1
|
Witard OC, Banic M, Rodriguez-Sanchez N, van Dijk M, Galloway SDR. Long-chain n-3 PUFA ingestion for the stimulation of muscle protein synthesis in healthy older adults. Proc Nutr Soc 2023:1-11. [PMID: 37987178 DOI: 10.1017/s0029665123004834] [Citation(s) in RCA: 1] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
This review aims to critically evaluate the efficacy of long-chain ո-3 PUFA ingestion in modulating muscle protein synthesis (MPS), with application to maintaining skeletal muscle mass, strength and function into later life. Ageing is associated with a gradual decline in muscle mass, specifically atrophy of type II fibres, that is exacerbated by periods of (in)voluntary muscle disuse. At the metabolic level, in otherwise healthy older adults, muscle atrophy is underpinned by anabolic resistance which describes the impaired MPS response to non-pharmacological anabolic stimuli, namely, physical activity/exercise and amino acid provision. Accumulating evidence implicates a mechanistic role for n-3 PUFA in upregulating MPS under stimulated conditions (post-prandial state or following exercise) via incorporation of EPA and DHA into the skeletal muscle phospholipid membrane. In some instances, these changes in MPS with chronic ո-3 PUFA ingestion have translated into clinically relevant improvements in muscle mass, strength and function; an observation evidently more prevalent in healthy older women than men. This apparent sexual dimorphism in the adaptive response of skeletal muscle metabolism to EPA and DHA ingestion may be related to a greater propensity for females to incorporate ո-3 PUFA into human tissue and/or the larger dose of ingested ո-3 PUFA when expressed relative to body mass or lean body mass. Future experimental studies are warranted to characterise the optimal dosing and duration of ո-3 PUFA ingestion to prescribe tailored recommendations regarding n-3 PUFA nutrition for healthy musculoskeletal ageing into later life.
Collapse
Affiliation(s)
- Oliver C Witard
- Centre for Human and Applied Physiological Sciences, King's College London, London, UK
| | - Milena Banic
- Physiology, Exercise and Nutrition Research Group, University of Stirling, Stirling, Scotland, UK
| | - Nidia Rodriguez-Sanchez
- Physiology, Exercise and Nutrition Research Group, University of Stirling, Stirling, Scotland, UK
| | | | - Stuart D R Galloway
- Physiology, Exercise and Nutrition Research Group, University of Stirling, Stirling, Scotland, UK
| |
Collapse
|
2
|
Borack MS, Dickinson JM, Fry CS, Reidy PT, Markofski MM, Deer RR, Jennings K, Volpi E, Rasmussen BB. Effect of the lysosomotropic agent chloroquine on mTORC1 activation and protein synthesis in human skeletal muscle. Nutr Metab (Lond) 2021; 18:61. [PMID: 34118944 PMCID: PMC8199655 DOI: 10.1186/s12986-021-00585-w] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 05/28/2021] [Indexed: 11/16/2022] Open
Abstract
Background Previous work in HEK-293 cells demonstrated the importance of amino acid-induced mTORC1 translocation to the lysosomal surface for stimulating mTORC1 kinase activity and protein synthesis. This study tested the conservation of this amino acid sensing mechanism in human skeletal muscle by treating subjects with chloroquine—a lysosomotropic agent that induces in vitro and in vivo lysosome dysfunction. Methods mTORC1 signaling and muscle protein synthesis (MPS) were determined in vivo in a randomized controlled trial of 14 subjects (10 M, 4 F; 26 ± 4 year) that ingested 10 g of essential amino acids (EAA) after receiving 750 mg of chloroquine (CHQ, n = 7) or serving as controls (CON, n = 7; no chloroquine). Additionally, differentiated C2C12 cells were used to assess mTORC1 signaling and myotube protein synthesis (MyPS) in the presence and absence of leucine and the lysosomotropic agent chloroquine. Results mTORC1, S6K1, 4E-BP1 and rpS6 phosphorylation increased in both CON and CHQ 1 h post EAA ingestion (P < 0.05). MPS increased similarly in both groups (CON, P = 0.06; CHQ, P < 0.05). In contrast, in C2C12 cells, 1 mM leucine increased mTORC1 and S6K1 phosphorylation (P < 0.05), which was inhibited by 2 mg/ml chloroquine. Chloroquine (2 mg/ml) was sufficient to disrupt mTORC1 signaling, and MyPS. Conclusions Chloroquine did not inhibit amino acid-induced activation of mTORC1 signaling and skeletal MPS in humans as it does in C2C12 muscle cells. Therefore, different in vivo experimental approaches are required for confirming the precise role of the lysosome and amino acid sensing in human skeletal muscle. Trial registration NCT00891696. Registered 29 April 2009.
