701
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Prak RF, Doestzada M, Thomas CK, Tepper M, Zijdewind I. Reduced voluntary drive during sustained but not during brief maximal voluntary contractions in the first dorsal interosseous weakened by spinal cord injury. J Appl Physiol (1985) 2015; 119:1320-9. [PMID: 26404618 DOI: 10.1152/japplphysiol.00399.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 09/22/2015] [Indexed: 11/22/2022] Open
Abstract
In able-bodied (AB) individuals, voluntary muscle activation progressively declines during sustained contractions. However, few data are available on voluntary muscle activation during sustained contractions in muscles weakened by spinal cord injury (SCI), where greater force declines may limit task performance. SCI-related impairment of muscle activation complicates interpretation of the interpolated twitch technique commonly used to assess muscle activation. We attempted to estimate and correct for the SCI-related-superimposed twitch. Seventeen participants, both AB and with SCI (American Spinal Injury Association Impairment Scale C/D) produced brief and sustained (2-min) maximal voluntary contractions (MVCs) with the first dorsal interosseous. Force and electromyography were recorded together with superimposed (doublet) twitches. MVCs of participants with SCI were weaker than those of AB participants (20.3 N, SD 7.1 vs. 37.9 N, SD 9.5; P < 0.001); MVC-superimposed twitches were larger in participants with SCI (SCI median 10.1%, range 2.0-63.2%; AB median 4.7%, range 0.0-18.4% rest twitch; P = 0.007). No difference was found after correction for the SCI-related-superimposed twitch (median 6.7%, 0.0-17.5% rest twitch, P = 0.402). Thus during brief contractions, the maximal corticofugal output that participants with SCI could exert was similar to that of AB participants. During the sustained contraction, force decline (SCI, 58.0%, SD 15.1; AB, 57.2% SD 13.3) was similar (P = 0.887) because participants with SCI developed less peripheral (P = 0.048) but more central fatigue than AB participants. The largest change occurred at the start of the sustained contraction when the (corrected) superimposed twitches increased more in participants with SCI (SCI, 16.3% rest twitch, SD 20.8; AB, 2.7%, SD 4.7; P = 0.01). The greater reduction in muscle activation after SCI may relate to a reduced capacity to overcome fast fatigue-related excitability changes at the spinal level.
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Affiliation(s)
- Roeland F Prak
- Department of Neuroscience, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Marwah Doestzada
- Department of Neuroscience, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Christine K Thomas
- The Miami Project to Cure Paralysis, Departments of Neurological Surgery, Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, Florida; and
| | - Marga Tepper
- Department of Rehabilitation Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Inge Zijdewind
- Department of Neuroscience, University Medical Center Groningen, University of Groningen, The Netherlands;
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702
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Zhang YY, Huang J, Yang M, Gu LJ, Ji JY, Wang LJ, Yuan WJ. Effect of a low-protein diet supplemented with keto-acids on autophagy and inflammation in 5/6 nephrectomized rats. Biosci Rep 2015; 35:e00263. [PMID: 26371333 DOI: 10.1042/BSR20150069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 09/08/2015] [Indexed: 12/31/2022] Open
Abstract
The present study demonstrated that autophagy/mitophagy was increased and inflammation was aggravated in skeletal muscle in chronic kidney disease (CKD) rats. A low-protein diet (LPD) supplemented with ketoacids (KA) improved the loss in muscle mass and blocked the activation of autophagy/mitophagy and inflammation in those rats. Ketoacids (KA) are known to preserve muscle mass among patients with chronic kidney disease (CKD) on a low-protein diet (LPD). The present study was to compare the effects of KA supplemented diet therapy in autophagy and inflammation in CKD rats' skeletal muscle. Rats with 5/6 nephrectomy were randomly divided into three groups and fed with either 11 g/kg/day protein [normal-protein diet (NPD)], 3 g/kg/day protein (LPD) or 3 g/kg/day protein which including 5% protein plus 1% KA (LPD + KA) for 24 weeks. Sham-operated rats with NPD intake were used as control. LPD could improve body weight, gastrocnemius muscle mass, as well as gastrocnemius muscle cross-sectional area, with the effect being more obvious in the LPD + KA group. The autophagy marker LC3 (microtubule-associated protein 1 light chain 3), p62, Parkin and PTEN induced putative kinase 1 (PINK1) were significantly attenuate in LPD + KA group than LPD group. LPD + KA group had the lower total mtDNA (mitochondiral DNA) and cytosol mtDNA, NACHT-PYD-containing protein 3 (NALP3) inflammasome than LPD group, but its reactive oxygen species (ROS), caspase-1 and apoptosis-associated speck-like protein containing a CARD (ASC) level was higher. Immunoblotting showed IL-1β (interleukin-1-beta) was lower in LPD and LPD + KA group than the NPD group, but IL-18 showed no significant difference among control and CKD group; toll-like receptor signalling-dependent IL-6 was higher in LPD + KA group than LPD group, but tumor necrosis factor-α (TNF-α) was not significantly changed between LPD + KA and LPD group. Systematic changes of the four cytokines were different from that of the tissue. Although LPD + KA could further ameliorate-activated autophagy than LPD, its effect on the activated inflammation state in CKD was not distinctly. Further study is still required to explore the method of ameliorating inflammation to provide new therapeutic approaches for CKD protein energy wasting (PEW).
