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de Marco Castro E, Valli G, Buffière C, Guillet C, Mullen B, Pratt J, Horner K, Naumann-Gola S, Bader-Mittermaier S, Paganini M, De Vito G, Roche HM, Dardevet D. Peripheral Amino Acid Appearance Is Lower Following Plant Protein Fibre Products, Compared to Whey Protein and Fibre Ingestion, in Healthy Older Adults despite Optimised Amino Acid Profile. Nutrients 2022; 15:nu15010035. [PMID: 36615694 PMCID: PMC9824653 DOI: 10.3390/nu15010035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
Plant-based proteins are generally characterised by lower Indispensable Amino Acid (IAA) content, digestibility, and anabolic properties, compared to animal-based proteins. However, they are environmentally friendlier, and wider consumption is advocated. Older adults have higher dietary protein needs to prevent sarcopenia, a disease marked by an accelerated loss of muscle mass and function. Given the lower environmental footprint of plant-based proteins and the importance of optimising dietary protein quality among older adults, this paper aims to assess the net peripheral Amino Acid (AA) appearance after ingestion of three different plant protein and fibre (PPF) products, compared to whey protein with added fibre (WPF), in healthy older adults. In a randomised, single-blind, crossover design, nine healthy men and women aged ≥65 years consumed four test meals balanced in AA according to the FAO reference protein for humans, matched for leucine, to optimally stimulate muscle protein synthesis in older adults. A fasted blood sample was drawn at each visit before consuming the test meal, followed by postprandial arterialise blood sampling every 30 min for 3 h. The test meal was composed of a soup containing either WPF or PPF 1-3. The PPF blends comprised pea proteins with varying additional rice, pumpkin, soy, oat, and/or almond protein. PPF product ingestion resulted in a lower maximal increase of postprandial leucine concentration and the sum of branched-chain AA (BCAA) and IAA concentrations, compared to WPF, with no effect on their incremental area under the curve. Plasma methionine and cysteine, and to a lesser extent threonine, appearance were limited after consuming the PPF products, but not WPF. Despite equal leucine doses, the WPF induced greater postprandial insulin concentrations than the PPF products. In conclusion, the postprandial appearance of AA is highly dependent on the protein source in older adults, despite providing equivalent IAA levels and dietary fibre. Coupled with lower insulin concentrations, this could imply less anabolic potential. Further investigation is required to understand the applicability of plant-based proteins in healthy older adults.
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Affiliation(s)
- Elena de Marco Castro
- UCD Conway Institute and UCD Institute of Food and Health, School of Public Health, Physiotherapy and Sports Science, University College Dublin, D04 V1W8 Dublin, Ireland
| | - Giacomo Valli
- Neuromuscular Physiology Laboratory, Department of Biomedical Science, University of Padua, 35122 Padova, Italy
| | - Caroline Buffière
- Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement, Rte de Theix, 63122 Saint-Genès-Champanelle, France
| | - Christelle Guillet
- Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement, Rte de Theix, 63122 Saint-Genès-Champanelle, France
| | - Brian Mullen
- UCD Conway Institute and UCD Institute of Food and Health, School of Public Health, Physiotherapy and Sports Science, University College Dublin, D04 V1W8 Dublin, Ireland
| | - Jedd Pratt
- Neuromuscular Physiology Laboratory, Department of Biomedical Science, University of Padua, 35122 Padova, Italy
| | - Katy Horner
- UCD Conway Institute and UCD Institute of Food and Health, School of Public Health, Physiotherapy and Sports Science, University College Dublin, D04 V1W8 Dublin, Ireland
| | - Susanne Naumann-Gola
- Fraunhofer Institute for Process Engineering and Packaging IVV, Giggenhauser Str., 85354 Freising, Germany
| | | | - Matteo Paganini
- Neuromuscular Physiology Laboratory, Department of Biomedical Science, University of Padua, 35122 Padova, Italy
| | - Giuseppe De Vito
- Neuromuscular Physiology Laboratory, Department of Biomedical Science, University of Padua, 35122 Padova, Italy
| | - Helen M. Roche
- UCD Conway Institute and UCD Institute of Food and Health, School of Public Health, Physiotherapy and Sports Science, University College Dublin, D04 V1W8 Dublin, Ireland
- School of Biological Sciences, The Institute for Global Food Security, Queen’s University Belfast, Belfast BT7 1NN, UK
| | - Dominique Dardevet
- Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement, Rte de Theix, 63122 Saint-Genès-Champanelle, France
- Correspondence:
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Effect of the Use of a Cream with Leucine and Lactic Acid Associated with Electrostimulation in Contouring and Facial Tonus: A Randomized Clinical Controlled Trial. COSMETICS 2022. [DOI: 10.3390/cosmetics9020036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Evidence has supported the use of leucine as a promising agent for the maintenance of muscle tone. This study aimed to assess the combined effect of leucine and cream-based lactic acid (novel cosmetic product), associated with the use of surface electrical stimulation to improve contour and facial tonus in women. A total of 23 women were randomly allocated into two groups: Experimental (EG)—use of the leucine-based cream and lactic acid + electrostimulation for facial toning (mean intensity 13 Hz and protocol in progression); and placebo (GP)—use of the placebo cream (without the addition of leucine and lactic acid) + stimulation with the same protocol as the EG. Each group used their cream daily and underwent the intervention protocol three x/week with stimulation for 40 min, for a total of 8 weeks. Three main outcomes were reported: angular variation of facial contour by means of photogrammetry, muscle tone through the electromyographic activity of the masseter and zygomatic muscles during rest and functional tasks of biting and smiling. A significant effect of the intervention and between the groups was obtained for the experimental group against the placebo group for facial contour and muscle tone. An increased muscular activity of the masseter (average 28%) when smiling, and a reduction of zygomatic activity (in average 41%) when biting were found. The use of cream containing leucine and lactic acid combined with electrostimulation contributes to the improvement of facial contour and muscle tone when biting and smiling.
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Noncoding RNAs-associated ceRNA networks involved in the amelioration of skeletal muscle aging after whey protein supplementation. J Nutr Biochem 2022; 104:108968. [DOI: 10.1016/j.jnutbio.2022.108968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 01/06/2022] [Accepted: 01/19/2022] [Indexed: 11/23/2022]
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Important determinants to take into account to optimize protein nutrition in the elderly: solutions to a complex equation. Proc Nutr Soc 2020; 80:207-220. [PMID: 33198824 DOI: 10.1017/s0029665120007934] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
During ageing, skeletal muscle develops anabolic resistance towards the stimulation of protein synthesis induced by dietary amino acids. The stimulation of muscle protein synthesis after food intake remains insufficient, even with a protein intake recommended for healthy adults. This alteration is one of the mechanisms known to be responsible for the decrease of muscle mass and function during ageing, namely sarcopenia. Increasing dietary protein intake above the current RDA(0⋅83 g/kg/d) has been strongly suggested to overcome the anabolic resistance observed. It is also specified that the dietary protein ingested should be of good quality. A protein of good quality is a protein whose amino acid (AA) composition covers the requirement of each AA when ingested at the RDA. However, the biological value of proteins may vary among dietary sources in which AA composition could be unbalanced. In the present review, we suggest that the quality of a dietary protein is also related to several other determinants. These determinants include the speed of digestion of dietary proteins, the presence of specific AA, the food matrix in which the dietary proteins are included, the processes involved in the production of food products (milk gelation and cooking temperature), the energy supply and its nature, and the interaction between nutrients before ingestion. Particular attention is given to plant proteins for nutrition of the elderly. Finally, the timing of protein intake and its association with the desynchronized intake of energetic nutrients are discussed.
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Mirzoev TM. Skeletal Muscle Recovery from Disuse Atrophy: Protein Turnover Signaling and Strategies for Accelerating Muscle Regrowth. Int J Mol Sci 2020; 21:ijms21217940. [PMID: 33114683 PMCID: PMC7663166 DOI: 10.3390/ijms21217940] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/08/2020] [Accepted: 10/23/2020] [Indexed: 12/15/2022] Open
Abstract
Skeletal muscle fibers have a unique capacity to adjust their metabolism and phenotype in response to alternations in mechanical loading. Indeed, chronic mechanical loading leads to an increase in skeletal muscle mass, while prolonged mechanical unloading results in a significant decrease in muscle mass (muscle atrophy). The maintenance of skeletal muscle mass is dependent on the balance between rates of muscle protein synthesis and breakdown. While molecular mechanisms regulating protein synthesis during mechanical unloading have been relatively well studied, signaling events implicated in protein turnover during skeletal muscle recovery from unloading are poorly defined. A better understanding of the molecular events that underpin muscle mass recovery following disuse-induced atrophy is of significant importance for both clinical and space medicine. This review focuses on the molecular mechanisms that may be involved in the activation of protein synthesis and subsequent restoration of muscle mass after a period of mechanical unloading. In addition, the efficiency of strategies proposed to improve muscle protein gain during recovery is also discussed.
