality Centre for Good Older Lives, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Søren B Engelsen
- Department of Food Science, University of Copenhagen, Copenhagen, Denmark
| | - Dennis S Nielsen
- Department of Food Science, University of Copenhagen, Copenhagen, Denmark
| | - Astrid P Jespersen
- Copenhagen Center for Health Research in the Humanities, Saxo-Institute, University of Copenhagen, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine, Department of Orthopaedic Surgery M, 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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Jessen S, Reitelseder S, Kalsen A, Kreiberg M, Onslev J, Gad A, Ørtenblad N, Backer V, Holm L, Bangsbo J, Hostrup M. β 2-Adrenergic agonist salbutamol augments hypertrophy in MHCIIa fibers and sprint mean power output but not muscle force during 11 weeks of resistance training in young men. J Appl Physiol (1985) 2020; 130:617-626. [PMID: 33357007 DOI: 10.1152/japplphysiol.00553.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this study, we examined the effect of β2-agonist salbutamol at oral doses during a period of resistance training on sprint performance, quadriceps contractile function, skeletal muscle hypertrophy, fiber type composition, maximal activity of enzymes of importance for anaerobic energy turnover, and sarcoplasmic reticulum Ca2+ handling in young men. Twenty-six men (23 ± 2 yr; means ± SD) were randomized to daily intake of oral salbutamol (16 mg/day; RES+SAL) or placebo (RES) during 11 wk of full-body resistance training 3 times/wk. Mean power output during 10-s maximal cycling increased more (P = 0.027) in RES+SAL (+12%) than in RES (+7%), whereas peak power output increased similarly (RES+SAL: +8%; RES: +7%; P = 0.400). Quadriceps dynamic peak torque and maximal voluntary isometric torque increased by 13 and 14% (P ≤ 0.001) in RES+SAL and 13 and 13% (P ≤ 0.001) in RES, respectively. Myosin heavy-chain (MHC) isoform distribution transitioned from MHCI and MHCIIx toward MHCIIa in RES+SAL (P = 0.002), but not in RES (P = 0.323). MHCIIa cross-sectional-area increased more (P = 0.040) in RES+SAL (+35%) than RES (+21%). Sarcoplasmic reticulum Ca2+ release rate increased in both groups (RES+SAL: +9%, P = 0.048; RES: +13%, P = 0.008), whereas Ca2+-uptake rate increased only in RES (+12%, P = 0.022) but was not different from the nonsignificant change in RES+SAL (+2%, P = 0.484). Maximal activity of lactate dehydrogenase increased only in RES+SAL (+13%, P = 0.008). Muscle content of the dihydropyridine receptor, ryanodine receptor 1, and sarcoplasmic reticulum Ca2+-ATPase isoform 1 and 2 did not change with the intervention in either group (P ≥ 0.100). These observations indicate that the enhancement of sprint mean power output induced by salbutamol is at least partly attributed to greater hypertrophy of MHCIIa fibers and transition toward the MHCIIa isoform.NEW & NOTEWORTHY Here, we show that daily oral treatment with selective β2-agonist salbutamol induces muscle fiber isoform transition from myosin-heavy-chain (MHC)-I toward MHCIIa and augments hypertrophy of MHCIIa fibers during a period of resistance training. Compared with placebo, salbutamol enhanced sprint mean power output, whereas peak power output and measures of muscle strength increased similarly during the resistance training period despite augmented hypertrophy with salbutamol. Thus, salbutamol is a muscle anabolic drug that can enhance sprint ability adaptations to resistance training.
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Affiliation(s)
- Søren Jessen
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Anders Kalsen
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kreiberg
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Johan Onslev
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Anders Gad
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Vibeke Backer
- Centre for Physical Activity Research, Rigshospitalet and University of Copenhagen, Copenhagen Denmark.,Department of Otorhinolaryngology, Head and Neck Surgery & Audiology, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jens Bangsbo
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Morten Hostrup
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Reitelseder S, Tranberg B, Agergaard J, Dideriksen K, Højfeldt G, Merry ME, Storm AC, Poulsen KR, Hansen ET, van Hall G, Lund P, Holm L. Phenylalanine stable isotope tracer labeling of cow milk and meat and human experimental applications to study dietary protein-derived amino acid availability. Clin Nutr 2020; 39:3652-3662. [PMID: 32334880 DOI: 10.1016/j.clnu.2020.03.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 02/25/2020] [Accepted: 03/20/2020] [Indexed: 11/25/2022]
Abstract
BACKGROUND & AIMS Availability of dietary protein-derived amino acids (AA) is an important determinant for their utilization in metabolism and for protein synthesis. Intrinsic labeling of protein is the only method to directly trace availability and utilization. The purpose of the present study was to produce labeled milk and meat proteins and investigate how dietary protein-derived AA availability is affected by the protein-meal matrix. METHODS Four lactating cows were infused with L-[ring-d5]phenylalanine and one with L-[15N]phenylalanine for 72 h. Milk was collected, and three of the [d5]phenylalanine cows were subsequently slaughtered. Two human studies were performed to explore plasma AA availability properties utilizing the labeled proteins. One study compared the intake of whey protein either alone or together with carbohydrates-fat food-matrix. The other study compared the intake of meat hydrolysate with minced beef. Cow blood, milk, meat and human blood samples were collected and analyzed by mass spectrometry. RESULTS Whey and caseinate acquired label to 15-20 mol percent excess (MPE), and the meat proteins reached 0.41-0.73 MPE. The [d5]phenylalanine appeared fast in plasma and peaked 30 min after whey protein alone and meat hydrolysate intake, whereas whey protein with a food-matrix and the meat minced beef postponed the [d5]phenylalanine peak until 2 and 1 h, respectively. CONCLUSIONS Phenylalanine stable isotope-labeled milk and meat were produced and proved a valuable tool to investigate AA absorption characteristics. Dietary protein in food-matrices showed delayed postprandial plasma AA availability as compared to whey protein alone and meat hydrolysate.
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Affiliation(s)
- Søren Reitelseder
- 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.
| | - Britt Tranberg
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
| | - Kasper Dideriksen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
| | - Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
| | - Marie Emily Merry
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.
| | - Adam C Storm
- Department of Animal Science, Aarhus University Foulum, Aarhus University, Aarhus, 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.
| | - Peter Lund
- Department of Animal Science, Aarhus University Foulum, Aarhus University, Aarhus, Denmark.
| | - Lars Holm
- 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; School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK.
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9
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Castro‐Mejía JL, Khakimov B, Krych Ł, Bülow J, Bechshøft RL, Højfeldt G, Mertz KH, Garne ES, Schacht SR, Ahmad HF, Kot W, Hansen LH, Perez‐Cueto FJA, Lind MV, Lassen AJ, Tetens I, Jensen T, Reitelseder S, Jespersen AP, Holm L, Engelsen SB, Nielsen DS. Physical fitness in community-dwelling older adults is linked to dietary intake, gut microbiota, and metabolomic signatures. Aging Cell 2020; 19:e13105. [PMID: 31967716 PMCID: PMC7059135 DOI: 10.1111/acel.13105] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/28/2019] [Accepted: 12/30/2019] [Indexed: 12/13/2022] Open
Abstract
When humans age, changes in body composition arise along with lifestyle-associated disorders influencing fitness and physical decline. Here we provide a comprehensive view of dietary intake, physical activity, gut microbiota (GM), and host metabolome in relation to physical fitness of 207 community-dwelling subjects aged +65 years. Stratification on anthropometric/body composition/physical performance measurements (ABPm) variables identified two phenotypes (high/low-fitness) clearly linked to dietary intake, physical activity, GM, and host metabolome patterns. Strikingly, despite a higher energy intake high-fitness subjects were characterized by leaner bodies and lower fasting proinsulin-C-peptide/blood glucose levels in a mechanism likely driven by higher dietary fiber intake, physical activity and increased abundance of Bifidobacteriales and Clostridiales species in GM and associated metabolites (i.e., enterolactone). These factors explained 50.1% of the individual variation in physical fitness. We propose that targeting dietary strategies for modulation of GM and host metabolome interactions may allow establishing therapeutic approaches to delay and possibly revert comorbidities of aging.