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703
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Strube P, Putzier M, Streitparth F, Hoff EK, Hartwig T. Postoperative posterior lumbar muscle changes and their relationship to segmental motion preservation or restriction: a randomized prospective study. J Neurosurg Spine 2015; 24:25-31. [PMID: 26360146 DOI: 10.3171/2015.3.spine14997] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To date, it remains unclear whether the preservation of segmental motion by total disc replacement (TDR) or motion restriction by stand-alone anterior lumbar interbody fusion (ALIF) have an influence on postoperative degeneration of the posterior paraspinal muscles or the associated clinical results. Therefore, the purpose of the present prospective randomized study was to evaluate the clinical parameters and 3D quantitative radiological changes in the paraspinal muscles of the lumbar spine in surgically treated segments and superior adjacent segments after ALIF and TDR. METHODS A total of 50 patients with chronic low-back pain caused by single-level intervertebral disc degeneration (Pfirrmann Grade ≥ III) and/or osteochondrosis (Modic Type ≤ 2) without symptomatic facet joint degeneration (Fujiwara Grade ≤ 2, infiltration test) of the segments L4-5 or L5-S1 were randomly assigned to 2 treatment groups. Twenty-five patients were treated with a stand-alone ALIF and the remaining 25 patients underwent TDR. For ALIF and TDR, a retroperitoneal approach was used. At 1 week and at 12 months after surgery, CT was used to analyze paraspinal lumbar muscle tissue volume and relative fat content. Residual muscle tissue volume at 12 months and change in the relative fat content were compared between the groups. In addition, clinical parameters (visual analog scale [VAS] for low-back pain and Oswestry Disability Index [ODI] Questionnaire Version 2 for function) were compared. RESULTS Compared with 1 week after surgery, the radiological analysis at 12 months revealed a small decrease in the posterior muscle volume (the mean decrease was < 2.5%), along with a small increase in the relative fat content (the mean increase was < 1.9%), in both groups at the index and superior adjacent segments. At the adjacent segment, the ALIF group presented significantly less muscle tissue volume atrophy and a smaller increase in fat content compared with the TDR group. At final follow-up, the clinical parameters related to pain and function were significantly improved in both groups compared with 1 week postsurgery, but there were no differences between the groups. CONCLUSIONS Motion restriction via stand-alone ALIF and motion preservation via TDR both present small changes in the posterior lumbar paraspinal muscles with regard to volume atrophy or fatty degeneration at the index and superior adjacent segments. Therefore, although the clinical outcome was not affected by the observed muscular changes, the authors concluded that the expected negative influence of motion restriction on the posterior muscles compared with motion preservation does not occur on a clinically relevant level.