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Affiliation(s)
- Timur M Mirzoev
- Myology Laboratory, Institute of Biomedical Problems RAS, Moscow 123007, Russia
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Whey for Sarcopenia; Can Whey Peptides, Hydrolysates or Proteins Play a Beneficial Role? Foods 2020; 9:foods9060750. [PMID: 32517136 PMCID: PMC7353484 DOI: 10.3390/foods9060750] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 12/20/2022] Open
Abstract
As the human body ages, skeletal muscle loses its mass and strength. It is estimated that in 10% of individuals over the age of 60, this muscle frailty has progressed to sarcopenia. Biomarkers of sarcopenia include increases in inflammatory markers and oxidative stress markers and decreases in muscle anabolic markers. Whey is a high-quality, easily digested dairy protein which is widely used in the sports industry. This review explores the evidence that whey protein, hydrolysates or peptides may have beneficial effects on sarcopenic biomarkers in myoblast cell lines, in aged rodents and in human dietary intervention trials with the older consumer. A daily dietary supplementation of 35 g of whey is likely to improve sarcopenic biomarkers in frail or sarcopenia individuals. Whey supplementation, consumed by an older, healthy adult certainly improves muscle mTOR signaling, but exercise appears to have the greatest benefit to older muscle. In vitro cellular assays are central for bioactive and bioavailable peptide identification and to determine their mechanism of action on ageing muscle.
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Hanson ED, Betik AC, Timpani CA, Tarle J, Zhang X, Hayes A. Testosterone suppression does not exacerbate disuse atrophy and impairs muscle recovery that is not rescued by high protein. J Appl Physiol (1985) 2020; 129:5-16. [PMID: 32463734 DOI: 10.1152/japplphysiol.00752.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Androgen deprivation therapy (ADT) decreases muscle mass, force, and physical activity levels, but it is unclear whether disuse atrophy and testosterone suppression are additive. Additionally, conflicting reports exist on load-mediated hypertrophy during ADT and if protein supplementation offsets these deficits. This study sought to determine the role of testosterone suppression and a high-protein diet on 1) immobilization-induced atrophy and 2) muscle regrowth during reloading. Eight-week-old male Fischer 344 rats underwent sham surgery (Sham), castration surgery (ORX), or ORX and a high-casein diet supplemented with branched-chain amino acids (BCAA) (ORX+CAS/AA) followed by 10 days of unilateral immobilization (IMM) and 0, 6, or 14 days of reloading. With IMM, body mass gains were ~8% greater than ORX and ORX+CAS/AA that increased to 15% during reloading (both P < 0.01). IMM reduced muscle mass by 11-34% (all P < 0.01) and extensor digitorum longus and soleus (SOL) force by 21% and 49% (both P < 0.01), respectively, with no group differences. During reloading, castration reduced gastrocnemius mass (~12%) at 6 days and SOL mass (~20%) and SOL force recovery (~46%) at 14 days relative to Sham (all P < 0.05). Specific force reduced castration deficits, indicating that muscle atrophy was a key contributor. IMM decreased SOL cross-sectional area by 30.3% (P < 0.001), with a trend for reduced regrowth in ORX and ORX+CAS/AA following reloading (P = 0.083). Castration did not exacerbate disuse atrophy but may impair recovery of muscle function, with no benefit from a CAS/AA diet during reloading. Examining functional outcomes in addition to muscle mass during dietary interventions provides novel insights into muscle regrowth during ADT.NEW & NOTEWORTHY Low testosterone levels during skeletal muscle disuse did not worsen declines in muscle mass and function, although hypogonadism may attenuate recovery during subsequent reloading. Diets high in casein did not improve outcomes during immobilization or reloading. Practical strategies are needed that do not compromise caloric intake yet provide effective protein doses to augment these adverse effects.
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Affiliation(s)
- Erik D Hanson
- Department of Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina.,Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Andrew C Betik
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia.,Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - Cara A Timpani
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia.,Institute for Musculoskeletal Science (AIMSS), Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Victoria, Australia
| | - John Tarle
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Xinmei Zhang
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Alan Hayes
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia.,Institute for Musculoskeletal Science (AIMSS), Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Victoria, Australia
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Mariotti F, Gardner CD. Dietary Protein and Amino Acids in Vegetarian Diets-A Review. Nutrients 2019; 11:nu11112661. [PMID: 31690027 PMCID: PMC6893534 DOI: 10.3390/nu11112661] [Citation(s) in RCA: 155] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 10/26/2019] [Accepted: 10/31/2019] [Indexed: 12/13/2022] Open
Abstract
While animal products are rich in protein, the adequacy of dietary protein intake from vegetarian/vegan diets has long been controversial. In this review, we examine the protein and amino acid intakes from vegetarian diets followed by adults in western countries and gather information in terms of adequacy for protein and amino acids requirements, using indirect and direct data to estimate nutritional status. We point out that protein-rich foods, such as traditional legumes, nuts and seeds, are sufficient to achieve full protein adequacy in adults consuming vegetarian/vegan diets, while the question of any amino acid deficiency has been substantially overstated. Our review addresses the adequacy in changes to protein patterns in people newly transitioning to vegetarian diets. We also specifically address this in older adults, where the issues linked to the protein adequacy of vegetarian diets are more complex. This contrasts with the situation in children where there are no specific concerns regarding protein adequacy because of their very high energy requirements compared to those of protein. Given the growing shifts in recommendations from nutrition health professionals for people to transition to more plant-based, whole-food diets, additional scientific evidence-based communications confirming the protein adequacy of vegetarian and vegan diets is warranted.
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Affiliation(s)
- François Mariotti
- UMR PNCA, AgroParisTech, INRA, Université Paris-Saclay, 75005 Paris, France.
| | - Christopher D Gardner
- Department of Medicine, Stanford Prevention Research Center, Stanford University Medical School, Stanford, CA 94305, USA.
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Fujitani M, Mizushige T, Kawabata F, Uozumi K, Yasui M, Hayamizu K, Uchida K, Okada S, Keshab B, Kishida T. Dietary Alaska pollack protein improves skeletal muscle weight recovery after immobilization-induced atrophy in rats. PLoS One 2019; 14:e0217917. [PMID: 31199814 PMCID: PMC6570023 DOI: 10.1371/journal.pone.0217917] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/21/2019] [Indexed: 11/26/2022] Open
Abstract
The promotion of muscle recovery after immobilization is important to preserve an optimum health status. Here, we examined the effect of dietary Alaska pollack protein (APP) on skeletal muscle weight after atrophy induced by hind limb immobilization using plaster immobilization technique. Rat left limb was casted with a wetted plaster cast under anesthesia. After 2 weeks of feeding, the cast was removed and the rats were divided into three groups, namely, a baseline group, high-fat casein diet group, and high-fat APP diet group. After 3 weeks of feeding, the skeletal muscles (soleus, extensor digitorum longus [EDL], and gastrocnemius) were sampled. The estimated weight gains of soleus, gastrocnemius, and EDL muscle in the immobilized limbs were significantly larger in the rats fed with APP diet as compared with those fed with casein diet. In soleus muscle, dietary APP increased the expression of Igf1 and Myog genes in the immobilized limbs after the recovery period.
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Affiliation(s)
- Mina Fujitani
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
| | - Takafumi Mizushige
- Department of Applied Biological Chemistry, Faculty of Agriculture, Utsunomiya University, Minemachi, Utsunomiya, Tochigi, Japan
| | - Fuminori Kawabata
- Physiology of Domestic Animals, Faculty of Agriculture and Life Science, Hirosaki University, Bunkyo-cho, Hirosaki, Aomori, Japan
| | - Keisuke Uozumi
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
| | - Machi Yasui
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
| | - Kohsuke Hayamizu
- Laboratory of Food Chemistry, Yokohama University of Pharmacy, Yokohama, Japan
| | - Kenji Uchida
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
- Food Function R&D Center, Nippon Suisan Kaisha, Ltd., Tokyo, Japan
| | - Shinji Okada
- Graduate School of Agricultural and Life Sciences, the University of Tokyo, Tokyo, Japan
| | - Bhattarai Keshab
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
| | - Taro Kishida
- Laboratory of Nutrition Science, Division of Applied bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
- Food and Health Sciences Research Centre, Graduate School of Agriculture, Ehime University, Matsuyama, Japan
- * E-mail:
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Jarzaguet M, Polakof S, David J, Migné C, Joubrel G, Efstathiou T, Rémond D, Mosoni L, Dardevet D. A meal with mixed soy/whey proteins is as efficient as a whey meal in counteracting the age-related muscle anabolic resistance only if the protein content and leucine levels are increased. Food Funct 2019; 9:6526-6534. [PMID: 30475369 DOI: 10.1039/c8fo01903g] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
With aging, skeletal muscle becomes resistant to the anabolic effect of dietary proteins and sarcopenia develops. Animal proteins, which are rich in leucine, are recommended for the elderly, but it is not known whether their replacement by plant proteins would maintain the health and physical independence of this population. Aged rats were fed with animal proteins (casein and whey proteins) with different leucine contents and compared to rats fed with diets in which whey was substituted with soy proteins and by increasing the total protein content or not. Our results clearly showed that the meal with mixed soy/whey proteins allowed the anabolic response of skeletal muscle during aging only if the protein content was increased by 25%. Indeed, if the protein content of the soy/whey diet was decreased to a similar protein content such as a whey diet, i.e. 13%, the anabolic effect decreased. The same observation was recorded if the whey proteins were totally substituted with soy proteins.
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Affiliation(s)
- Marianne Jarzaguet
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, F-63000 Clermont-Ferrand, France.
