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Rodrigues Junior CF, Murata GM, Gerlinger-Romero F, Nachbar RT, Marzuca-Nassr GN, Gorjão R, Vitzel KF, Hirabara SM, Pithon-Curi TC, Curi R. Changes in Skeletal Muscle Protein Metabolism Signaling Induced by Glutamine Supplementation and Exercise. Nutrients 2023; 15:4711. [PMID: 38004105 PMCID: PMC10674901 DOI: 10.3390/nu15224711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/30/2023] [Accepted: 11/01/2023] [Indexed: 11/26/2023] Open
Abstract
AIM To evaluate the effects of resistance exercise training (RET) and/or glutamine supplementation (GS) on signaling protein synthesis in adult rat skeletal muscles. METHODS The following groups were studied: (1) control, no exercise (C); (2) exercise, hypertrophy resistance exercise training protocol (T); (3) no exercise, supplemented with glutamine (G); and (4) exercise and supplemented with glutamine (GT). The rats performed hypertrophic training, climbing a vertical ladder with a height of 1.1 m at an 80° incline relative to the horizontal with extra weights tied to their tails. The RET was performed three days a week for five weeks. Each training session consisted of six ladder climbs. The extra weight load was progressively increased for each animal during each training session. The G groups received daily L-glutamine by gavage (one g per kilogram of body weight per day) for five weeks. The C group received the same volume of water during the same period. The rats were euthanized, and the extensor digitorum longus (EDL) muscles from both hind limbs were removed and immediately weighed. Glutamine and glutamate concentrations were measured, and histological, signaling protein contents, and mRNA expression analyses were performed. RESULTS Supplementation with free L-glutamine increased the glutamine concentration in the EDL muscle in the C group. The glutamate concentration was augmented in the EDL muscles from T rats. The EDL muscle mass did not change, but a significant rise was reported in the cross-sectional area (CSA) of the fibers in the three experimental groups. The levels of the phosphorylated proteins (pAkt/Akt, pp70S6K/p70S6K, p4E-BP1/4E-BP1, and pS6/S6 ratios) were significantly increased in EDL muscles of G rats, and the activation of p4E-BP1 was present in T rats. The fiber CSAs of the EDL muscles in T, G, and GT rats were increased compared to the C group. These changes were accompanied by a reduction in the 26 proteasome activity of EDL muscles from T rats. CONCLUSION Five weeks of GS and/or RET induced muscle hypertrophy, as indicated by the increased CSAs of the EDL muscle fibers. The increase in CSA was mediated via the upregulated phosphorylation of Akt, 4E-BP1, p70S6k, and S6 in G animals and 4E-BP1 in T animals. In the EDL muscles from T animals, a decrease in proteasome activity, favoring a further increase in the CSA of the muscle fibers, was reported.
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Affiliation(s)
- Carlos Flores Rodrigues Junior
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
| | - Gilson Masahiro Murata
- Divisions of Nephrology and Molecular Medicine, LIM-29, Department of Medicine, University of São Paulo, São Paulo 05508-220, Brazil;
| | | | - Renato Tadeu Nachbar
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
| | - Gabriel Nasri Marzuca-Nassr
- Departamento de Ciencias de la Rehabilitación, Facultad de Medicina, Universidad de La Frontera, Temuco 4811230, Chile;
- Interuniversity Center for Healthy Aging (Code RED21993), Talca 3460000, Chile
| | - Renata Gorjão
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Kaio Fernando Vitzel
- School of Health Sciences, Massey University (University of New Zealand), Auckland 0745, New Zealand;
| | - Sandro Massao Hirabara
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Tania Cristina Pithon-Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-220, Brazil; (C.F.R.J.); (T.C.P.-C.); (R.C.)
- Interdisciplinary Post-graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo 01506-000, Brazil;
- Butantan Institute, São Paulo 05585-000, Brazil
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Kang Y, Kim N, Lee Y, An X, Chung YS, Park YK. Muscle Mass Changes After Daily Consumption of Protein Mix Supplemented With Vitamin D in Adults Over 50 Years of Age: Subgroup Analysis According to the Serum 25(OH)D Levels of a Randomized Controlled Trial. Clin Nutr Res 2023; 12:184-198. [PMID: 37593214 PMCID: PMC10432158 DOI: 10.7762/cnr.2023.12.3.184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 05/14/2023] [Accepted: 06/22/2023] [Indexed: 08/19/2023] Open
Abstract
Early prevention of sarcopenia can be an important strategy for muscle maintenance, but most studies target subjects at slightly pre-sarcopenic state. Our previous paper describes the effect of protein supplements rich in leucine and vitamin D on muscle condition, and in this paper, we performed a sub-analysis to evaluate who benefitted the most in terms of improvement in muscle health. A 12-week randomized clinical trial of 120 healthy adults (aged 50 to 80) assigned to an intervention group (n = 60) or control group (n = 60) were analyzed. Subjects in the intervention group received, twice per day, a protein supplement containing (per serving) 800 IU of vitamin D, 20 g of protein (3 g of total leucine), 300 mg of calcium, 1.1 g of fat, and 2.5 g of carbohydrate. The subjects were classified into 'insufficient' and 'sufficient' groups at 25-hydroxyvitamin D (25[OH]D) value of 30 ng/mL. The skeletal muscle mass index normalized to the square of the skeletal muscle mass (SMM) height (kg/m2) increased significantly in the 'insufficient group' difference value of change between weeks 0 and 12 (Δ1.07 ± 2.20; p = 0.037). The SMM normalized by body weight (kg/kg, %) was higher, but not significantly, in the insufficient group (Δ0.38 ± 0.69; p = 0.050). For people with insufficient (serum 25[OH]D), supplemental intake of protein and vitamin D, calcium, and leucine and adequate energy intake increases muscle mass in middle-aged and older adults and would be likely to exert a beneficial effect on muscle health. Trial Registration Clinical Research Information Service Identifier: KCT0005111.
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Affiliation(s)
- Yeji Kang
- Department of Medical Nutrition, Kyung Hee University, Yongin 17104, Korea
| | - Namhee Kim
- Department of Medical Nutrition, Kyung Hee University, Yongin 17104, Korea
| | - Yunhwan Lee
- Department of Preventive Medicine and Public Health, Ajou University School of Medicine, Suwon 16499, Korea
| | - Xiangxue An
- R&D Group, Maeil Health Nutrition Co., Ltd., Pyeongtaek 17714, Korea
| | - Yoon-Sok Chung
- Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon 16499, Korea
| | - Yoo Kyoung Park
- Department of Medical Nutrition, Kyung Hee University, Yongin 17104, Korea
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Into the Tissues: Extracellular Matrix and Its Artificial Substitutes: Cell Signalling Mechanisms. Cells 2022; 11:cells11050914. [PMID: 35269536 PMCID: PMC8909573 DOI: 10.3390/cells11050914] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 02/06/2023] Open
Abstract
The existence of orderly structures, such as tissues and organs is made possible by cell adhesion, i.e., the process by which cells attach to neighbouring cells and a supporting substance in the form of the extracellular matrix. The extracellular matrix is a three-dimensional structure composed of collagens, elastin, and various proteoglycans and glycoproteins. It is a storehouse for multiple signalling factors. Cells are informed of their correct connection to the matrix via receptors. Tissue disruption often prevents the natural reconstitution of the matrix. The use of appropriate implants is then required. This review is a compilation of crucial information on the structural and functional features of the extracellular matrix and the complex mechanisms of cell–cell connectivity. The possibilities of regenerating damaged tissues using an artificial matrix substitute are described, detailing the host response to the implant. An important issue is the surface properties of such an implant and the possibilities of their modification.