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Affiliation(s)
- Patrick Strube
- Klinik für Orthopädie der Friedrich-Schiller-Universität Jena, Waldkrankenhaus "Rudolf Elle" gGmbH, Eisenberg
| | - Michael Putzier
- Klinik für Orthopädie, Centrum für Muskuloskeletale Chirurgie, Charité - Universitätsmedizin Berlin; and
| | | | - Eike K Hoff
- Klinik für Orthopädie, Centrum für Muskuloskeletale Chirurgie, Charité - Universitätsmedizin Berlin; and
| | - Tony Hartwig
- Klinik für Orthopädie, Centrum für Muskuloskeletale Chirurgie, Charité - Universitätsmedizin Berlin; and
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704
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Kwon OS, Smuder AJ, Wiggs MP, Hall SE, Sollanek KJ, Morton AB, Talbert EE, Toklu HZ, Tumer N, Powers SK. AT1 receptor blocker losartan protects against mechanical ventilation-induced diaphragmatic dysfunction. J Appl Physiol (1985) 2015; 119:1033-41. [PMID: 26359481 DOI: 10.1152/japplphysiol.00237.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 09/04/2015] [Indexed: 11/22/2022] Open
Abstract
Mechanical ventilation is a life-saving intervention for patients in respiratory failure. Unfortunately, prolonged ventilator support results in diaphragmatic atrophy and contractile dysfunction leading to diaphragm weakness, which is predicted to contribute to problems in weaning patients from the ventilator. While it is established that ventilator-induced oxidative stress is required for the development of ventilator-induced diaphragm weakness, the signaling pathway(s) that trigger oxidant production remain unknown. However, recent evidence reveals that increased plasma levels of angiotensin II (ANG II) result in oxidative stress and atrophy in limb skeletal muscles. Using a well-established animal model of mechanical ventilation, we tested the hypothesis that increased circulating levels of ANG II are required for both ventilator-induced diaphragmatic oxidative stress and diaphragm weakness. Cause and effect was determined by administering an angiotensin-converting enzyme inhibitor (enalapril) to prevent ventilator-induced increases in plasma ANG II levels, and the ANG II type 1 receptor antagonist (losartan) was provided to prevent the activation of ANG II type 1 receptors. Enalapril prevented the increase in plasma ANG II levels but did not protect against ventilator-induced diaphragmatic oxidative stress or diaphragm weakness. In contrast, losartan attenuated both ventilator-induced oxidative stress and diaphragm weakness. These findings indicate that circulating ANG II is not essential for the development of ventilator-induced diaphragm weakness but that activation of ANG II type 1 receptors appears to be a requirement for ventilator-induced diaphragm weakness. Importantly, these experiments provide the first evidence that the Food and Drug Administration-approved drug losartan may have clinical benefits to protect against ventilator-induced diaphragm weakness in humans.
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Affiliation(s)
- Oh Sung Kwon
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Ashley J Smuder
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Michael P Wiggs
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Stephanie E Hall
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Kurt J Sollanek
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Aaron B Morton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Erin E Talbert
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida
| | - Hale Z Toklu
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, Florida; and Geriatric Research, Education, and Clinical Center, North Florida/South Georgia Veterans Health System, Gainesville, Florida
| | - Nihal Tumer
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, Florida; and Geriatric Research, Education, and Clinical Center, North Florida/South Georgia Veterans Health System, Gainesville, Florida
| | - Scott K Powers
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida;
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705
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Wang F, Zhang P, Liu H, Fan M, Chen X. Proteomic analysis of mouse soleus muscles affected by hindlimb unloading and reloading. Muscle Nerve 2015; 52:803-11. [PMID: 25656502 DOI: 10.1002/mus.24590] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 01/21/2015] [Accepted: 01/25/2015] [Indexed: 11/11/2022]
Abstract
INTRODUCTION Disuse muscle atrophy, induced by prolonged space flight, bed rest, or denervation, is a common process with obvious changes in slow-twitch soleus muscles. METHODS Proteomic analysis was performed on mouse soleus subjected to hindlimb unloading (HU) and hindlimb reloading (HR) to identify new dysregulated proteins. RESULTS Following HU, the mass and cross-sectional area of muscle fibers decreased, but they recovered after HR. Proteomic analyses revealed 9 down-regulated and 7 up-regulated proteins in HU, and 2 down-regulated and 5 up-regulated proteins in HR. The dysregulated proteins were mainly involved in energy metabolism, protein degradation, and cytoskeleton stability. Among the dysregulated proteins were fatty acid binding protein 3, α-B crystalline, and transthyretin. CONCLUSIONS These results indicate that muscle atrophy induced by unloading is related to activation of proteolysis, metabolic alterations toward glycolysis, destruction of myofibrillar integrity, and dysregulation of heat shock proteins (HSPs). The dysregulated proteins may play a role in muscle atrophy and the recovery process.
