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Laskin GR, Rentería LI, Muller-Delp JM, Kim JS, Chase PB, Hwang HS, Gordon BS. Short-term aerobic exercise prevents development of glucocorticoid myopathic features in aged skeletal muscle in a sex-dependent manner. J Physiol 2024. [PMID: 38861348 DOI: 10.1113/jp286334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 05/28/2024] [Indexed: 06/13/2024] Open
Abstract
Older adults are vulnerable to glucocorticoid-induced muscle atrophy and weakness, with sex potentially influencing their susceptibility to those effects. Aerobic exercise can reduce glucocorticoid-induced muscle atrophy in young rodents. However, it is unknown whether aerobic exercise can prevent glucocorticoid myopathy in aged muscle. The objectives of this study were to define the extent to which sex influences the development of glucocorticoid myopathy in aged muscle, and to determine the extent to which aerobic exercise training protects against myopathy development. Twenty-four-month-old female (n = 30) and male (n = 33) mice were randomized to either sedentary or aerobic exercise groups. Within their respective groups, mice were randomized to either daily treatment with dexamethasone (DEX) or saline. Upon completing treatments, the contractile properties of the triceps surae complex were assessed in situ. DEX marginally lowered muscle mass and soluble protein content in both sexes, which was attenuated by aerobic exercise only in females. DEX increased sub-tetanic force and rate of force development only in females, which was not influenced by aerobic exercise. Muscle fatigue was higher in both sexes following DEX, but aerobic exercise prevented fatigue induction only in females. The sex-specific differences to muscle function in response to DEX treatment coincided with sex-specific changes to the content of proteins related to calcium handling, mitochondrial quality control, reactive oxygen species production, and glucocorticoid receptor in muscle. These findings define several important sexually dimorphic changes to aged skeletal muscle physiology in response to glucocorticoid treatment and define the capacity of short-term aerobic exercise to protect against those changes. KEY POINTS: There are sexually dimorphic effects of glucocorticoids on aged skeletal muscle physiology. Glucocorticoid-induced changes to aged muscle contractile properties coincide with sex-specific differences in the content of calcium handling proteins. Aerobic exercise prevents glucocorticoid-induced fatigue only in aged females and coincides with differences in the content of mitochondrial quality control proteins and glucocorticoid receptors.
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Affiliation(s)
- Grant R Laskin
- Department of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, USA
| | - Liliana I Rentería
- Department of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, USA
- Institute of Sports Sciences and Medicine, Florida State University, Tallahassee, Florida, USA
| | - Judy M Muller-Delp
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Jeong-Su Kim
- Department of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, USA
| | - P Bryant Chase
- Department of Biological Science, Florida State University, Tallahassee, Florida, USA
| | - Hyun Seok Hwang
- Department of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, USA
| | - Bradley S Gordon
- Department of Health, Nutrition, and Food Sciences, Florida State University, Tallahassee, Florida, USA
- Institute of Sports Sciences and Medicine, Florida State University, Tallahassee, Florida, USA
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2
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Wilson JB, Epstein M, Lopez B, Brown AK, Lutfy K, Friedman TC. The role of Neurochemicals, Stress Hormones and Immune System in the Positive Feedback Loops between Diabetes, Obesity and Depression. Front Endocrinol (Lausanne) 2023; 14:1224612. [PMID: 37664841 PMCID: PMC10470111 DOI: 10.3389/fendo.2023.1224612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/25/2023] [Indexed: 09/05/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) and depression are significant public health and socioeconomic issues. They commonly co-occur, with T2DM occurring in 11.3% of the US population, while depression has a prevalence of about 9%, with higher rates among youths. Approximately 31% of patients with T2DM suffer from depressive symptoms, with 11.4% having major depressive disorders, which is twice as high as the prevalence of depression in patients without T2DM. Additionally, over 80% of people with T2DM are overweight or obese. This review describes how T2DM and depression can enhance one another, using the same molecular pathways, by synergistically altering the brain's structure and function and reducing the reward obtained from eating. In this article, we reviewed the evidence that eating, especially high-caloric foods, stimulates the limbic system, initiating Reward Deficiency Syndrome. Analogous to other addictive behaviors, neurochemical changes in those with depression and/or T2DM are thought to cause individuals to increase their food intake to obtain the same reward leading to binge eating, weight gain and obesity. Treating the symptoms of T2DM, such as lowering HbA1c, without addressing the underlying pathways has little chance of eliminating the disease. Targeting the immune system, stress circuit, melatonin, and other alterations may be more effective.
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Affiliation(s)
- Julian B. Wilson
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
| | - Ma’ayan Epstein
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
- Psychiatric Emergency Room, Olive View – University of California, Los Angeles (UCLA) Medical Center, Sylmar, CA, United States
| | - Briana Lopez
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
- Friends Research Institute, Cerritos, CA, United States
| | - Amira K. Brown
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
| | - Kabirullah Lutfy
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
- College of Pharmacy, Western University of Health Sciences, Pomona, CA, United States
| | - Theodore C. Friedman
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, Los Angeles, CA, United States
- Friends Research Institute, Cerritos, CA, United States
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3
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Wang BYH, Hsiao AWT, Shiu HT, Wong N, Wang AYF, Lee CW, Lee OKS, Lee WYW. Mesenchymal stem cells alleviate dexamethasone-induced muscle atrophy in mice and the involvement of ERK1/2 signalling pathway. Stem Cell Res Ther 2023; 14:195. [PMID: 37542297 PMCID: PMC10403871 DOI: 10.1186/s13287-023-03418-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 07/17/2023] [Indexed: 08/06/2023] Open
Abstract
BACKGROUND High dosage of dexamethasone (Dex) is an effective treatment for multiple diseases; however, it is often associated with severe side effects including muscle atrophy, resulting in higher risk of falls and poorer life quality of patients. Cell therapy with mesenchymal stem cells (MSCs) holds promise for regenerative medicine. In this study, we aimed to investigate the therapeutic efficacy of systemic administration of adipose-derived mesenchymal stem cells (ADSCs) in mitigating the loss of muscle mass and strength in mouse model of DEX-induced muscle atrophy. METHODS 3-month-old female C57BL/6 mice were treated with Dex (20 mg/kg body weight, i.p.) for 10 days to induce muscle atrophy, then subjected to intravenous injection of a single dose of ADSCs ([Formula: see text] cells/kg body weight) or vehicle control. The mice were killed 7 days after ADSCs treatment. Body compositions were measured by animal DXA, gastrocnemius muscle was isolated for ex vivo muscle functional test, histological assessment and Western blot, while tibialis anterior muscles were isolated for RNA-sequencing and qPCR. For in vitro study, C2C12 myoblast cells were cultured under myogenic differentiation medium for 5 days following 100 [Formula: see text]M Dex treatment with or without ADSC-conditioned medium for another 4 days. Samples were collected for qPCR analysis and Western blot analysis. Myotube morphology was measured by myosin heavy chain immunofluorescence staining. RESULTS ADSC treatment significantly increased body lean mass (10-20%), muscle wet weight (15-30%) and cross-sectional area (CSA) (~ 33%) in DEX-induced muscle atrophy mice model and down-regulated muscle atrophy-associated genes expression (45-65%). Hindlimb grip strength (~ 37%) and forelimb ex vivo muscle contraction property were significantly improved (~ 57%) in the treatment group. Significant increase in type I fibres (~ 77%) was found after ADSC injection. RNA-sequencing results suggested that ERK1/2 signalling pathway might be playing important role underlying the beneficial effect of ADSC treatment, which was confirmed by ERK1/2 inhibitor both in vitro and in vivo. CONCLUSIONS ADSCs restore the pathogenesis of Dex-induced muscle atrophy with an increased number of type I fibres, stronger muscle strength, faster recovery rate and more anti-fatigue ability via ERK1/2 signalling pathway. The inhibition of muscle atrophy-associated genes by ADSCs offered this treatment as an intervention option for muscle-associated diseases. Taken together, our findings suggested that adipose-derived mesenchymal stem cell therapy could be a new treatment option for patient with Dex-induced muscle atrophy.
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Affiliation(s)
- Belle Yu-Hsuan Wang
- Center for Neuromusculoskeletal Restorative Medicine, CUHK InnoHK Centres, Hong Kong Science Park, Hong Kong
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Allen Wei-Ting Hsiao
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Hoi Ting Shiu
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Nicodemus Wong
- Center for Neuromusculoskeletal Restorative Medicine, CUHK InnoHK Centres, Hong Kong Science Park, Hong Kong
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Amanda Yu-Fan Wang
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Chien-Wei Lee
- Center for Translational Genomics and Regenerative Medicine Research, China Medical University Hospital, China Medical University, Taichung, 404327, Taiwan.
- Department of Biomedical Engineering, China Medical University, Taichung, 404327, Taiwan.
| | - Oscar Kuang-Sheng Lee
- Center for Translational Genomics and Regenerative Medicine Research, China Medical University Hospital, China Medical University, Taichung, 404327, Taiwan.
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
- Department of Orthopedics, China Medical University Hospital, Taichung, 404327, Taiwan.
| | - Wayne Yuk-Wai Lee
- Center for Neuromusculoskeletal Restorative Medicine, CUHK InnoHK Centres, Hong Kong Science Park, Hong Kong.
- Musculoskeletal Research Laboratory, SH Ho Scoliosis Research Laboratory, Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
- Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
- Joint Scoliosis Research Centre of the Chinese University of Hong Kong and Nanjing University, The Chinese University of Hong Kong, Shatin, Hong Kong.
- Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
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4
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Mesenchymal Stem Cell Transplantation for the Treatment of Age-Related Musculoskeletal Frailty. Int J Mol Sci 2021; 22:ijms221910542. [PMID: 34638883 PMCID: PMC8508885 DOI: 10.3390/ijms221910542] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/16/2021] [Accepted: 09/24/2021] [Indexed: 12/16/2022] Open
Abstract
Projected life expectancy continues to grow worldwide owing to the advancement of new treatments and technologies leading to rapid growth of geriatric population. Thus, age-associated diseases especially in the musculoskeletal system are becoming more common. Loss of bone (osteoporosis) and muscle (sarcopenia) mass are conditions whose prevalence is increasing because of the change in population distribution in the world towards an older mean age. The deterioration in the bone and muscle functions can cause severe disability and seriously affects the patients’ quality of life. Currently, there is no treatment to prevent and reverse age-related musculoskeletal frailty. Existing interventions are mainly to slow down and control the signs and symptoms. Mesenchymal stem cell (MSC) transplantation is a promising approach to attenuate age-related musculoskeletal frailty. This review compiles the present knowledge of the causes and changes of the musculoskeletal frailty and the potential of MSC transplantation as a regenerative therapy for age-related musculoskeletal frailty.