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Mosoni L, Jarzaguet M, David J, Polakof S, Savary-Auzeloux I, Rémond D, Dardevet D. Post Meal Energy Boluses Do Not Increase the Duration of Muscle Protein Synthesis Stimulation in Two Anabolic Resistant Situations. Nutrients 2019; 11:E727. [PMID: 30934871 PMCID: PMC6520703 DOI: 10.3390/nu11040727] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/11/2019] [Accepted: 03/27/2019] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND When given in the long term, whey proteins alone do not appear to be an optimal nutritional strategy to prevent or slow down muscle wasting during aging or catabolic states. It has been hypothesized that the digestion of whey may be too rapid during a catabolic situation to sustain the anabolic postprandial amino acid requirement necessary to elicit an optimal anabolic response. Interestingly, it has been shown recently that the duration of the postprandial stimulation of muscle protein synthesis in healthy conditions can be prolonged by the supplementary ingestion of a desynchronized carbohydrate load after food intake. We verified this hypothesis in the present study in two different cases of muscle wasting associated with anabolic resistance, i.e., glucocorticoid treatment and aging. METHODS Multi-catheterized minipigs were treated or not with glucocorticoids for 8 days. Muscle protein synthesis was measured sequentially over time after the infusion of a 13C phenylalanine tracer using the arterio-venous method before and after whey protein meal ingestion. The energy bolus was given 150 min after the meal. For the aging study, aged rats were fed the whey meal and muscle protein synthesis was measured sequentially over time with the flooding dose method using 13C Valine. The energy bolus was given 210 min after the meal. RESULTS Glucocorticoid treatment resulted in a decrease in the duration of the stimulation of muscle protein synthesis. The energy bolus given after food intake was unable to prolong this stimulation despite a simultaneous increase of insulin and glucose following its absorption. In old rats, a similar observation was made with no effect of the energy bolus on the duration of the muscle anabolic response following whey protein meal intake. CONCLUSIONS Despite very promising observations in healthy situations, the strategy aimed at increasing muscle protein synthesis stimulation by giving an energy bolus during the postprandial period remained inefficient in our two anabolic resistance models.
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Affiliation(s)
- Laurent Mosoni
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Marianne Jarzaguet
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Jérémie David
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Sergio Polakof
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Isabelle Savary-Auzeloux
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Didier Rémond
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
| | - Dominique Dardevet
- Unité de Nutrition Humaine, INRA, Université Clermont Auvergne, UMR1019, F-63000 Clermont-Ferrand, France.
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Dijk FJ, van Dijk M, Walrand S, van Loon LJC, van Norren K, Luiking YC. Differential effects of leucine and leucine-enriched whey protein on skeletal muscle protein synthesis in aged mice. Clin Nutr ESPEN 2018; 24:127-133. [PMID: 29576350 DOI: 10.1016/j.clnesp.2017.12.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 12/29/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND & AIMS It has been suggested that anabolic resistance, or a blunted protein synthetic response to anabolic stimuli, contributes to the failure of muscle mass maintenance in older adults. The amino acid leucine is one of the most prominent food-related anabolic stimuli. However, data on muscle protein synthesis (MPS) after administration of a single bolus of leucine in aged populations is lacking and long-term single leucine supplementation has not been shown to increase muscle mass. This study aimed to determine the MPS response to the administration of a single bolus of leucine or to leucine combined with whey protein, in aged mice. METHODS Overnight fasted C57/BL6RJ mice at 25-mo of age received an oral gavage with leucine or whey-protein enriched with leucine (0.75 g/kg bodyweight total leucine in both) or 0.5 mL water (fasted control). Subsequently, mice were s.c. injected with puromycin (0.04 μmol/g bw at t = 30, 45 or 60 min) and were sacrificed 30 min thereafter. Amino acid concentrations were determined in plasma and right muscle tibialis anterior (TA). Left TA was used to analyse MPS by SUnSET method and phosphorylation rate of Akt, 4E-BP1 and p70S6k by western blot. RESULTS In aged mice, leucine administration failed to increase MPS, despite a 6-fold increase in plasma leucine and elevated muscle free leucine levels (P < 0.05). In contrast, leucine-enriched whey protein significantly stimulated MPS in aged mice at 60 min after gavage (P < 0.05). Muscle free EAA, NEAA and the phosphorylation rate of Akt, 4E-BP1 and p70S6k increased significantly (P < 0.05), only after administration of leucine-enriched whey protein. CONCLUSIONS MPS is stimulated in aged mice by leucine-enriched whey protein but not by leucine administration only. Administration of other amino acids may be required for leucine administration to stimulate muscle protein synthesis in aged mice.
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Affiliation(s)
- Francina J Dijk
- Nutricia Research, Nutricia Advanced Medical Nutrition, Utrecht, The Netherlands.
| | - Miriam van Dijk
- Nutricia Research, Nutricia Advanced Medical Nutrition, Utrecht, The Netherlands.
| | - Stéphane Walrand
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-630000 Clermont-Ferrand, France.
| | - Luc J C van Loon
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, The Netherlands.
| | | | - Yvette C Luiking
- Nutricia Research, Nutricia Advanced Medical Nutrition, Utrecht, The Netherlands; Texas A&M University, Department of Health and Kinesiology, Center for Translation Research in Aging & Longevity, College Station, United States.
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Koike TE, Watanabe AY, Kodama FY, Ozaki GAT, Castoldi RC, Garcia TA, Camargo RCT, Camargo Filho JCS. PHYSICAL EXERCISE AFTER IMMOBILIZATION OF SKELETAL MUSCLE OF ADULT AND AGED RATS. REV BRAS MED ESPORTE 2018. [DOI: 10.1590/1517-869220182401172423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
ABSTRACT Introduction: Immobilization is a treatment technique often used to reduce pain and prevent worsening of the injury. However, it promotes harmful effects on musculoskeletal tissue, resulting in a marked loss of muscle function, which may be aggravated in the elderly. Physical exercise is an important intervention to mitigate these harmful effects. Objective: To analyze possible morphometric changes in the gastrocnemius muscle of rats after immobilization and remobilization with physical exercise. Methods: Fifty-six rats were divided into adult (A) and aged (E) groups and subdivided into adult and aged control (AC and EC), immobilized (AI and EI), free remobilized (AIF and EIF), and remobilized through physical exercise (AIE and EIE). The hind limbs were immobilized with the gastrocnemius muscle in a shortened position for a period of seven days, except for the control group. The exercise protocol consisted of five swimming sessions, once per day (25 minutes/session). The animals were euthanized by administration of an overdose of ketamine hydrochloride plus xylazine hydrochloride, followed by sample collection and preparation of hematoxylin and eosin slides. Measurements of the smallest diameter of 120 muscle fibers of each animal were taken with software NIS-Elements D3.0 - SP7 - Nikon® instruments Inc., NY, USA. Results: There was a significant reduction in the mean fiber diameter in the AI (38.43 µm ± 4.20; p=0.01) and AIF (36.97 µm ± 3.41; p<0.01) groups compared to AC (45.39 µm ± 3.41) and in the EI (42.26 µm ± 4.39; p<0.01), EIF (36.00 µm ± 4.15; p<0.01), and EIE (41.86 µm ± 4.95; p<0.01) groups compared to the EC (51.37 µm ± 3.86) group. The data showed that exercise was able to restore muscle trophism in the adult groups; however, none of the protocols has succeeded in aged rats. Conclusion: Immobilization in the shortened position induced muscle atrophy and physical exercise was effective in restoring muscular trophism only in adult animals. Level of Evidence I; Therapeutic studies - Investigating the Results of Treatment.
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Affiliation(s)
- Tatiana Emy Koike
- Universidade Estadual de São Paulo “Julio de Mesquita Filho”, Brazil
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Revel A, Jarzaguet M, Peyron MA, Papet I, Hafnaoui N, Migné C, Mosoni L, Polakof S, Savary-Auzeloux I, Rémond D, Dardevet D. At same leucine intake, a whey/plant protein blend is not as effective as whey to initiate a transient post prandial muscle anabolic response during a catabolic state in mini pigs. PLoS One 2017; 12:e0186204. [PMID: 29045496 PMCID: PMC5646799 DOI: 10.1371/journal.pone.0186204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 09/27/2017] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Muscle atrophy has been explained by an anabolic resistance following food intake and an increase of dietary protein intake is recommended. To be optimal, a dietary protein has to be effective not only to initiate but also to prolong a muscle anabolic response in a catabolic state. To our knowledge, whether or not a dairy or a dairy/plant protein blend fulfills these criterions is unknown in a muscle wasting situation. OBJECTIVE Our aim was, in a control and a catabolic state, to measure continuously muscle anabolism in term of intensity and duration in response to a meal containing casein (CAS), whey (WHEY) or a whey/ plant protein blend (BLEND) and to evaluate the best protein source to elicit the best post prandial anabolism according to the physio-pathological state. METHODS Adult male Yucatan mini pigs were infused with U-13C-Phenylalanine and fed either CAS, WHEY or BLEND. A catabolic state was induced by a glucocorticoid treatment for 8 days (DEX). Muscle protein synthesis, proteolysis and balance were measured with the hind limb arterio-venous differences technique. Repeated time variance analysis were used to assess significant differences. RESULTS In a catabolic situation, whey proteins were able to initiate muscle anabolism which remained transient in contrast to the stimulated muscle protein accretion with WHEY, CAS or BLEND in healthy conditions. Despite the same leucine intake compared to WHEY, BLEND did not restore a positive protein balance in DEX animals. CONCLUSIONS Even with WHEY, the duration of the anabolic response was not optimal and has to be improved in a catabolic state. The use of BLEND remained of lower efficiency even at same leucine intake than whey.