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Whittaker J, Harris M. Low-carbohydrate diets and men's cortisol and testosterone: Systematic review and meta-analysis. Nutr Health 2022; 28:543-554. [PMID: 35254136 DOI: 10.1177/02601060221083079] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background: Low-carbohydrate diets may have endocrine effects, although individual studies are conflicting. Therefore, a review was conducted on the effects of low- versus high-carbohydrate diets on men's testosterone and cortisol. Methods: The review was registered on PROSPERO (CRD42021255957). The inclusion criteria were: intervention study, healthy adult males, and low-carbohydrate diet: ≤35% carbohydrate. Eight databases were searched from conception to May 2021. Cochrane's risk of bias tool was used for quality assessment. Random-effects, meta-analyses using standardized mean differences and 95% confidence intervals, were performed with Review Manager. Subgroup analyses were conducted for diet duration, protein intake, and exercise duration. Results: Twenty-seven studies were included, with a total of 309 participants. Short-term (<3 weeks), low- versus high-carbohydrate diets moderately increased resting cortisol (0.41 [0.16, 0.66], p < 0.01). Whereas, long-term (≥3 weeks), low-carbohydrate diets had no consistent effect on resting cortisol. Low- versus high-carbohydrate diets resulted in much higher post-exercise cortisol, after long-duration exercise (≥20 min): 0 h (0.78 [0.47, 1.1], p < 0.01), 1 h (0.81 [0.31, 1.31], p < 0.01), and 2 h (0.82 [0.33, 1.3], p < 0.01). Moderate-protein (<35%), low-carbohydrate diets had no consistent effect on resting total testosterone, however high-protein (≥35%), low-carbohydrate diets greatly decreased resting (-1.08 [-1.67, -0.48], p < 0.01) and post-exercise total testosterone (-1.01 [-2, -0.01] p = 0.05). Conclusions: Resting and post-exercise cortisol increase during the first 3 weeks of a low-carbohydrate diet. Afterwards, resting cortisol appears to return to baseline, whilst post-exercise cortisol remains elevated. High-protein diets cause a large decrease in resting total testosterone (∼5.23 nmol/L).
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Affiliation(s)
- Joseph Whittaker
- The School of Allied Health and Community, 8709University of Worcester, Worcester, UK
| | - Miranda Harris
- The School of Allied Health and Community, 8709University of Worcester, Worcester, UK
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Chapman S, Chung HC, Rawcliffe AJ, Izard R, Smith L, Roberts JD. Does Protein Supplementation Support Adaptations to Arduous Concurrent Exercise Training? A Systematic Review and Meta-Analysis with Military Based Applications. Nutrients 2021; 13:1416. [PMID: 33922458 PMCID: PMC8145048 DOI: 10.3390/nu13051416] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/16/2021] [Accepted: 04/20/2021] [Indexed: 12/11/2022] Open
Abstract
We evaluated the impact of protein supplementation on adaptations to arduous concurrent training in healthy adults with potential applications to individuals undergoing military training. Peer-reviewed papers published in English meeting the population, intervention, comparison and outcome criteria were included. Database searches were completed in PubMed, Web of science and SPORTDiscus. Study quality was evaluated using the COnsensus based standards for the selection of health status measurement instruments checklist. Of 11 studies included, nine focused on performance, six on body composition and four on muscle recovery. Cohen's d effect sizes showed that protein supplementation improved performance outcomes in response to concurrent training (ES = 0.89, 95% CI = 0.08-1.70). When analysed separately, improvements in muscle strength (SMD = +4.92 kg, 95% CI = -2.70-12.54 kg) were found, but not in aerobic endurance. Gains in fat-free mass (SMD = +0.75 kg, 95% CI = 0.44-1.06 kg) and reductions in fat-mass (SMD = -0.99, 95% CI = -1.43-0.23 kg) were greater with protein supplementation. Most studies did not report protein turnover, nitrogen balance and/or total daily protein intake. Therefore, further research is warranted. However, our findings infer that protein supplementation may support lean-mass accretion and strength gains during arduous concurrent training in physical active populations, including military recruits.
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Affiliation(s)
- Shaun Chapman
- HQ Army Recruiting and Initial Training Command, UK Ministry of Defence, Upavon, Wiltshire SN9 6BE, UK;
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge CB1 1PT, UK; (H.C.C.); (L.S.); (J.D.R.)
| | - Henry C. Chung
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge CB1 1PT, UK; (H.C.C.); (L.S.); (J.D.R.)
| | - Alex J. Rawcliffe
- HQ Army Recruiting and Initial Training Command, UK Ministry of Defence, Upavon, Wiltshire SN9 6BE, UK;
| | - Rachel Izard
- Defence Science and Technology, Porton Down, UK Ministry of Defence, Salisbury, Wiltshire SP4 0JQ, UK;
| | - Lee Smith
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge CB1 1PT, UK; (H.C.C.); (L.S.); (J.D.R.)
| | - Justin D. Roberts
- Cambridge Centre for Sport and Exercise Sciences, School of Psychology and Sport Science, Anglia Ruskin University, East Road, Cambridge CB1 1PT, UK; (H.C.C.); (L.S.); (J.D.R.)
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Stretton C, Pugh JN, McDonagh B, McArdle A, Close GL, Jackson MJ. 2-Cys peroxiredoxin oxidation in response to hydrogen peroxide and contractile activity in skeletal muscle: A novel insight into exercise-induced redox signalling? Free Radic Biol Med 2020; 160:199-207. [PMID: 32784030 PMCID: PMC7718083 DOI: 10.1016/j.freeradbiomed.2020.06.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/05/2020] [Accepted: 06/06/2020] [Indexed: 12/15/2022]
Abstract
Skeletal muscle generates superoxide during contractions which is rapidly converted to H2O2. This molecule has been proposed to activate signalling pathways and transcription factors that regulate key adaptive responses to exercise but the concentration of H2O2 required to oxidise and activate key signalling proteins in vitro is much higher than the intracellular concentration in muscle fibers following exercise. We hypothesised that Peroxiredoxins (Prx), which reacts with H2O2 at the low intracellular concentrations found in muscle, would be rapidly oxidised in contracting muscle and hence potentially transmit oxidising equivalents to downstream signalling proteins as a method for their oxidation and activation. The aim of this study was to characterise the effects of muscle contractile activity on the oxidation of Prx1, 2 and 3 and determine if these were affected by aging. Prx1, 2 and 3 were all rapidly and reversibly oxidised following treatment with low micromolar concentrations of H2O2 in C2C12 myotubes and also in isolated mature flexor digitalis brevis fibers from adult mice following a protocol of repeated isometric contractions. Significant oxidation of Prx2 was seen within 1 min (i.e. after 12 contractions), whereas significant oxidation was seen after 2 min for Prx1 and 3. In muscle fibers from old mice, Prx2 oxidation was significantly attenuated following contractile activity. Thus we show for the first time that Prx are rapidly and reversibly oxidised in response to contractile activity in skeletal muscle and hypothesise that these proteins act as effectors of muscle redox signalling pathways which are key to adaptations to exercise that are attenuated during aging.
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Affiliation(s)
- Clare Stretton
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool and MRC- Arthritis Research UK Centre for Integrated Research Into Musculoskeletal Ageing (CIMA), UK
| | - Jamie N Pugh
- School of Sport and Exercise Sciences, Tom Reilly Building, Byrom Street, Liverpool John Moores University, Liverpool, UK
| | - Brian McDonagh
- Discipline of Physiology, School of Medicine, National University of Ireland Galway, Ireland
| | - Anne McArdle
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool and MRC- Arthritis Research UK Centre for Integrated Research Into Musculoskeletal Ageing (CIMA), UK
| | - Graeme L Close
- School of Sport and Exercise Sciences, Tom Reilly Building, Byrom Street, Liverpool John Moores University, Liverpool, UK
| | - Malcolm J Jackson
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool and MRC- Arthritis Research UK Centre for Integrated Research Into Musculoskeletal Ageing (CIMA), UK.