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Affiliation(s)
| | - Bekzod Khakimov
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
| | - Łukasz Krych
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
| | - Jacob Bülow
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
| | - Rasmus L. Bechshøft
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagen NDenmark
| | - Grith Højfeldt
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
| | - Kenneth H. Mertz
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
| | - Eva Stahl Garne
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagen NDenmark
| | - Simon R. Schacht
- Department of Nutrition, Exercise and SportsUniversity of CopenhagenFrederiksberg CDenmark
| | - Hajar F. Ahmad
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
- Faculty of Industrial Science and TechnologyIndustrial Biotechnology ProgramUniversiti Malaysia PahangPahangMalaysia
| | - Witold Kot
- Department of Plant and Environmental SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | - Lars H. Hansen
- Department of Plant and Environmental SciencesUniversity of CopenhagenFrederiksberg CDenmark
| | | | - Mads V. Lind
- Department of Nutrition, Exercise and SportsUniversity of CopenhagenFrederiksberg CDenmark
| | - Aske J. Lassen
- Copenhagen Center for Health Research in the HumanitiesThe SAXO InstituteUniversity of CopenhagenCopenhagen SVDenmark
| | - Inge Tetens
- Department of Nutrition, Exercise and SportsUniversity of CopenhagenFrederiksberg CDenmark
| | - Tenna Jensen
- Copenhagen Center for Health Research in the HumanitiesThe SAXO InstituteUniversity of CopenhagenCopenhagen SVDenmark
| | - Søren Reitelseder
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagen NDenmark
| | - Astrid P. Jespersen
- Copenhagen Center for Health Research in the HumanitiesThe SAXO InstituteUniversity of CopenhagenCopenhagen SVDenmark
| | - Lars Holm
- Department of Orthopedic Surgery MBispebjerg HospitalCopenhagen NVDenmark
- Department of Biomedical SciencesUniversity of CopenhagenCopenhagen NDenmark
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUK
| | - Søren B. Engelsen
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
| | - Dennis S. Nielsen
- Department of Food ScienceUniversity of CopenhagenFrederiksberg CDenmark
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10
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Schacht SR, Lind MV, Mertz KH, Bülow J, Bechshøft R, Højfeldt G, Schucany A, Hjulmand M, Sidoli C, Andersen SB, Jensen M, Reitelseder S, Holm L, Tetens I. Development of a Mobility Diet Score (MDS) and Associations With Bone Mineral Density and Muscle Function in Older Adults. Front Nutr 2019; 6:114. [PMID: 31552255 PMCID: PMC6738326 DOI: 10.3389/fnut.2019.00114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 07/11/2019] [Indexed: 01/19/2023] Open
Abstract
Introduction: Reduced bone mineral density (BMD) and muscle function is associated with increased risk of multiple health related issues. Diet may play a role in sustaining BMD and muscle function throughout old age, but much is still to be learned with regards to which specific food groups and dietary patterns that are important for such outcomes. The aim of the current study was to identify food groups important for both BMD and muscle function. Methods: A narrative review was performed on studies published on dietary patterns and their association with BMD and muscle function, respectively. Based on these findings, two dietary indices were constructed characterizing food groups associated with BMD and muscle function, respectively. Associations between adherence to these indices and BMD and muscle function were then investigated in a population of older community-dwelling Danes. Food groups found to be associated with both BMD and muscle function in our study population were suggested for inclusion into a common dietary index named the Mobility Diet Score. Results: In contrast to previous studies, adherence to a dietary index based on foods previously linked to BMD could not be established as important for BMD in our study population of 184 older individuals (53.3% men). We found that adhering to a dietary index characterized by higher intakes of whole grains, dairy products, fish, legumes, nuts, fruit, and vegetables is associated with faster 400 m walking speeds and an increased number of chair stands measured over a 30 s time period. Since no food group could be established as important for both BMD and muscle function in our study population, a Mobility Diet Score could not be established. However, based on our narrative review, the food groups commonly associated with improved BMD and muscle function are similar. Conclusion: Adherence to a dietary index characterized by high intakes of whole grains, dairy products, fish, legumes, nuts, fruit, and vegetables was not found to be associated with BMD in a group of community-dwelling older Danes. However, our results indicate that the adherence to such foods could be important in sustaining physical function in older individuals.
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Affiliation(s)
- Simon Rønnow Schacht
- Department of Nutrition, Exercise and Sports, Vitality - Centre for Good Older Lives, University of Copenhagen, Copenhagen, Denmark
| | - Mads Vendelbo Lind
- Department of Nutrition, Exercise and Sports, Vitality - Centre for Good Older Lives, University of Copenhagen, Copenhagen, Denmark
| | - Kenneth Hudlebusch Mertz
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jacob Bülow
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Rasmus Bechshøft
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Grith Højfeldt
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Aide Schucany
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Morten Hjulmand
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Chiara Sidoli
- School of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Søren Binder Andersen
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Mikkel Jensen
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Søren Reitelseder
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Holm
- Department of Orthopaedic Surgery M, Institute of Sports Medicine, 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
| | - Inge Tetens
- Department of Nutrition, Exercise and Sports, Vitality - Centre for Good Older Lives, University of Copenhagen, Copenhagen, Denmark
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11
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Holm L, Dideriksen K, Nielsen RH, Doessing S, Bechshoeft RL, Højfeldt G, Moberg M, Blomstrand E, Reitelseder S, van Hall G. An exploration of the methods to determine the protein-specific synthesis and breakdown rates in vivo in humans. Physiol Rep 2019; 7:e14143. [PMID: 31496135 PMCID: PMC6732504 DOI: 10.14814/phy2.14143] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 01/02/2023] Open
Abstract
The present study explores the methods to determine human in vivo protein-specific myofibrillar and collagenous connective tissue protein fractional synthesis and breakdown rates. We found that in human myofibrillar proteins, the protein-bound tracer disappearance method to determine the protein fractional breakdown rate (FBR) (via 2 H2 O ingestion, endogenous labeling of 2 H-alanine that is incorporated into proteins, and FBR quantified by its disappearance from these proteins) has a comparable intrasubject reproducibility (range: 0.09-53.5%) as the established direct-essential amino acid, here L-ring-13 C6 -phenylalanine, incorporation method to determine the muscle protein fractional synthesis rate (FSR) (range: 2.8-56.2%). Further, the determination of the protein breakdown in a protein structure with complex post-translational processing and maturation, exemplified by human tendon tissue, was not achieved in this experimentation, but more investigation is encouraged to reveal the possibility. Finally, we found that muscle protein FBR measured with an essential amino acid tracer prelabeling is inappropriate presumably because of significant and prolonged intracellular recycling, which also may become a significant limitation for determination of the myofibrillar FSR when repeated infusion trials are completed in the same participants.
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Affiliation(s)
- Lars Holm
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- School of Sport, Exercise and Rehabilitation SciencesUniversity of BirminghamBirminghamUnited Kingdom
| | - Kasper Dideriksen
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
| | - Rie H. Nielsen
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
| | - Simon Doessing
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
| | - Rasmus L. Bechshoeft
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Grith Højfeldt
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
| | - Marcus Moberg
- Aastrand LaboratorySwedish School of Sport and Health SciencesStockholmSweden
| | - Eva Blomstrand
- Aastrand LaboratorySwedish School of Sport and Health SciencesStockholmSweden
- Department of Physiology and PharmacologyKarolinska InstitutetStockholmSweden
| | - Søren Reitelseder
- Institute of Sports Medicine and Department of Orthopedic Surgery MBispebjerg HospitalCopenhagenDenmark
| | - Gerrit van Hall
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Clinical Metabolomics Core FacilityDepartment of Clinical Biochemistry, RigshospitaletCopenhagenDenmark
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12
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Mertz KH, Reitelseder S, Jensen M, Lindberg J, Hjulmand M, Schucany A, Binder Andersen S, Bechshoeft RL, Jakobsen MD, Bieler T, Beyer N, Lindberg Nielsen J, Aagaard P, Holm L. Influence of between-limb asymmetry in muscle mass, strength, and power on functional capacity in healthy older adults. Scand J Med Sci Sports 2019; 29:1901-1908. [PMID: 31353627 DOI: 10.1111/sms.13524] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 07/05/2019] [Accepted: 07/24/2019] [Indexed: 12/25/2022]
Abstract
PURPOSE Numerous daily tasks such as walking and rising from a chair involve bilateral lower limb movements. During such tasks, lower extremity function (LEF) may be compromised among older adults. LEF may be further impaired due to high degrees of between-limb asymmetry. The present study investigated the prevalence of between-limb asymmetry in muscle mass, strength, and power in a cohort of healthy older adults and examined the influence of between-limb asymmetry on LEF. METHODS Two hundred and eight healthy older adults (mean age 70.2 ± 3.9 years) were tested for LEF (400 m walking and 30-seconds chair stand). Furthermore, maximal isometric and dynamic knee extensor strength, leg extensor power, and lower limb lean tissue mass (LTM) were obtained unilaterally. RESULTS Mean between-limb asymmetry in maximal muscle strength and power ranged between 10% and 13%, whereas LTM asymmetry was 3 ± 2.3%. Asymmetry in dynamic knee extensor strength was larger for women compared with men (15.0 ± 11.8% vs 11.1 ± 9.5%; P = .005) Leg strength and power were positively correlated with LEF (r2 = .43-.46, P < .001). The weakest leg was not a stronger predictor of LEF than the strongest leg. Between-limb asymmetry in LTM and isometric strength was negatively associated with LEF (LTM; r2 = .12, P = .005, isometric peak torque; r2 = 0.40, P = .03.) but dynamic strength and power were not. CONCLUSION The present study supports the notion that in order to improve or maintain LEF, healthy older adults should participate in training interventions that increase muscle strength and power, whereas the effects of reducing between-limb asymmetry in these parameters might be of less importance.