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Affiliation(s)
- Aurélia Revel
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Marianne Jarzaguet
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Marie-Agnès Peyron
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Isabelle Papet
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Noureddine Hafnaoui
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Carole Migné
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Laurent Mosoni
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Sergio Polakof
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Isabelle Savary-Auzeloux
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Didier Rémond
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
| | - Dominique Dardevet
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, PFEM, MetaboHUB-Clermont, CRNH Auvergne, Clermont-Ferrand, France
- * E-mail:
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Verney J, Martin V, Ratel S, Chavanelle V, Bargetto M, Etienne M, Chaplais E, Le Ruyet P, Bonhomme C, Combaret L, Guillet C, Boisseau N, Sirvent P, Dardevet D. Soluble Milk Proteins Improve Muscle Mass Recovery after Immobilization-Induced Muscle Atrophy in Old Rats but Do not Improve Muscle Functional Property Restoration. J Nutr Health Aging 2017; 21:1133-1141. [PMID: 29188872 DOI: 10.1007/s12603-016-0855-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES Effect of 3 different dairy protein sources on the recovery of muscle function after limb immobilization in old rats. DESIGN Longitudinal animal study. SETTING Institut National de la Recherche Agronomique (INRA). The study took part in a laboratory setting. INTERVENTION Old rats were subjected to unilateral hindlimb immobilization for 8 days and then allowed to recover with 3 different dietary proteins: casein, soluble milk proteins or whey proteins for 49 days. MEASUREMENTS Body weight, muscle mass, muscle fibre size, isometric, isokinetic torque, muscle fatigability and muscle oxidative status were measured before and at the end of the immobilization period and during the recovery period i.e 7, 21, 35 and 49 days post immobilization. RESULTS In contrast to the casein diet, soluble milk proteins and whey proteins were efficient to favor muscle mass recovery after cast immobilization during aging. By contrast, none of the 3 diary proteins was able to improve muscle strength, power and fatigability showing a discrepancy between the recovery of muscle mass and function. However, the soluble milk proteins allowed a better oxidative capacity in skeletal muscle during the rehabilitation period. CONCLUSION Whey proteins and soluble milk proteins improve muscle mass recovery after immobilization-induced muscle atrophy in old rats but do not allow muscle functional property restoration.
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Affiliation(s)
- J Verney
- Dominique Dardevet, INRA, Unité de Nutrition Humaine (UNH, UMR 1019), CRNH Auvergne, France,
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Age-related deficits in skeletal muscle recovery following disuse are associated with neuromuscular junction instability and ER stress, not impaired protein synthesis. Aging (Albany NY) 2016; 8:127-46. [PMID: 26826670 PMCID: PMC4761718 DOI: 10.18632/aging.100879] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Age-related loss of muscle mass and strength can be accelerated by impaired recovery of muscle mass following a transient atrophic stimulus. The aim of this study was to identify the mechanisms underlying the attenuated recovery of muscle mass and strength in old rats following disuse-induced atrophy. Adult (9 month) and old (29 month) male F344BN rats underwent hindlimb unloading (HU) followed by reloading. HU induced significant atrophy of the hindlimb muscles in both adult (17-38%) and old (8-29%) rats, but only the adult rats exhibited full recovery of muscle mass and strength upon reloading. Upon reloading, total RNA and protein synthesis increased to a similar extent in adult and old muscles. At baseline and upon reloading, however, proteasome-mediated degradation was suppressed leading to an accumulation of ubiquitin-tagged proteins and p62. Further, ER stress, as measured by CHOP expression, was elevated at baseline and upon reloading in old rats. Analysis of mRNA expression revealed increases in HDAC4, Runx1, myogenin, Gadd45a, and the AChRs in old rats, suggesting neuromuscular junction instability/denervation. Collectively, our data suggests that with aging, impaired neuromuscular transmission and deficits in the proteostasis network contribute to defects in muscle fiber remodeling and functional recovery of muscle mass and strength.
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Dideriksen K, Boesen A, Kristiansen J, Magnusson S, Schjerling P, Holm L, Kjaer M. Skeletal muscle adaptation to immobilization and subsequent retraining in elderly men: No effect of anti-inflammatory medication. Exp Gerontol 2016; 82:8-18. [DOI: 10.1016/j.exger.2016.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 05/13/2016] [Accepted: 05/23/2016] [Indexed: 12/25/2022]
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Mobley CB, Fox CD, Thompson RM, Healy JC, Santucci V, Kephart WC, McCloskey AE, Kim M, Pascoe DD, Martin JS, Moon JR, Young KC, Roberts MD. Comparative effects of whey protein versus L-leucine on skeletal muscle protein synthesis and markers of ribosome biogenesis following resistance exercise. Amino Acids 2015; 48:733-750. [PMID: 26507545 DOI: 10.1007/s00726-015-2121-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 10/16/2015] [Indexed: 12/15/2022]
Abstract
We compared immediate post-exercise whey protein (WP, 500 mg) versus L-leucine (LEU, 54 mg) feedings on skeletal muscle protein synthesis (MPS) mechanisms and ribosome biogenesis markers 3 h following unilateral plantarflexor resistance exercise in male, Wistar rats (~250 g). Additionally, in vitro experiments were performed on differentiated C2C12 myotubes to compare nutrient (i.e., WP, LEU) and 'exercise-like' treatments (i.e., caffeine, hydrogen peroxide, and AICAR) on ribosome biogenesis markers. LEU and WP significantly increased phosphorylated-rpS6 (Ser235/236) in the exercised (EX) leg 2.4-fold (P < 0.01) and 2.7-fold (P < 0.001) compared to the non-EX leg, respectively, whereas vehicle-fed control (CTL) did not (+65 %, P > 0.05). Compared to the non-EX leg, MPS levels increased 32 % and 52 % in the EX leg of CTL (P < 0.01) and WP rats (P < 0.001), respectively, but not in LEU rats (+15 %, P > 0.05). Several genes associated with ribosome biogenesis robustly increased in the EX versus non-EX legs of all treatments; specifically, c-Myc mRNA, Nop56 mRNA, Bop1 mRNA, Ncl mRNA, Npm1 mRNA, Fb1 mRNA, and Xpo-5 mRNA. However, only LEU significantly increased 45S pre-rRNA levels in the EX leg (63 %, P < 0.001). In vitro findings confirmed that 'exercise-like' treatments similarly altered markers of ribosome biogenesis, but only LEU increased 47S pre-rRNA levels (P < 0.01). Collectively, our data suggests that resistance exercise, as well as 'exercise-like' signals in vitro, acutely increase the expression of genes associated with ribosome biogenesis independent of nutrient provision. Moreover, while EX with or without WP appears superior for enhancing translational efficiency (i.e., increasing MPS per unit of RNA), LEU administration (or co-administration) may further enhance ribosome biogenesis over prolonged periods with resistance exercise.
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Affiliation(s)
- C Brooks Mobley
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Carlton D Fox
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Richard M Thompson
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - James C Healy
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Vincent Santucci
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Wesley C Kephart
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Anna E McCloskey
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA
| | - Mike Kim
- MusclePharm Sports Science Institute, Denver, CO, USA
| | - David D Pascoe
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA.,Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine-Auburn Campus, Auburn, AL, USA
| | - Jeffrey S Martin
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA.,Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine-Auburn Campus, Auburn, AL, USA
| | - Jordan R Moon
- MusclePharm Sports Science Institute, Denver, CO, USA
| | | | - Michael D Roberts
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, 301 Wire Road, Office 286, Auburn, AL, 36849, USA. .,Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine-Auburn Campus, Auburn, AL, USA.
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Milan AM, D'Souza RF, Pundir S, Pileggi CA, Thorstensen EB, Barnett MPG, Markworth JF, Cameron-Smith D, Mitchell CJ. Older Adults Have Delayed Amino Acid Absorption after a High Protein Mixed Breakfast Meal. J Nutr Health Aging 2015; 19:839-45. [PMID: 26412288 DOI: 10.1007/s12603-015-0500-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVES To measure the postprandial plasma amino acid appearance in younger and older adults following a high protein mixed meal. DESIGN Cross-sectional study. SETTING Clinical research setting. PARTICIPANTS Healthy men and women aged 60-75 (n=15) years, and young controls aged 20-25 years (n=15) matched for body mass index and insulin sensitivity based on the homeostatic model assessment of insulin resistance. INTERVENTION High protein mixed meal of complete food products. MEASUREMENTS Circulating amino acid concentrations were determined hourly before and for 5 hours after meal ingestion. RESULTS There was no difference between cohorts in postprandial appearance of non-essential amino acids, or area under the curve of any individual amino acid or amino acid class. However, older adults had higher baseline concentrations of aspartic acid, glutamic acid, glycine, ornithine, threonine and tyrosine and lower baseline concentrations of hydroxyproline, isoleucine, leucine, methionine and valine compared to younger adults. Younger adults showed peak essential (EAA) and branched-chain amino acid (BCAA) concentrations at 1 hour post meal while older adults' peak EAA and BCAA concentration was at 3 hours. Similarly, peak total amino acid concentrations were at 3 hours in older adults. CONCLUSION Older adults digested and absorbed the protein within a mixed meal more slowly than younger adults. Delayed absorption of AA following a mixed meal of complete food products may suppress or delay protein synthesis in senescent muscle.