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7
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Kang Y, Kim N, Choi YJ, Lee Y, Yun J, Park SJ, Park HS, Chung YS, Park YK. Leucine-Enriched Protein Supplementation Increases Lean Body Mass in Healthy Korean Adults Aged 50 Years and Older: A Randomized, Double-Blind, Placebo-Controlled Trial. Nutrients 2020; 12:E1816. [PMID: 32570811 PMCID: PMC7353448 DOI: 10.3390/nu12061816] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 12/22/2022] Open
Abstract
Early prevention of sarcopenia could be an important strategy for muscle retention, but most studies have focused on subjects aged 65 or older. Therefore, in this study we investigated the effects of leucine-enriched protein supplementation on muscle condition in a sample including late middle-aged adults. A 12-week intervention was performed for 120 healthy community-dwelling adults by providing either leucine-enriched protein supplement [leucine 3 g, protein mixture (casein 50% + whey 40% + soy 10%) 17 g, vitamin D 800IU (20 µg), calcium 300 mg, fat 1.1 g, carbohydrate 2.5 g] or isocaloric carbohydrate supplement twice per day. Appendicular skeletal muscle mass index (ASMI) and lean body mass (LBM) were measured by dual-energy X-ray absorptiometry. A total of 111 participants completed the study, with a dropout rate of 9.2%. LBM normalized by height and body weight (LBM/Wt) was significantly increased (p < 0.001) in the intervention group (0 wk: 633.9 ± 8.5 vs. 12 wk 636.9 ± 8.4 in the intervention group; 0 wk: 638.6 ± 8.3 vs. 12 wk: 632.9 ± 8.1 in the control group). In subgroup analyses, significant differences remained only in subjects between 50 and 64 years of age. We concluded that leucine-enriched protein supplementation can have beneficial effects by preventing muscle loss, mainly for late middle-aged adults.
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Affiliation(s)
- Yeji Kang
- Department of Medical Nutrition, Kyung Hee University, Yong-in 17104, Korea; (Y.K.); (N.K.)
| | - Namhee Kim
- Department of Medical Nutrition, Kyung Hee University, Yong-in 17104, Korea; (Y.K.); (N.K.)
| | - Yong Jun Choi
- Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon 16499, Korea;
| | - Yunhwan Lee
- Department of Preventive Medicine and Public Health, Ajou University School of Medicine, Suwon 16499, Korea; (Y.L.); (J.Y.)
| | - Jihye Yun
- Department of Preventive Medicine and Public Health, Ajou University School of Medicine, Suwon 16499, Korea; (Y.L.); (J.Y.)
| | - Seok Jun Park
- Health & Nutrition R&D Group, Maeil Dairies Co., Ltd., Pyeongtaek-si 17714, Korea; (S.J.P.); (H.S.P.)
| | - Hyoung Su Park
- Health & Nutrition R&D Group, Maeil Dairies Co., Ltd., Pyeongtaek-si 17714, Korea; (S.J.P.); (H.S.P.)
| | - Yoon-Sok Chung
- Department of Endocrinology and Metabolism, Ajou University School of Medicine, Suwon 16499, Korea;
| | - Yoo Kyoung Park
- Department of Medical Nutrition, Kyung Hee University, Yong-in 17104, Korea; (Y.K.); (N.K.)
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Gaston AF, Marti Peiro A, Hapkova I, Durand F. Exploring physiological parameters in ski mountaineering during world cup races. INT J PERF ANAL SPOR 2019. [DOI: 10.1080/24748668.2019.1597399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Anne-Fleur Gaston
- Laboratoire Européen Performance Santé Altitude, Université de Perpignan Via Domitia, Font-Romeu, France
- Unité de Physiologie des Exercices et Activités en Conditions Extrêmes, Institut de Recherche Biomédicale des Armées, Brétigny-sur-Orge, France
| | - Adrià Marti Peiro
- Laboratoire Européen Performance Santé Altitude, Université de Perpignan Via Domitia, Font-Romeu, France
- Nässjö Basket, Nässjö, Sweden
| | - Ilona Hapkova
- Laboratoire Européen Performance Santé Altitude, Université de Perpignan Via Domitia, Font-Romeu, France
- ECOWAS Campus, Lomé, Togo
| | - Fabienne Durand
- Laboratoire Européen Performance Santé Altitude, Université de Perpignan Via Domitia, Font-Romeu, France
- Catedra de Medicina de Muntanya i del Medi Natural i de Simulacio Clinica, Universitat de Girona, Girona, Spain
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You JS, McNally RM, Jacobs BL, Privett RE, Gundermann DM, Lin KH, Steinert ND, Goodman CA, Hornberger TA. The role of raptor in the mechanical load-induced regulation of mTOR signaling, protein synthesis, and skeletal muscle hypertrophy. FASEB J 2019; 33:4021-4034. [PMID: 30509128 PMCID: PMC6404572 DOI: 10.1096/fj.201801653rr] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/05/2018] [Indexed: 12/21/2022]
Abstract
It is well known that an increase in mechanical loading can induce skeletal muscle hypertrophy, and a long standing model in the field indicates that mechanical loads induce hypertrophy via a mechanism that requires signaling through the mechanistic target of rapamycin complex 1 (mTORC1). Specifically, it has been widely proposed that mechanical loads activate signaling through mTORC1 and that this, in turn, promotes an increase in the rate of protein synthesis and the subsequent hypertrophic response. However, this model is based on a number of important assumptions that have not been rigorously tested. In this study, we created skeletal muscle specific and inducible raptor knockout mice to eliminate signaling by mTORC1, and with these mice we were able to directly demonstrate that mechanical stimuli can activate signaling by mTORC1, and that mTORC1 is necessary for mechanical load-induced hypertrophy. Surprisingly, however, we also obtained multiple lines of evidence that indicate that mTORC1 is not required for a mechanical load-induced increase in the rate of protein synthesis. This observation highlights an important shortcoming in our understanding of how mechanical loads induce hypertrophy and illustrates that additional mTORC1-independent mechanisms play a critical role in this process.-You, J.-S., McNally, R. M., Jacobs, B. L., Privett, R. E., Gundermann, D. M., Lin, K.-H., Steinert, N. D., Goodman, C. A., Hornberger, T. A. The role of raptor in the mechanical load-induced regulation of mTOR signaling, protein synthesis, and skeletal muscle hypertrophy.