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Affiliation(s)
- Fei Wang
- National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, No. 26 Beiqing Road, Beijing, 100094, P.R. Beijing, China
| | - Peng Zhang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Hongju Liu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Ming Fan
- Department of Cognitive Science, Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Xiaoping Chen
- National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, No. 26 Beiqing Road, Beijing, 100094, P.R. Beijing, China.,State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
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706
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Barber L, Scicchitano BM, Musaro A. Molecular and Cellular Mechanisms of Muscle Aging and Sarcopenia and Effects of Electrical Stimulation in Seniors. Eur J Transl Myol 2015; 25:231-6. [PMID: 26913161 PMCID: PMC4748976 DOI: 10.4081/ejtm.2015.5227] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The prolongation of skeletal muscle strength in aging and neuromuscular disease has been the objective of numerous studies employing a variety of approaches. It is generally accepted that cumulative failure to repair damage related to an overall decrease in anabolic processes is a primary cause of functional impairment in muscle. The functional performance of skeletal muscle tissues declines during post- natal life and it is compromised in different diseases, due to an alteration in muscle fiber composition and an overall decrease in muscle integrity as fibrotic invasions replace functional contractile tissue. Characteristics of skeletal muscle aging and diseases include a conspicuous reduction in myofiber plasticity (due to the progressive loss of muscle mass and in particular of the most powerful fast fibers), alteration in muscle-specific transcriptional mechanisms, and muscle atrophy. An early decrease in protein synthetic rates is followed by a later increase in protein degradation, to affect biochemical, physiological, and morphological parameters of muscle fibers during the aging process. Alterations in regenerative pathways also compromise the functionality of muscle tissues. In this review we will give an overview of the work on molecular and cellular mechanisms of aging and sarcopenia and the effects of electrical stimulation in seniors..
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Affiliation(s)
- Laura Barber
- Institute Pasteur Cenci-Bolognetti, DAHFMO-unit of Histology and Medical Embryology, IIM, Sapienza University of Rome , Italy
| | | | - Antonio Musaro
- Institute Pasteur Cenci-Bolognetti, DAHFMO-unit of Histology and Medical Embryology, IIM, Sapienza University of Rome, Italy; Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, ItalyI
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707
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Lee YH, Kim WJ, Lee MH, Kim SY, Seo DH, Kim HS, Gelinsky M, Kim TJ. Anti-skeletal muscle atrophy effect of Oenothera odorata root extract via reactive oxygen species-dependent signaling pathways in cellular and mouse model. Biosci Biotechnol Biochem 2015; 80:80-8. [PMID: 26613402 DOI: 10.1080/09168451.2015.1075861] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Skeletal muscle atrophy can be defined as a decrease of muscle volume caused by injury or lack of use. This condition is associated with reactive oxygen species (ROS), resulting in various muscular disorders. We acquired 2D and 3D images using micro-computed tomography in gastrocnemius and soleus muscles of sciatic-denervated mice. We confirmed that sciatic denervation-small animal model reduced muscle volume. However, the intraperitoneal injection of Oenothera odorata root extract (EVP) delayed muscle atrophy compared to a control group. We also investigated the mechanism of muscle atrophy's relationship with ROS. EVP suppressed expression of SOD1, and increased expression of HSP70, in both H2O2-treated C2C12 myoblasts and sciatic-denervated mice. Moreover, EVP regulated apoptotic signals, including caspase-3, Bax, Bcl-2, and ceramide. These results indicate that EVP has a positive effect on reducing the effect of ROS on muscle atrophy.
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Affiliation(s)
- Yong-Hyeon Lee
- a Division of Biological Science and Technology, Yonsei-Fraunhofer Medical Device Lab , College of Science and Technology, Yonsei University , Wonju , Korea
| | - Wan-Joong Kim
- a Division of Biological Science and Technology, Yonsei-Fraunhofer Medical Device Lab , College of Science and Technology, Yonsei University , Wonju , Korea
| | - Myung-Hun Lee
- a Division of Biological Science and Technology, Yonsei-Fraunhofer Medical Device Lab , College of Science and Technology, Yonsei University , Wonju , Korea
| | - Sun-Young Kim
- a Division of Biological Science and Technology, Yonsei-Fraunhofer Medical Device Lab , College of Science and Technology, Yonsei University , Wonju , Korea
| | - Dong-Hyun Seo