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Affiliation(s)
- A M Milan
- Cameron Mitchell, The Liggins Institute, University of Auckland, 85 Park Road, Grafton, Private Bag 92019, Auckland 1023, New Zealand. Tel: +64 (09) 9236606, Fax: (+64 9) 373 7039,
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Myostatin Activates the Ubiquitin-Proteasome and Autophagy-Lysosome Systems Contributing to Muscle Wasting in Chronic Kidney Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:684965. [PMID: 26448817 PMCID: PMC4584061 DOI: 10.1155/2015/684965] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/18/2014] [Accepted: 12/11/2014] [Indexed: 12/24/2022]
Abstract
Our evidence demonstrated that CKD upregulated the expression of myostatin, TNF-α, and p-IkBa and downregulated the phosphorylation of PI3K, Akt, and FoxO3a, which were also associated with protein degradation and muscle atrophy. The autophagosome formation and protein expression of autophagy-related genes were increased in muscle of CKD rats. The mRNA level and protein expression of MAFbx and MuRF-1 were also upregulated in CKD rats, as well as proteasome activity of 26S. Moreover, activation of myostatin elicited by TNF-α induces C2C12 myotube atrophy via upregulating the expression of autophagy-related genes, including MAFbx and MuRF1 and proteasome subunits. Inactivation of FoxO3a triggered by PI3K inhibitor LY294002 prevented the myostatin-induced increase of expression of MuRF1, MAFbx, and LC3-II protein in C2C12 myotubes. The findings were further consolidated by using siRNA interference and overexpression of myostatin. Additionally, expression of myostatin was activated by TNF-α via a NF-κB dependent pathway in C2C12 myotubes, while inhibition of NF-κB activity suppressed myostatin and improved myotube atrophy. Collectively, myostatin mediated CKD-induced muscle catabolism via coordinate activation of the autophagy and the ubiquitin-proteasome systems.
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Reviewing the Effects of L-Leucine Supplementation in the Regulation of Food Intake, Energy Balance, and Glucose Homeostasis. Nutrients 2015; 7:3914-37. [PMID: 26007339 PMCID: PMC4446786 DOI: 10.3390/nu7053914] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 04/30/2015] [Accepted: 05/12/2015] [Indexed: 12/18/2022] Open
Abstract
Leucine is a well-known activator of the mammalian target of rapamycin (mTOR). Because mTOR signaling regulates several aspects of metabolism, the potential of leucine as a dietary supplement for treating obesity and diabetes mellitus has been investigated. The objective of the present review was to summarize and discuss the available evidence regarding the mechanisms and the effects of leucine supplementation on the regulation of food intake, energy balance, and glucose homeostasis. Based on the available evidence, we conclude that although central leucine injection decreases food intake, this effect is not well reproduced when leucine is provided as a dietary supplement. Consequently, no robust evidence indicates that oral leucine supplementation significantly affects food intake, although several studies have shown that leucine supplementation may help to decrease body adiposity in specific conditions. However, more studies are necessary to assess the effects of leucine supplementation in already-obese subjects. Finally, although several studies have found that leucine supplementation improves glucose homeostasis, the underlying mechanisms involved in these potential beneficial effects remain unknown and may be partially dependent on weight loss.
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Walrand S, Gryson C, Salles J, Giraudet C, Migné C, Bonhomme C, Le Ruyet P, Boirie Y. Fast-digestive protein supplement for ten days overcomes muscle anabolic resistance in healthy elderly men. Clin Nutr 2015; 35:660-8. [PMID: 26008820 DOI: 10.1016/j.clnu.2015.04.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 04/13/2015] [Accepted: 04/19/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND/OBJECTIVE Adequate protein intake is crucial to maintain muscle protein content in elderly subjects, but quality of dietary proteins should be considered. The aim was to determine whether soluble milk protein offers an original strategy to increase muscle anabolism in elderly subjects via a synergistic effect of fast-digesting proteins together with a unique essential AA content. DESIGN We investigated the effect of a 10-day adequate-protein (AP) or high-protein (HP) diet together with the protein source as caseins (CAS) or soluble milk proteins (PRO) on specific muscle protein fractional synthesis rates (FSRs) in healthy elderly men (71.8 ± 2.4 yr, n = 31). The isotopic study consisted of two periods of 4 h each: a post-absorptive and a postprandial period. The fed state was defined by consumption of either 15 g or 30 g of PRO or CAS, given fractionally every 20 min for 4 h. Soluble milk proteins are produced using a membrane process directly from pasteurized milk. MEASUREMENTS Specific muscle protein FSRs were measured during both postabsorptive and postprandial period using a continuous infusion of l-[1-(13)C]leucine. RESULTS FSR of sarcoplasmic muscle proteins and actin did not increase significantly in the postprandial state compared to postabsorptive state, whereas myosin FSR rate was increased by feeding whatever the protein source in HP groups (0.024 ± 0.005 vs 0.053 ± 0.011% h(-1), P < 0.05 and 0.026 ± 0.004 vs 0.050 ± 0.005% h(-1), P < 0.004 for PRO HP and CAS HP) but only with the PRO meal in the AP groups (0.031 ± 0.003 vs 0.062 ± 0.009% h(-1), P < 0.03 for PRO AP). Mitochondrial muscle protein FSR was also increased by feeding, irrespective of the protein quantity, but only in PRO meal groups (P < 0.02). CONCLUSION Fast-digesting soluble milk proteins improved postprandial muscle protein synthesis, especially mitochondrial muscle proteins and myosin fractional synthesis rates, in elderly subjects.
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Affiliation(s)
- Stéphane Walrand
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
| | - Céline Gryson
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
| | - Jérôme Salles
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
| | - Christophe Giraudet
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
| | - Carole Migné
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
| | | | | | - Yves Boirie
- INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France; Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France; CHU Clermont-Ferrand, Clinical Nutrition Department, Clermont-Ferrand F-63003, France.
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Trabal J, Forga M, Leyes P, Torres F, Rubio J, Prieto E, Farran-Codina A. Effects of free leucine supplementation and resistance training on muscle strength and functional status in older adults: a randomized controlled trial. Clin Interv Aging 2015; 10:713-23. [PMID: 25926725 PMCID: PMC4403814 DOI: 10.2147/cia.s75271] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE To assess the effect of free leucine supplementation combined with resistance training versus resistance training only on muscle strength and functional status in older adults. METHODS This was a randomized, double-blind, placebo-controlled, parallel study with two intervention groups. Thirty older adults were randomly assigned to receive either 10 g leucine/day (leucine group [LG], n=15) or a placebo (control group [CG], n=15), plus resistance training over a 12-week period. Maximal overcoming isometric leg strength, functional status, nutritional status, body composition, health-related quality of life, depression, and dietary intake were assessed at 4 and 12 weeks. Missing data at 12 weeks were handled using mixed models for repeated measurements for data imputation. RESULTS Twenty-four subjects completed the 4-week assessment and eleven completed the 12-week intervention. Clinically significant gains were found in isometric leg strength at both assessment time points. Analysis of the effect size also showed how participants in LG outperformed those in CG for chair stands and the timed up and go test. No significant changes were observed for the rest of the outcomes. CONCLUSION Our combined analysis showed moderate changes in isometric leg muscle strength and certain components of functional status. The magnitude of changes found on these outcomes should be qualified as a positive effect of the concomitant intervention.
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Affiliation(s)
- Joan Trabal
- Department of Endocrinology and Nutrition, Hospital Clínic Universitari de Barcelona, Barcelona, Catalonia, Spain
| | - Maria Forga
- Department of Endocrinology and Nutrition, Hospital Clínic Universitari de Barcelona, Barcelona, Catalonia, Spain
| | - Pere Leyes
- Department of Endocrinology and Nutrition, Hospital Clínic Universitari de Barcelona, Barcelona, Catalonia, Spain
| | - Ferran Torres
- Biostatistics and Data Management Core Facility, IDIBAPS, Hospital Clinic Universitari de Barcelona, Barcelona, Catalonia, Spain ; Biostatistics Unit, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
| | - Jordi Rubio
- Residencia Ballesol Almogavers, Grupo Ballesol, Barcelona, Catalonia, Spain
| | - Esther Prieto
- Centre de Rehabilitacio, Fundació Amiba, Badalona, Catalonia, Spain
| | - Andreu Farran-Codina
- Department of Nutrition and Food Science, Faculty of Pharmacy, Universitat de Barcelona, Barcelona, Catalonia, Spain
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Kelleher AR, Pereira SL, Jefferson LS, Kimball SR. REDD2 expression in rat skeletal muscle correlates with nutrient-induced activation of mTORC1: responses to aging, immobilization, and remobilization. Am J Physiol Endocrinol Metab 2015; 308:E122-9. [PMID: 25406262 PMCID: PMC4297780 DOI: 10.1152/ajpendo.00341.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In a previous study (Kelleher AR, Kimball SR, Dennis MD, Schilder RJ, and Jefferson LS. Am J Physiol Endocrinol Metab 304: E229-236, 2013.), we observed a rapid (i.e., 1-3 days) immobilization-induced repression of mechanistic target of rapamycin complex 1 (mTORC1) signaling in hindlimb skeletal muscle of young (2-mo-old) rats that was associated with elevated expression of regulated in development and DNA-damage response (REDD) 1 and REDD2. The present study extends that observation to include an assessment of those parameters in soleus muscle of the immobilized hindlimb of various-aged rats as well as in response to remobilization. Male Sprague-Dawley rats aged 2, 9, and 18 mo were subjected to unilateral hindlimb immobilization for 7 days, whereas one group of the 9-mo-old animals underwent 7 days of remobilization. Soleus muscle mass-to-body mass ratio declined with age, with the loss of muscle mass following hindlimb immobilization being inversely proportional to age. Compared with 2-mo-old rats, the older rats exhibited reduced mTORC1 signaling in the nonimmobilized limb in association with elevated REDD2, but not REDD1, mRNA expression. In the 2-mo-old rats, 7 days of hindlimb immobilization attenuated mTORC1 signaling and induced REDD2, but not REDD1, mRNA expression. In contrast, hindlimb immobilization did not further attenuate the age-related reduction in mTORC1 signaling nor further enhance the age-related induction of REDD2 mRNA expression in 9- and 18-mo-old rats. Across ages, REDD1 mRNA was not impacted by immobilization. Finally, remobilization elevated mTORC1 signaling and lowered REDD2 mRNA expression, with no impact on REDD1 gene expression. In conclusion, changes in mTORC1 signaling associated with aging, immobilization, and remobilization were inversely proportional to alterations in REDD2 mRNA expression.