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Affiliation(s)
- Kenneth H Mertz
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mikkel Jensen
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Jonas Lindberg
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Morten Hjulmand
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Aide Schucany
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Søren Binder Andersen
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Rasmus L Bechshoeft
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark
| | - Markus D Jakobsen
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Theresa Bieler
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Physical and Occupational Therapy, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Nina Beyer
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Department of Physical and Occupational Therapy, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Jakob Lindberg Nielsen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Per Aagaard
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen and Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,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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13
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Svane MS, Bojsen-Møller KN, Martinussen C, Dirksen C, Madsen JL, Reitelseder S, Holm L, Rehfeld JF, Kristiansen VB, van Hall G, Holst JJ, Madsbad S. Postprandial Nutrient Handling and Gastrointestinal Hormone Secretion After Roux-en-Y Gastric Bypass vs Sleeve Gastrectomy. Gastroenterology 2019; 156:1627-1641.e1. [PMID: 30742833 DOI: 10.1053/j.gastro.2019.01.262] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 01/04/2019] [Accepted: 01/14/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS Sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) induce substantial weight loss and improve glycemic control in patients with type 2 diabetes, but it is not clear whether these occur via the same mechanisms. We compared absorption rates of glucose and protein, as well as profiles of gastro-entero-pancreatic hormones, in patients who had undergone SG or RYGB vs controls. METHODS We performed a cross-sectional study of 12 patients who had undergone sleeve gastrectomy, 12 patients who had undergone RYGB, and 12 individuals who had undergone neither surgery (controls), all in Denmark. Study participants were matched for body mass index, age, sex, and postoperative weight loss, and all had stable weights. They received continuous infusions of stable isotopes of glucose, glycerol, phenylalanine, tyrosine, and urea before and during a mixed meal containing labeled glucose and intrinsically phenylalanine-labeled caseinate. Blood samples were collected for 6 hours, at 10- to 60-minute intervals, and analyzed. RESULTS The systemic appearance of ingested glucose was faster after RYGB and SG vs controls; the peak glucose appearance rate was 64% higher after RYGB, and 23% higher after SG (both P < .05); the peak phenylalanine appearance rate from ingested casein was 118% higher after RYGB (P < .01), but similar between patients who had undergone SG and controls. Larger, but more transient increases in levels of plasma glucose and amino acids were accompanied by higher secretion of insulin, glucagon-like peptide 1, peptide YY, and cholecystokinin after RYGB, whereas levels of ghrelin were lower after SG, compared with RYGB and controls. Total 6-hour oral recovery of ingested glucose and protein was comparable among groups. CONCLUSIONS Postprandial glucose and protein absorption and gastro-entero-pancreatic hormone secretions differ after SG and RYGB. RYGB was characterized by accelerated absorption of glucose and amino acids, whereas protein metabolism after SG did not differ significantly from controls, suggesting that different mechanisms explain improved glycemic control and weight loss after these surgical procedures. ClinicalTrials.gov ID NCT03046186.
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Affiliation(s)
- Maria S Svane
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Kirstine N Bojsen-Møller
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Christoffer Martinussen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Carsten Dirksen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark
| | - Jan L Madsen
- Department of Clinical Physiology and Nuclear Medicine, Centre for Functional Imaging and Research, Copenhagen University Hospital Hvidovre, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark; School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, United Kingdom
| | - Jens F Rehfeld
- Department of Clinical Biochemistry, Rigshospitalet, Denmark
| | - Viggo B Kristiansen
- Department of Surgical Gastroenterology, Copenhagen University Hospital Hvidovre, Denmark
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Rigshospitalet, Denmark; Department of Biomedical Sciences, University of Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark; Department of Biomedical Sciences, University of Copenhagen, Denmark.
| | - Sten Madsbad
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Denmark; Department of Biomedical Sciences, University of Copenhagen, Denmark.
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14
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Schmedes M, Bendtsen LQ, Gomes S, Liaset B, Holst JJ, Ritz C, Reitelseder S, Sjödin A, Astrup A, Young JF, Sundekilde UK, Bertram HC. The effect of casein, hydrolyzed casein, and whey proteins on urinary and postprandial plasma metabolites in overweight and moderately obese human subjects. J Sci Food Agric 2018; 98:5598-5605. [PMID: 29696654 DOI: 10.1002/jsfa.9103] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 03/16/2018] [Accepted: 04/26/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Casein and whey proteins differ in amino acid composition and absorption rate; however, the absorption rate of casein can be increased to mimic that of whey proteins by exogenous hydrolysis. In view of these compositional differences, we studied the metabolic responses to intake of casein, hydrolyzed casein, and whey proteins in overweight and moderately obese men and women by investigating select urinary and blood plasma metabolites. RESULTS A total of 21 urinary and 23 plasma metabolites were identified by nuclear magnetic resonance spectroscopy. The postprandial plasma metabolites revealed a significant diet-time interaction for isoleucine (P = 0.001) and tyrosine (P = 0.001). The level of isoleucine and tyrosine peaked 90 min postprandially with a 1.4-fold difference following intake of whey proteins compared with either casein or hydrolyzed casein. A 1.2-fold higher urinary level of lactate was observed after intake of whey proteins compared with intake of intact casein (P < 0.01). CONCLUSION The plasma metabolites revealed different amino acid profiles reflecting the amino acid composition of casein and whey proteins. Furthermore, the results support that casein hydrolysates neither affect the postprandial amino acid absorption rate nor the amino acid level compared with that of intact casein. The urinary lactate increases following whey protein intake might indicate a higher metabolism of glucogenic amino acids. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Mette Schmedes
- Department of Food Science, Aarhus University, Aarslev, Denmark
| | - Line Q Bendtsen
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Sisse Gomes
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Bjørn Liaset
- Department of Seafood in Model Systems, Institute of Marine Research, Bergen, Norway
| | - Jens J Holst
- Department of Biomedical Sciences, The NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Christian Ritz
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Department of Biomedical Sciences, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark
| | - Anders Sjödin
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Arne Astrup
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jette F Young
- Department of Food Science, Aarhus University, Aarslev, Denmark
| | | | - Hanne C Bertram
- Department of Food Science, Aarhus University, Aarslev, Denmark
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15
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Hostrup M, Reitelseder S, Jessen S, Kalsen A, Nyberg M, Egelund J, Kreiberg M, Kristensen CM, Thomassen M, Pilegaard H, Backer V, Jacobson GA, Holm L, Bangsbo J. Beta 2 -adrenoceptor agonist salbutamol increases protein turnover rates and alters signalling in skeletal muscle after resistance exercise in young men. J Physiol 2018; 596:4121-4139. [PMID: 29968301 DOI: 10.1113/jp275560] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 06/29/2018] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS Animal models have shown that beta2 -adrenoceptor stimulation increases protein synthesis and attenuates breakdown processes in skeletal muscle. Thus, the beta2 -adrenoceptor is a potential target in the treatment of disuse-, disease- and age-related muscle atrophy. In the present study, we show that a few days of oral treatment with the commonly prescribed beta2 -adrenoceptor agonist, salbutamol, increased skeletal muscle protein synthesis and breakdown during the first 5 h after resistance exercise in young men. Salbutamol also counteracted a negative net protein balance in skeletal muscle after resistance exercise. Changes in protein turnover rates induced by salbutamol were associated with protein kinase A-signalling, activation of Akt2 and modulation of mRNA levels of growth-regulating proteins in skeletal muscle. These findings indicate that protein turnover rates can be augmented by beta2 -adrenoceptor agonist treatment during recovery from resistance exercise in humans. ABSTRACT The effect of beta2 -adrenoceptor stimulation on skeletal muscle protein turnover and intracellular signalling is insufficiently explored in humans, particularly in association with exercise. In a randomized, placebo-controlled, cross-over study investigating 12 trained men, the effects of beta2 -agonist (6 × 4 mg oral salbutamol) on protein turnover rates, intracellular signalling and mRNA response in skeletal muscle were investigated 0.5-5 h after quadriceps resistance exercise. Each trial was preceded by a 4-day lead-in treatment period. Leg protein turnover rates were assessed by infusion of [13 C6 ]-phenylalanine and sampling of arterial and venous blood, as well as vastus lateralis muscle biopsies 0.5 and 5 h after exercise. Furthermore, myofibrillar fractional synthesis rate, intracellular signalling and mRNA response were measured in muscle biopsies. The mean (95% confidence interval) myofibrillar fractional synthesis rate was higher for salbutamol than placebo [0.079 (95% CI, 0.064 to 0.093) vs. 0.066 (95% CI, 0.056 to 0.075%) × h-1 ] (P < 0.05). Mean net leg phenylalanine balance 0.5-5 h after exercise was higher for salbutamol than placebo [3.6 (95% CI, 1.0 to 6.2 nmol) × min-1 × 100 gLeg Lean Mass-1 ] (P < 0.01). Phosphorylation of Akt2, cAMP response element binding protein and PKA substrate 0.5 and 5 h after exercise, as well as phosphorylation of eEF2 5 h after exercise, was higher (P < 0.05) for salbutamol than placebo. Calpain-1, Forkhead box protein O1, myostatin and Smad3 mRNA content was higher (P < 0.01) for salbutamol than placebo 0.5 h after exercise, as well as Forkhead box protein O1 and myostatin mRNA content 5 h after exercise, whereas ActivinRIIB mRNA content was lower (P < 0.01) for salbutamol 5 h after exercise. These observations suggest that beta2 -agonist increases protein turnover rates in skeletal muscle after resistance exercise in humans, with concomitant cAMP/PKA and Akt2 signalling, as well as modulation of mRNA response of growth-regulating proteins.
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Affiliation(s)
- Morten Hostrup
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.,Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Søren Jessen
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.,Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Anders Kalsen
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.,Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Michael Nyberg
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jon Egelund
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kreiberg
- Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | | | - Martin Thomassen
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Henriette Pilegaard
- Department of Biology, University of Copenhagen, Copenhagen, Copenhagen, Denmark
| | - Vibeke Backer
- Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Glenn A Jacobson
- Division of Pharmacy, School of Medicine, University of Tasmania, Hobart, Australia
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg University 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, UK
| | - Jens Bangsbo
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Agergaard J, Bülow J, Jensen JK, Reitelseder S, Bornø A, Drummond MJ, Schjerling P, Holm L. Effect of light-load resistance exercise on postprandial amino acid transporter expression in elderly men. Physiol Rep 2017; 5:5/18/e13444. [PMID: 28963124 PMCID: PMC5617931 DOI: 10.14814/phy2.13444] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 08/04/2017] [Accepted: 08/10/2017] [Indexed: 02/07/2023] Open
Abstract
An impaired amino acid sensing is associated with age‐related loss of skeletal muscle mass. We tested whether light‐load resistance exercise (LL‐RE) affects postprandial amino acid transporter (AAT) expression in aging skeletal muscle. Untrained, healthy men (age: +65 years) were subjected to 13 h of supine rest. After 2 1/2 h of rest, unilateral LL‐RE was conducted (leg extensions, 10 sets of 36 repetitions) at 16% 1RM. Thereafter, the subjects were randomized into groups that orally ingested 40 g of whey protein either as hourly drinks (4 g per drink) (PULSE, N = 10) or two boluses (28 g at 0 h and 12 g at 7 h) (BOLUS, N = 10), or hourly isocaloric maltodextrin drinks (placebo, N = 10). Quadriceps muscle biopsies were taken at 0, 3, 7, and 10 h postexercise from both the resting and exercised leg, from which the membrane protein and mRNA expression of select AATs were analyzed by Western Blot and RT‐PCR, respectively. LAT1 and PAT1 protein expression increased in response to LL‐RE in the PULSE group, and SNAT2 and PAT1 protein expression increased in the BOLUS group when plasma BCAA concentration was low. In all three groups, LL‐RE increased LAT1 mRNA expression, whereas a time course decrease in SNAT2 mRNA expression was observed. LL‐RE increased membrane‐associated AAT protein expression and mRNA expression. Altered AAT protein expression was only seen in groups that ingested whey protein, with the greatest effect observed after hourly feeding. This points toward an importance of AATs in the anabolic response following LL‐RE and protein intake.