- b Department of Biomedical Engineering, Yonsei-Fraunhofer Medical Device Lab , College of Health Science, Yonsei University , Wonju , Korea
| | - Han-Sung Kim
- b Department of Biomedical Engineering, Yonsei-Fraunhofer Medical Device Lab , College of Health Science, Yonsei University , Wonju , Korea
| | - Michael Gelinsky
- c Center for Translational Bone, Joint and Soft Tissue Research, Medical Faculty and University Hospital, Technische Universität Dresden , Dresden , Germany
| | - Tack-Joong Kim
- a Division of Biological Science and Technology, Yonsei-Fraunhofer Medical Device Lab , College of Science and Technology, Yonsei University , Wonju , Korea
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708
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Roberts PA, Bouitbir J, Bonifacio A, Singh F, Kaufmann P, Urwyler A, Krähenbühl S. Contractile function and energy metabolism of skeletal muscle in rats with secondary carnitine deficiency. Am J Physiol Endocrinol Metab 2015; 309:E265-74. [PMID: 26037247 DOI: 10.1152/ajpendo.00001.2015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 05/26/2015] [Indexed: 11/22/2022]
Abstract
The consequences of carnitine depletion upon metabolic and contractile characteristics of skeletal muscle remain largely unexplored. Therefore, we investigated the effect of N-trimethyl-hydrazine-3-propionate (THP) administration, a carnitine analog inhibiting carnitine biosynthesis and renal reabsorption of carnitine, on skeletal muscle function and energy metabolism. Male Sprague-Dawley rats were fed a standard rat chow in the absence (CON; n = 8) or presence of THP (n = 8) for 3 wk. Following treatment, rats were fasted for 24 h prior to excision of their soleus and EDL muscles for biochemical characterization at rest and following 5 min of contraction in vitro. THP treatment reduced the carnitine pool by ∼80% in both soleus and EDL muscles compared with CON. Carnitine depletion was associated with a 30% decrease soleus muscle weight, whereas contractile function (expressed per gram of muscle), free coenzyme A, and water content remained unaltered from CON. Muscle fiber distribution and fiber area remained unaffected, whereas markers of apoptosis were increased in soleus muscle of THP-treated rats. In EDL muscle, carnitine depletion was associated with reduced free coenzyme A availability (-25%, P < 0.05), impaired peak tension development (-44%, P < 0.05), and increased glycogen hydrolysis (52%, P < 0.05) during muscle contraction, whereas PDC activation, muscle weight, and water content remained unaltered from CON. In conclusion, myopathy associated with carnitine deficiency can have different causes. Although muscle atrophy, most likely due to increased apoptosis, is predominant in muscle composed predominantly of type I fibers (soleus), disturbance of energy metabolism appears to be the major cause in muscle composed of type II fibers (EDL).
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Affiliation(s)
- Paul A Roberts
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
| | - Jamal Bouitbir
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
| | - Annalisa Bonifacio
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
| | - François Singh
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
| | - Priska Kaufmann
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
| | - Albert Urwyler
- Department of Biomedicine, and Department of Anesthesia, University Hospital Basel, Basel, Switzerland
| | - Stephan Krähenbühl
- Division of Clinical Pharmacology and Toxicology, Department of Biomedicine, and
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709
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Mendias CL, Bakhurin KI, Gumucio JP, Shallal‐Ayzin MV, Davis CS, Faulkner JA. Haploinsufficiency of myostatin protects against aging-related declines in muscle function and enhances the longevity of mice. Aging Cell 2015; 14:704-6. [PMID: 25808276 PMCID: PMC4531085 DOI: 10.1111/acel.12339] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/14/2015] [Indexed: 01/17/2023] Open
Abstract
The molecular mechanisms behind aging-related declines in muscle function are not well understood, but the growth factor myostatin (MSTN) appears to play an important role in this process. Additionally, epidemiological studies have identified a positive correlation between skeletal muscle mass and longevity. Given the role of myostatin in regulating muscle size, and the correlation between muscle mass and longevity, we tested the hypotheses that the deficiency of myostatin would protect oldest-old mice (28-30 months old) from an aging-related loss in muscle size and contractility, and would extend the maximum lifespan of mice. We found that MSTN(+/-) and MSTN(-/-) mice were protected from aging-related declines in muscle mass and contractility. While no differences were detected between MSTN(+/+) and MSTN(-/-) mice, MSTN(+/-) mice had an approximately 15% increase in maximal lifespan. These results suggest that targeting myostatin may protect against aging-related changes in skeletal muscle and contribute to enhanced longevity.