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Affiliation(s)
- Andrew R Kelleher
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania; and
| | | | - Leonard S Jefferson
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania; and
| | - Scot R Kimball
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania; and
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Mosoni L, Gatineau E, Gatellier P, Migné C, Savary-Auzeloux I, Rémond D, Rocher E, Dardevet D. High whey protein intake delayed the loss of lean body mass in healthy old rats, whereas protein type and polyphenol/antioxidant supplementation had no effects. PLoS One 2014; 9:e109098. [PMID: 25268515 PMCID: PMC4182511 DOI: 10.1371/journal.pone.0109098] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 07/21/2014] [Indexed: 12/16/2022] Open
Abstract
Our aim was to compare and combine 3 nutritional strategies to slow down the age-related loss of muscle mass in healthy old rats: 1) increase protein intake, which is likely to stimulate muscle protein anabolism; 2) use leucine rich, rapidly digested whey proteins as protein source (whey proteins are recognized as the most effective proteins to stimulate muscle protein anabolism). 3) Supplement animals with a mixture of chamomile extract, vitamin E, vitamin D (reducing inflammation and oxidative stress is also effective to improve muscle anabolism). Such comparisons and combinations were never tested before. Nutritional groups were: casein 12% protein, whey 12% protein, whey 18% protein and each of these groups were supplemented or not with polyphenols/antioxidants. During 6 months, we followed changes of weight, food intake, inflammation (plasma fibrinogen and alpha-2-macroglobulin) and body composition (DXA). After 6 months, we measured muscle mass, in vivo and ex-vivo fed and post-absorptive muscle protein synthesis, ex-vivo muscle proteolysis, and oxidative stress parameters (liver and muscle glutathione, SOD and total antioxidant activities, muscle carbonyls and TBARS). We showed that although micronutrient supplementation reduced inflammation and oxidative stress, the only factor that significantly reduced the loss of lean body mass was the increase in whey protein intake, with no detectable effect on muscle protein synthesis, and a tendency to reduce muscle proteolysis. We conclude that in healthy rats, increasing protein intake is an effective way to delay sarcopenia.
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Affiliation(s)
- Laurent Mosoni
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
- * E-mail:
| | - Eva Gatineau
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
| | - Philippe Gatellier
- INRA (Institut National de la Recherche Agronomique), UR (Unité de Recherche) 370 QuaPA (Qualité des Produits Animaux), Saint-Genès Champanelle, France
| | - Carole Migné
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
| | - Isabelle Savary-Auzeloux
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
| | - Didier Rémond
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
| | | | - Dominique Dardevet
- INRA (Institut National de la Recherche Agronomique), UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Saint Genès Champanelle, France
- Université Clermont 1, UFR (Unité de Formation et de Recherche) Médecine, UMR (Unité Mixte de Recherche) 1019 Nutrition Humaine, Clermont-Ferrand, France
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Tajrishi MM, Sato S, Shin J, Zheng TS, Burkly LC, Kumar A. The TWEAK-Fn14 dyad is involved in age-associated pathological changes in skeletal muscle. Biochem Biophys Res Commun 2014; 446:1219-1224. [PMID: 24680686 DOI: 10.1016/j.bbrc.2014.03.084] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Accepted: 03/18/2014] [Indexed: 12/22/2022]
Abstract
Progressive loss of skeletal muscle mass and strength (sarcopenia) is a major clinical problem in the elderly. Recently, proinflammatory cytokine TWEAK and its receptor Fn14 were identified as key mediators of muscle wasting in various catabolic states. However, the role of the TWEAK-Fn14 pathway in pathological changes in skeletal muscle during aging remains unknown. In this study, we demonstrate that the levels of Fn14 are increased in skeletal muscle of 18-month old (aged) mice compared with adult mice. Genetic ablation of Fn14 significantly increased the levels of specific muscle proteins and blunted the age-associated fiber atrophy in mice. While gene expression of two prominent muscle-specific E3 ubiquitin ligases MAFBx and MuRF1 remained comparable, levels of ubiquitinated proteins and the expression of autophagy-related molecule Atg12 were significantly reduced in Fn14-knockout (KO) mice compared with wild-type mice during aging. Ablation of Fn14 significantly diminished the DNA-binding activity of transcription factor nuclear factor-kappa B (NF-κB), gene expression of various inflammatory molecules, and interstitial fibrosis in skeletal muscle of aged mice. Collectively, our study suggests that the TWEAK-Fn14 signaling axis contributes to age-associated muscle atrophy and fibrosis potentially through its local activation of proteolytic systems and inflammatory pathways.
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Affiliation(s)
- Marjan M Tajrishi
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Shuichi Sato
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Jonghyun Shin
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202
| | - Timothy S Zheng
- Department of Immunology, Biogen Idec, 14 Cambridge Center, Cambridge, MA 02142
| | - Linda C Burkly
- Department of Immunology, Biogen Idec, 14 Cambridge Center, Cambridge, MA 02142
| | - Ashok Kumar
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202
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Supplementation of ketoacids contributes to the up-regulation of the Wnt7a/Akt/p70S6K pathway and the down-regulation of apoptotic and ubiquitin–proteasome systems in the muscle of 5/6 nephrectomised rats. Br J Nutr 2014; 111:1536-48. [DOI: 10.1017/s0007114513004091] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Ketoacids (KA) are known to improve muscle mass among patients with chronic kidney disease (CKD) on a low-protein diet (CKD-LPD), but the mechanism of its preventive effects on muscle atrophy still remains unclear. Since muscle atrophy in CKD may be attributable to the down-regulation of the Wnt7a/Akt/p70S6K pathway and the activation of the ubiquitin–proteasome system (UPS) and the apoptotic signalling pathway, a hypothesis can readily be drawn that KA supplementation improves muscle mass by up-regulating the Wnt7a/Akt/p70S6K pathway and counteracting the activation of the UPS and caspase-3-dependent apoptosis in the muscle of CKD-LPD rats. Rats with 5/6 nephrectomy were randomly divided into three groups, and fed with either 22 % protein (normal-protein diet; NPD), 6 % protein (LPD) or 5 % protein plus 1 % KA for 24 weeks. Sham-operated rats with NPD intake were used as the control. The results demonstrated that KA supplementation improved protein synthesis and increased related mediators such as Wnt7a, phosphorylated Akt and p70S6K in the muscle of CKD-LPD rats. It also inhibited protein degradation, withheld the increase in ubiquitin and its ligases MAFbx (muscle atrophy F-box) and MuRF1 (muscle ring finger-1) as well as attenuated proteasome activity in the muscle of CKD-LPD rats. Moreover, KA supplementation gave rise to a reduction in DNA fragment, cleaved caspase-3 and 14 kDa actin fragment via the down-regulation of the Bax:Bcl-2 ratio in the muscle of CKD-LPD rats. The beneficial effects unveiled herein further consolidate that KA may be a better therapeutic strategy for muscle atrophy in CKD-LPD.
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Pereira MG, Baptista IL, Carlassara EOC, Moriscot AS, Aoki MS, Miyabara EH. Leucine supplementation improves skeletal muscle regeneration after cryolesion in rats. PLoS One 2014; 9:e85283. [PMID: 24416379 PMCID: PMC3885703 DOI: 10.1371/journal.pone.0085283] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 11/25/2013] [Indexed: 12/31/2022] Open
Abstract
This study was undertaken in order to provide further insight into the role of leucine supplementation in the skeletal muscle regeneration process, focusing on myofiber size and strength recovery. Young (2-month-old) rats were subjected or not to leucine supplementation (1.35 g/kg per day) started 3 days prior to cryolesion. Then, soleus muscles were cryolesioned and continued receiving leucine supplementation until 1, 3 and 10 days later. Soleus muscles from leucine-supplemented animals displayed an increase in myofiber size and a reduction in collagen type III expression on post-cryolesion day 10. Leucine was also effective in reducing FOXO3a activation and ubiquitinated protein accumulation in muscles at post-cryolesion days 3 and 10. In addition, leucine supplementation minimized the cryolesion-induced decrease in tetanic strength and increase in fatigue in regenerating muscles at post-cryolesion day 10. These beneficial effects of leucine were not accompanied by activation of any elements of the phosphoinositide 3-kinase/Akt/mechanistic target of rapamycin signalling pathway in the regenerating muscles. Our results show that leucine improves myofiber size gain and strength recovery in regenerating soleus muscles through attenuation of protein ubiquitination. In addition, leucine might have therapeutic effects for muscle recovery following injury and in some muscle diseases.