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Affiliation(s)
- Jae-Sung You
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Rachel M. McNally
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Brittany L. Jacobs
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Rachel E. Privett
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - David M. Gundermann
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Kuan-Hung Lin
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Nate D. Steinert
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
| | - Craig A. Goodman
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
- Institute of Health and Sport, Victoria University, Melbourne, Victoria, Australia
- Australian Institute for Musculoskeletal Science, Victoria University, St. Albans, Victoria, Australia
| | - Troy A. Hornberger
- Department of Comparative Biosciences, University of Wisconsin–Madison, Madison, Wisconsin, USA
- School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA
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Carbone JW, McClung JP, Pasiakos SM. Recent Advances in the Characterization of Skeletal Muscle and Whole-Body Protein Responses to Dietary Protein and Exercise during Negative Energy Balance. Adv Nutr 2019; 10:70-79. [PMID: 30596808 PMCID: PMC6370268 DOI: 10.1093/advances/nmy087] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/01/2018] [Indexed: 01/02/2023] Open
Abstract
In a review published in 2012, we concluded that higher-protein diets preserve muscle mass during energy deficit via stimulated mammalian target of rapamycin complex 1 signaling, coincident increased muscle protein synthesis (PS), inhibited ubiquitin-mediated proteolysis, and suppressed muscle protein breakdown (PB). Since then, there have been significant advances in understanding the fundamental effects of higher-protein diets, with or without exercise training, on muscle and whole-body protein homeostasis during negative energy balance. Therefore, an update on the evolution of this field of research is warranted to better inform recommendations on best practices for healthy weight loss and muscle preservation. We will review the most recent studies examining the effects of higher-protein diets and negative energy balance on body composition, muscle PS, muscle PB, associated intracellular regulatory pathway activities, and whole-body protein homeostasis. In addition to critically analyzing contemporary findings, knowledge gaps and opportunities for continued research will be identified. Overall, the newest research confirms that consuming higher-protein diets, particularly when coupled with resistance exercise, preserves muscle mass and maintains whole-body protein homeostasis during moderate energy deficits (i.e., normal weight loss). However, these newer findings also indicate that as the magnitude of energy deficit increases, the efficacy of higher-protein diets for mitigating losses of fat-free mass is diminished. Further, recent results suggest that alterations in muscle PS, more so than muscle PB, may be primarily responsible for changes in muscle mass that occur in response to negative energy balance.
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Affiliation(s)
- John W Carbone
- School of Health Sciences, Eastern Michigan University, Ypsilanti, MI,Address correspondence to JWC (e-mail: )
| | - James P McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA
| | - Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA
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Margolis LM, Berryman CE, Murphy NE, Carrigan CT, Young AJ, Carbone JW, Pasiakos SM. PI3K-AKT-FOXO1 pathway targeted by skeletal muscle microRNA to suppress proteolytic gene expression in response to carbohydrate intake during aerobic exercise. Physiol Rep 2018; 6:e13931. [PMID: 30548426 PMCID: PMC6289907 DOI: 10.14814/phy2.13931] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 11/06/2018] [Indexed: 11/24/2022] Open
Abstract
Ingesting protein and carbohydrate together during aerobic exercise suppresses the expression of specific skeletal muscle microRNA and promotes muscle hypertrophy. Determining whether there are independent effects of carbohydrate and protein on microRNA will allow for a clearer understanding of the mechanistic role microRNA serve in regulating skeletal muscle protein synthetic and proteolytic responses to nutrition and exercise. This study determined skeletal muscle microRNA responses to aerobic exercise with or without carbohydrate, and recovery whey protein (WP). Seventeen males were randomized to consume carbohydrate (CHO; 145 g; n = 9) or non-nutritive control (CON; n = 8) beverages during exercise. Muscle was collected before (BASE) and after 80 min of steady-state exercise (1.7 ± 0.3 V̇O2 L·min-1 ) followed by a 2-mile time trial (17.9 ± 3.5 min; POST), and 3-h into recovery after consuming WP (25 g; REC). RT-qPCR was used to determine microRNA and mRNA expression. Bioinformatics analysis was conducted using the mirPath software. Western blotting was used to assess protein signaling. The expression of six microRNA (miR-19b-3p, miR-99a-5p, miR-100-5p, miR-222-3p, miR-324-3p, and miR-486-5p) were higher (P < 0.05) in CHO compared to CON, all of which target the PI3K-AKT, ubiquitin proteasome, FOXO, and mTORC1 pathways. p-AKTThr473 and p-FOXO1Thr24 were higher (P < 0.05) in POST CHO compared to CON. The expression of PTEN was lower (P < 0.05) in REC CHO than CON, while MURF1 was lower (P < 0.05) POST CHO than CON. These findings suggest the mechanism by which microRNA facilitate skeletal muscle adaptations in response to exercise with carbohydrate and protein feeding is by inhibiting markers of proteolysis.
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Affiliation(s)
- Lee M. Margolis
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
- Oak Ridge Institute of Science and EducationOak RidgeTennessee
| | - Claire E. Berryman
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
- Oak Ridge Institute of Science and EducationOak RidgeTennessee
- Department of Nutrition, Food, and Exercise SciencesFlorida State UniversityTallahasseeFlorida
| | - Nancy E. Murphy
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
| | - Christopher T. Carrigan
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
| | - Andrew J. Young
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
- Oak Ridge Institute of Science and EducationOak RidgeTennessee
| | - John W. Carbone
- Oak Ridge Institute of Science and EducationOak RidgeTennessee
- School of Health SciencesEastern Michigan UniversityYpsilantiMichigan
| | - Stefan M. Pasiakos
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusetts
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Rebelo-Marques A, De Sousa Lages A, Andrade R, Ribeiro CF, Mota-Pinto A, Carrilho F, Espregueira-Mendes J. Aging Hallmarks: The Benefits of Physical Exercise. Front Endocrinol (Lausanne) 2018; 9:258. [PMID: 29887832 PMCID: PMC5980968 DOI: 10.3389/fendo.2018.00258] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 05/03/2018] [Indexed: 12/15/2022] Open
Abstract
World population has been continuously increasing and progressively aging. Aging is characterized by a complex and intraindividual process associated with nine major cellular and molecular hallmarks, namely, genomic instability, telomere attrition, epigenetic alterations, a loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. This review exposes the positive antiaging impact of physical exercise at the cellular level, highlighting its specific role in attenuating the aging effects of each hallmark. Exercise should be seen as a polypill, which improves the health-related quality of life and functional capabilities while mitigating physiological changes and comorbidities associated with aging. To achieve a framework of effective physical exercise interventions on aging, further research on its benefits and the most effective strategies is encouraged.
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Affiliation(s)
- Alexandre Rebelo-Marques
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
- Clínica do Dragão, Espregueira-Mendes Sports Centre – FIFA Medical Centre of Excellence, Porto, Portugal
- Dom Henrique Research Centre, Porto, Portugal
| | - Adriana De Sousa Lages
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
- Endocrinology, Diabetes and Metabolism Department, Coimbra Hospital and University Center, Coimbra, Portugal
| | - Renato Andrade
- Clínica do Dragão, Espregueira-Mendes Sports Centre – FIFA Medical Centre of Excellence, Porto, Portugal
- Dom Henrique Research Centre, Porto, Portugal
- Faculty of Sports, University of Porto, Porto, Portugal
| | | | | | - Francisco Carrilho
- Endocrinology, Diabetes and Metabolism Department, Coimbra Hospital and University Center, Coimbra, Portugal
| | - João Espregueira-Mendes
- Clínica do Dragão, Espregueira-Mendes Sports Centre – FIFA Medical Centre of Excellence, Porto, Portugal
- Dom Henrique Research Centre, Porto, Portugal
- 3B’s Research Group—Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Guimarães, Portugal
- ICVS/3B’s–PT Government Associate Laboratory, Guimarães, Braga, Portugal
- Orthopaedics Department of Minho University, Minho, Portugal
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13
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Margolis LM, McClung HL, Murphy NE, Carrigan CT, Pasiakos SM. Skeletal Muscle myomiR Are Differentially Expressed by Endurance Exercise Mode and Combined Essential Amino Acid and Carbohydrate Supplementation. Front Physiol 2017; 8:182. [PMID: 28386239 PMCID: PMC5362638 DOI: 10.3389/fphys.2017.00182] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 03/09/2017] [Indexed: 11/13/2022] Open
Abstract
Skeletal muscle microRNAs (myomiR) expression is modulated by exercise, however, the influence of endurance exercise mode, combined with essential amino acid and carbohydrate (EAA+CHO) supplementation are not well defined. This study determined the effects of weighted versus non-weighted endurance exercise, with or without EAA+CHO ingestion on myomiR expression and their association with muscle protein synthesis (MPS). Twenty five adults performed 90 min of metabolically-matched (2.2 VO2 L·m-1) load carriage (LC; performed on a treadmill wearing a vest equal to 30% of individual body mass) or cycle ergometry (CE) exercise, during which EAA+CHO (10 g EAA and 46 g CHO) or non-nutritive control (CON) drinks were consumed. Expression of myomiR (RT-qPCR) were determined at rest (PRE), immediately post-exercise (POST), and 3 h into recovery (REC). Muscle protein synthesis (2H5-phenylalanine) was measured during exercise and recovery. Relative to PRE, POST, and REC expression of miR-1-3p, miR-206, miR-208a-5, and miR-499 was lower (P < 0.05) for LC compared to CE, regardless of dietary treatment. Independent of exercise mode, miR-1-3p and miR-208a-5p expression were lower (P < 0.05) after ingesting EAA+CHO compared to CON. Expression of miR-206 was highest for CE-CON than any other treatment (exercise-by-drink, P < 0.05). Common targets of differing myomiR were identified as markers within mTORC1 signaling, and miR-206 and miR-499 were inversely associated with MPS rates immediately post-exercise. These findings suggest the alterations in myomiR expression between exercise mode and EAA+CHO intake may in part be due to differing MPS modulation immediately post-exercise.