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Affiliation(s)
- Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark .,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 Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacob K Jensen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Andreas Bornø
- Clinical Metabolomics Core Facility, Rigshospitalet, Copenhagen, Denmark
| | - Micah J Drummond
- Department of Physical Therapy, University of Utah, Salt Lake City, Utah
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Ageing, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,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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17
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Dideriksen K, Boesen AP, Reitelseder S, Couppé C, Svensson R, Schjerling P, Magnusson SP, Holm L, Kjaer M. Tendon collagen synthesis declines with immobilization in elderly humans: no effect of anti-inflammatory medication. J Appl Physiol (1985) 2017; 122:273-282. [DOI: 10.1152/japplphysiol.00809.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/23/2016] [Accepted: 12/01/2016] [Indexed: 01/23/2023] Open
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) are used as pain killers during periods of unloading caused by traumatic occurrences or diseases. However, it is unknown how tendon protein turnover and mechanical properties respond to unloading and subsequent reloading in elderly humans, and whether NSAID treatment would affect the tendon adaptations during such periods. Thus we studied human patellar tendon protein synthesis and mechanical properties during immobilization and subsequent rehabilitating resistance training and the influence of NSAIDs upon these parameters. Nineteen men (range 60–80 yr) were randomly assigned to NSAIDs (ibuprofen 1,200 mg/day; Ibu) or placebo (Plc). One lower limb was immobilized in a cast for 2 wk and retrained for 6 wk. Tendon collagen protein synthesis, mechanical properties, size, expression of genes related to collagen turnover and remodeling, and signal intensity (from magnetic resonance imaging) were investigated. Tendon collagen synthesis decreased ( P < 0.001), whereas tendon mechanical properties and size were generally unchanged with immobilization, and NSAIDs did not influence this. Matrix metalloproteinase-2 mRNA tended to increase ( P < 0.1) after immobilization in both groups, whereas scleraxis mRNA decreased with inactivity in the Plc group only ( P < 0.05). In elderly human tendons, collagen protein synthesis decreased after 2 wk of immobilization, whereas tendon stiffness and modulus were only marginally reduced, and NSAIDs had no influence upon this. This indicates an importance of mechanical loading for maintenance of tendon collagen turnover. However, reduced collagen production induced by short-term unloading may only marginally affect tendon mechanical properties in elderly individuals.NEW & NOTEWORTHY In elderly humans, 2 wk of inactivity reduces tendon collagen protein synthesis, while tendon stiffness and modulus are only marginally reduced, and NSAID treatment does not affect this. This indicates that mechanical loading is important for maintenance of tendon collagen turnover and that changes in collagen turnover induced by short-term immobilization may only have minor impact on the internal structures that are essential for mechanical properties in elderly tendons.
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Affiliation(s)
- Kasper Dideriksen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Anders P. Boesen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
- Institute of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
| | - Christian Couppé
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
- Department of Physical Therapy, Musculoskeletal Rehabilitation Research Unit, Bispebjerg Hospital, Denmark
| | - Rene Svensson
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Peter Schjerling
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - S. Peter Magnusson
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
- Department of Physical Therapy, Musculoskeletal Rehabilitation Research Unit, Bispebjerg Hospital, Denmark
| | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
- Institute of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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Jensen T, Bechshoeft RL, Giacalone D, Otto MH, Castro-Mejía J, Bin Ahmad HF, Reitelseder S, Jespersen AP. Whey protein stories - An experiment in writing a multidisciplinary biography. Appetite 2016; 107:285-294. [PMID: 27521163 DOI: 10.1016/j.appet.2016.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 06/30/2016] [Accepted: 08/08/2016] [Indexed: 01/10/2023]
Abstract
This is an experimental, dual-purpose article about whey protein and how to conduct interdisciplinary analyses and writings. On the one hand, this article is a multidisciplinary commodity biography, which consists of five descriptions of whey protein written by the five different research groups involved in the interdisciplinary research project CALM(Counteracting Age-related loss of Skeletal Muscle Mass). On the other hand, it is a meta-analysis, which aims to uncover and highlight examples of how the five descriptions contribute to each other with insights into the contextualisation of knowledge, contrasts between the descriptions and the new dimensions they bring to established fields of interest. The meta-analysis also contains a discussion of interdisciplinary study objects and the usefulness of the multidisciplinary commodity biography as a format for interdisciplinary publications. The article contributes to the field of food studies with a multidisciplinary biography of whey protein - including its sensory qualities and challenges, insights into its cultural history, its nutritional value and effects on the human body and an analysis of how it is perceived by people who consume it. The biography thereby expands upon existing understandings of whey protein while discussing the usefulness of employing the commodity biography format in interdisciplinary writing. Moreover, the article contributes to the field of interdisciplinary research by providing a practical example of a joint publication and reflections upon the existence, interaction and possibilities of monodisciplinary knowledge structures within interdisciplinary studies and publications.
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Affiliation(s)
- Tenna Jensen
- Saxo Institute, Faculty of Humanities, University of Copenhagen, Denmark.
| | - Rasmus L Bechshoeft
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Denmark; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Davide Giacalone
- Department of Food Science, Faculty of Science, University of Copenhagen, Denmark; Department of Technology and Innovation, University of Southern Denmark, Denmark
| | - Marie Haulund Otto
- Saxo Institute, Faculty of Humanities, University of Copenhagen, Denmark
| | - Josue Castro-Mejía
- Department of Food Science, Faculty of Science, University of Copenhagen, Denmark
| | | | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Denmark; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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Bechshøft RL, Reitelseder S, Højfeldt G, Castro-Mejía JL, Khakimov B, Ahmad HFB, Kjær M, Engelsen SB, Johansen SMB, Rasmussen MA, Lassen AJ, Jensen T, Beyer N, Serena A, Perez-Cueto FJA, Nielsen DS, Jespersen AP, Holm L. Counteracting Age-related Loss of Skeletal Muscle Mass: a clinical and ethnological trial on the role of protein supplementation and training load (CALM Intervention Study): study protocol for a randomized controlled trial. Trials 2016; 17:397. [PMID: 27507236 PMCID: PMC4977774 DOI: 10.1186/s13063-016-1512-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 07/08/2016] [Indexed: 12/12/2022] Open
Abstract
Background Aging is associated with decreased muscle mass and functional capacity, which in turn decrease quality of life. The number of citizens over the age of 65 years in the Western world will increase by 50 % over the next four decades, and this demographic shift brings forth new challenges at both societal and individual levels. Only a few longitudinal studies have been reported, but whey protein supplementation seems to improve muscle mass and function, and its combination with heavy strength training appears even more effective. However, heavy resistance training may reduce adherence to training, thereby attenuating the overall benefits of training. We hypothesize that light load resistance training is more efficient when both adherence and physical improvement are considered longitudinally. We launched the interdisciplinary project on Counteracting Age-related Loss of Skeletal Muscle Mass (CALM) to investigate the impact of lifestyle changes on physical and functional outcomes as well as everyday practices and habits in a qualitative context. Methods We will randomize 205 participants older than 65 years to be given 1 year of two daily nutrient supplements with 10 g of sucrose and 20 g of either collagen protein, carbohydrates, or whey. Further, two groups will perform either heavy progressive resistance training or light load training on top of the whey supplement. Discussion The primary outcome of the CALM Intervention Study is the change in thigh cross-sectional area. Moreover, we will evaluate changes in physical performance, muscle fiber type and acute anabolic response to whey protein ingestion, sensory adaptation, gut microbiome, and a range of other measures, combined with questionnaires on life quality and qualitative interviews with selected subjects. The CALM Intervention Study will generate scientific evidence and recommendations to counteract age-related loss of skeletal muscle mass in elderly individuals. Trial registration ClinicalTrials.gov NCT02034760. Registered on 10 January 2014. ClinicalTrials.gov NCT02115698. Registered on 14 April 2014. Danish regional committee of the Capital Region H-4-2013-070. Registered on 4 July 2013. Danish Data Protection Agency 2012-58-0004 – BBH-2015-001 I-Suite 03432. Registered on 9 January 2015.