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Affiliation(s)
- Marcelo G. Pereira
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Igor L. Baptista
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Eduardo O. C. Carlassara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Anselmo S. Moriscot
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Marcelo S. Aoki
- School of Arts, Sciences and Humanities, University of Sao Paulo, Sao Paulo, Brazil
| | - Elen H. Miyabara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
- * E-mail:
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Oral leucine supplementation is sensed by the brain but neither reduces food intake nor induces an anorectic pattern of gene expression in the hypothalamus. PLoS One 2013; 8:e84094. [PMID: 24349566 PMCID: PMC3862776 DOI: 10.1371/journal.pone.0084094] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 11/15/2013] [Indexed: 11/19/2022] Open
Abstract
Leucine activates the intracellular mammalian target of the rapamycin (mTOR) pathway, and hypothalamic mTOR signaling regulates food intake. Although central infusion of leucine reduces food intake, it is still uncertain whether oral leucine supplementation is able to affect the hypothalamic circuits that control energy balance. We observed increased phosphorylation of p70s6k in the mouse hypothalamus after an acute oral gavage of leucine. We then assessed whether acute oral gavage of leucine induces the activation of neurons in several hypothalamic nuclei and in the brainstem. Leucine did not induce the expression of Fos in hypothalamic nuclei, but it increased the number of Fos-immunoreactive neurons in the area postrema. In addition, oral gavage of leucine acutely increased the 24 h food intake of mice. Nonetheless, chronic leucine supplementation in the drinking water did not change the food intake and the weight gain of ob/ob mice and of wild-type mice consuming a low- or a high-fat diet. We assessed the hypothalamic gene expression and observed that leucine supplementation increased the expression of enzymes (BCAT1, BCAT2 and BCKDK) that metabolize branched-chain amino acids. Despite these effects, leucine supplementation did not induce an anorectic pattern of gene expression in the hypothalamus. In conclusion, our data show that the brain is able to sense oral leucine intake. However, the food intake is not modified by chronic oral leucine supplementation. These results question the possible efficacy of leucine supplementation as an appetite suppressant to treat obesity.
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Savary-Auzeloux I, Magne H, Migné C, Oberli M, Breuillé D, Faure M, Vidal K, Perrot M, Rémond D, Combaret L, Dardevet D. A dietary supplementation with leucine and antioxidants is capable to accelerate muscle mass recovery after immobilization in adult rats. PLoS One 2013; 8:e81495. [PMID: 24312309 PMCID: PMC3843669 DOI: 10.1371/journal.pone.0081495] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 10/14/2013] [Indexed: 11/18/2022] Open
Abstract
Prolonged inactivity induces muscle loss due to an activation of proteolysis and decreased protein synthesis; the latter is also involved in the recovery of muscle mass. The aim of the present work was to explore the evolution of muscle mass and protein metabolism during immobilization and recovery and assess the effect of a nutritional strategy for counteracting muscle loss and facilitating recovery. Adult rats (6–8 months) were subjected to unilateral hindlimb casting for 8 days (I0–I8) and then permitted to recover for 10 to 40 days (R10–R40). They were fed a Control or Experimental diet supplemented with antioxidants/polyphenols (AOX) (I0 to I8), AOX and leucine (AOX + LEU) (I8 to R15) and LEU alone (R15 to R40). Muscle mass, absolute protein synthesis rate and proteasome activities were measured in gastrocnemius muscle in casted and non-casted legs in post prandial (PP) and post absorptive (PA) states at each time point. Immobilized gastrocnemius protein content was similarly reduced (-37%) in both diets compared to the non-casted leg. Muscle mass recovery was accelerated by the AOX and LEU supplementation (+6% AOX+LEU vs. Control, P<0.05 at R40) due to a higher protein synthesis both in PA and PP states (+23% and 31% respectively, Experimental vs. Control diets, P<0.05, R40) without difference in trypsin- and chymotrypsin-like activities between diets. Thus, this nutritional supplementation accelerated the recovery of muscle mass via a stimulation of protein synthesis throughout the entire day (in the PP and PA states) and could be a promising strategy to be tested during recovery from bed rest in humans.
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Affiliation(s)
- Isabelle Savary-Auzeloux
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
- * E-mail:
| | - Hugues Magne
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
| | - Carole Migné
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
| | - Marion Oberli
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
| | - Denis Breuillé
- Nestlé Research Center, Vers-chez-les-Blanc, Lausanne, Switzerland
| | - Magali Faure
- Nestlé Research Center, Vers-chez-les-Blanc, Lausanne, Switzerland
| | - Karine Vidal
- Nestlé Research Center, Vers-chez-les-Blanc, Lausanne, Switzerland
| | - Marie Perrot
- Nestlé Research Center, Vers-chez-les-Blanc, Lausanne, Switzerland
| | - Didier Rémond
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
| | - Lydie Combaret
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
| | - Dominique Dardevet
- Clermont Université, Université d'Auvergne, Unité de Nutrition Humaine, BP 10448, Clermont-Ferrand, France
- INRA, UMR 1019, UNH, CRNH Auvergne, Clermont-Ferrand, France
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Martin V, Ratel S, Siracusa J, Le Ruyet P, Savary-Auzeloux I, Combaret L, Guillet C, Dardevet D. Whey proteins are more efficient than casein in the recovery of muscle functional properties following a casting induced muscle atrophy. PLoS One 2013; 8:e75408. [PMID: 24069411 PMCID: PMC3777906 DOI: 10.1371/journal.pone.0075408] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 08/14/2013] [Indexed: 11/18/2022] Open
Abstract
The purpose of this study was to investigate the effect of whey supplementation, as compared to the standard casein diet, on the recovery of muscle functional properties after a casting-induced immobilization period. After an initial (I0) evaluation of the contractile properties of the plantarflexors (isometric torque-frequency relationship, concentric power-velocity relationship and a fatigability test), the ankle of 20 male adult rats was immobilized by casting for 8 days. During this period, rats were fed a standard diet with 13% of casein (CAS). After cast removal, rats received either the same diet or a diet with 13% of whey proteins (WHEY). A control group (n = 10), non-immobilized but pair-fed to the two other experimental groups, was also studied and fed with the CAS diet. During the recovery period, contractile properties were evaluated 7 (R7), 21 (R21) and 42 days (R42) after cast removal. The immobilization procedure induced a homogeneous depression of average isometric force at R7 (CAS: − 19.0±8.2%; WHEY: − 21.7±8.4%; P<0.001) and concentric power (CAS: − 26.8±16.4%, P<0.001; WHEY: − 13.5±21.8%, P<0.05) as compared to I0. Conversely, no significant alteration of fatigability was observed. At R21, isometric force had fully recovered in WHEY, especially for frequencies above 50 Hz, whereas it was still significantly depressed in CAS, where complete recovery occurred only at R42. Similarly, recovery of concentric power was faster at R21 in the 500−700°/s range in the WHEY group. These results suggest that recovery kinetics varied between diets, the diet with the whey proteins promoting a faster recovery of isometric force and concentric power output as compared to the casein diet. These effects were more specifically observed at force level and movement velocities that are relevant for functional abilities, and thus natural locomotion.
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Affiliation(s)
- Vincent Martin
- Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l'Exercice en Conditions Physiologiques et Pathologiques, CRNH Auvergne, Clermont-Ferrand, France
- * E-mail:
| | - Sébastien Ratel
- Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l'Exercice en Conditions Physiologiques et Pathologiques, CRNH Auvergne, Clermont-Ferrand, France
| | - Julien Siracusa
- Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l'Exercice en Conditions Physiologiques et Pathologiques, CRNH Auvergne, Clermont-Ferrand, France
| | | | | | - Lydie Combaret
- INRA, Unité de Nutrition Humaine (UNH, UMR 1019), CRNH Auvergne, Clermont-Ferrand, France
| | - Christelle Guillet
- INRA, Unité de Nutrition Humaine (UNH, UMR 1019), CRNH Auvergne, Clermont-Ferrand, France
- Clermont Université, Université d’Auvergne, Clermont-Ferrand, France
| | - Dominique Dardevet
- INRA, Unité de Nutrition Humaine (UNH, UMR 1019), CRNH Auvergne, Clermont-Ferrand, France
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Unilateral hindlimb casting induced a delayed generalized muscle atrophy during rehabilitation that is prevented by a whey or a high protein diet but not a free leucine-enriched diet. PLoS One 2013; 8:e70130. [PMID: 24015173 PMCID: PMC3754992 DOI: 10.1371/journal.pone.0070130] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 06/17/2013] [Indexed: 11/19/2022] Open
Abstract
Sarcopenia is the general muscle mass and strength loss associated with ageing. Muscle atrophy could be made worse by exposure to acute periods of immobilization, because muscle disuse by itself is a stimulus for atrophy. Using a model of unilateral hindlimb casting in old adult rats, we have already demonstrated that the primary effect of immobilization was atrophy in the casted leg, but was also surprisingly associated with a retarded atrophy in the non-casted leg during rehabilitation. In search of mechanisms involved in this generalized atrophy, we demonstrated in the present study that contrary to pair-fed non-immobilized control animals, muscle protein synthesis in the non-immobilized limb was unable to adapt and to respond positively to food intake. Because pair-fed control rats did not lose muscle mass, this defect in muscle protein synthesis may represent one of the explanation for the muscle mass loss observed in the non-immobilized rats. Nevertheless, in order to stimulate protein turn over and generate a positive nitrogen balance required to maintain the whole muscle mass in immobilized rats, we tested a dietary free leucine supplementation (an amino acid known for its stimulatory effect on protein metabolism) during the rehabilitation period. Leucine supplementation was able to overcome the anabolic resistance in the non-immobilized limb. A greater muscle protein synthesis up-regulation associated with a stimulation of the mTOR signalling pathway was indeed recorded but it remained inefficient to prevent the loss of muscle in the non-immobilized limb. By contrast, we demonstrated here that whey protein or high protein diets were able to prevent the muscle mass loss of the non-immobilized limb by sustaining muscle protein synthesis during the entire rehabilitation period.