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Affiliation(s)
- Lee M Margolis
- Military Nutrition Division, US Army Research Institute of Environmental MedicineNatick, MA, USA; Oak Ridge Institute for Science and EducationOak Ridge, TN, USA
| | - Holly L McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
| | - Nancy E Murphy
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
| | - Christopher T Carrigan
- Military Nutrition Division, US Army Research Institute of Environmental MedicineNatick, MA, USA; Oak Ridge Institute for Science and EducationOak Ridge, TN, USA
| | - Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
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14
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Margolis LM, Rivas DA, Berrone M, Ezzyat Y, Young AJ, McClung JP, Fielding RA, Pasiakos SM. Prolonged Calorie Restriction Downregulates Skeletal Muscle mTORC1 Signaling Independent of Dietary Protein Intake and Associated microRNA Expression. Front Physiol 2016; 7:445. [PMID: 27761114 PMCID: PMC5050214 DOI: 10.3389/fphys.2016.00445] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 09/20/2016] [Indexed: 01/18/2023] Open
Abstract
Short-term (5-10 days) calorie restriction (CR) downregulates muscle protein synthesis, with consumption of a high protein-based diet attenuating this decline. Benefit of increase protein intake is believed to be due to maintenance of amino acid-mediated anabolic signaling through the mechanistic target of rapamycin complex 1 (mTORC1), however, there is limited evidence to support this contention. The purpose of this investigation was to determine the effects of prolonged CR and high protein diets on skeletal muscle mTORC1 signaling and expression of associated microRNA (miR). Twelve-week old male Sprague Dawley rats consumed ad libitum (AL) or calorie restricted (CR; 40%) adequate (10%, AIN-93M) or high (32%) protein milk-based diets for 16 weeks. Body composition was determined using dual energy X-ray absorptiometry and muscle protein content was calculated from muscle homogenate protein concentrations expressed relative to fat-free mass to estimate protein content. Western blot and RT-qPCR were used to determine mTORC1 signaling and mRNA and miR expression in fasted mixed gastrocnemius. Independent of dietary protein intake, muscle protein content was 38% lower (P < 0.05) in CR compared to AL. Phosphorylation and total Akt, mTOR, rpS6, and p70S6K were lower (P < 0.05) in CR vs. AL, and total rpS6 was associated with muscle protein content (r = 0.64, r2 = 0.36). Skeletal muscle miR expression was not altered by either energy or protein intake. This study provides evidence that chronic CR attenuates muscle protein content by downregulating mTORC1 signaling. This response is independent of skeletal muscle miR and dietary protein.
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Affiliation(s)
- Lee M Margolis
- Nutrition, Exercise, Physiology, and Sarcopenia Laboratory, U.S. Department of Agriculture Jean Mayer Human Nutrition Research Center on Aging, Tufts UniversityBoston, MA, USA; Military Nutrition Division, US Army Research Institute of Environmental MedicineNatick, MA, USA
| | - Donato A Rivas
- Nutrition, Exercise, Physiology, and Sarcopenia Laboratory, U.S. Department of Agriculture Jean Mayer Human Nutrition Research Center on Aging, Tufts University Boston, MA, USA
| | - Maria Berrone
- Nutrition, Exercise, Physiology, and Sarcopenia Laboratory, U.S. Department of Agriculture Jean Mayer Human Nutrition Research Center on Aging, Tufts University Boston, MA, USA
| | - Yassine Ezzyat
- Nutrition, Exercise, Physiology, and Sarcopenia Laboratory, U.S. Department of Agriculture Jean Mayer Human Nutrition Research Center on Aging, Tufts University Boston, MA, USA
| | - Andrew J Young
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
| | - James P McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
| | - Roger A Fielding
- Nutrition, Exercise, Physiology, and Sarcopenia Laboratory, U.S. Department of Agriculture Jean Mayer Human Nutrition Research Center on Aging, Tufts University Boston, MA, USA
| | - Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine Natick, MA, USA
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15
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Effect of Oral Branched-Chain Amino Acid Supplementation Prior to Resistance Exercise on Metabolic Hormones, Plasma Amino Acids, and Serum Indices of Muscle Damage in the Recovery Period. TOP CLIN NUTR 2016. [DOI: 10.1097/tin.0000000000000085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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16
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Schmidt JA, Rinaldi S, Scalbert A, Ferrari P, Achaintre D, Gunter MJ, Appleby PN, Key TJ, Travis RC. Plasma concentrations and intakes of amino acids in male meat-eaters, fish-eaters, vegetarians and vegans: a cross-sectional analysis in the EPIC-Oxford cohort. Eur J Clin Nutr 2016; 70:306-12. [PMID: 26395436 PMCID: PMC4705437 DOI: 10.1038/ejcn.2015.144] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 07/01/2015] [Accepted: 07/21/2015] [Indexed: 01/28/2023]
Abstract
BACKGROUND/OBJECTIVES We aimed to investigate the differences in plasma concentrations and in intakes of amino acids between male meat-eaters, fish-eaters, vegetarians and vegans in the Oxford arm of the European Prospective Investigation into Cancer and Nutrition. SUBJECTS/METHODS This cross-sectional analysis included 392 men, aged 30-49 years. Plasma amino acid concentrations were measured with a targeted metabolomic approach using mass spectrometry, and dietary intake was assessed using a food frequency questionnaire. Differences between diet groups in mean plasma concentrations and intakes of amino acids were examined using analysis of variance, controlling for potential confounding factors and multiple testing. RESULTS In plasma, concentrations of 6 out of 21 amino acids varied significantly by diet group, with differences of -13% to +16% between meat-eaters and vegans. Concentrations of methionine, tryptophan and tyrosine were highest in fish-eaters and vegetarians, followed by meat-eaters, and lowest in vegans. A broadly similar pattern was seen for lysine, whereas alanine concentration was highest in fish-eaters and lowest in meat-eaters. For glycine, vegans had the highest concentration and meat-eaters the lowest. Intakes of all 18 dietary amino acids differed by diet group; for the majority of these, intake was highest in meat-eaters followed by fish-eaters, then vegetarians and lowest in vegans (up to 47% lower than in meat-eaters). CONCLUSIONS Men belonging to different habitual diet groups have significantly different plasma concentrations of lysine, methionine, tryptophan, alanine, glycine and tyrosine. However, the differences in plasma concentrations were less marked than and did not necessarily mirror those seen for amino acid intakes.