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Singanayagam A, Glanville N, Cuthbertson L, Bartlett NW, Finney LJ, Turek E, Bakhsoliani E, Calderazzo MA, Trujillo-Torralbo MB, Footitt J, James PL, Fenwick P, Kemp SV, Clarke TB, Wedzicha JA, Edwards MR, Moffatt M, Cookson WO, Mallia P, Johnston SL. Inhaled corticosteroid suppression of cathelicidin drives dysbiosis and bacterial infection in chronic obstructive pulmonary disease. Sci Transl Med 2020; 11:11/507/eaav3879. [PMID: 31462509 DOI: 10.1126/scitranslmed.aav3879] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 02/12/2019] [Accepted: 07/23/2019] [Indexed: 12/11/2022]
Abstract
Bacterial infection commonly complicates inflammatory airway diseases such as chronic obstructive pulmonary disease (COPD). The mechanisms of increased infection susceptibility and how use of the commonly prescribed therapy inhaled corticosteroids (ICS) accentuates pneumonia risk in COPD are poorly understood. Here, using analysis of samples from patients with COPD, we show that ICS use is associated with lung microbiota disruption leading to proliferation of streptococcal genera, an effect that could be recapitulated in ICS-treated mice. To study mechanisms underlying this effect, we used cellular and mouse models of streptococcal expansion with Streptococcus pneumoniae, an important pathogen in COPD, to demonstrate that ICS impairs pulmonary clearance of bacteria through suppression of the antimicrobial peptide cathelicidin. ICS impairment of pulmonary immunity was dependent on suppression of cathelicidin because ICS had no effect on bacterial loads in mice lacking cathelicidin (Camp -/-) and exogenous cathelicidin prevented ICS-mediated expansion of streptococci within the microbiota and improved bacterial clearance. Suppression of pulmonary immunity by ICS was mediated by augmentation of the protease cathepsin D. Collectively, these data suggest a central role for cathepsin D/cathelicidin in the suppression of antibacterial host defense by ICS in COPD. Therapeutic restoration of cathelicidin to boost antibacterial immunity and beneficially modulate the lung microbiota might be an effective strategy in COPD.
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Affiliation(s)
- Aran Singanayagam
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK.
| | - Nicholas Glanville
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK
| | - Leah Cuthbertson
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Nathan W Bartlett
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK.,Faculty of Health and Medicine and Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute and University of Newcastle, Newcastle, NSW 2305, Australia
| | - Lydia J Finney
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Elena Turek
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Eteri Bakhsoliani
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK
| | | | | | - Joseph Footitt
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK
| | - Phillip L James
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Peter Fenwick
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Samuel V Kemp
- Royal Brompton Hospital, Fulham Road, London SW2 6NP, UK
| | - Thomas B Clarke
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London SW7 2AZ, UK
| | - Jadwiga A Wedzicha
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Michael R Edwards
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK
| | - Miriam Moffatt
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - William O Cookson
- National Heart and Lung Institute, Brompton Campus, Imperial College London, London SW3 6LY, UK
| | - Patrick Mallia
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK
| | - Sebastian L Johnston
- National Heart and Lung Institute, St Mary's Campus, Imperial College London, London W2 1PG, UK.
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6
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Kang W, Tong T, Park T. Corticotropin releasing factor-overexpressing mouse is a model of chronic stress-induced muscle atrophy. PLoS One 2020; 15:e0229048. [PMID: 32049987 PMCID: PMC7015416 DOI: 10.1371/journal.pone.0229048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/28/2020] [Indexed: 12/20/2022] Open
Abstract
Chronic stress and continually high glucocorticoid levels can induce muscle atrophy. Unfortunately, there is a lack of appropriate animal models for stress-induced muscle atrophy research. Corticotropin releasing factor-overexpressing (CRF-OE) mice are a transgenic model of chronic stress that exhibit increased plasma corticosterone levels and Cushing’s syndrome; however, the skeletal muscle pathology of the CRF-OE mouse has not been well studied. We observed that male, 19-week-old CRF-OE mice had significantly lower skeletal muscle mass, average cross-sectional myofiber area, and total muscle protein content than their wild type (WT) littermates. Muscle function determined by grip strength, wire-hang, and open field tests showed that 19-week-old male CRF-OE mice had impaired physical ability. Additionally, the skeletal muscles of CRF-mice exhibited decreased expression of factors involved in the IGF-1/AKT/mTOR protein synthesis pathway and increased ubiquitin proteasome pathway activity compared to the WT control mice. In conclusion, 19-week-old CRF-OE mice display numerous features of muscle atrophy and thus serve as a model for investigating stress-induced muscle atrophy and interventions to target the deleterious effects of stress on skeletal muscle.
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Affiliation(s)
- Wesuk Kang
- Department of Food and Nutrition, Brain Korea 21 PLUS Project, Yonsei University, Seodaemun-gu, Seoul, Korea
| | - Tao Tong
- Department of Food and Nutrition, Brain Korea 21 PLUS Project, Yonsei University, Seodaemun-gu, Seoul, Korea
| | - Taesun Park
- Department of Food and Nutrition, Brain Korea 21 PLUS Project, Yonsei University, Seodaemun-gu, Seoul, Korea
- * E-mail:
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7
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Alev K, Vain A, Aru M, Pehme A, Purge P, Kaasik P, Seene T. Glucocorticoid-Induced Changes in Rat Skeletal Muscle Biomechanical and Viscoelastic Properties: Aspects of Aging. J Manipulative Physiol Ther 2019; 41:19-24. [PMID: 29366489 DOI: 10.1016/j.jmpt.2017.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 05/30/2017] [Accepted: 06/08/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES The purpose of this study was to estimate the state of tension (tone) and the biomechanical and viscoelastic properties of skeletal muscle in aging rats during the administration of different doses of dexamethasone and to find the relationships among the state of muscle atrophy, muscle strength, and the abovementioned muscle properties. METHODS Muscle state of tension, biomechanical (elasticity, dynamic stiffness) and viscoelastic (mechanical stress relaxation time, Deborah number) properties (using MyotonPRO, Myoton Ltd, Tallinn, Estonia), lean body mass (BM), and hind limb grip strength were measured before and after the administration of a 10-day treatment with dexamethasone 100 μg/100 g BM (young and old group) and 50 μg/100 g BM (old group). RESULTS Muscle elasticity (logarithmic decrement) was lower in old animals (1.86 ± 0.03) in comparison with young adult rats (1.38 ± 0.04) (P < .01). After the 10-day treatment with dexamethasone 100 μg/100 g BM, young adult rats had 10% lower muscle elasticity (P < .01). The same dose of dexamethasone in old rats increased tone (frequency of natural oscillation) from 29.13 ± 0.51 Hz to 38.50 ± 0.95 Hz (P < .001). There were dose-dependent differences in dynamic stiffness and tone of muscle; changes in elasticity were independent of the dose in old animals. In old rats, the muscle's viscoelastic properties decreased after dexamethasone administration. Significant correlation was found between changes in muscle logarithmic decrement and stiffness (rs = 0.90; P < .05) in old animals. CONCLUSIONS Biomechanical and viscoelastic properties of skeletal muscle indicate changes in the main function of muscle during glucocorticoid-induced muscle atrophy and are in agreement with changes in hind limb strength. The myometric measurements indicate the direction and magnitude of change in muscle tissue after different doses of dexamethasone administration easily and quickly.
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Affiliation(s)
- Karin Alev
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia.
| | - Arved Vain
- Institute of Physics, Univeristy of Tartu, Tartu, Estonia
| | - Maire Aru
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Ando Pehme
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Priit Purge
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Priit Kaasik
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Teet Seene
- Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
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8
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Zhang X, Trevino MB, Wang M, Gardell SJ, Ayala JE, Han X, Kelly DP, Goodpaster BH, Vega RB, Coen PM. Impaired Mitochondrial Energetics Characterize Poor Early Recovery of Muscle Mass Following Hind Limb Unloading in Old Mice. J Gerontol A Biol Sci Med Sci 2019; 73:1313-1322. [PMID: 29562317 PMCID: PMC6132115 DOI: 10.1093/gerona/gly051] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/16/2018] [Indexed: 12/25/2022] Open
Abstract
The progression of age-related sarcopenia can be accelerated by impaired recovery of muscle mass following periods of disuse due to illness or immobilization. However, the mechanisms underlying poor recovery of aged muscle following disuse remain to be delineated. Recent evidence suggests that mitochondrial energetics play an important role in regulation of muscle mass. Here, we report that 22- to 24-month-old mice with low muscle mass and low glucose clearance rate also display poor early recovery of muscle mass following 10 days of hind limb unloading. We used unbiased and targeted approaches to identify changes in energy metabolism gene expression, metabolite pools and mitochondrial phenotype, and show for the first time that persistent mitochondrial dysfunction, dysregulated fatty acid β-oxidation, and elevated H2O2 emission occur concomitantly with poor early recovery of muscle mass following a period of disuse in old mice. Importantly, this is linked to more severe whole-body insulin resistance, as determined by insulin tolerance test. The findings suggest that muscle fuel metabolism and mitochondrial energetics could be a focus for mining therapeutic targets to improve recovery of muscle mass following periods of disuse in older animals.
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Affiliation(s)
- Xiaolei Zhang
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando
| | - Michelle B Trevino
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Miao Wang
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Stephen J Gardell
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Julio E Ayala
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Xianlin Han
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Daniel P Kelly
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Bret H Goodpaster
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando.,Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Rick B Vega
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
| | - Paul M Coen
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando.,Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida
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9
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Abstract
Skeletal muscle atrophy is a common side effect of most human diseases. Muscle loss is not only detrimental for the quality of life but it also dramatically impairs physiological processes of the organism and decreases the efficiency of medical treatments. While hypothesized for years, the existence of an atrophying programme common to all pathologies is still incompletely solved despite the discovery of several actors and key regulators of muscle atrophy. More than a decade ago, the discovery of a set of genes, whose expression at the mRNA levels were similarly altered in different catabolic situations, opened the way of a new concept: the presence of atrogenes, i.e. atrophy-related genes. Importantly, the atrogenes are referred as such on the basis of their mRNA content in atrophying muscles, the regulation at the protein level being sometimes more complicate to elucidate. It should be noticed that the atrogenes are markers of atrophy and that their implication as active inducers of atrophy is still an open question for most of them. While the atrogene family has grown over the years, it has mostly been incremented based on data coming from rodent models. Whether the rodent atrogenes are valid for humans still remain to be established. An "atrogene" was originally defined as a gene systematically up- or down-regulated in several catabolic situations. Even if recent works often restrict this notion to the up-regulation of a limited number of proteolytic enzymes, it is important to keep in mind the big picture view. In this review, we provide an update of the validated and potential rodent atrogenes and the metabolic pathways they belong, and based on recent work, their relevance in human physio-pathological situations. We also propose a more precise definition of the atrogenes that integrates rapid recovery when catabolic stimuli are stopped or replaced by anabolic ones.