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Affiliation(s)
- Rasmus Leidesdorff Bechshøft
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark.,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Grith Højfeldt
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark
| | | | - Bekzod Khakimov
- Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Hajar Fauzan Bin Ahmad
- Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kjær
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark
| | - Søren Balling Engelsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | | | - Morten Arendt Rasmussen
- Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.,Copenhagen Prospective Studies on Asthma in Childhood, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Danish Pediatric Asthma Center, Gentofte Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Aske Juul Lassen
- SAXO Institute, Faculty of Humanities, University of Copenhagen, Copenhagen, Denmark
| | - Tenna Jensen
- SAXO Institute, Faculty of Humanities, University of Copenhagen, Copenhagen, Denmark
| | - Nina Beyer
- Musculoskeletal Rehabilitation Research Unit, Department of Physical and Occupational Therapy, Bispebjerg Hospital, Copenhagen, Denmark
| | - Anja Serena
- Arla Foods Ingredients Group P/S, Viby J, Denmark
| | | | - Dennis Sandris Nielsen
- Department of Food Science, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | | | - Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400, Copenhagen, NV, Denmark. .,Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Dideriksen K, Reitelseder S, Malmgaard-Clausen NM, Bechshoeft R, Petersen RK, Mikkelsen UR, Holm L. No effect of anti-inflammatory medication on postprandial and postexercise muscle protein synthesis in elderly men with slightly elevated systemic inflammation. Exp Gerontol 2016; 83:120-9. [PMID: 27497779 DOI: 10.1016/j.exger.2016.07.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 06/27/2016] [Accepted: 07/29/2016] [Indexed: 01/31/2023]
Abstract
BACKGROUND Based on circulating C-reactive protein (CRP) levels, some individuals develop slightly increased inflammation as they age. In elderly inflamed rats, the muscle response to protein feeding is impaired, whereas it can be maintained by treatment with non-steroidal anti-inflammatory drugs (NSAIDs). It is unknown whether this applies to elderly humans with increased inflammation. Thus, the muscle response to whey protein bolus ingestion with and without acute resistance exercise was compared between healthy elderly individuals and elderly individuals with slightly increased inflammation±NSAID treatment. METHODS Twenty-four elderly men (>60years) were recruited. Of those, 14 displayed a slightly increased systemic inflammation (CRP>2mg/l) and were randomly assigned to NSAID (Ibuprofen 1800mg/day) or placebo treatment for 1week. The remaining 10 elderly individuals served as healthy controls (CRP<1mg/l). The muscle protein synthetic response was measured as the fractional synthetic rate (FSR) and p70S6K phosphorylation-to-total protein ratio. RESULTS The basal myofibrillar FSR and the myofibrillar FSR responses to whey protein bolus ingestion with and without acute resistance exercise were maintained in inflamed elderly compared to healthy controls (p>0.05) and so was p70S6K phosphorylation. Moreover, NSAID treatment did not significantly improve the myofibrillar and connective tissue FSR responses or reduce the plasma CRP level in inflamed, elderly individuals (p>0.05). CONCLUSION A slight increase in systemic inflammation does not affect the basal myofibrillar FSR or the myofibrillar FSR responses, which suggests that elderly individuals with slightly increased inflammation can benefit from protein ingestion and resistance exercise to stimulate muscle protein anabolism. Moreover, the NSAID treatment did not significantly affect the myofibrillar or connective tissue FSR responses to protein ingestion and acute resistance exercise.
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Affiliation(s)
- K Dideriksen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - S Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Institute of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - N M Malmgaard-Clausen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - R Bechshoeft
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Institute of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - R K Petersen
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - U R Mikkelsen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - L Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Institute of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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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] [What about the content of this article? (0)] [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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Bojsen-Møller KN, Jacobsen SH, Dirksen C, Jørgensen NB, Reitelseder S, Jensen JEB, Kristiansen VB, Holst JJ, van Hall G, Madsbad S. Accelerated protein digestion and amino acid absorption after Roux-en-Y gastric bypass. Am J Clin Nutr 2015; 102:600-7. [PMID: 26245808 DOI: 10.3945/ajcn.115.109298] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 07/02/2015] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Roux-en-Y gastric bypass (RYGB) involves exclusion of major parts of the stomach and changes in admixture of gastro-pancreatic enzymes, which could have a major impact on protein digestion and amino acid absorption. OBJECTIVE We investigated the effect of RYGB on amino acid appearance in the systemic circulation from orally ingested protein and from endogenous release. DESIGN Nine obese glucose-tolerant subjects, with a mean body mass index (in kg/m(2)) of 39.2 (95% CI: 35.2, 43.3) and mean glycated hemoglobin of 5.3% (95% CI: 4.9%, 5.6%), were studied before and 3 mo after RYGB. Leucine and phenylalanine kinetics were determined under basal conditions and during 4 postprandial hours by intravenous infusions of [3,3,3-(2)H3]-leucine and [ring-(2)D5]-phenylalanine combined with ingestion of [1-(13)C]-leucine intrinsically labeled caseinate as the sole protein source of the meal. Changes in body composition were assessed by dual-energy X-ray absorptiometry. RESULTS After RYGB, basal plasma leucine concentration did not change, but marked changes were seen postprandially with 1.7-fold increased peak concentrations (before—mean: 217 μmol/L; 95% CI: 191, 243 μmol/L; 3 mo—mean: 377 μmol/L; 95% CI: 252, 502 μmol/L; P = 0.012) and 2-fold increased incremental AUC (before-mean: 4.1 mmol ∙ min/L; 95% CI: 2.7, 5.5 mmol ∙ min/L; 3 mo-mean: 9.5 mmol ∙ min/L; 95% CI: 4.9, 14.2 mmol ∙ min/L; P = 0.032). However, the postprandial hyperleucinemia was transient, and concentrations were below basal concentrations in the fourth postprandial hour. These concentration differences were mainly caused by changes in leucine appearance rate from orally ingested caseinate: peak rate increased nearly 3-fold [before—mean: 0.5 μmol/(kg fat-free mass ∙ min); 95% CI: 0.4, 0.5 μmol/(kg fat-free mass ∙ min); 3 mo—mean 1.4 μmol/(kg fat-free mass ∙ min); 95% CI: 0.8, 1.9 μmol/(kg fat-free mass ∙ min); P = 0.002], and time to peak was much shorter (before—mean: 173 min; 95% CI: 137, 209 min; 3 mo—mean: 65 min; 95% CI: 46, 84 min; P < 0.001). Only minor changes were seen in endogenous leucine release after RYGB. CONCLUSIONS RYGB accelerates caseinate digestion and amino acid absorption, resulting in faster and higher but more transient postprandial elevation of plasma amino acids. Changes are likely mediated by accelerated intestinal nutrient entry and clearly demonstrate that protein digestion is not impaired after RYGB. This trial was registered at clinicaltrials.gov as NCT01559792.
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Affiliation(s)
| | - Siv H Jacobsen
- Department of Endocrinology and Novo Nordisk Foundation Centre for Basic Metabolic Research and
| | - Carsten Dirksen
- Department of Endocrinology and Novo Nordisk Foundation Centre for Basic Metabolic Research and
| | - Nils B Jørgensen
- Department of Endocrinology and Novo Nordisk Foundation Centre for Basic Metabolic Research and
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark
| | | | - Viggo B Kristiansen
- Department of Surgical Gastroenterology, Hvidovre Hospital, Copenhagen, Denmark
| | - Jens J Holst
- Novo Nordisk Foundation Centre for Basic Metabolic Research and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Clinical Metabolomics, Rigshospitalet, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology and Novo Nordisk Foundation Centre for Basic Metabolic Research and
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Holm L, Jespersen AP, Nielsen DS, Frøst MB, Reitelseder S, Jensen T, Engelsen SB, Kjaer M, Damsholt T. Hurrah for the increasing longevity: feasible strategies to counteract age-related loss of skeletal muscle mass. Scand J Med Sci Sports 2015; 25:1-2. [DOI: 10.1111/sms.12415] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- L. Holm
- Institute of Sports Medicine and Department of Orthopedic Surgery; Bispebjerg Hospital; Copenhagen Denmark
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - A. P. Jespersen
- The SAXO Institute; Ethnology Section; Faculty of Humanities; University of Copenhagen; Denmark
| | - D. S. Nielsen
- Department of Food Science; Faculty of Science; University of Copenhagen; Denmark
| | - M. B. Frøst
- Department of Food Science; Faculty of Science; University of Copenhagen; Denmark
| | - S. Reitelseder
- Institute of Sports Medicine and Department of Orthopedic Surgery; Bispebjerg Hospital; Copenhagen Denmark
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Denmark
| | - T. Jensen
- The SAXO Institute; Ethnology Section; Faculty of Humanities; University of Copenhagen; Denmark
| | - S. B. Engelsen
- Department of Food Science; Faculty of Science; University of Copenhagen; Denmark
| | - M. Kjaer
- Institute of Sports Medicine and Department of Orthopedic Surgery; Bispebjerg Hospital; Copenhagen Denmark
| | - T. Damsholt
- The SAXO Institute; Ethnology Section; Faculty of Humanities; University of Copenhagen; Denmark
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Holm L, Reitelseder S, Dideriksen K, Nielsen RH, Bülow J, Kjaer M. The single-biopsy approach in determining protein synthesis in human slow-turning-over tissue: use of flood-primed, continuous infusion of amino acid tracers. Am J Physiol Endocrinol Metab 2014; 306:E1330-9. [PMID: 24760987 DOI: 10.1152/ajpendo.00084.2014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Muscle protein synthesis (MPS) rate is determined conventionally by obtaining two or more tissue biopsies during a primed, continuous infusion of a stable isotopically labeled amino acid. The purpose of the present study was to test whether tracer priming given as a flooding dose, thereby securing an instantaneous labeling of the tissue pools of free tracee amino acids, followed by a continuous infusion of the same tracer to maintain tracer isotopic steady state, could be used to determine the MPS rate over a prolonged period of time by obtaining only a single tissue biopsy. We showed that the tracer from the flood prime appeared immediately in the muscle free pool of amino acids and that this abundance could be kept constant by a subsequent continuous infusion of the tracer. When using phenylalanine as tracer, the flood-primed, continuous infusion protocol does not stimulate the MPS rate per se. In conclusion, the flood-primed, continuous infusion protocol using phenylalanine as tracer can validly be used to measure the protein synthesis rate in human in vivo experiments by obtaining only a single tissue biopsy after a prolonged infusion period.