Collapse
Affiliation(s)
- Michael S Borack
- Division of Rehabilitation Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Nutrition and Metabolism, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Center for the Study of Aging and Human Development, Duke University, Durham, NC, USA
| | - Jared M Dickinson
- Department of Nutrition and Metabolism, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Health Sciences, Central Washington University, Ellensburg, WA, USA
| | - Christopher S Fry
- Department of Nutrition and Metabolism, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY, USA
| | - Paul T Reidy
- Division of Rehabilitation Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Nutrition and Metabolism, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Kinesiology, Nutrition and Health, Miami of Ohio University, Oxford, OH, USA
| | - Melissa M Markofski
- Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Health and Human Performance, University of Houston, Houston, TX, USA
| | - Rachel R Deer
- Division of Rehabilitation Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA
| | - Kristofer Jennings
- Department of Preventive Medicine and Population Health, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Elena Volpi
- Department of Internal Medicine/Geriatrics, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.,Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA
| | - Blake B Rasmussen
- Department of Nutrition and Metabolism, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA. .,Sealy Center On Aging, University of Texas Medical Branch, 301 University Blvd, Galveston, TX, 77555-1124, USA.
| |
Collapse
|
3
|
Jespersen SE, Agergaard J. Evenness of dietary protein distribution is associated with higher muscle mass but not muscle strength or protein turnover in healthy adults: a systematic review. Eur J Nutr 2021; 60:3185-3202. [PMID: 33550490 DOI: 10.1007/s00394-021-02487-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [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: 03/31/2020] [Accepted: 01/08/2021] [Indexed: 02/06/2023]
Abstract
PURPOSE Age-related decrease in muscle mass is, among several other factors, caused by suboptimal dietary protein intake. The protein intake of the general population has a skewed distribution towards the evening meal. However, it is hypothesised that an intake of protein with an even meal distribution leads to a more frequently maximised protein synthesis. This review investigates whether an even protein distribution is associated with preservation or gain in muscle mass, muscle strength, and protein turnover. METHODS Seven databases: PubMed, Web of Science, Google Scholar, CINAHL, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Embase were searched. Studies included had a healthy population between 20 and 85 years of age, with a BMI between 18.5 and 30.0, investigated even vs. skewed protein distribution, and measured skeletal muscle relevant outcomes. Case studies and systematic reviews were excluded. Studies were appraised using the AXIS scale for observational studies and the PEDro scale for the remaining studies. RESULTS Fifteen studies met the eligibility criteria and were included. Three out of seven studies showed an association between even protein distribution and higher muscle mass. Two out of seven studies showed an association between greater muscle strength and an even protein distribution. Only one out of six studies found a positive association between protein synthesis and an even protein distribution. CONCLUSION Evidence indicated an association between muscle mass and an even protein intake. However, the evidence is currently insufficient to conclude whether an even protein intake is positively associated with muscle strength or protein turnover.
Collapse
Affiliation(s)
- Simon E Jespersen
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark and Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Agergaard
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark and Center for Healthy Aging, Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
4
|
Blears E, Ross E, Ogunbileje JO, Porter C, Murton AJ. The impact of catecholamines on skeletal muscle following massive burns: Friend or foe? Burns 2021; 47:756-764. [PMID: 33568281 DOI: 10.1016/j.burns.2021.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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: 10/26/2020] [Accepted: 01/20/2021] [Indexed: 02/07/2023]
Abstract
Profound skeletal muscle wasting in the setting of total body hypermetabolism is a defining characteristic of massive burns, compromising the patient's recovery and necessitating a protracted period of rehabilitation. In recent years, the prolonged use of the non-selective beta-blocker, propranolol, has gained prominence as an effective tool to assist with suppressing epinephrine-dependent burn-induced hypermetabolism and by extension, blunting muscle catabolism. However, synthetic β-adrenergic agonists, such as clenbuterol, are widely associated with the promotion of muscle growth in both animals and humans. Moreover, experimental adrenodemedullation is known to result in muscle catabolism. Therefore, the blunting of muscle β-adrenergic signaling via the use of propranolol would be expected to negatively impair muscle protein homeostasis. This review explores these paradoxical observations and identifies the manner by which propranolol is thought to exert its anti-catabolic effects in burn patients. Moreover, we identify potential avenues by which the use of beta-blocker therapy in the treatment of massive burns could potentially be further refined to promote the recovery of muscle mass in these critically ill patients while continuing to ameliorate total body hypermetabolism.