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Affiliation(s)
- Daniel Taillandier
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000, Clermont-Ferrand, France.
| | - Cécile Polge
- Université Clermont Auvergne, INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, F-63000, Clermont-Ferrand, France
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10
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Le Bacquer O, Combe K, Patrac V, Ingram B, Combaret L, Dardevet D, Montaurier C, Salles J, Giraudet C, Guillet C, Sonenberg N, Boirie Y, Walrand S. 4E-BP1 and 4E-BP2 double knockout mice are protected from aging-associated sarcopenia. J Cachexia Sarcopenia Muscle 2019; 10:696-709. [PMID: 30927336 PMCID: PMC6596930 DOI: 10.1002/jcsm.12412] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/04/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Sarcopenia is the loss of muscle mass/function that occurs during the aging process. The links between mechanistic target of rapamycin (mTOR) activity and muscle development are largely documented, but the role of its downstream targets in the development of sarcopenia is poorly understood. Eukaryotic initiation factor 4E-binding proteins (4E-BPs) are targets of mTOR that repress mRNA translation initiation and are involved in the control of several physiological processes. However, their role in skeletal muscle is still poorly understood. The goal of this study was to assess how loss of 4E-BP1 and 4E-BP2 expression impacts skeletal muscle function and homeostasis in aged mice and to characterize the associated metabolic changes by metabolomic and lipidomic profiling. METHODS Twenty-four-month-old wild-type and whole body 4E-BP1/4E-BP2 double knockout (DKO) mice were used to measure muscle mass and function. Protein homeostasis was measured ex vivo in extensor digitorum longus by incorporation of l-[U-14 C]phenylalanine, and metabolomic and lipidomic profiling of skeletal muscle was performed by Metabolon, Inc. RESULTS The 4E-BP1/2 DKO mice exhibited an increase in muscle mass that was associated with increased grip strength (P < 0.05). Protein synthesis was higher under both basal (+102%, P < 0.05) and stimulated conditions (+65%, P < 0.05) in DKO skeletal muscle. Metabolomic and complex lipid analysis of skeletal muscle revealed robust differences pertaining to amino acid homeostasis, carbohydrate abundance, and certain aspects of lipid metabolism. In particular, levels of most free amino acids were lower within the 4E-BP1/2 DKO muscle. Interestingly, although glucose levels were unchanged, differences were observed in the isobaric compound maltitol/lactitol (33-fold increase, P < 0.01) and in several additional carbohydrate compounds. 4E-BP1/2 depletion also resulted in accumulation of medium-chain acylcarnitines and a 20% lower C2/C0 acylcarnitine ratio (P < 0.01) indicative of reduced β-oxidation. CONCLUSIONS Taken together, these findings demonstrate that deletion of 4E-BPs is associated with perturbed energy metabolism in skeletal muscle and could have beneficial effects on skeletal muscle mass and function in aging mice. They also identify 4E-BPs as potential targets for the treatment of sarcopenia.
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Affiliation(s)
- Olivier Le Bacquer
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Kristell Combe
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Véronique Patrac
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | | | - Lydie Combaret
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Dominique Dardevet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christophe Montaurier
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Jérôme Salles
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christophe Giraudet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Christelle Guillet
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - Yves Boirie
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France.,CHU Clermont-Ferrand, Service Nutrition Clinique, Clermont-Ferrand, France
| | - Stéphane Walrand
- INRA, UMR1019, Université Clermont Auvergne, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Clermont-Ferrand, France
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11
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Lee MK, Choi JW, Choi YH, Nam TJ. Pyropia yezoensis Protein Prevents Dexamethasone-Induced Myotube Atrophy in C2C12 Myotubes. Mar Drugs 2018; 16:md16120497. [PMID: 30544821 PMCID: PMC6316211 DOI: 10.3390/md16120497] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/28/2018] [Accepted: 12/06/2018] [Indexed: 12/21/2022] Open
Abstract
Glucocorticoids (GCs), which are endocrine hormones released under stress conditions, can cause skeletal muscle atrophy. This study investigated whether Pyropia yezoensis crude protein (PYCP) inhibits synthetic GCs dexamethasone (DEX)-induced myotube atrophy associated with proteolytic systems. Mouse skeletal muscle C2C12 myotubes were treated with DEX in the presence or absence of PYCP. DEX exposure (100 μM) for 24 h significantly decreased myotube diameter and myogenin expression, which were all increased by treatment with 20 and 40 μg/mL PYCP. Additionally, PYCP significantly reduced the nuclear expression of the forkhead box transcription factors, FoxO1 and FoxO3a, and ubiquitin-proteasome pathway activation. Further mechanistic research revealed that PYCP inhibited the autophagy-lysosome pathway in DEX-induced C2C12 myotubes. These findings indicate that PYCP prevents DEX-induced myotube atrophy through the regulation of FoxO transcription factors, followed by the inhibition of the ubiquitin-proteasome and autophagy-lysosome pathways. Therefore, we suggest that inhibiting these two proteolytic processes with FoxO transcription factors is a promising strategy for preventing DEX-related myotube atrophy.
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Affiliation(s)
- Min-Kyeong Lee
- Institute of Fisheries Sciences, Pukyong National University, Busan 46041, Korea.
| | - Jeong-Wook Choi
- Institute of Fisheries Sciences, Pukyong National University, Busan 46041, Korea.
| | - Youn Hee Choi
- Institute of Fisheries Sciences, Pukyong National University, Busan 46041, Korea.
- Department of Marine Bio-Materials & Aquaculture, Pukyong National University, Busan 48513, Korea.
| | - Taek-Jeong Nam
- Institute of Fisheries Sciences, Pukyong National University, Busan 46041, Korea.
- Department of Food Science and Nutrition, Pukyong National University, Busan 48513, Korea.
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12
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Pyropia yezoensis Protein Supplementation Prevents Dexamethasone-Induced Muscle Atrophy in C57BL/6 Mice. Mar Drugs 2018; 16:md16090328. [PMID: 30208614 PMCID: PMC6163250 DOI: 10.3390/md16090328] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/05/2018] [Accepted: 09/09/2018] [Indexed: 12/29/2022] Open
Abstract
We investigated the protective effects of Pyropia yezoensis crude protein (PYCP) against dexamethasone (DEX)-induced myotube atrophy and its underlying mechanisms. DEX (3 mg/kg body weight, intraperitoneal injection) and PYCP (150 and 300 mg/kg body weight, oral) were administrated to mice for 18 days, and the effects of PYCP on DEX-induced muscle atrophy were evaluated. Body weight, calf thickness, and gastrocnemius and tibialis anterior muscle weight were significantly decreased by DEX administration (p < 0.05), while PYCP supplementation effectively prevented the DEX-induced decrease in body weight, calf thickness, and muscle weight. PYCP supplementation also attenuated the DEX-induced increase in serum glucose, creatine kinase, and lactate dehydrogenase levels. Additionally, PYCP supplementation reversed DEX-induced muscle atrophy via the regulation of the insulin-like growth factor-I/protein kinase B/rapamycin-sensitive mTOR complex I/forkhead box O signaling pathway. The mechanistic investigation revealed that PYCP inhibited the ubiquitin-proteasome and autophagy-lysosome pathways in DEX-administrated C57BL/6 mice. These findings demonstrated that PYCP increased protein synthesis and decreased protein breakdown to prevent muscle atrophy. Therefore, PYCP supplementation appears to be useful for preventing muscle atrophy.
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13
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Harvey I, Stephenson EJ, Redd JR, Tran QT, Hochberg I, Qi N, Bridges D. Glucocorticoid-Induced Metabolic Disturbances Are Exacerbated in Obese Male Mice. Endocrinology 2018; 159:2275-2287. [PMID: 29659785 PMCID: PMC5946848 DOI: 10.1210/en.2018-00147] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/05/2018] [Indexed: 12/16/2022]
Abstract
The purpose of this study was to determine the effects of glucocorticoid-induced metabolic dysfunction in the presence of diet-induced obesity. C57BL/6J adult male lean and diet-induced obese mice were given dexamethasone, and levels of hepatic steatosis, insulin resistance, and lipolysis were determined. Obese mice given dexamethasone had significant, synergistic effects on fasting glucose, insulin resistance, and markers of lipolysis, as well as hepatic steatosis. This was associated with synergistic transactivation of the lipolytic enzyme adipose triglyceride lipase. The combination of chronically elevated glucocorticoids and obesity leads to exacerbations in metabolic dysfunction. Our findings suggest lipolysis may be a key player in glucocorticoid-induced insulin resistance and fatty liver in individuals with obesity.
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Affiliation(s)
- Innocence Harvey
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Erin J Stephenson
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - JeAnna R Redd
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Quynh T Tran
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Irit Hochberg
- Institute of Endocrinology, Diabetes and Metabolism, Rambam Health Care Campus, Haifa, Israel
| | - Nathan Qi
- Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, Michigan
| | - Dave Bridges
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
- Correspondence: Dave Bridges, PhD, Department of Nutritional Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, Michigan 48109. E-mail:
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14
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Oliva J. Proteasome and Organs Ischemia-Reperfusion Injury. Int J Mol Sci 2017; 19:ijms19010106. [PMID: 29301204 PMCID: PMC5796056 DOI: 10.3390/ijms19010106] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 12/12/2017] [Accepted: 12/27/2017] [Indexed: 12/17/2022] Open
Abstract
The treatment of organ failure on patients requires the transplantation of functional organs, from donors. Over time, the methodology of transplantation was improved by the development of organ preservation solutions. The storage of organs in preservation solutions is followed by the ischemia of the organ, resulting in a shortage of oxygen and nutrients, which damage the tissues. When the organ is ready for the transplantation, the reperfusion of the organ induces an increase of the oxidative stress, endoplasmic reticulum stress, and inflammation which causes tissue damage, resulting in a decrease of the transplantation success. However, the addition of proteasome inhibitor in the preservation solution alleviated the injuries due to the ischemia-reperfusion process. The proteasome is a protein structure involved in the regulation the inflammation and the clearance of damaged proteins. The goal of this review is to summarize the role of the proteasome and pharmacological compounds that regulate the proteasome in protecting the organs from the ischemia-reperfusion injury.
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Affiliation(s)
- Joan Oliva
- Department of Medicine, LA BioMed at Harbor UCLA Medical Center, Torrance, CA 90502, USA.
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15
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Physiology of ageing of the musculoskeletal system. Best Pract Res Clin Rheumatol 2017; 31:203-217. [PMID: 29224697 DOI: 10.1016/j.berh.2017.09.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 09/07/2017] [Indexed: 02/06/2023]
Abstract
This review aims to provide a summary of current concepts of ageing in relation to the musculoskeletal system, highlighting recent advances in the understanding of the mechanisms involved in the development of age-related changes in bone, skeletal muscle, chondroid and fibrous tissues. The key components of the musculoskeletal system and their functions are introduced together with a general overview of the molecular hallmarks of ageing. A brief description of the normal architecture of each of these tissue types is followed by a summary of established and developing concepts of mechanisms contributing to the age-related alterations in each. Extensive detailed description of these changes is beyond the scope of this review; instead, we aim to highlight some of the most significant processes and, where possible, the molecular changes underlying these and refer the reader to in-depth, subspecialist reviews of the individual components for further details.