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Affiliation(s)
- Lars Holm
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Kasper Dideriksen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
| | - Rie H Nielsen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
| | - Jacob Bülow
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark; and
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Reitelseder S, Bülow J, Agergaard J, Kjaer M, Holm L. Daily living physical activities and muscle protein synthesis: a new and applied method with intrinsically stable isotope‐labeled milk proteins as tracer (702.8). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.702.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Søren Reitelseder
- Center for Healthy AgingCopenhagenDenmark
- Department of Orthopedic Surgery MBispebjerg Hospital Institute of Sports MedicineCopenhagenCopenhagenNVDenmark
| | - Jacob Bülow
- Center for Healthy AgingCopenhagenDenmark
- Department of Orthopedic Surgery MBispebjerg Hospital Institute of Sports MedicineCopenhagenCopenhagenNVDenmark
| | - Jakob Agergaard
- Center for Healthy AgingCopenhagenDenmark
- Department of Orthopedic Surgery MBispebjerg Hospital Institute of Sports MedicineCopenhagenCopenhagenNVDenmark
| | - Michael Kjaer
- Center for Healthy AgingCopenhagenDenmark
- Department of Orthopedic Surgery MBispebjerg Hospital Institute of Sports MedicineCopenhagenCopenhagenNVDenmark
| | - Lars Holm
- Center for Healthy AgingCopenhagenDenmark
- Institute of Biomedical ScienceCopenhagenDenmark
- Department of Orthopedic Surgery MBispebjerg Hospital Institute of Sports MedicineCopenhagenCopenhagenNVDenmark
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Agergaard J, Bülow J, Kildevang Jensen J, Reitelseder S, Schjerling P, Drummond MJ, Kjær M, Holm L. The effect of light load resistance exercise and whey protein supplementation on muscle protein synthesis and amino‐acid transporters in elderly (702.7). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.702.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jakob Agergaard
- Department of Physical TherapyUniversity of UtahSalt Lake CityUTUnited States
- Insitute of Sports Medicine CopenhagenCopenhagenNVDenmark
| | - Jacob Bülow
- Insitute of Sports Medicine CopenhagenCopenhagenNVDenmark
| | | | | | | | - Micah J. Drummond
- Department of Physical TherapyUniversity of UtahSalt Lake CityUTUnited States
| | - Michael Kjær
- Insitute of Sports Medicine CopenhagenCopenhagenNVDenmark
| | - Lars Holm
- Insitute of Sports Medicine CopenhagenCopenhagenNVDenmark
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Nielsen RH, Holm L, Malmgaard-Clausen NM, Reitelseder S, Heinemeier KM, Kjaer M. Increase in tendon protein synthesis in response to insulin-like growth factor-I is preserved in elderly men. J Appl Physiol (1985) 2014; 116:42-6. [DOI: 10.1152/japplphysiol.01084.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Insulin-like growth factor-I (IGF-I) is known to be an anabolic factor in tendon, and the systemic levels are reduced with aging. However, it is uncertain how tendon fibroblasts are involved in tendon aging and how aging cells respond to IGF-I. The purpose of this study was to investigate the in vivo IGF-I stimulation of tendon protein synthesis in elderly compared with young men. We injected IGF-I in the patellar tendons of young ( n = 11, 20–30 yr of age) and old ( n = 11, 66–75 yr of age) men, and the acute fractional synthesis rate (FSR) of tendon protein was measured with the stable isotope technique and compared with the contralateral side (injected with saline as control). We found that tendons injected with IGF-I had significantly higher protein FSR compared with controls (old group: 0.018 ± 0.015 vs. 0.008 ± 0.008, young group: 0.016 ± 0.009 vs. 0.009 ± 0.006%/h, mean ± SE, P < 0.01). This increase in protein synthesis was seen in both young and old men, with no differences between age groups. The old group had markedly lower serum IGF-I levels compared with young (165 ± 17 vs. 281 ± 27 ng/ml, P < 0.01). In conclusion, local IGF-I stimulated tendon protein synthesis in both young and old men, despite lower systemic IGF-I levels in the old group. This could indicate that the changed phenotype in aging tendon is not caused by decreased fibroblast function.
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Affiliation(s)
- Rie Harboe Nielsen
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Lars Holm
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Nikolaj Mølkjær Malmgaard-Clausen
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Søren Reitelseder
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Katja Maria Heinemeier
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Michael Kjaer
- Department of Orthopedic Surgery, Institute of Sports Medicine, Bispebjerg Hospital and Faculty of Health and Medical Sciences, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
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Reitelseder S, Agergaard J, Doessing S, Helmark IC, Schjerling P, van Hall G, Kjaer M, Holm L. Positive muscle protein net balance and differential regulation of atrogene expression after resistance exercise and milk protein supplementation. Eur J Nutr 2013; 53:321-33. [DOI: 10.1007/s00394-013-0530-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 04/21/2013] [Indexed: 11/24/2022]
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30
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Reitelseder S, Dideriksen K, Nielsen RH, Kjaer M, Holm L. Flood‐primed continuous tracer infusion complies with the precursor‐labeling assumptions for measuring the muscle fractional synthesis rate using a single biopsy approach. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.631.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Søren Reitelseder
- Department of Orthopedic Surgery MBispebjerg HospitalInstitute of Sports Medicine CopenhagenCopenhagen NVDenmark
| | - Kasper Dideriksen
- Department of Orthopedic Surgery MBispebjerg HospitalInstitute of Sports Medicine CopenhagenCopenhagen NVDenmark
| | - Rie Harboe Nielsen
- Department of Orthopedic Surgery MBispebjerg HospitalInstitute of Sports Medicine CopenhagenCopenhagen NVDenmark
| | - Michael Kjaer
- Department of Orthopedic Surgery MBispebjerg HospitalInstitute of Sports Medicine CopenhagenCopenhagen NVDenmark
| | - Lars Holm
- Department of Orthopedic Surgery MBispebjerg HospitalInstitute of Sports Medicine CopenhagenCopenhagen NVDenmark
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Holm L, Reitelseder S, Dideriksen K, Nielsen RH, Doessing S, Kjaer M. Human myofibrillar fractional breakdown rate determined by the disappearance rate of water‐derived
2
H alanine. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.350.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lars Holm
- Institute of Sports MedicineBispebjerg HospitalCopenhagen NVDenmark
| | | | | | - Rie H Nielsen
- Institute of Sports MedicineBispebjerg HospitalCopenhagen NVDenmark
| | - Simon Doessing
- Institute of Sports MedicineBispebjerg HospitalCopenhagen NVDenmark
| | - Michael Kjaer
- Institute of Sports MedicineBispebjerg HospitalCopenhagen NVDenmark
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Agergaard J, Reitelseder S, Pedersen TG, Doessing S, Schjerling P, Langberg H, Miller BF, Aagaard P, Kjaer M, Holm L. Myogenic, matrix, and growth factor mRNA expression in human skeletal muscle: effect of contraction intensity and feeding. Muscle Nerve 2013; 47:748-59. [PMID: 23519763 DOI: 10.1002/mus.23667] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2012] [Indexed: 11/08/2022]
Abstract
INTRODUCTION We examined short-term (3-hour) and long-term (12-week) training effects after heavy load [HL; 70% 1RM] and light load (LL; 16% 1RM) exercise. METHODS mRNA expression of genes involved in skeletal muscle remodeling were analyzed and muscle activity (EMG measurements) was measured. RESULTS Relative muscle activity differed between HL and LL resistance exercise, whereas median power frequency was even, suggesting an equal muscle-fiber-type recruitment distribution. mRNA expression of Myf6, myogenin, and p21 was mostly increased, and myostatin was mostly depressed by HL resistance exercise. No major differences were seen in atrophy-related genes between HL and LL resistance exercise. No changes were seen over 12-week training for any of the targets. CONCLUSIONS Resistance exercise at LL and HL elevated the expression of genes involved in skeletal muscle hypertrophy, although the greatest response was from HL. However, no long-term effect from either LL or HL resistance exercise was seen on basal levels of the mRNA targets.
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Affiliation(s)
- Jakob Agergaard
- Institute of Sports Medicine, Department of Orthopedic Surgery M, Bispebjerg Hospital, Denmark.
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Dideriksen K, Reitelseder S, Holm L. Influence of amino acids, dietary protein, and physical activity on muscle mass development in humans. Nutrients 2013; 5:852-76. [PMID: 23486194 PMCID: PMC3705323 DOI: 10.3390/nu5030852] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 02/13/2013] [Accepted: 02/25/2013] [Indexed: 12/14/2022] Open
Abstract
Ingestion of protein is crucial for maintenance of a variety of body functions and within the scope of this review we will specifically focus on the regulation of skeletal muscle mass. A quantitative limitation exists as to how much muscle protein the body can synthesize in response to protein intake. Ingestion of excess protein exerts an unwanted load to the body and therefore, it is important to find the least amount of protein that provides the maximal hypertrophic stimulus. Hence, research has focused on revealing the relationship between protein intake (dose) and its resulting stimulation of muscle protein synthesis (response). In addition to the protein amount, the protein digestibility and, hence, the availability of its constituent amino acids is decisive for the response. In this regard, recent studies have provided in-depth knowledge about the time-course of the muscle protein synthetic response dependent on the characteristics of the protein ingested. The effect of protein intake on muscle protein accretion can further be stimulated by prior exercise training. In the ageing population, physical training may counteract the development of “anabolic resistance” and restore the beneficial effect of protein feeding. Presently, our knowledge is based on measures obtained in standardized experimental settings or during long-term intervention periods. However, to improve coherence between these types of data and to further improve our knowledge of the effects of protein ingestion, other investigative approaches than those presently used are requested.