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Nutritional strategies to counteract muscle atrophy caused by disuse and to improve recovery. Nutr Res Rev 2013; 26:149-65. [PMID: 23930668 DOI: 10.1017/s0954422413000115] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Periods of immobilisation are often associated with pathologies and/or ageing. These periods of muscle disuse induce muscle atrophy which could worsen the pathology or elderly frailty. If muscle mass loss has positive effects in the short term, a sustained/uncontrolled muscle mass loss is deleterious for health. Muscle mass recovery following immobilisation-induced atrophy could be critical, particularly when it is uncompleted as observed during ageing. Exercise, the best way to recover muscle mass, is not always applicable. So, other approaches such as nutritional strategies are needed to limit muscle wasting and to improve muscle mass recovery in such situations. The present review discusses mechanisms involved in muscle atrophy following disuse and during recovery and emphasises the effect of age in these mechanisms. In addition, the efficiency of nutritional strategies proposed to limit muscle mass loss during disuse and to improve protein gain during recovery (leucine supplementation, whey proteins, antioxidants and anti-inflammatory compounds, energy intake) is also discussed.
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Bodine SC. Disuse-induced muscle wasting. Int J Biochem Cell Biol 2013; 45:2200-8. [PMID: 23800384 DOI: 10.1016/j.biocel.2013.06.011] [Citation(s) in RCA: 245] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 06/11/2013] [Accepted: 06/12/2013] [Indexed: 12/17/2022]
Abstract
Loss of skeletal muscle mass occurs frequently in clinical settings in response to joint immobilization and bed rest, and is induced by a combination of unloading and inactivity. Disuse-induced atrophy will likely affect every person in his or her lifetime, and can be debilitating especially in the elderly. Currently there are no good therapies to treat disuse-induced muscle atrophy, in part, due to a lack of understanding of the cellular and molecular mechanisms responsible for the induction and maintenance of muscle atrophy. Our current understanding of disuse atrophy comes from the investigation of a variety of models (joint immobilization, hindlimb unloading, bed rest, spinal cord injury) in both animals and humans. Under conditions of unloading, it is widely accepted that there is a decrease in protein synthesis, however, the role of protein degradation, especially in humans, is debated. This review will examine the current understanding of the molecular and cellular mechanisms regulating muscle loss under disuse conditions, discussing the similarities and areas of dispute between the animal and human literature. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.
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Affiliation(s)
- Sue C Bodine
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, One Shields Avenue, Davis, CA 95616, United States.
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Kelleher AR, Kimball SR, Dennis MD, Schilder RJ, Jefferson LS. The mTORC1 signaling repressors REDD1/2 are rapidly induced and activation of p70S6K1 by leucine is defective in skeletal muscle of an immobilized rat hindlimb. Am J Physiol Endocrinol Metab 2013; 304. [PMID: 23193052 PMCID: PMC3543567 DOI: 10.1152/ajpendo.00409.2012] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Limb immobilization, limb suspension, and bed rest cause substantial loss of skeletal muscle mass, a phenomenon termed disuse atrophy. To acquire new knowledge that will assist in the development of therapeutic strategies for minimizing disuse atrophy, the present study was undertaken with the aim of identifying molecular mechanisms that mediate control of protein synthesis and mechanistic target of rapamycin complex 1 (mTORC1) signaling. Male Sprague-Dawley rats were subjected to unilateral hindlimb immobilization for 1, 2, 3, or 7 days or served as nonimmobilized controls. Following an overnight fast, rats received either saline or L-leucine by oral gavage as a nutrient stimulus. Hindlimb skeletal muscles were extracted 30 min postgavage and analyzed for the rate of protein synthesis, mRNA expression, phosphorylation state of key proteins in the mTORC1 signaling pathway, and mTORC1 signaling repressors. In the basal state, mTORC1 signaling and protein synthesis were repressed within 24 h in the soleus of an immobilized compared with a nonimmobilized hindlimb. These responses were accompanied by a concomitant induction in expression of the mTORC1 repressors regulated in development and DNA damage responses (REDD) 1/2. The nutrient stimulus produced an elevation of similar magnitude in mTORC1 signaling in both the immobilized and nonimmobilized muscle. In contrast, phosphorylation of 70-kDa ribosomal protein S6 kinase 1 (p70S6K1) on Thr(229) and Thr(389) in response to the nutrient stimulus was severely blunted. Phosphorylation of Thr(229) by PDK1 is a prerequisite for phosphorylation of Thr(389) by mTORC1, suggesting that signaling through PDK1 is impaired in response to immobilization. In conclusion, the results show an immobilization-induced attenuation of mTORC1 signaling mediated by induction of REDD1/2 and defective p70S6K1 phosphorylation.
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Affiliation(s)
- Andrew R Kelleher
- Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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Dardevet D, Rémond D, Peyron MA, Papet I, Savary-Auzeloux I, Mosoni L. Muscle wasting and resistance of muscle anabolism: the "anabolic threshold concept" for adapted nutritional strategies during sarcopenia. ScientificWorldJournal 2012; 2012:269531. [PMID: 23326214 PMCID: PMC3541599 DOI: 10.1100/2012/269531] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 12/03/2012] [Indexed: 01/06/2023] Open
Abstract
Skeletal muscle loss is observed in several physiopathological situations. Strategies to prevent, slow down, or increase recovery of muscle have already been tested. Besides exercise, nutrition, and more particularly protein nutrition based on increased amino acid, leucine or the quality of protein intake has generated positive acute postprandial effect on muscle protein anabolism. However, on the long term, these nutritional strategies have often failed in improving muscle mass even if given for long periods of time in both humans and rodent models. Muscle mass loss situations have been often correlated to a resistance of muscle protein anabolism to food intake which may be explained by an increase of the anabolic threshold toward the stimulatory effect of amino acids. In this paper, we will emphasize how this anabolic resistance may affect the intensity and the duration of the muscle anabolic response at the postprandial state and how it may explain the negative results obtained on the long term in the prevention of muscle mass. Sarcopenia, the muscle mass loss observed during aging, has been chosen to illustrate this concept but it may be kept in mind that it could be extended to any other catabolic states or recovery situations.
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Affiliation(s)
- Dominique Dardevet
- Clermont Université and Unité de Nutrition Humaine, Université d'Auvergne, BP 10448, 63000 Clermont-Ferrand, France.
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Slimani L, Micol D, Amat J, Delcros G, Meunier B, Taillandier D, Polge C, Béchet D, Dardevet D, Picard B, Attaix D, Listrat A, Combaret L. The worsening of tibialis anterior muscle atrophy during recovery post-immobilization correlates with enhanced connective tissue area, proteolysis, and apoptosis. Am J Physiol Endocrinol Metab 2012; 303:E1335-47. [PMID: 23032683 DOI: 10.1152/ajpendo.00379.2012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sustained muscle wasting due to immobilization leads to weakening and severe metabolic consequences. The mechanisms responsible for muscle recovery after immobilization are poorly defined. Muscle atrophy induced by immobilization worsened in the lengthened tibialis anterior (TA) muscle but not in the shortened gastrocnemius muscle. Here, we investigated some mechanisms responsible for this differential response. Adult rats were subjected to unilateral hindlimb casting for 8 days (I8). Casts were removed at I8, and animals were allowed to recover for 10 days (R1 to R10). The worsening of TA atrophy following immobilization occurred immediately after cast removal at R1 and was sustained until R10. This atrophy correlated with a decrease in type IIb myosin heavy chain (MyHC) isoform and an increase in type IIx, IIa, and I isoforms, with muscle connective tissue thickening, and with increased collagen (Col) I mRNA levels. Increased Col XII, Col IV, and Col XVIII mRNA levels during TA immobilization normalized at R6. Sustained enhanced peptidase activities of the proteasome and apoptosome activity contributed to the catabolic response during the studied recovery period. Finally, increased nuclear apoptosis prevailed only in the connective tissue compartment of the TA. Altogether, the worsening of the TA atrophy pending immediate reloading reflects a major remodeling of its fiber type properties and alterations in the structure/composition of the extracellular compartment that may influence its elasticity/stiffness. The data suggest that sustained enhanced ubiquitin-proteasome-dependent proteolysis and apoptosis are important for these adaptations and provide some rationale for explaining the atrophy of reloaded muscles pending immobilization in a lengthened position.
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Affiliation(s)
- Lamia Slimani
- Institut National de Recherche Agronomique (INRA), Unite Mixte de Recherche (UMR), 1019 Unité de Nutrition Humaine 63122, Saint Genès Champanelle, France
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Knuiman P, Kramer IF. Contributions to the understanding of the anabolic properties of different dietary proteins. J Physiol 2012; 590:2839-40. [PMID: 22707594 DOI: 10.1113/jphysiol.2012.233684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Pim Knuiman
- Department of Human Movement Sciences, Maastricht University Medical Centre+ (MUMC+), Maastricht, The Netherlands.
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Breen L, Churchward-Venne TA. Leucine: a nutrient 'trigger' for muscle anabolism, but what more? J Physiol 2012; 590:2065-6. [PMID: 22548909 PMCID: PMC3447149 DOI: 10.1113/jphysiol.2012.230631] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- L Breen
- Department of Kinesiology, McMasterUniversity, Hamilton, Ontario, Canada.
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