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16
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Singh AK, Shree S, Chattopadhyay S, Kumar S, Gurjar A, Kushwaha S, Kumar H, Trivedi AK, Chattopadhyay N, Maurya R, Ramachandran R, Sanyal S. Small molecule adiponectin receptor agonist GTDF protects against skeletal muscle atrophy. Mol Cell Endocrinol 2017; 439:273-285. [PMID: 27645900 DOI: 10.1016/j.mce.2016.09.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 08/23/2016] [Accepted: 09/14/2016] [Indexed: 02/02/2023]
Abstract
Skeletal muscle atrophy is a debilitating response to several major diseases, muscle disuse and chronic steroid treatment for which currently no therapy is available. Since adiponectin signaling plays key roles in muscle energetics, we assessed if globular adiponectin (gAd) or the small molecule adiponectin mimetic 6-C-β-D-glucopyranosyl-(2S,3S)-(+)-5,7,3',4'-tetrahydroxydihydroflavonol (GTDF) could ameliorate muscle atrophy. Both GTDF and gAd induced C2C12 myoblast differentiation. GTDF and gAd effectively prevented reduction in myotube area and suppressed the expressions of atrophy markers; atrogin-1 and muscle ring finger protein-1 (MuRF1) in models of steroid, cytokine and starvation -induced muscle atrophy. The protective effects of GTDF and gAd were routed through AMPK and AKT activation and thereby stimulation of PPAR gamma coactivator 1α and inhibition of forkhead box O transcription factors. Finally, GTDF and gAd mitigated dexamethasone-induced muscle atrophy in vivo. Together, our results demonstrate that activating adiponectin signaling may be an effective therapeutic strategy against skeletal muscle atrophy.
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Affiliation(s)
- Abhishek Kumar Singh
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Sonal Shree
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Sourav Chattopadhyay
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India; Academy of Scientific and Innovative Research (AcSIR), CSIR- Central Drug Research Institute Campus, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Sudhir Kumar
- Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Anagha Gurjar
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India; Academy of Scientific and Innovative Research (AcSIR), CSIR- Central Drug Research Institute Campus, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Sapana Kushwaha
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Harish Kumar
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Arun Kumar Trivedi
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Naibedya Chattopadhyay
- Division of Endocrinology, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Rakesh Maurya
- Division of Medicinal and Process Chemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Ravishankar Ramachandran
- Division of Molecular and Structural Biology, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India
| | - Sabyasachi Sanyal
- Division of Biochemistry, CSIR-Central Drug Research Institute, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India; Academy of Scientific and Innovative Research (AcSIR), CSIR- Central Drug Research Institute Campus, 10, Janakipuram Extn, Sitapur Road, Lucknow 226031, India.
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Deval C, Capel F, Laillet B, Polge C, Béchet D, Taillandier D, Attaix D, Combaret L. Docosahexaenoic acid-supplementation prior to fasting prevents muscle atrophy in mice. J Cachexia Sarcopenia Muscle 2016; 7:587-603. [PMID: 27239420 PMCID: PMC4864105 DOI: 10.1002/jcsm.12103] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 11/13/2015] [Accepted: 01/11/2016] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Muscle wasting prevails in numerous diseases (e.g. diabetes, cardiovascular and kidney diseases, COPD,…) and increases healthcare costs. A major clinical issue is to devise new strategies preventing muscle wasting. We hypothesized that 8-week docosahexaenoic acid (DHA) supplementation prior to fasting may preserve muscle mass in vivo. METHODS Six-week-old C57BL/6 mice were fed a DHA-enriched or a control diet for 8 weeks and then fasted for 48 h. RESULTS Feeding mice a DHA-enriched diet prior to fasting elevated muscle glycogen contents, reduced muscle wasting, blocked the 55% decrease in Akt phosphorylation, and reduced by 30-40% the activation of AMPK, ubiquitination, or autophagy. The DHA-enriched diet fully abolished the fasting induced-messenger RNA (mRNA) over-expression of the endocannabinoid receptor-1. Finally, DHA prevented or modulated the fasting-dependent increase in muscle mRNA levels for Rab18, PLD1, and perilipins, which determine the formation and fate of lipid droplets, in parallel with muscle sparing. CONCLUSIONS These data suggest that 8-week DHA supplementation increased energy stores that can be efficiently mobilized, and thus preserved muscle mass in response to fasting through the regulation of Akt- and AMPK-dependent signalling pathways for reducing proteolysis activation. Whether a nutritional strategy aiming at increasing energy status may shorten recovery periods in clinical settings remains to be tested.
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Affiliation(s)
- Christiane Deval
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Frédéric Capel
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Brigitte Laillet
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Cécile Polge
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Daniel Béchet
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Daniel Taillandier
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Didier Attaix
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
| | - Lydie Combaret
- INRA, UMR 1019 UNH, CRNHF-63000 Auvergne Clermont-Ferrand France; Clermont Université, Université d'Auvergne Unité de Nutrition Humaine BP 10448 F-63000 Clermont-Ferrand France
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Role of Myofibrillar Protein Catabolism in Development of Glucocorticoid Myopathy: Aging and Functional Activity Aspects. Metabolites 2016; 6:metabo6020015. [PMID: 27187487 PMCID: PMC4931546 DOI: 10.3390/metabo6020015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/03/2016] [Accepted: 05/10/2016] [Indexed: 11/17/2022] Open
Abstract
Muscle weakness in corticosteroid myopathy is mainly the result of the destruction and atrophy of the myofibrillar compartment of fast-twitch muscle fibers. Decrease of titin and myosin, and the ratio of nebulin and MyHC in myopathic muscle, shows that these changes of contractile and elastic proteins are the result of increased catabolism of the abovementioned proteins in skeletal muscle. Slow regeneration of skeletal muscle is in good correlation with a decreased number of satellite cells under the basal lamina of muscle fibers. Aging causes a reduction of AMP-activated protein kinase (AMPK) activity as the result of the reduced function of the mitochondrial compartment. AMPK activity increases as a result of increased functional activity. Resistance exercise causes anabolic and anticatabolic effects in skeletal muscle: muscle fibers experience hypertrophy while higher myofibrillar proteins turn over. These changes are leading to the qualitative remodeling of muscle fibers. As a result of these changes, possible maximal muscle strength is increasing. Endurance exercise improves capillary blood supply, increases mitochondrial biogenesis and muscle oxidative capacity, and causes a faster turnover rate of sarcoplasmic proteins as well as qualitative remodeling of type I and IIA muscle fibers. The combination of resistance and endurance exercise may be the fastest way to prevent or decelerate muscle atrophy due to the anabolic and anticatabolic effects of exercise combined with an increase in oxidative capacity. The aim of the present short review is to assess the role of myofibrillar protein catabolism in the development of glucocorticoid-caused myopathy from aging and physical activity aspects.
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Hochberg I, Harvey I, Tran QT, Stephenson EJ, Barkan AL, Saltiel AR, Chandler WF, Bridges D. Gene expression changes in subcutaneous adipose tissue due to Cushing's disease. J Mol Endocrinol 2015; 55:81-94. [PMID: 26150553 PMCID: PMC4543687 DOI: 10.1530/jme-15-0119] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/06/2015] [Indexed: 01/15/2023]
Abstract
Glucocorticoids have major effects on adipose tissue metabolism. To study tissue mRNA expression changes induced by chronic elevated endogenous glucocorticoids, we performed RNA sequencing on the subcutaneous adipose tissue from patients with Cushing's disease (n=5) compared to patients with nonfunctioning pituitary adenomas (n=11). We found a higher expression of transcripts involved in several metabolic pathways, including lipogenesis, proteolysis and glucose oxidation as well as a decreased expression of transcripts involved in inflammation and protein synthesis. To further study this in a model system, we subjected mice to dexamethasone treatment for 12 weeks and analyzed their inguinal (subcutaneous) fat pads, which led to similar findings. Additionally, mice treated with dexamethasone showed drastic decreases in lean body mass as well as increased fat mass, further supporting the human transcriptomic data. These data provide insight to transcriptional changes that may be responsible for the comorbidities associated with chronic elevations of glucocorticoids.
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Affiliation(s)
- Irit Hochberg
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Innocence Harvey
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Quynh T Tran
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Erin J Stephenson
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Ariel L Barkan
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Alan R Saltiel
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - William F Chandler
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
| | - Dave Bridges
- Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA Institute of EndocrinologyDiabetes and Metabolism, Rambam Health Care Campus, Haifa, IsraelLife Science InstituteUniversity of Michigan, Ann Arbor, MI, USAPhysiologyUTHSC, Memphis, TN, USAPreventive MedicineUTHSC, Memphis, TN, USAInternal MedicineUniversity of Michigan, Ann Arbor, MI USANeurosurgeryUniversity of Michigan, Ann Arbor, MI USAPediatricsUTHSC, Memphis, TN, USA
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20
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Polge C, Attaix D, Taillandier D. Role of E2-Ub-conjugating enzymes during skeletal muscle atrophy. Front Physiol 2015; 6:59. [PMID: 25805999 PMCID: PMC4354305 DOI: 10.3389/fphys.2015.00059] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 02/14/2015] [Indexed: 01/05/2023] Open
Abstract
The Ubiquitin Proteasome System (UPS) is a major actor of muscle wasting during various physio-pathological situations. In the past 15 years, increasing amounts of data have depicted a picture, although incomplete, of the mechanisms implicated in myofibrillar protein degradation, from the discovery of muscle-specific E3 ligases to the identification of the signaling pathways involved. The targeting specificity of the UPS relies on the capacity of the system to first recognize and then label the proteins to be degraded with a poly-ubiquitin (Ub) chain. It is fairly assumed that the recognition of the substrate is accomplished by the numerous E3 ligases present in mammalian cells. However, most E3s do not possess any catalytic activity and E2 enzymes may be more than simple Ub-providers for E3s since they are probably important actors in the ubiquitination machinery. Surprisingly, most authors have tried to characterize E3 substrates, but the exact role of E2s in muscle protein degradation is largely unknown. A very limited number of the 35 E2s described in humans have been studied in muscle protein breakdown experiments and the vast majority of studies were only descriptive. We review here the role of E2 enzymes in skeletal muscle and the difficulties linked to their study and provide future directions for the identification of muscle E2s responsible for the ubiquitination of contractile proteins.
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Affiliation(s)
- Cecile Polge
- UMR 1019 Nutrition Humaine, Institut National de la Recherche Agronomique Saint Genès Champanelle, France
| | - Didier Attaix
- UMR 1019 Nutrition Humaine, Institut National de la Recherche Agronomique Saint Genès Champanelle, France
| | - Daniel Taillandier
- UMR 1019 Nutrition Humaine, Institut National de la Recherche Agronomique Saint Genès Champanelle, France
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21
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White JR, Confides AL, Moore-Reed S, Hoch JM, Dupont-Versteegden EE. Regrowth after skeletal muscle atrophy is impaired in aged rats, despite similar responses in signaling pathways. Exp Gerontol 2015; 64:17-32. [PMID: 25681639 DOI: 10.1016/j.exger.2015.02.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/14/2015] [Accepted: 02/10/2015] [Indexed: 01/07/2023]
Abstract
Skeletal muscle regrowth after atrophy is impaired in the aged and in this study we hypothesized that this can be explained by a blunted response of signaling pathways and cellular processes during reloading after hind limb suspension in muscles from old rats. Male Brown Norway Fisher 344 rats at 6 (young) and 32 (old) months of age were subjected to normal ambulatory conditions (amb), hind limb suspension for 14 days (HS), and HS followed by reloading through normal ambulation for 14 days (RE); soleus muscles were used for analysis of intracellular signaling pathways and cellular processes. Soleus muscle regrowth was blunted in old compared to young rats which coincided with a recovery of serum IGF-1 and IGFBP-3 levels in young but not old. However, the response to reloading for p-Akt, p-p70s6k and p-GSK3β protein abundance was similar between muscles from young and old rats, even though main effects for age indicate an increase in activation of this protein synthesis pathway in the aged. Similarly, MAFbx mRNA levels in soleus muscle from old rats recovered to the same extent as in the young, while Murf-1 was unchanged. mRNA abundance of autophagy markers Atg5 and Atg7 showed an identical response in muscle from old compared to young rats, but beclin did not. Autophagic flux was not changed at either age at the measured time point. Apoptosis was elevated in soleus muscle from old rats particularly with HS, but recovered in HSRE and these changes were not associated with differences in caspase-3, -8 or -9 activity in any group. Protein abundance of apoptosis repressor with caspase-recruitment domain (ARC), cytosolic EndoG, as well as cytosolic and nuclear apoptosis inducing factor (AIF) were lower in muscle from old rats, and there was no age-related difference in the response to atrophy or regrowth. Soleus muscles from old rats had a higher number of ED2 positive macrophages in all groups and these decreased with HS, but recovered in HSRE in the old, while no changes were observed in the young. Pro-inflammatory cytokines in serum did not show a differential response with age to different loading conditions. Results indicate that at the measured time point the impaired skeletal muscle regrowth after atrophy in aged animals is not associated with a general lack of responsiveness to changes in loading conditions.