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Affiliation(s)
- Kasper Dideriksen
- Institute of Sports Medicine, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark; E-Mails: (S.R.); (L.H.)
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +45-3531-3948; Fax: +45-3531-2733
| | - Søren Reitelseder
- Institute of Sports Medicine, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark; E-Mails: (S.R.); (L.H.)
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Lars Holm
- Institute of Sports Medicine, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark; E-Mails: (S.R.); (L.H.)
- Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
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Yde CC, Ditlev DB, Reitelseder S, Bertram HC. Metabonomic Response to Milk Proteins after a Single Bout of Heavy Resistance Exercise Elucidated by 1H Nuclear Magnetic Resonance Spectroscopy. Metabolites 2013; 3:33-46. [PMID: 24957889 PMCID: PMC3901252 DOI: 10.3390/metabo3010033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 12/18/2012] [Accepted: 01/21/2013] [Indexed: 11/30/2022] Open
Abstract
In the present study, proton NMR-based metabonomics was applied on femoral arterial plasma samples collected from young male subjects (milk protein n = 12 in a crossover design; non-caloric control n = 8) at different time intervals (70, 220, 370 min) after heavy resistance training and intake of either a whey or calcium caseinate protein drink in order to elucidate the impact of the protein source on post-exercise metabolism, which is important for muscle hypertrophy. Dynamic changes in the post-exercise plasma metabolite profile consisted of fluctuations in alanine, beta-hydroxybutyrate, branched amino acids, creatine, glucose, glutamine, glutamate, histidine, lipids and tyrosine. In comparison with the intake of a non-caloric drink, the same pattern of changes in low-molecular weight plasma metabolites was found for both whey and caseinate intake. However, the study indicated that whey and caseinate protein intake had a different impact on low-density and very-low-density lipoproteins present in the blood, which may be ascribed to different effects of the two protein sources on the mobilization of lipid resources during energy deficiency. In conclusion, no difference in the effects on low-molecular weight metabolites as measured by proton NMR-based metabonomics was found between the two protein sources.
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Affiliation(s)
| | | | - Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Denmark.
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Bechshoeft R, Dideriksen KJ, Reitelseder S, Scheike T, Kjaer M, Holm L. The anabolic potential of dietary protein intake on skeletal muscle is prolonged by prior light-load exercise. Clin Nutr 2012; 32:236-44. [PMID: 22867749 DOI: 10.1016/j.clnu.2012.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 06/01/2012] [Accepted: 06/23/2012] [Indexed: 11/18/2022]
Abstract
BACKGROUND & AIMS Hyperaminoacidemia stimulates myofibrillar fractional synthesis rate (myoFSR) transiently in resting skeletal muscle. We investigated whether light-load resistance exercise can extent this responsiveness. METHODS Ten healthy males exercised one leg with a light-load resistance-like exercise at 16% of 1 repetition maximum and received oral protein boluses every hour for a 10-h period. Their myoFSR was determined by [1-(13)C]-leucine incorporation. Muscle biopsies were obtained from the resting (REST) and exercised (EXC) muscles every 2.5-h in the protein-fed period. RESULTS Protein feeding significantly elevated plasma leucine and essential amino acids by an average of 39 ± 9% (mean ± SEM) and 20 ± 4%, respectively, compared to the basal concentrations: 197 ± 12 μmol L(-1) and 854 ± 35 μmol L(-1), respectively. The myoFSR was similar in EXC and REST muscles in the first 8 h (all time intervals p > 0.05). After 8 h the myoFSR dropped in the REST muscle to 0.041 ± 0.005%·h(-1), which was 65 ± 5% of the rate in EXC leg at the same time point (0.062 ± 0.004%·h(-1)) and 80 ± 14% of the level in REST leg from 0.5 to 8 h (0.056 ± 0.005%·h(-1)) (interaction p < 0.05). CONCLUSIONS Compared to rest, light-load exercise prolonged the stimulatory effect of dietary protein on muscle biosynthesis providing perspectives for a muscle restorative effect in clinical settings where strenuous activity is intolerable.
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Affiliation(s)
- Rasmus Bechshoeft
- Institute of Sports Medicine, Dept. of Orthopedic Surgery M81, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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Hansen M, Skovgaard D, Reitelseder S, Holm L, Langbjerg H, Kjaer M. Effects of Estrogen Replacement and Lower Androgen Status on Skeletal Muscle Collagen and Myofibrillar Protein Synthesis in Postmenopausal Women. J Gerontol A Biol Sci Med Sci 2012; 67:1005-13. [DOI: 10.1093/gerona/gls007] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Nielsen RH, Doessing S, Goto K, Holm L, Reitelseder S, Agergaard J, Schjerling P, Flyvberg A, Kjaer M. GH receptor blocker administration and muscle-tendon collagen synthesis in humans. Growth Horm IGF Res 2011; 21:140-145. [PMID: 21498100 DOI: 10.1016/j.ghir.2011.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 03/24/2011] [Accepted: 03/24/2011] [Indexed: 01/18/2023]
Abstract
CONTEXT The growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis stimulates collagen synthesis in tendon and skeletal muscle, but no studies have investigated the effect of reducing IGF-I on collagen synthesis in healthy humans. OBJECTIVE We hypothesised, that a GH blockade would decrease IGF-I and collagen synthesis in the connective tissue of skeletal muscle and tendon. DESIGN The study was randomised and double blinded. PARTICIPANTS 20 healthy young males completed the study. INTERVENTION The participants were randomised to 2 weeks of GH receptor blocker supplementation (pegvisomant, 5 mg/day, n=9) or placebo (n=11). MAIN OUTCOME MEASURES Serum levels of GH, IGF-I and IGF-binding protein 3 (IGFBP-3) were measured before and after pegvisomant/placebo supplementation. Fractional synthesis rates (FSR) for collagen and myofibrillar protein were determined with stable isotopes in tendon and muscle, and mRNA for collagen (COL1A1 and COL3A1) as well as IGF-I isoforms (Ea and Ec) were measured in skeletal muscle. RESULTS Pegvisomant decreased serum IGF-I by 20% (p<0.01) and serum IGFBP-3 by 10% (p<0.05). Pegvisomant supplementation had no effect on collagen synthesis in tendon and skeletal muscle, nor was muscle myofibrillar protein synthesis affected. Similarly, pegvisomant supplementation had no effect on mRNA expression of IGF-I and collagen in skeletal muscle. CONCLUSION GH receptor blocker administration in healthy humans resulted in a moderate decrease in serum IGF-I. Collagen synthesis in tendon and skeletal muscle, as well as skeletal muscle IGF-I and collagen mRNA expression, was unaffected by GH receptor blocker supplementation.
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Affiliation(s)
- Rie Harboe Nielsen
- Institute of Sports Medicine, Dept. of Orthopaedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Denmark.
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Dideriksen KJ, Reitelseder S, Petersen SG, Hjort M, Helmark IC, Kjaer M, Holm L. Stimulation of muscle protein synthesis by whey and caseinate ingestion after resistance exercise in elderly individuals. Scand J Med Sci Sports 2011; 21:e372-83. [DOI: 10.1111/j.1600-0838.2011.01318.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Jespersen JG, Nedergaard A, Reitelseder S, Mikkelsen UR, Dideriksen KJ, Agergaard J, Kreiner F, Pott FC, Schjerling P, Kjaer M. Activated protein synthesis and suppressed protein breakdown signaling in skeletal muscle of critically ill patients. PLoS One 2011; 6:e18090. [PMID: 21483870 PMCID: PMC3069050 DOI: 10.1371/journal.pone.0018090] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 02/20/2011] [Indexed: 12/25/2022] Open
Abstract
Background Skeletal muscle mass is controlled by myostatin and Akt-dependent signaling on mammalian target of rapamycin (mTOR), glycogen synthase kinase 3β (GSK3β) and forkhead box O (FoxO) pathways, but it is unknown how these pathways are regulated in critically ill human muscle. To describe factors involved in muscle mass regulation, we investigated the phosphorylation and expression of key factors in these protein synthesis and breakdown signaling pathways in thigh skeletal muscle of critically ill intensive care unit (ICU) patients compared with healthy controls. Methodology/Principal Findings ICU patients were systemically inflamed, moderately hyperglycemic, received insulin therapy, and showed a tendency to lower plasma branched chain amino acids compared with controls. Using Western blotting we measured Akt, GSK3β, mTOR, ribosomal protein S6 kinase (S6k), eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), and muscle ring finger protein 1 (MuRF1); and by RT-PCR we determined mRNA expression of, among others, insulin-like growth factor 1 (IGF-1), FoxO 1, 3 and 4, atrogin1, MuRF1, interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and myostatin. Unexpectedly, in critically ill ICU patients Akt-mTOR-S6k signaling was substantially higher compared with controls. FoxO1 mRNA was higher in patients, whereas FoxO3, atrogin1 and myostatin mRNAs and MuRF1 protein were lower compared with controls. A moderate correlation (r2 = 0.36, p<0.05) between insulin infusion dose and phosphorylated Akt was demonstrated. Conclusions/Significance We present for the first time muscle protein turnover signaling in critically ill ICU patients, and we show signaling pathway activity towards a stimulation of muscle protein synthesis and a somewhat inhibited proteolysis.