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Affiliation(s)
- J A Schmidt
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - S Rinaldi
- International Agency for Research on Cancer, Lyon, France
| | - A Scalbert
- International Agency for Research on Cancer, Lyon, France
| | - P Ferrari
- International Agency for Research on Cancer, Lyon, France
| | - D Achaintre
- International Agency for Research on Cancer, Lyon, France
| | - M J Gunter
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
| | - P N Appleby
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - T J Key
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - R C Travis
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
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17
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Garatachea N, Pareja-Galeano H, Sanchis-Gomar F, Santos-Lozano A, Fiuza-Luces C, Morán M, Emanuele E, Joyner MJ, Lucia A. Exercise attenuates the major hallmarks of aging. Rejuvenation Res 2016; 18:57-89. [PMID: 25431878 DOI: 10.1089/rej.2014.1623] [Citation(s) in RCA: 242] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Regular exercise has multi-system anti-aging effects. Here we summarize how exercise impacts the major hallmarks of aging. We propose that, besides searching for novel pharmaceutical targets of the aging process, more research efforts should be devoted to gaining insights into the molecular mediators of the benefits of exercise and to implement effective exercise interventions for elderly people.
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Affiliation(s)
- Nuria Garatachea
- 1 Faculty of Health and Sport Science, University of Zaragoza , Huesca, Spain
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18
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Pasiakos SM, McClung HL, Margolis LM, Murphy NE, Lin GG, Hydren JR, Young AJ. Human Muscle Protein Synthetic Responses during Weight-Bearing and Non-Weight-Bearing Exercise: A Comparative Study of Exercise Modes and Recovery Nutrition. PLoS One 2015; 10:e0140863. [PMID: 26474292 PMCID: PMC4608805 DOI: 10.1371/journal.pone.0140863] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 10/01/2015] [Indexed: 12/05/2022] Open
Abstract
Effects of conventional endurance (CE) exercise and essential amino acid (EAA) supplementation on protein turnover are well described. Protein turnover responses to weighted endurance exercise (i.e., load carriage, LC) and EAA may differ from CE, because the mechanical forces and contractile properties of LC and CE likely differ. This study examined muscle protein synthesis (MPS) and whole-body protein turnover in response to LC and CE, with and without EAA supplementation, using stable isotope amino acid tracer infusions. Forty adults (mean ± SD, 22 ± 4 y, 80 ± 10 kg, VO2peak 4.0 ± 0.5 L∙min-1) were randomly assigned to perform 90 min, absolute intensity-matched (2.2 ± 0.1 VO2 L∙m-1) LC (performed on a treadmill wearing a vest equal to 30% of individual body mass, mean ± SD load carried 24 ± 3 kg) or CE (cycle ergometry performed at the same absolute VO2 as LC) exercise, during which EAA (10 g EAA, 3.6 g leucine) or control (CON, non-nutritive) drinks were consumed. Mixed-muscle and myofibrillar MPS were higher during exercise for LC than CE (mode main effect, P < 0.05), independent of dietary treatment. EAA enhanced mixed-muscle and sarcoplasmic MPS during exercise, regardless of mode (drink main effect, P < 0.05). Mixed-muscle and sarcoplasmic MPS were higher in recovery for LC than CE (mode main effect, P < 0.05). No other differences or interactions (mode x drink) were observed. However, EAA attenuated whole-body protein breakdown, increased amino acid oxidation, and enhanced net protein balance in recovery compared to CON, regardless of exercise mode (P < 0.05). These data show that, although whole-body protein turnover responses to absolute VO2-matched LC and CE are the same, LC elicited a greater muscle protein synthetic response than CE.
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Affiliation(s)
- Stefan M. Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
- * E-mail:
| | - Holly L. McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
| | - Lee M. Margolis
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
| | - Nancy E. Murphy
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
| | - Gregory G. Lin
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
| | - Jay R. Hydren
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
| | - Andrew J. Young
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, United States of America
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19
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The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review. Sports Med 2015; 45:111-31. [PMID: 25169440 DOI: 10.1007/s40279-014-0242-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Protein supplements are frequently consumed by athletes and recreationally active adults to achieve greater gains in muscle mass and strength and improve physical performance. OBJECTIVE This review provides a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements accelerate gains in muscle mass and strength resulting in improvements in aerobic and anaerobic power. Evidence statements were created based on an accepted strength of recommendation taxonomy. DATA SOURCES English language articles were searched through PubMed and Google Scholar using protein and supplements together with performance, exercise, strength, and muscle, alone or in combination as keywords. Additional articles were retrieved from reference lists found in these papers. STUDY SELECTION Studies recruiting healthy adults between 18 and 50 years of age that evaluated the effects of protein supplements alone or in combination with carbohydrate on a performance metric (e.g., one repetition maximum or isometric or isokinetic muscle strength), metrics of body composition, or measures of aerobic or anaerobic power were included in this review. The literature search identified 32 articles which incorporated test metrics that dealt exclusively with changes in muscle mass and strength, 5 articles that implemented combined resistance and aerobic training or followed participants during their normal sport training programs, and 1 article that evaluated changes in muscle oxidative enzymes and maximal aerobic power. STUDY APPRAISAL AND SYNTHESIS METHODS All papers were read in detail, and examined for experimental design confounders such as dietary monitoring, history of physical training (i.e., trained and untrained), and the number of participants studied. Studies were also evaluated based on the intensity, frequency, and duration of training, the type and timing of protein supplementation, and the sensitivity of the test metrics. RESULTS For untrained individuals, consuming supplemental protein likely has no impact on lean mass and muscle strength during the initial weeks of resistance training. However, as the duration, frequency, and volume of resistance training increase, protein supplementation may promote muscle hypertrophy and enhance gains in muscle strength in both untrained and trained individuals. Evidence also suggests that protein supplementation may accelerate gains in both aerobic and anaerobic power. LIMITATIONS To demonstrate measureable gains in strength and performance with exercise training and protein supplementation, many of the studies reviewed recruited untrained participants. Since skeletal muscle responses to exercise and protein supplementation differ between trained and untrained individuals, findings are not easily generalized for all consumers who may be considering the use of protein supplements. CONCLUSIONS This review suggests that protein supplementation may enhance muscle mass and performance when the training stimulus is adequate (e.g., frequency, volume, duration), and dietary intake is consistent with recommendations for physically active individuals.
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Margolis LM, Rivas DA. Implications of exercise training and distribution of protein intake on molecular processes regulating skeletal muscle plasticity. Calcif Tissue Int 2015; 96:211-21. [PMID: 25348078 PMCID: PMC6691734 DOI: 10.1007/s00223-014-9921-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/15/2014] [Indexed: 12/19/2022]
Abstract
To optimize its function, skeletal muscle exhibits exceptional plasticity and possesses the fundamental capacity to adapt its metabolic and contractile properties in response to various external stimuli (e.g., external loading, nutrient availability, and humoral factors). The adaptability of skeletal muscle, along with its relatively large mass and high metabolic rate, makes this tissue an important contributor to whole body health and mobility. This adaptational process includes changes in the number, size, and structural/functional properties of the myofibers. The adaptations of skeletal muscle to exercise are highly interrelated with dietary intake, particularly dietary protein, which has been shown to further potentiate exercise training-induced adaptations. Understanding the molecular adaptation of skeletal muscle to exercise and protein consumption is vital to elicit maximum benefit from exercise training to improve human performance and health. In this review, we will provide an overview of the molecular pathways regulating skeletal muscle adaptation to exercise and protein, and discuss the role of subsequent timing of nutrient intake following exercise.