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Affiliation(s)
- Jena R White
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536-0200, USA
| | - Amy L Confides
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536-0200, USA
| | - Stephanie Moore-Reed
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536-0200, USA
| | - Johanna M Hoch
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536-0200, USA
| | - Esther E Dupont-Versteegden
- Department of Rehabilitation Sciences, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536-0200, USA.
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22
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Altamirano F, Perez CF, Liu M, Widrick J, Barton ER, Allen PD, Adams JA, Lopez JR. Whole body periodic acceleration is an effective therapy to ameliorate muscular dystrophy in mdx mice. PLoS One 2014; 9:e106590. [PMID: 25181488 PMCID: PMC4152333 DOI: 10.1371/journal.pone.0106590] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/30/2014] [Indexed: 12/29/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a genetic disorder caused by the absence of dystrophin in both skeletal and cardiac muscles. This leads to severe muscle degeneration, and dilated cardiomyopathy that produces patient death, which in most cases occurs before the end of the second decade. Several lines of evidence have shown that modulators of nitric oxide (NO) pathway can improve skeletal muscle and cardiac function in the mdx mouse, a mouse model for DMD. Whole body periodic acceleration (pGz) is produced by applying sinusoidal motion to supine humans and in standing conscious rodents in a headward-footward direction using a motion platform. It adds small pulses as a function of movement frequency to the circulation thereby increasing pulsatile shear stress to the vascular endothelium, which in turn increases production of NO. In this study, we examined the potential therapeutic properties of pGz for the treatment of skeletal muscle pathology observed in the mdx mouse. We found that pGz (480 cpm, 8 days, 1 hr per day) decreased intracellular Ca2+ and Na+ overload, diminished serum levels of creatine kinase (CK) and reduced intracellular accumulation of Evans Blue. Furthermore, pGz increased muscle force generation and expression of both utrophin and the carboxy-terminal PDZ ligand of nNOS (CAPON). Likewise, pGz (120 cpm, 12 h) applied in vitro to skeletal muscle myotubes reduced Ca2+ and Na+ overload, diminished abnormal sarcolemmal Ca2+ entry and increased phosphorylation of endothelial NOS. Overall, this study provides new insights into the potential therapeutic efficacy of pGz as a non-invasive and non-pharmacological approach for the treatment of DMD patients through activation of the NO pathway.
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Affiliation(s)
- Francisco Altamirano
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Claudio F. Perez
- Department of Anesthesiology Perioperative and Pain Medicine, Brigham & Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Min Liu
- Department of Physiology, Perleman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jeffrey Widrick
- Division of Genetics and Program in Genomics, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Elisabeth R. Barton
- Anatomy and Cell Biology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Paul D. Allen
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- Department of Anesthesiology Perioperative and Pain Medicine, Brigham & Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jose A. Adams
- Division of Neonatology, Mount Sinai Medical Center, Miami, Florida, United States of America
| | - Jose R. Lopez
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America
- Department of Anesthesiology Perioperative and Pain Medicine, Brigham & Women’s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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23
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Wollersheim T, Woehlecke J, Krebs M, Hamati J, Lodka D, Luther-Schroeder A, Langhans C, Haas K, Radtke T, Kleber C, Spies C, Labeit S, Schuelke M, Spuler S, Spranger J, Weber-Carstens S, Fielitz J. Dynamics of myosin degradation in intensive care unit-acquired weakness during severe critical illness. Intensive Care Med 2014; 40:528-38. [PMID: 24531339 DOI: 10.1007/s00134-014-3224-9] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 01/18/2014] [Indexed: 01/31/2023]
Abstract
IMPORTANCE Intensive care unit (ICU)-acquired muscle wasting is a devastating complication leading to persistent weakness and functional disability. The mechanisms of this myopathy are unclear, but a disturbed balance of myosin heavy chain (MyHC) is implicated. OBJECTIVE To investigate pathways of myosin turnover in severe critically ill patients at high risk of ICU-acquired weakness. DESIGN Prospective, mechanistic, observational study. SETTING Interdisciplinary ICUs of a university hospital. PARTICIPANTS Twenty-nine patients with Sequential Organ Failure Assessment (SOFA) scores of at least 8 on three consecutive days within the first 5 days in ICU underwent two consecutive open skeletal muscle biopsies from the vastus lateralis at median days 5 and 15. Control biopsy specimens were from healthy subjects undergoing hip-replacement surgery. INTERVENTIONS None. MAIN OUTCOME(S) AND MEASURE(S) Time-dependent changes in myofiber architecture, MyHC synthesis, and degradation were determined and correlated with clinical data. RESULTS ICU-acquired muscle wasting was characterized by early, disrupted myofiber ultrastructure followed by atrophy of slow- and fast-twitch myofibers at later time points. A rapid decrease in MyHC mRNA and protein expression occurred by day 5 and persisted at day 15 (P < 0.05). Expression of the atrophy genes MuRF-1 and Atrogin1 was increased at day 5 (P < 0.05). Early MuRF-1 protein content was closely associated with late myofiber atrophy and the severity of weakness. CONCLUSIONS AND RELEVANCE Decreased synthesis and increased degradation of MyHCs contribute to ICU-acquired muscle wasting. The rates and time frames suggest that pathogenesis of muscle failure is initiated very early during critical illness. The persisting reduction of MyHC suggests that sustained treatment is required.
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Affiliation(s)
- Tobias Wollersheim
- Anesthesiology and Operative Intensive Care Medicine, Charité-Universitätsmedizin Berlin, Campus Virchow and Campus Mitte, Berlin, Germany
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24
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Demontis F, Piccirillo R, Goldberg AL, Perrimon N. Mechanisms of skeletal muscle aging: insights from Drosophila and mammalian models. Dis Model Mech 2013; 6:1339-52. [PMID: 24092876 PMCID: PMC3820258 DOI: 10.1242/dmm.012559] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
A characteristic feature of aged humans and other mammals is the debilitating, progressive loss of skeletal muscle function and mass that is known as sarcopenia. Age-related muscle dysfunction occurs to an even greater extent during the relatively short lifespan of the fruit fly Drosophila melanogaster. Studies in model organisms indicate that sarcopenia is driven by a combination of muscle tissue extrinsic and intrinsic factors, and that it fundamentally differs from the rapid atrophy of muscles observed following disuse and fasting. Extrinsic changes in innervation, stem cell function and endocrine regulation of muscle homeostasis contribute to muscle aging. In addition, organelle dysfunction and compromised protein homeostasis are among the primary intrinsic causes. Some of these age-related changes can in turn contribute to the induction of compensatory stress responses that have a protective role during muscle aging. In this Review, we outline how studies in Drosophila and mammalian model organisms can each provide distinct advantages to facilitate the understanding of this complex multifactorial condition and how they can be used to identify suitable therapies.
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Affiliation(s)
- Fabio Demontis
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
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25
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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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26
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Kim CY, Kim KH. Dexamethasone-induced selenoprotein S degradation is required for adipogenesis. J Lipid Res 2013; 54:2069-2082. [PMID: 23687306 DOI: 10.1194/jlr.m034603] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Although adipogenesis is associated with induction of endoplasmic reticulum (ER) stress, the role of selenoprotein S (SEPS1), an ER resident selenoprotein known to regulate ER stress and ER-associated protein degradation, is unknown. We found an inverse relationship between SEPS1 level in adipose tissue and adiposity in mice. While SEPS1 expression was increased during adipogenesis, a markedly reduced SEPS1 protein level was found in the early phase of adipogenesis due to dexamethasone (DEX)-induced proteosomal degradation of SEPS1. Overexpression of SEPS1 in the early phase of cell differentiation resulted in impairment of adipogenesis with reduced levels of CCAAT/enhancer binding protein α and other adipocyte marker genes during the course of adipogenesis. Conversely, knockdown of SEPS1 resulted in the promotion of adipogenesis. Additionally, altered SEPS1 expression was associated with changes in expression of ER stress marker genes in the early phase of adipogenesis, and ubiquitin-proteasome system (UPS)-related ubiquitination and proteasome function. Our study reveals that SEPS1 is a novel anti-adipogenic selenoprotein that modulates ER stress- and UPS-dependent adipogenesis. Our results also identifies a novel function of DEX in the regulation of adipogenesis through induction of SEPS1 degradation. Taken together, DEX-dependent degradation of SEPS1 in the early phase of adipogenesis is necessary for initiating ER stress- and UPS-dependent maturation of adipocytes.
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Affiliation(s)
- Choon Young Kim
- Department of Food Science, Purdue University, West Lafayette, IN 47907
| | - Kee-Hong Kim
- Department of Food Science, Purdue University, West Lafayette, IN 47907.
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27
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Korzick DH, Sharda DR, Pruznak AM, Lang CH. Aging accentuates alcohol-induced decrease in protein synthesis in gastrocnemius. Am J Physiol Regul Integr Comp Physiol 2013; 304:R887-98. [PMID: 23535459 DOI: 10.1152/ajpregu.00083.2013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The present study sought to determine whether the protein catabolic response in skeletal muscle produced by chronic alcohol feeding was exaggerated in aged rats. Adult (3 mo) and aged (18 mo) female F344 rats were fed a nutritionally complete liquid diet containing alcohol (36% of total calories) or an isocaloric isonitrogenous control diet for 20 wk. Muscle (gastrocnemius) protein synthesis, as well as mTOR and proteasome activity did not differ between control-fed adult and aged rats, despite the increased TNF-α and IL-6 mRNA and decreased IGF-I mRNA in muscle of aged rats. Compared with alcohol-fed adult rats, aged rats demonstrated an exaggerated alcohol-induced reduction in lean body mass and protein synthesis (both sarcoplasmic and myofibrillar) in gastrocnemius. Alcohol-fed aged rats had enhanced dephosphorylation of 4E-BP1, as well as enhanced binding of raptor with both mTOR and Deptor, and a decreased binding of raptor with 4E-BP1. Alcohol feeding of both adult and aged rats reduced RagA binding to raptor. The LKB1-AMPK-REDD1 pathway was upregulated in gastrocnemius from alcohol-fed aged rats. These exaggerated alcohol-induced effects in aged rats were associated with a greater decrease in muscle but not circulating IGF-I, but no further increase in inflammatory mediators. In contrast, alcohol did not exaggerate the age-induced increase in atrogin-1 and MuRF1 mRNA or the increased proteasome activity. Our results demonstrate that, compared with adult rats, the gastrocnemius from aged rats is more sensitive to the catabolic effects of alcohol on protein synthesis, but not protein degradation, and this exaggerated response may be AMPK-dependent.