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Affiliation(s)
- Jakob G Jespersen
- Department of Orthopedic Surgery M, Institute of Sports Medicine Copenhagen, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
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Reitelseder S, Agergaard J, Doessing S, Helmark IC, Lund P, Kristensen NB, Frystyk J, Flyvbjerg A, Schjerling P, van Hall G, Kjaer M, Holm L. Whey and casein labeled with L-[1-13C]leucine and muscle protein synthesis: effect of resistance exercise and protein ingestion. Am J Physiol Endocrinol Metab 2011; 300:E231-42. [PMID: 21045172 DOI: 10.1152/ajpendo.00513.2010] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Muscle protein turnover following resistance exercise and amino acid availability are relatively well described. By contrast, the beneficial effects of different sources of intact proteins in relation to exercise need further investigation. Our objective was to compare muscle anabolic responses to a single bolus intake of whey or casein after performance of heavy resistance exercise. Young male individuals were randomly assigned to participate in two protein trials (n = 9) or one control trial (n = 8). Infusion of l-[1-(13)C]leucine was carried out, and either whey, casein (0.3 g/kg lean body mass), or a noncaloric control drink was ingested immediately after exercise. l-[1-(13)C]leucine-labeled whey and casein were used while muscle protein synthesis (MPS) was assessed. Blood and muscle tissue samples were collected to measure systemic hormone and amino acid concentrations, tracer enrichments, and myofibrillar protein synthesis. Western blots were used to investigate the Akt signaling pathway. Plasma insulin and branched-chain amino acid concentrations increased to a greater extent after ingestion of whey compared with casein. Myofibrillar protein synthesis was equally increased 1-6 h postexercise after whey and casein intake, both of which were higher compared with control (P < 0.05). Phosphorylation of Akt and p70(S6K) was increased after exercise and protein intake (P < 0.05), but no differences were observed between the types of protein except for total 4E-BP1, which was higher after whey intake than after casein intake (P < 0.05). In conclusion, whey and casein intake immediately after resistance exercise results in an overall equal MPS response despite temporal differences in insulin and amino acid concentrations and 4E-BP1.
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Affiliation(s)
- Søren Reitelseder
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital and Center for Healthy Aging, University of Copenhagen, Copenhagen NV, Denmark.
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Mackey AL, Holm L, Reitelseder S, Pedersen TG, Doessing S, Kadi F, Kjaer M. Myogenic response of human skeletal muscle to 12 weeks of resistance training at light loading intensity. Scand J Med Sci Sports 2010; 21:773-82. [DOI: 10.1111/j.1600-0838.2010.01178.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Mikkelsen UR, Schjerling P, Helmark IC, Reitelseder S, Holm L, Skovgaard D, Langberg H, Kjaer M, Heinemeier KM. Local NSAID infusion does not affect protein synthesis and gene expression in human muscle after eccentric exercise. Scand J Med Sci Sports 2010; 21:630-44. [DOI: 10.1111/j.1600-0838.2010.01170.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Doessing S, Heinemeier KM, Holm L, Mackey AL, Schjerling P, Rennie M, Smith K, Reitelseder S, Kappelgaard AM, Rasmussen MH, Flyvbjerg A, Kjaer M. Growth hormone stimulates the collagen synthesis in human tendon and skeletal muscle without affecting myofibrillar protein synthesis. J Physiol 2009; 588:341-51. [PMID: 19933753 DOI: 10.1113/jphysiol.2009.179325] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
In skeletal muscle and tendon the extracellular matrix confers important tensile properties and is crucially important for tissue regeneration after injury. Musculoskeletal tissue adaptation is influenced by mechanical loading, which modulates the availability of growth factors, including growth hormone (GH) and insulin-like growth factor-I (IGF-I), which may be of key importance. To test the hypothesis that GH promotes matrix collagen synthesis in musculotendinous tissue, we investigated the effects of 14 day administration of 33-50 microg kg(-1) day(-1) recombinant human GH (rhGH) in healthy young individuals. rhGH administration caused an increase in serum GH, serum IGF-I, and IGF-I mRNA expression in tendon and muscle. Tendon collagen I mRNA expression and tendon collagen protein synthesis increased by 3.9-fold and 1.3-fold, respectively (P < 0.01 and P = 0.02), and muscle collagen I mRNA expression and muscle collagen protein synthesis increased by 2.3-fold and 5.8-fold, respectively (P < 0.01 and P = 0.06). Myofibrillar protein synthesis was unaffected by elevation of GH and IGF-I. Moderate exercise did not enhance the effects of GH manipulation. Thus, increased GH availability stimulates matrix collagen synthesis in skeletal muscle and tendon, but without any effect upon myofibrillar protein synthesis. The results suggest that GH is more important in strengthening the matrix tissue than for muscle cell hypertrophy in adult human musculotendinous tissue.
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Affiliation(s)
- Simon Doessing
- Institute of Sports Medicine, Bispebjerg Hospital, Center of Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen NV, Denmark.
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Holm L, Reitelseder S, Pedersen TG, Doessing S, Petersen SG, Flyvbjerg A, Andersen JL, Aagaard P, Kjaer M. Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity. J Appl Physiol (1985) 2008; 105:1454-61. [PMID: 18787090 DOI: 10.1152/japplphysiol.90538.2008] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same individual trained one leg at 70% of one-repetition maximum (1RM) (heavy load, HL) while training the other leg at 15.5% 1RM (light load, LL). Eleven sedentary men (age 25 +/- 1 yr) trained for 12 wk at three times/week. Before and after the intervention muscle hypertrophy was determined by magnetic resonance imaging, muscle biopsies were obtained bilaterally from vastus lateralis for determination of myosin heavy chain (MHC) composition, and maximal muscle strength was assessed by 1RM testing and in an isokinetic dynamometer at 60 degrees /s. Quadriceps muscle cross-sectional area increased (P < 0.05) 8 +/- 1% and 3 +/- 1% in HL and LL legs, respectively, with a greater gain in HL than LL (P < 0.05). Likewise, 1RM strength increased (P < 0.001) in both legs (HL: 36 +/- 5%, LL: 19 +/- 2%), albeit more so with HL (P < 0.01). Isokinetic 60 degrees /s muscle strength improved by 13 +/- 5% (P < 0.05) in HL but remained unchanged in LL (4 +/- 5%, not significant). Finally, MHC IIX protein expression was decreased with HL but not LL, despite identical total workload in HL and LL. Our main finding was that LL resistance training was sufficient to induce a small but significant muscle hypertrophy in healthy young men. However, LL resistance training was inferior to HL training in evoking adaptive changes in muscle size and contractile strength and was insufficient to induce changes in MHC composition.
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Affiliation(s)
- L Holm
- Institute of Sports Medicine, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark.
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Mackey AL, Holm L, Reitelseder S, Pedersen TG, Kadi F, Døssing S, Kjaer M. Increased myogenic precursor cell number in human skeletal muscle with 12 weeks of training at low intensity. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.753.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Abigail Louise Mackey
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Lars Holm
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Søren Reitelseder
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Troels Gravers Pedersen
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Fawzi Kadi
- School of Health and Medical SciencesÖrebro UniversityÖrebroSweden
| | - Simon Døssing
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Michael Kjaer
- Institute of Sports Medicine CopenhagenBispebjerg Hospital and Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark
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Kongsgaard M, Reitelseder S, Pedersen TG, Holm L, Aagaard P, Kjaer M, Magnusson SP. Region specific patellar tendon hypertrophy in humans following resistance training. Acta Physiol (Oxf) 2007; 191:111-21. [PMID: 17524067 DOI: 10.1111/j.1748-1716.2007.01714.x] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
AIM To examine if cross-sectional area (CSA) differs along the length of the human patellar tendon (PT), and if there is PT hypertrophy in response to resistance training. METHODS Twelve healthy young men underwent baseline and post-training assessments. Maximal isometric knee extension strength (MVC) was determined unilaterally in both legs. PT CSA was measured at the proximal-, mid- and distal PT level and quadriceps muscle CSA was measured at mid-thigh level using magnetic resonance imaging. Mechanical properties of the patellar tendons were determined using ultrasonography. Subsequently, subjects performed 12 weeks of heavy resistance knee extension training with one leg (Heavy-leg), and light resistance knee extension training with the other leg (Light-leg). RESULTS The MVC increased for heavy-leg (15 +/- 4%, P < 0.05), but not for light-leg (6 +/- 4%). Quadriceps CSA increased in heavy-legs (6 +/- 1%, P < 0.05) while unchanged in light-legs. Proximal PT CSA (104 +/- 4 mm(2)) was smaller than the mid-tendon CSA (118 +/- 3 mm(2)), which again was smaller than distal tendon CSA (127 +/- 2 mm(2), P < 0.05). Light-leg PT CSA increased by 7 +/- 3% (P < 0.05) at the proximal tendon level, but was otherwise unchanged. Heavy-leg PT CSA increased at the proximal and distal tendon levels by 6 +/- 3% and 4 +/- 2% respectively (P < 0.05), but was unchanged at the mid tendon level. PT stiffness increased in heavy-legs (P < 0.05) but was unchanged in light-legs. Modulus remained unchanged in both legs. CONCLUSIONS To our knowledge, this study is the first to report tendon hypertrophy following resistance training. Further, the data show that the human PT CSA varies along the length of the tendon.
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Affiliation(s)
- M Kongsgaard
- Institute of Sports Medicine Copenhagen, Bispebjerg Hospital, Copenhagen, Denmark.
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