Collapse
Affiliation(s)
- Elizabeth Blears
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA; Department of Surgery, Allegheny Health Network, Pittsburgh, PA, USA
| | - Evan Ross
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA
| | - John O Ogunbileje
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA
| | - Craig Porter
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA; Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Andrew J Murton
- Department of Surgery, University of Texas Medical Branch, Galveston, TX, USA; Sealy Center of Aging, University of Texas Medical Branch, Galveston, TX, USA.
| |
Collapse
|
5
|
Parry SM, Puthucheary ZA. The impact of extended bed rest on the musculoskeletal system in the critical care environment. Extrem Physiol Med 2015; 4:16. [PMID: 26457181 PMCID: PMC4600281 DOI: 10.1186/s13728-015-0036-7] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 09/30/2015] [Indexed: 04/14/2023]
Abstract
Prolonged immobility is harmful with rapid reductions in muscle mass, bone mineral density and impairment in other body systems evident within the first week of bed rest which is further exacerbated in individuals with critical illness. Our understanding of the aetiology and secondary consequences of prolonged immobilization in the critically ill is improving with recent and ongoing research to establish the cause, effect, and best treatment options. This review aims to describe the current literature on bed rest models for examining immobilization-induced changes in the musculoskeletal system and pathophysiology of immobilisation in critical illness including examination of intracellular signalling processes involved. Finally, the review examines the current barriers to early activity and mobilization and potential rehabilitation strategies, which are being, investigated which may reverse the effects of prolonged bed rest. Addressing the deleterious effects of immobilization is a major step in treatment and prevention of the public health issue, that is, critical illness survivorship.
Collapse
Affiliation(s)
- Selina M. Parry
- />Department of Physiotherapy, School of Health Sciences, The University of Melbourne, Level 7 Alan Gilbert Building, Parkville, Melbourne, VIC 3010 Australia
| | - Zudin A. Puthucheary
- />Division of Respiratory and Critical Care Medicine, National University Health System, Singapore, Singapore
- />Institute of Health and Human Performance, University College London, London, UK
| |
Collapse
|
6
|
Murton AJ, Greenhaff PL. Resistance exercise and the mechanisms of muscle mass regulation in humans: acute effects on muscle protein turnover and the gaps in our understanding of chronic resistance exercise training adaptation. Int J Biochem Cell Biol 2013; 45:2209-14. [PMID: 23872221 DOI: 10.1016/j.biocel.2013.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [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: 03/20/2013] [Revised: 07/05/2013] [Accepted: 07/10/2013] [Indexed: 11/30/2022]
Abstract
Increasing muscle mass is important when attempting to maximize sports performance and achieve physique augmentation. However, the preservation of muscle mass is essential to maintaining mobility and quality of life with aging, and also impacts on our capacity to recover from illness. Nevertheless, our understanding of the processes that regulate muscle mass in humans during resistance exercise training, chronic disuse and rehabilitation training following atrophy remains very unclear. Here, we report on some of the recent developments in the study of those processes thought to be responsible for governing human muscle protein turnover in response to intense physical activity. Specifically, the effects of acute and chronic resistance exercise in healthy volunteers and also in response to rehabilitation resistance exercise training following muscle atrophy will be discussed, with discrepancies and gaps in our understanding highlighted. In particular, ubiquitin-proteasome mediated muscle proteolysis (Muscle Atrophy F-box/Atrogin-1 and Muscle RING Finger 1), translation initiation of muscle protein synthesis (mammalian target of rapamycin signaling), and satellite cell mediated myogenesis are highlighted as pathways of special relevance to muscle protein metabolism in response to acute resistance exercise. Furthermore, research focused on quantifying signaling and molecular events that modulate muscle protein synthesis and protein degradation under conditions of chronic resistance training is highlighted as being urgently needed to improve knowledge gaps. These studies need to include multiple time-point measurements over the course of any training intervention and must include dynamic measurements of muscle protein synthesis and degradation and sensitive measures of muscle mass. This article is part of a Directed Issue entitled Molecular basis of muscle wasting.
Collapse
Affiliation(s)
- A J Murton
- School of Biosciences, MRC/ARUK Centre for Musculoskeletal Ageing Research, University of Nottingham, Nottingham, UK
| | | |
Collapse
|