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Affiliation(s)
- Donna H Korzick
- Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
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28
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HATTORI TAKUYA, MURASE TAMAYO, IWASE ERIKA, TAKAHASHI KEIJI, OHTAKE MASAFUMI, TSUBOI KOJI, OHTAKE MAYUKO, MIYACHI MASAAKI, MUROHARA TOYOAKI, NAGATA KOHZO. Glucocorticoid-induced hypertension and cardiac injury: effects of mineralocorticoid and glucocorticoid receptor antagonism. NAGOYA JOURNAL OF MEDICAL SCIENCE 2013; 75:81-92. [PMID: 23544271 PMCID: PMC4345706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Glucocorticoids are widely administered for the treatment of various disorders, although their long-term use results in adverse effects associated with glucocorticoid excess. We investigated the pathophysiological roles of glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs) in the cardiac changes induced by exogenous corticosterone in rats. Corticosterone or vehicle was injected twice daily in rats from 8 to 12 weeks of age. The effects of the GR antagonist RU486, the MR antagonist spironolactone, or both agents on corticosterone action were also determined. Corticosterone induced hypertension, left ventricular (LV) fibrosis, and LV diastolic dysfunction. Neither RU486 nor spironolactone affected corticosterone-induced hypertension, whereas spironolactone, but not RU486, attenuated the effects of corticosterone on LV fibrosis and diastolic function. Corticosterone also increased cardiac oxidative stress and inflammation in a manner sensitive to spironolactone but not to RU486. The corticosterone-induced LV atrophy was not affected by either RU486 or spironolactone. Our results implicate MRs in the cardiac fibrosis and diastolic dysfunction, but not MRs or GRs in the cardiac atrophy, induced by corticosterone. Neither MRs nor GRs appear to contribute to corticosterone-induced hypertension.
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Affiliation(s)
- TAKUYA HATTORI
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - TAMAYO MURASE
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - ERIKA IWASE
- Department of Medical Technology, Nagoya University School of Health Sciences, Nagoya, Japan
| | - KEIJI TAKAHASHI
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - MASAFUMI OHTAKE
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - KOJI TSUBOI
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - MAYUKO OHTAKE
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - MASAAKI MIYACHI
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - TOYOAKI MUROHARA
- Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - KOHZO NAGATA
- Department of Pathophysiological Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
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29
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Grizard J, Dardevet D, Papet I, Mosoni L, Mirand PP, Attaix D, Tauveron I, Bonin D, Arnal M. Nutrient regulation of skeletal muscle protein metabolism in animals. The involvement of hormones and substrates. Nutr Res Rev 2012; 8:67-91. [PMID: 19094280 DOI: 10.1079/nrr19950007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- J Grizard
- Laboratoire d'Etude du Métabolisme Azoté, Institut National de la Recherche Agronomique, Centre de Clermont-Ferrand - Theix, Centre de Recherche en Nutrition Humaine d'Auvergne, 63122 Saint-Genès-Champanelle, France
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30
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Dardevet D, Savary-Auzeloux I, Remond D, Mosoni L, Marzetti E, Buford TW, Bernabei R, Dionne IJ, Buford TW, Marzetti E, Manini TM, Buehring B, Kirchner E, Calabrese L, Manini TM, Clark BC, Fonseca HM, Delbono O, Taylor JR, Aubertin-Leheudre M, Barbat-Artigas S, Pion CH, Thornell LE, Gustafsson T, Cederholm T, Ulfhake B. Commentaries on Viewpoint: Muscle atrophy is not always sarcopenia. J Appl Physiol (1985) 2012; 113:680-4. [PMID: 22896680 PMCID: PMC4459919 DOI: 10.1152/japplphysiol.00667.2012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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31
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Role of exercise therapy in prevention of decline in aging muscle function: glucocorticoid myopathy and unloading. J Aging Res 2012; 2012:172492. [PMID: 22778959 PMCID: PMC3385633 DOI: 10.1155/2012/172492] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 05/14/2012] [Indexed: 01/05/2023] Open
Abstract
Changes in skeletal muscle quantity and quality lead to disability in the aging population. Physiological changes in aging skeletal muscle are associated with a decline in mass, strength, and inability to maintain balance. Glucocorticoids, which are in wide exploitation in various clinical scenarios, lead to the loss of the myofibrillar apparatus, changes in the extracellular matrix, and a decrease in muscle strength and motor activity, particularly in the elderly. Exercise therapy has shown to be a useful tool for the prevention of different diseases, including glucocorticoid myopathy and muscle unloading in the elderly. The purpose of the paper is to discuss the possibilities of using exercise therapy in the prevention of glucocorticoid caused myopathy and unloading in the elderly and to describe relationships between the muscle contractile apparatus and the extracellular matrix in different types of aging muscles.
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32
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Seene T, Kaasik P, Riso EM. Review on aging, unloading and reloading: Changes in skeletal muscle quantity and quality. Arch Gerontol Geriatr 2012; 54:374-80. [DOI: 10.1016/j.archger.2011.05.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 05/04/2011] [Accepted: 05/05/2011] [Indexed: 11/29/2022]
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33
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Magne H, Savary-Auzeloux I, Migné C, Peyron MA, Combaret L, Rémond D, Dardevet D. Contrarily to whey and high protein diets, dietary free leucine supplementation cannot reverse the lack of recovery of muscle mass after prolonged immobilization during ageing. J Physiol 2012; 590:2035-49. [PMID: 22351629 DOI: 10.1113/jphysiol.2011.226266] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During ageing, immobilization periods increase and are partially responsible of sarcopaenia by inducing a muscle atrophy which is hardly recovered from. Immobilization-induced atrophy is due to an increase of muscle apoptotic and proteolytic processes and decreased protein synthesis. Moreover, previous data suggested that the lack of muscle mass recovery might be due to a defect in protein synthesis response during rehabilitation. This study was conducted to explore protein synthesis during reloading and leucine supplementation effect as a nutritional strategy for muscle recovery. Old rats (22–24 months old) were subjected to unilateral hindlimb casting for 8 days (I8) and allowed to recover for 10–40 days (R10–R40). They were fed a casein (±leucine) diet during the recovery. Immobilized gastrocnemius muscles atrophied by 20%, and did not recover even at R40. Amount of polyubiquitinated conjugates and chymotrypsin- and trypsin-like activities of the 26S proteasome increased. These changes paralleled an ‘anabolic resistance' of the protein synthesis at the postprandial state (decrease of protein synthesis, P-S6 and P-4E-BP1). During the recovery, proteasome activities remained elevated until R10 before complete normalization and protein synthesis was slightly increased. With free leucine supplementation during recovery, if proteasome activities were normalized earlier and protein synthesis was higher during the whole recovery, it nevertheless failed in muscle mass gain. This discrepancy could be due to a ‘desynchronization' between the leucine signal and the availability of amino acids coming from casein digestion. Thus, when supplemented with leucine-rich proteins (i.e. whey) and high protein diets, animals partially recovered the muscle mass loss.
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Affiliation(s)
- Hugues Magne
- Clermont Université, Université d’Auvergne,Unité de Nutrition Humaine, BP 10448, F-63000 Clermont-Ferrand, France
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Sakuma K, Yamaguchi A. Sarcopenia and age-related endocrine function. Int J Endocrinol 2012; 2012:127362. [PMID: 22690213 PMCID: PMC3368374 DOI: 10.1155/2012/127362] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 02/22/2012] [Indexed: 02/06/2023] Open
Abstract
Sarcopenia, the age-related loss of skeletal muscle, is characterized by a deterioration of muscle quantity and quality leading to a gradual slowing of movement, a decline in strength and power, and an increased risk of fall-related injuries. Since sarcopenia is largely attributed to various molecular mediators affecting fiber size, mitochondrial homeostasis, and apoptosis, numerous targets exist for drug discovery. In this paper, we summarize the current understanding of the endocrine contribution to sarcopenia and provide an update on hormonal intervention to try to improve endocrine defects. Myostatin inhibition seems to be the most interesting strategy for attenuating sarcopenia other than resistance training with amino acid supplementation. Testosterone supplementation in large amounts and at low frequency improves muscle defects with aging but has several side effects. Although IGF-I is a potent regulator of muscle mass, its therapeutic use has not had a positive effect probably due to local IGF-I resistance. Treatment with ghrelin may ameliorate the muscle atrophy elicited by age-dependent decreases in growth hormone. Ghrelin is an interesting candidate because it is orally active, avoiding the need for injections. A more comprehensive knowledge of vitamin-D-related mechanisms is needed to utilize this nutrient to prevent sarcopenia.
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Affiliation(s)
- Kunihiro Sakuma
- Research Center for Physical Fitness, Sports and Health, Toyohashi University of Technology, 1-1 Hibarigaoka, Tenpaku-cho, Toyohashi 441-8580, Japan
- *Kunihiro Sakuma:
| | - Akihiko Yamaguchi
- School of Dentistry, Health Sciences University of Hokkaido, Kanazawa, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
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Chen Q, Li N, Zhu W, Li W, Tang S, Yu W, Gao T, Zhang J, Li J. Insulin alleviates degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system in septic rats. JOURNAL OF INFLAMMATION-LONDON 2011; 8:13. [PMID: 21639905 PMCID: PMC3120636 DOI: 10.1186/1476-9255-8-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 06/03/2011] [Indexed: 01/03/2023]
Abstract
Hypercatabolism is common under septic conditions. Skeletal muscle is the main target organ for hypercatabolism, and this phenomenon is a vital factor in the deterioration of recovery in septic patients. In skeletal muscle, activation of the ubiquitin-proteasome system plays an important role in hypercatabolism under septic status. Insulin is a vital anticatabolic hormone and previous evidence suggests that insulin administration inhibits various steps in the ubiquitin-proteasome system. However, whether insulin can alleviate the degradation of skeletal muscle protein by inhibiting the ubiquitin-proteasome system under septic condition is unclear. This paper confirmed that mRNA and protein levels of the ubiquitin-proteasome system were upregulated and molecular markers of skeletal muscle proteolysis (tyrosine and 3-methylhistidine) simultaneously increased in the skeletal muscle of septic rats. Septic rats were infused with insulin at a constant rate of 2.4 mU.kg-1.min-1 for 8 hours. Concentrations of mRNA and proteins of the ubiquitin-proteasome system and molecular markers of skeletal muscle proteolysis were mildly affected. When the insulin infusion dose increased to 4.8 mU.kg-1.min-1, mRNA for ubiquitin, E2-14 KDa, and the C2 subunit were all sharply downregulated. At the same time, the levels of ubiquitinated proteins, E2-14KDa, and the C2 subunit protein were significantly reduced. Tyrosine and 3-methylhistidine decreased significantly. We concluded that the ubiquitin-proteasome system is important skeletal muscle hypercatabolism in septic rats. Infusion of insulin can reverse the detrimental metabolism of skeletal muscle by inhibiting the ubiquitin-proteasome system, and the effect is proportional to the insulin infusion dose.