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Affiliation(s)
- Lee M Margolis
- Nutrition, Exercise Physiology and Sarcopenia Laboratory, Jean Mayer USDA Human Nutrition Research Center On Aging, Tufts University, 711 Washington Street, Boston, MA, 02111, USA
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21
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Beto JA. The role of calcium in human aging. Clin Nutr Res 2015; 4:1-8. [PMID: 25713787 PMCID: PMC4337919 DOI: 10.7762/cnr.2015.4.1.1] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Revised: 12/27/2014] [Accepted: 12/29/2014] [Indexed: 12/11/2022] Open
Abstract
Calcium is an essential nutrient that is necessary for many functions in human health. Calcium is the most abundant mineral in the body with 99% found in teeth and bone. Only 1% is found in serum. The serum calcium level is tightly monitored to remain within normal range by a complex metabolic process. Calcium metabolism involves other nutrients including protein, vitamin D, and phosphorus. Bone formation and maintenance is a lifelong process. Early attention to strong bones in childhood and adulthood will provide more stable bone mass during the aging years. Research has shown that adequate calcium intake can reduce the risk of fractures, osteoporosis, and diabetes in some populations. The dietary requirements of calcium and other collaborative nutrients vary slightly around the world. Lactose intolerance due to lactase deficiency is a common cause of low calcium intake. Strategies will be discussed for addressing this potential barrier to adequate intake. The purpose of this narrative review is a) to examine the role of calcium in human health, b) to compare nutrient requirements for calcium across lifecycle groups and global populations, c) to review relationships between calcium intake, chronic disease risk, and fractures, and d) to discuss strategies to address diet deficiencies and lactose intolerance.
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Affiliation(s)
- Judith A Beto
- Loyola University Healthcare System, Maywood, IL 60153, USA. ; Department of Nutrition Sciences, Dominican University, River Forest, IL 60305, USA
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22
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Pasiakos SM, Margolis LM, Orr JS. Optimized dietary strategies to protect skeletal muscle mass during periods of unavoidable energy deficit. FASEB J 2014; 29:1136-42. [DOI: 10.1096/fj.14-266890] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/01/2014] [Indexed: 12/14/2022]
Affiliation(s)
- Stefan M. Pasiakos
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Lee M. Margolis
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Jeb S. Orr
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
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23
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Hellhammer J, Vogt D, Franz N, Freitas U, Rutenberg D. A soy-based phosphatidylserine/ phosphatidic acid complex (PAS) normalizes the stress reactivity of hypothalamus-pituitary-adrenal-axis in chronically stressed male subjects: a randomized, placebo-controlled study. Lipids Health Dis 2014; 13:121. [PMID: 25081826 PMCID: PMC4237891 DOI: 10.1186/1476-511x-13-121] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 07/21/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Supplementation with a phosphatidylserine and phosphatidylserine/ phosphatidic acid complex (PAS) has been observed to normalize stress induced dysregulations of the hypothalamus-pituitary-adrenal axis (HPAA). Prolonged stress first induces a hyper-activation of the HPAA, which then can be followed by a state of hypo-activation.The aim of this study was to examine effects of an oral supplementation with 400 mg PS & 400 mg PA (PAS 400) per day on the endocrine stress response (ACTH, saliva and serum cortisol) to a psychosocial stressor. A special focus was to analyze subgroups of low versus high chronically stressed subjects as well as to test efficacy of 200 mg PS & 200 mg PA (PAS 200). METHODS 75 healthy male volunteers were enrolled for this double-blind, placebo-controlled study, stratified by chronic stress level, and randomly allocated to one of three study arms (placebo, PAS 200 and PAS 400 per day, respectively). Study supplementation was administered for 42 days for each participant. Chronic stress was measured with the Trier Inventory for Chronic Stress (TICS), and subgroups of high and low chronic stress were differentiated by median values as provided by the TICS authors. A six week period of supplementation was followed by an acute stress test (Trier Social Stress Test - TSST). RESULTS Chronic stress levels and other baseline measures did not differ between treatment groups (all p>0.05). Acute stress was successfully induced by the TSST and resulted in a hyper-responsivity of the HPAA in chronically stressed subjects. Compared to placebo, a supplementation with a daily dose of PAS 400 was effective in normalizing the ACTH (p=0.010), salivary (p=0.043) and serum cortisol responses (p=0.035) to the TSST in chronically high but not in low stressed subjects (all p>0.05). Compared to placebo, supplementation with PAS 200 did not result in any significant differences in these variables (all p>0.05). There were no significant effects of supplementation with PAS on heart rate, pulse transit time, or psychological stress response (all p>0.05). CONCLUSION In chronically stressed subjects, a supplementation with PAS 400 (MemreePlus™) can normalize the hyper-responsivity of the HPAA to an acute stressor. TRIAL REGISTRATION TRIAL REGISTRATION DRKS-ID: DRKS00005125.
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Affiliation(s)
- Juliane Hellhammer
- Diagnostic Assessment and Clinical Research Organization (Daacro) GmbH & Co. KG, Science Park Trier, Max-Planck-Str. 22, 54296 Trier, Germany
| | - Dominic Vogt
- Diagnostic Assessment and Clinical Research Organization (Daacro) GmbH & Co. KG, Science Park Trier, Max-Planck-Str. 22, 54296 Trier, Germany
| | - Nadin Franz
- Diagnostic Assessment and Clinical Research Organization (Daacro) GmbH & Co. KG, Science Park Trier, Max-Planck-Str. 22, 54296 Trier, Germany
| | - Ulla Freitas
- Lonza Ltd, Muenchensteinerstr. 38, 4002 Basel, Switzerland
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Pasiakos SM, Carbone JW. Assessment of skeletal muscle proteolysis and the regulatory response to nutrition and exercise. IUBMB Life 2014; 66:478-84. [PMID: 25052691 DOI: 10.1002/iub.1291] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/01/2014] [Indexed: 01/07/2023]
Abstract
Skeletal muscle proteolysis is highly regulated, involving complex intramuscular proteolytic systems that recognize and degrade muscle proteins, and recycle free amino acid precursors for protein synthesis and energy production. Autophagy-lysosomal, calpain, and caspase systems are contributors to muscle proteolysis, although the ubiquitin proteasome system (UPS) is the primary mechanism by which actomyosin fragments are degraded in healthy muscle. The UPS is sensitive to mechanical force and nutritional deprivation, as recent reports have demonstrated increased proteolytic gene expression and activity of the UPS in response to resistance and endurance exercise, and short-term negative energy balance. However, consuming dietary protein alone (or free amino acids), or as a primary component of a mixed meal, may attenuate intramuscular protein loss by down-regulating proteolytic gene expression and the catabolic activity of the UPS. Although these studies provide novel insight regarding the intramuscular regulation of skeletal muscle mass, the role of proteolysis in the regulation of skeletal muscle protein turnover in healthy human muscle is not well described. This article provides a contemporary review of the intramuscular regulation of skeletal muscle proteolysis in healthy muscle, methodological approaches to assess proteolysis, and highlights the effects of nutrition and exercise on skeletal muscle proteolysis.