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Affiliation(s)
- Qiyi Chen
- Department of General Surgery, Jinling Hospital, Medical College of Nanjing University, Nanjing 210002, Jiangsu Province, China.
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Olanow CW, McNaught K. Parkinson's disease, proteins, and prions: Milestones. Mov Disord 2011; 26:1056-71. [DOI: 10.1002/mds.23767] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Mizunoya W, Upadhaya R, Burczynski FJ, Wang G, Anderson JE. Nitric oxide donors improve prednisone effects on muscular dystrophy in the mdx mouse diaphragm. Am J Physiol Cell Physiol 2011; 300:C1065-77. [PMID: 21270295 DOI: 10.1152/ajpcell.00482.2010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In Duchenne muscular dystrophy (DMD), palliative glucocorticoid therapy can produce myopathy or calcification. Since increased nitric oxide synthase activity in dystrophic mice promotes regeneration, the outcome of two nitric oxide (NO) donor drugs, MyoNovin (M) and isosorbide dinitrate (I), on the effectiveness of the anti-inflammatory drug prednisone (P) in alleviating progression of dystrophy was tested. Dystrophic mdx mice were treated (18 days) as controls or with an NO donor ± P. Fiber permeability and DNA synthesis were labeled by Evans blue dye (EBD) and bromodeoxyuridine uptake, respectively. P decreased body weight gain, M increased quadriceps mass, and I increased heart mass. P increased fiber permeability (%EBD+ fibers) and calcification in diaphragm. Treatment with NO donors + P (M+P, I+P) reduced %EBD+ fibers and calcification vs. P alone. %EBD+ fibers in M+P diaphragm did not differ from control. NO donor treatment reduced proliferation and the population of c-met+ cells and accelerated fiber regeneration. Concurrent with P, NO donor treatment suppressed two important detrimental effects of P in mice, possibly by accelerating regeneration, rebalancing satellite cell quiescence and activation in dystrophy, and/or increasing perfusion. Results suggest that NO donors could improve current therapy for DMD.
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Affiliation(s)
- Wataru Mizunoya
- Dept. of Biological Sciences, Faculty of Science, University of Manitoba, Winnipeg, MB, Canada
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Maes K, Agten A, Smuder A, Powers SK, Decramer M, Gayan-Ramirez G. Corticosteroid effects on ventilator-induced diaphragm dysfunction in anesthetized rats depend on the dose administered. Respir Res 2010; 11:178. [PMID: 21156051 PMCID: PMC3009634 DOI: 10.1186/1465-9921-11-178] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 12/14/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND High dose of corticosteroids has been previously shown to protect against controlled mechanical ventilation (CMV)-induced diaphragmatic dysfunction while inhibiting calpain activation. Because literature suggests that the calpain inhibiting effect of corticosteroid depends on the dose administered, we determined whether lower doses of corticosteroids would also provide protection of the diaphragm during CMV. This may be important for patients undergoing mechanical ventilation and receiving corticosteroids. METHODS Rats were assigned to controls or to 24 hours of CMV while being treated at the start of mechanical ventilation with a single intramuscular administration of either saline, or 5 mg/kg (low MP) or 30 mg/kg (high MP) of methylprednisolone. RESULTS Diaphragmatic force was decreased after CMV and this was exacerbated in the low MP group while high MP rescued this diaphragmatic dysfunction. Atrophy was more severe in the low MP group than after CMV while no atrophy was observed in the high MP group. A significant and similar increase in calpain activity was observed in both the low MP and CMV groups whereas the high dose prevented calpain activation. Expression of calpastatin, the endogenous inhibitor of calpain, was decreased in the CMV and low MP groups but its level was preserved to controls in the high MP group. Caspase-3 activity increased in all CMV groups but to a lesser extent in the low and high MP groups. The 20S proteasome activity was increased in CMV only. CONCLUSIONS Administration of 30 mg/kg methylprednisolone during CMV protected against CMV-induced diaphragm dysfunction while 5 mg/kg was more deleterious. The protective effect is due mainly to an inhibition of the calpain system through preservation of calpastatin levels and to a lesser extent to a caspase-3 inhibition.
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Affiliation(s)
- Karen Maes
- Respiratory Muscle Research Unit, Laboratory of Pneumology and Respiratory Division, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium
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Magne H, Savary-Auzeloux I, Vazeille E, Claustre A, Attaix D, Anne L, Véronique SL, Philippe G, Dardevet D, Combaret L. Lack of muscle recovery after immobilization in old rats does not result from a defect in normalization of the ubiquitin-proteasome and the caspase-dependent apoptotic pathways. J Physiol 2010; 589:511-24. [PMID: 21115641 DOI: 10.1113/jphysiol.2010.201707] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Immobilization periods increase with age because of decreased mobility and/or because of increased pathological episodes that require bed-rest. Then, sarcopaenia might be partially explained by an impaired recovery of skeletal muscle mass after a catabolic state due to an imbalance of muscle protein metabolism, apoptosis and cellular regeneration. Mechanisms involved during muscle recovery have been little studied and in elderly they remain almost unknown. We show, in rats, that a short immobilization period during ageing initiated muscle atrophy that was indeed not recovered after 40 days. Immobilization was associated with an activation of both the ubiquitin-proteasome and the mitochondria-associated apoptotic pathways and the inflammatory and redox processes, and a decrease of cellular regeneration. We show that the lack of muscle recovery during ageing is not due to a defect in proteolysis or apoptosis down-regulation. These observations lead us to hypothesize that muscle protein synthesis activation after immobilization was altered during ageing.
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Affiliation(s)
- Hugues Magne
- INRA, UMR 1019 Unité de Nutrition Humaine, 63122 Saint Genès Champanelle, France.
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Altun M, Besche HC, Overkleeft HS, Piccirillo R, Edelmann MJ, Kessler BM, Goldberg AL, Ulfhake B. Muscle wasting in aged, sarcopenic rats is associated with enhanced activity of the ubiquitin proteasome pathway. J Biol Chem 2010; 285:39597-608. [PMID: 20940294 DOI: 10.1074/jbc.m110.129718] [Citation(s) in RCA: 162] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Among the hallmarks of aged organisms are an accumulation of misfolded proteins and a reduction in skeletal muscle mass ("sarcopenia"). We have examined the effects of aging and dietary restriction (which retards many age-related changes) on components of the ubiquitin proteasome system (UPS) in muscle. The hindlimb muscles of aged (30 months old) rats showed a marked loss of muscle mass and contained 2-3-fold higher levels of 26S proteasomes than those of adult (4 months old) controls. 26S proteasomes purified from muscles of aged and adult rats showed a similar capacity to degrade peptides, proteins, and an ubiquitylated substrate, but differed in levels of proteasome-associated proteins (e.g. the ubiquitin ligase E6AP and deubiquitylating enzyme USP14). Also, the activities of many other deubiquitylating enzymes were greatly enhanced in the aged muscles. Nevertheless, their content of polyubiquitylated proteins was higher than in adult animals. The aged muscles contained higher levels of the ubiquitin ligase CHIP, involved in eliminating misfolded proteins, and MuRF1, which ubiquitylates myofibrillar proteins. These muscles differed from ones rapidly atrophying due to disease, fasting, or disuse in that Atrogin-1/MAFbx expression was low and not inducible by glucocorticoids. Thus, the muscles of aged rats showed many adaptations indicating enhanced proteolysis by the UPS, which may enhance their capacity to eliminate misfolded proteins and seems to contribute to the sarcopenia. Accordingly, dietary restriction decreased or prevented the aging-associated increases in proteasomes and other UPS components and reduced muscle wasting.
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Affiliation(s)
- Mikael Altun
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden.
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Sugiyama A, Hata S, Suzuki K, Yoshida E, Nakano R, Mitra S, Arashida R, Asayama Y, Yabuta Y, Takeuchi T. Oral administration of paramylon, a beta-1,3-D-glucan isolated from Euglena gracilis Z inhibits development of atopic dermatitis-like skin lesions in NC/Nga mice. J Vet Med Sci 2010; 72:755-63. [PMID: 20160419 DOI: 10.1292/jvms.09-0526] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Paramylon is a beta-1,3-D-glucan isolated from Euglena gracilis Z. This study was designed to evaluate the suppressive effects of the oral administration of paramylon on the development of atopic dermatitis (AD)-like skin lesions induced by repeated application of 2,4,6-trinitrochlorobenzene (TNCB) in sensitized NC/Nga mice. The effects of paramylon were assessed by measuring macroscopical and histopathological findings of skin, ear swelling, serum levels of total IgE, interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) and IL-18 and IL-12 contents in the skin lesions. Oral administration of paramylon inhibited the development of AD-like skin lesions as exemplified by a significant decrease in dermatitis scores for the back, ear swelling and hypertrophy of the skin, infiltration of inflammatory cells in the skin, and serum IgE levels. Oral administration of paramylon reduced serum levels of both IL-4 and IFN-gamma and IL-18 and IL-12 contents in the skin lesions. Oral administration of paramylon did not cause weight loss, as was observed with prednisolone. These results suggest that paramylon inhibits the development of AD-like skin lesions in NC/Nga mice by suppressing both the T-helper (Th) 1 and Th 2 cell responses. Our results indicate that paramylon treatment could provide an effective alternative therapy for the management of AD.
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Affiliation(s)
- Akihiko Sugiyama
- Course of Veterinary Laboratory Medicine, School of Veterinary Medicine, Faculty of Agriculture, Tottori University, Japan.
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Aluru N, Vijayan MM. Stress transcriptomics in fish: a role for genomic cortisol signaling. Gen Comp Endocrinol 2009; 164:142-50. [PMID: 19341738 DOI: 10.1016/j.ygcen.2009.03.020] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 03/09/2009] [Accepted: 03/23/2009] [Indexed: 01/17/2023]
Abstract
The physiological responses to stressors, including hormonal profiles and associated tissue responsiveness have been extensively studied in teleosts, but the molecular mechanisms associated with this adaptive response are not well understood. The advent of cDNA microarray technology has transformed the field of functional genomics by revealing global gene expression changes in response to stressor exposures even in non-mammalian vertebrates, including fish. A unifying response in studies related to stressor exposure is activation of the hypothalamus-pituitary-interrenal (HPI) axis in fish, leading to cortisol release into the circulation. Here we will discuss the implications of some of the gene expression changes observed in response to acute stress in fish, while highlighting a role for cortisol in this adaptive stress response. As liver is a key organ for metabolic adjustments to stressors and also is a major target for cortisol action, the genomic studies pertaining to stress and glucocorticoid regulation have focused mainly on this tissue. The studies have identified several genes that are altered transiently after an acute stressor exposure in fish. A number of these stress-responsive genes were also modulated by glucocorticoid receptor activation, suggesting that elevation in cortisol levels during stressor exposure may be a key signal for target tissue molecular programming, essential for stress adaptation. The identification of regulatory gene networks that are stress activated, and modulated by cortisol, both in hepatic and extra-hepatic tissues, including gonads, brain, immune cells and gills, will provide a mechanistic framework to characterize the multifaceted role of cortisol during stress adaptation.
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You YN, Short KR, Jourdan M, Klaus KA, Walrand S, Nair KS. The effect of high glucocorticoid administration and food restriction on rodent skeletal muscle mitochondrial function and protein metabolism. PLoS One 2009; 4:e5283. [PMID: 19381333 PMCID: PMC2667640 DOI: 10.1371/journal.pone.0005283] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 03/11/2009] [Indexed: 11/19/2022] Open
Abstract
Background Glucocorticoids levels are high in catabolic conditions but it is unclear how much of the catabolic effects are due to negative energy balance versus glucocorticoids and whether there are distinct effects on metabolism and functions of specific muscle proteins. Methodology/Principal Findings We determined whether 14 days of high dose methylprednisolone (MPred, 4 mg/kg/d) Vs food restriction (FR, food intake matched to MPred) in rats had different effects on muscle mitochondrial function and protein fractional synthesis rates (FSR). Lower weight loss (15%) occurred in FR than in MPred (30%) rats, while a 15% increase occurred saline-treated Controls. The per cent muscle loss was significantly greater for MPred than FR. Mitochondrial protein FSR in MPred rats was lower in soleus (51 and 43%, respectively) and plantaris (25 and 55%) than in FR, while similar decline in protein FSR of the mixed, sarcoplasmic, and myosin heavy chain occurred. Mitochondrial enzymatic activity and ATP production were unchanged in soleus while in plantaris cytochrome c oxidase activity was lower in FR than Control, and ATP production rate with pyruvate + malate in MPred plantaris was 28% lower in MPred. Branched-chain amino acid catabolic enzyme activities were higher in both FR and MPred rats indicating enhanced amino acid oxidation capacity. Conclusion/Significance MPred and FR had little impact on mitochondrial function but reduction in muscle protein synthesis occurred in MPred that could be explained on the basis of reduced food intake. A greater decline in proteolysis may explain lesser muscle loss in FR than in MPred rats.
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Affiliation(s)
- Y. Nancy You
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Kevin R. Short
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Marion Jourdan
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Katherine A. Klaus
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - Stephane Walrand
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
| | - K. Sreekumaran Nair
- Endocrine Research Unit, Mayo Clinic College of Medicine, Rochester, Minnesota, United States of America
- * E-mail:
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Combaret L, Dardevet D, Béchet D, Taillandier D, Mosoni L, Attaix D. Skeletal muscle proteolysis in aging. Curr Opin Clin Nutr Metab Care 2009; 12:37-41. [PMID: 19057185 DOI: 10.1097/mco.0b013e32831b9c31] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW To understand age-related changes in proteolysis and apoptosis in skeletal muscle in relation to oxidative stress and mitochondrial alterations. RECENT FINDINGS During aging, a progressive loss of muscle mass (sarcopenia) has been described in both human and rodents. Sarcopenia is attributable to an imbalance between protein synthesis and degradation or between apoptosis and regeneration processes or both. Major age-dependent alterations in muscle proteolysis are a lack of responsiveness of the ubiquitin-proteasome-dependent proteolytic pathway to anabolic and catabolic stimuli and alterations in the regulation of autophagy. In addition, increased oxidative stress leads to the accumulation of damaged proteins, which are not properly eliminated, aggregate, and in turn impair proteolytic activities. Finally, the mitochondria-associated apoptotic pathway may be activated. These age-induced changes may contribute to sarcopenia and decreased ability of old individuals to recover from stress. SUMMARY Alterations in proteasome-dependent or lysosomal proteolysis, increased oxidative stress, mitochondrial dysfunction, and apoptosis presumably contribute to the development of sarcopenia.
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Affiliation(s)
- Lydie Combaret
- INRA, Centre Clermont-Ferrand-Theix, UMR1019, Unité Nutrition Humaine, St. Genès Champanelle, France.
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Abstract
The activity of the pituitary-adrenal axis can profoundly impact on body composition. This is dramatically seen in Cushing's syndrome (CS) but changes in body composition are also implicated in depression and alcoholic pseudocushing's. The pathophysiological mechanisms underlying these changes remain poorly understood. Changes to body composition in CS include increased fat mass, decreased bone mass, thinning of the skin and reduced lean mass. Why these tissues are affected so dramatically is unclear. Additionally, the change in body composition between individuals varies considerably for reasons which are only now becoming evident. This paper reviews the phenotypic changes with altered pituitary-adrenal axis activity and discusses the mechanisms involved. The primary focus is on adipose, bone, muscle and skin since the most dramatic changes are seen in these tissues.
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Affiliation(s)
- Eva Fernandez-Rodriguez
- Division of Medical Sciences, The Institute of Biomedical Research, The Medical School, The University of Birmingham, Birmingham , B15 2TH, UK
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Rajan V, Mitch WE. Ubiquitin, proteasomes and proteolytic mechanisms activated by kidney disease. Biochim Biophys Acta Mol Basis Dis 2008; 1782:795-9. [PMID: 18723090 DOI: 10.1016/j.bbadis.2008.07.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 07/27/2008] [Accepted: 07/30/2008] [Indexed: 01/08/2023]
Abstract
The ubiquitin-proteasome system (UPS) includes 3 enzymes that conjugate ubiquitin to intracellular proteins that are then recognized and degraded in the proteasome. The process participates in the regulation of cell metabolism. In the kidney, the UPS regulates the turnover of transporters and signaling proteins and its activity is down regulated in acidosis-induced proximal tubular cell hypertrophy. In chronic kidney disease (CKD), muscle wasting occurs because complications of CKD including acidosis, insulin resistance, inflammation, and increased angiotensin II levels stimulate the UPS to degrade muscle proteins. This response also includes caspase-3 and calpains which act to cleave muscle proteins to provide substrates for the UPS. For example, caspase-3 degrades actomyosin, leaving a 14 kDa fragment of actin in muscle. The 14 kDa actin fragment is increased in muscle of patient with kidney disease, burn injury and surgery. In addition, acidosis, insulin resistance, inflammation and angiotensin II stimulate glucocorticoid production. Glucocorticoids are also required for the muscle wasting that occurs in CKD. Thus, the UPS is involved in regulating kidney function and participates in highly organized responses that degrade muscle protein in response to loss of kidney function.
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Affiliation(s)
- Vik Rajan
- Nephrology Division, M/S: BCM 285 Baylor College of Medicine, One Baylor Plaza, Alkek N-520 Houston, TX 77030, USA
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Betters JL, Long JH, Howe KS, Braith RW, Soltow QA, Lira VA, Criswell DS. Nitric oxide reverses prednisolone-induced inactivation of muscle satellite cells. Muscle Nerve 2007; 37:203-9. [DOI: 10.1002/mus.20915] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Menconi M, Fareed M, O'Neal P, Poylin V, Wei W, Hasselgren PO. Role of glucocorticoids in the molecular regulation of muscle wasting. Crit Care Med 2007; 35:S602-8. [PMID: 17713416 DOI: 10.1097/01.ccm.0000279194.11328.77] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To review glucocorticoid-regulated molecular mechanisms of muscle wasting. DESIGN Review of recent literature describing the role of glucocorticoids in the regulation of proteolytic mechanisms, transcription factors, and nuclear cofactors in skeletal muscle during various catabolic conditions. MAIN RESULTS Catabolic doses of glucocorticoids induce muscle atrophy both in vivo and in vitro by stimulating protein breakdown and inhibiting protein synthesis. Signaling pathways that regulate muscle protein synthesis at the translational level are inhibited by glucocorticoids. Glucocorticoids increase the expression and activity of the ubiquitin-proteasome pathway, a major proteolytic mechanism of muscle atrophy. The expression and activity of muscle wasting-related transcription factors, including C/EBPbeta and delta and Forkhead box O 1, 3, and 4, as well as the nuclear cofactor p300, are up-regulated by glucocorticoid excess. CONCLUSIONS Muscle wasting in various catabolic conditions is, at least in part, regulated by glucocorticoids. The role of glucocorticoids in muscle wasting is complex and reflects regulation at the molecular level of multiple mechanisms influencing both synthesis and degradation of muscle proteins.
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Affiliation(s)
- Michael Menconi
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Aluru N, Vijayan MM. Hepatic transcriptome response to glucocorticoid receptor activation in rainbow trout. Physiol Genomics 2007; 31:483-91. [PMID: 17848605 DOI: 10.1152/physiolgenomics.00118.2007] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cortisol, the principal corticosteroid in teleosts, is thought to play a key role in the metabolic adjustments critical for regaining homeostasis. However, the target tissue molecular mechanisms involved in this adaptive response to corticosteroid stimulation are still unclear. Cortisol signaling is mediated predominantly by the glucocorticoid receptor (GR), and previous studies have shown that RU486 (a GR antagonist) offsets corticosteroid signaling in teleosts. To elucidate the molecular basis of GR-mediated metabolic readjustments, we exposed primary culture of trout hepatocytes in vitro to cortisol (to mimic stressed levels seen in fish), RU486, or a combination of both for 24 h. The gene expression was analyzed using a low-density custom-made rainbow trout cDNA array enriched with endocrine-, metabolic-, and stress-related genes. The microarray results for select genes were further validated using quantitative real-time PCR. Cortisol treatment significantly increased glucose production in hepatocytes, and this response was blocked by RU486, confirming GR-mediated corticosteroid signaling. Cortisol also elevated GR transcript levels, and this response was abolished by RU486, whereas both cortisol and RU486, either alone or in combination, reduced GR protein content in trout hepatocytes. Cortisol treatment significantly modulated the expression of several genes known to be involved in intermediary metabolism, cellular stress response, reproduction, and xenobiotic metabolism. Most of these cortisol-mediated transcript changes were abolished in the presence of RU486, suggesting a key role for GR-specific signaling in this adaptive response. Taken together, our results suggest a key role for genomic cortisol signaling in the liver molecular reprogramming that is critical for coping with stress in fish.
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Dargelos E, Brulé C, Combaret L, Hadj-Sassi A, Dulong S, Poussard S, Cottin P. Involvement of the calcium-dependent proteolytic system in skeletal muscle aging. Exp Gerontol 2007; 42:1088-98. [PMID: 17937979 DOI: 10.1016/j.exger.2007.08.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Revised: 08/28/2007] [Accepted: 08/30/2007] [Indexed: 12/25/2022]
Abstract
Aging is associated with a progressive and involuntary loss of muscle mass also known as sarcopenia. This condition represents a major public health concern with high socio-economics implications. Although sarcopenia is well documented, the aetiology of this condition still remains poorly understood. Calpains are ubiquitous proteases regulated in part by a specific inhibitor, calpastatin. They are well known to have major implications in muscle growth and differentiation. The aim of the present study was to determine if this proteolytic system could be involved in the phenotype associated with sarcopenia. Calpains and calpastatin levels, subcellular distributions and activities were compared between muscles from 3 and 24 months old rats. Altogether, the results we obtained showed an overall increase in calpain activities associated with muscle aging. These findings suggest that the calcium-dependent proteolytic system is indeed involved in sarcopenia.
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Affiliation(s)
- Elise Dargelos
- Université Bordeaux I, INRA USC 2009, Unité Protéolyse Croissance et Développement Musculaire, ISTAB, avenue des facultés, 33405 Talence Cedex, France.
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