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Affiliation(s)
- Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, Natick, MA, USA
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25
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Renoud A, Ecochard R, Marchand F, Chapurlat R, Szulc P. Predictive parameters of accelerated muscle loss in men-MINOS study. Am J Med 2014; 127:554-61. [PMID: 24524994 DOI: 10.1016/j.amjmed.2014.02.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/29/2014] [Accepted: 02/01/2014] [Indexed: 12/25/2022]
Abstract
BACKGROUND Aging-related muscle loss is a public health problem. We investigated the association of lifestyle and hormonal factors with a prospectively assessed muscle loss in older men. METHODS Among 608 home-dwelling men, aged 60-85 (mean 68) years, lifestyle and health status were evaluated through a questionnaire. Appendicular skeletal muscle mass was estimated using dual-energy x-ray absorptiometry and calculated as the sum of lean mass of the 4 limbs. Free testosterone concentration was calculated using concentrations of total testosterone and sex hormone-binding globulin. Longitudinal data were analyzed by hierarchical models. RESULTS Average muscle loss was 0.63 ± 0.05%/year. The results of our multivariable adjusted analyses showed that muscle loss was higher in men whose leisure physical activity was <15 hours/week versus ≥15 hours/week (-0.76 vs -0.57%/year). Age-related acceleration of muscle loss was greater in men with lower total testosterone levels (<10 vs ≥10 nmol/L: -0.10 vs -0.07%/year/year of age at baseline [age]). Men with lower free testosterone (<75 vs ≥75 pmol/L) had greater age-related acceleration of muscle loss (-0.12 vs -0.08%/year/age). Higher parathyroid hormone concentrations were associated with greater age-related acceleration of muscle loss (≥45 vs <45 pg/mL -0.14 vs -0.12%/year/age). Men with type 2 diabetes had higher age-related acceleration of muscle loss versus men without diabetes (-0.08 vs -0.03%/year/age) (All P values are <.05). CONCLUSION In elderly men, low leisure physical activity, type 2 diabetes, low total and free testosterone, and elevated parathyroid hormone concentrations are associated with greater age-related acceleration of muscle loss. These factors are likely to represent real determinants of aging-related muscle loss in men.
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Affiliation(s)
- Alexia Renoud
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unit 1033, University of Lyon, Lyon, France
| | - René Ecochard
- Department of Biostatistics, University of Lyon, UMR CNRS 5558, Lyon, France
| | | | - Roland Chapurlat
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unit 1033, University of Lyon, Lyon, France
| | - Pawel Szulc
- Institut National de la Santé et de la Recherche Médicale (INSERM) Unit 1033, University of Lyon, Lyon, France.
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26
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Abstract
Amino acid (AA) transporters may act as sensors, as well as carriers, of tissue nutrient supplies. This review considers recent advances in our understanding of the AA-sensing functions of AA transporters in both epithelial and nonepithelial cells. These transporters mediate AA exchanges between extracellular and intracellular fluid compartments, delivering substrates to intracellular AA sensors. AA transporters on endosomal (eg, lysosomal) membranes may themselves function as intracellular AA sensors. AA transporters at the cell surface, particularly those for large neutral AAs such as leucine, interact functionally with intracellular nutrient-signaling pathways that regulate metabolism: for example, the mammalian target of rapamycin complex 1 (mTORC1) pathway, which promotes cell growth, and the general control non-derepressible (GCN) pathway, which is activated by AA starvation. Under some circumstances, upregulation of AA transporter expression [notably a leucine transporter, solute carrier 7A5 (SLC7A5)] is required to initiate AA-dependent activation of the mTORC1 pathway. Certain AA transporters may have dual receptor-transporter functions, operating as "transceptors" to sense extracellular (or intracellular) AA availability upstream of intracellular signaling pathways. New opportunities for nutritional therapy may include targeting of AA transporters (or mechanisms that upregulate their expression) to promote protein-anabolic signals for retention or recovery of lean tissue mass.
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Affiliation(s)
- Peter M Taylor
- Division of Cell Signalling & Immunology, College of Life Sciences, University of Dundee, Dundee, United Kingdom
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27
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Abstract
Human skeletal muscles are continually remodeled to match the function required of them. Diameter, strength, and vascular supply are altered when a muscle group experiences contraction and resistance. The purpose of this article is to describe selected muscle signaling pathways that contribute to muscle remodeling. Multiple factors affect the cellular and molecular remodeling of muscles and at least 2 of them-exercise and protein/calorie delivery-are under the direct care of intensive care unit (ICU) clinicians. Activating signaling pathways may promote preservation of muscle mass and function. Interventions to prevent muscle atrophy have potential to reduce ICU-acquired weakness and positively affect quality of life in survivors after ICU hospitalization. Exploring information generated by genomic and proteomic investigations about muscle signaling pathways can help the ICU clinician evaluate the benefits and risks of interventions to maintain muscle health early in critical illness.
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28
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Pasiakos SM, McClung JP. miRNA analysis for the assessment of exercise and amino acid effects on human skeletal muscle. Adv Nutr 2013; 4:412-7. [PMID: 23858090 PMCID: PMC3941821 DOI: 10.3945/an.113.003699] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The study of micro RNA (miRNA) expression and function, a largely unexplored area of human muscle biology, may provide novel data regarding the development of targeted approaches that optimize skeletal muscle responses to exercise and amino acid manipulations. miRNAs are ubiquitously expressed, small noncoding RNAs that modulate posttranscriptional gene expression. Quantifying miRNA expression and predicting function as regulators of both single targets and complex networks is technically challenging and requires a combined approach of bioinformatics, molecular, and systems biology. Recent evidence suggests that the expression of muscle-specific miRNAs (myomirs), including miR-1, miR-133a/b, miR-206, and miR-499, is modulated by essential amino acid ingestion, endurance exercise, and endurance exercise training. The expression of miRNAs has also been implicated in the anabolic intracellular signaling and muscle hypertrophic response associated with resistance exercise training. Although these findings are intriguing, comprehensive human trials assessing functional outcomes associated with changes in miRNA expression in response to exercise and nutrition interventions have not been conducted. This article reviews the current understanding of miRNA biology and includes analytical techniques used to detect miRNA expression and methods to predict function. The intent is to provide the framework for future research studies that use miRNA analysis in an effort to elucidate optimal exercise and nutritional countermeasures for the prevention of muscle loss.
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Bonjour JP, Kraenzlin M, Levasseur R, Warren M, Whiting S. Dairy in adulthood: from foods to nutrient interactions on bone and skeletal muscle health. J Am Coll Nutr 2013; 32:251-63. [PMID: 24024770 PMCID: PMC3836362 DOI: 10.1080/07315724.2013.816604] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 05/27/2013] [Indexed: 12/02/2022]
Abstract
The risk of fragility fractures exponentially increases with aging. Reduced mass and strength of both bone in osteoporosis and skeletal muscle in sarcopenia play a key role in the age-related incidence of fragility fractures. Undernutrition is often observed in the elderly, particularly in those subjects experiencing osteoporotic fractures, more likely as a cause than a consequence. Calcium (Ca), inorganic phosphate (Pi), vitamin D, and protein are nutrients that impact bone and skeletal muscle integrity. Deficiency in the supply of these nutrients increases with aging. Dairy foods are rich in Ca, Pi, and proteins and in many countries are fortified with vitamin D. Dairy foods are important souces of these nutrients and go a long way to meeting the recommendations, which increase with aging. This review emphaszes the interactions between these 4 nutrients, which, along with physical activity, act through cellular and physiological pathways favoring the maintenance of both bone and skeletal muscle structure and function.
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Affiliation(s)
- Jean-Philippe Bonjour
- Division of Bone Disease, University Hospitals and Faculty of Medicine, Geneva, SWITZERLAND
| | - Marius Kraenzlin
- Division of Endocrinology, Diabetes and Metabolism, University Hospital, Bale, SWITZERLAND
| | | | - Michelle Warren
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York
| | - Susan Whiting
- College of Pharmacy and Nutrition, University of Saskatchewan, CANADA
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