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Affiliation(s)
- Christopher L. Mendias
- Department of Orthopaedic Surgery University of Michigan Medical School Ann Arbor MI USA
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
| | - Konstantin I. Bakhurin
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
| | - Jonathan P. Gumucio
- Department of Orthopaedic Surgery University of Michigan Medical School Ann Arbor MI USA
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
| | - Mark V. Shallal‐Ayzin
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
| | - Carol S. Davis
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
| | - John A. Faulkner
- Department of Molecular & Integrative Physiology University of Michigan Medical School Ann Arbor MI USA
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710
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Jang J, Yun HY, Park J, Lim K. Protective effect of branched chain amino acids on hindlimb suspension-induced muscle atrophy in growing rats. J Exerc Nutrition Biochem 2015; 19:183-9. [PMID: 26527098 PMCID: PMC4624119 DOI: 10.5717/jenb.2015.15062704] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 06/08/2015] [Accepted: 06/27/2015] [Indexed: 11/04/2022] Open
Abstract
PURPOSE The effect of BCAA (branched chain amino acid) administration on muscle atrophy during growth phases is not well known. We investigated whether BCAA administration can prevent the muscle atrophy induced by hindlimb suspension in growing male rats. METHODS Male Wistar rats were assigned to 1 of 2 groups (n = 7/group): hindlimb suspension and hindlimb suspension with oral BCAA administration (600 mg·kg(-1)·day(-1), valine 1: leucine 2: isoleucine 1). After 14 days of hindlimb suspension, the weight and mRNA levels of the soleus muscle were measured. RESULTS BCAA administration prevented a decrease in soleus muscle weight. BCAA administration attenuated atrogin-1 and MuRF1 mRNA expression, which has been reported to play a pivotal role in muscle atrophy. CONCLUSION BCAA could serve as an effective supplement for the prevention or treatment of muscle atrophy, especially atrophy caused by weightlessness.
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Affiliation(s)
- Jiwoong Jang
- Laboratory of Exercise Nutrition, Department of Physical Education, Konkuk University, Seoul, Republic of Korea
| | - Hea-Yeon Yun
- Physical Activity and Performance Institute (PAPI), Konkuk University, Seoul, Republic of Korea
| | - Jonghoon Park
- Laboratory of Exercise Nutrition, Department of Physical Education, Konkuk University, Seoul, Republic of Korea ; Physical Activity and Performance Institute (PAPI), Konkuk University, Seoul, Republic of Korea
| | - Kiwon Lim
- Laboratory of Exercise Nutrition, Department of Physical Education, Konkuk University, Seoul, Republic of Korea ; Physical Activity and Performance Institute (PAPI), Konkuk University, Seoul, Republic of Korea
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711
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Mônico-Neto M, Antunes HKM, Lee KS, Phillips SM, Giampá SQDC, Souza HDS, Dáttilo M, Medeiros A, de Moraes WM, Tufik S, de Mello MT. Resistance training minimizes catabolic effects induced by sleep deprivation in rats. Appl Physiol Nutr Metab 2015; 40:1143-50. [PMID: 26513007 DOI: 10.1139/apnm-2015-0061] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Sleep deprivation (SD) can induce muscle atrophy. We aimed to investigate the changes underpinning SD-induced muscle atrophy and the impact of this condition on rats that were previously submitted to resistance training (RT). Adult male Wistar EPM-1 rats were randomly allocated into 1 of 5 groups: control, sham, SD (for 96 h), RT, and RT+SD. The major outcomes of this study were muscle fiber cross-sectional area (CSA), anabolic and catabolic hormone profiles, and the abundance of select proteins involved in muscle protein synthesis and degradation pathways. SD resulted in muscle atrophy; however, when SD was combined with RT, the reduction in muscle fiber CSA was attenuated. The levels of IGF-1 and testosterone were reduced in SD animals, and the RT+SD group had higher levels of these hormones than the SD group. Corticosterone was increased in the SD group compared with the control group, and this increase was minimized in the RT+SD group. The increases in corticosterone concentrations paralleled changes in the abundance of ubiquitinated proteins and the autophagic proteins LC3 and p62/SQSTM1, suggesting that corticosterone may trigger these changes. SD induced weight loss, but this loss was minimized in the RT+SD group. We conclude that SD induced muscle atrophy, probably because of the increased corticosterone and catabolic signal. High-intensity RT performed before SD was beneficial in containing muscle loss induced by SD. It also minimized the catabolic signal and increased synthetic activity, thereby minimizing the body's weight loss.
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Affiliation(s)
- Marcos Mônico-Neto
- a Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.,b Laboratório Interdisciplinar em Fisiologia e Exercício, São Paulo, Brazil
| | - Hanna Karen Moreira Antunes
- b Laboratório Interdisciplinar em Fisiologia e Exercício, São Paulo, Brazil.,c Department of Biosciences, Universidade Federal de São Paulo, Santos, Brazil
| | - Kil Sun Lee
- d Department of Biochemistry, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Stuart M Phillips
- e Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | - Sara Quaglia de Campos Giampá
- b Laboratório Interdisciplinar em Fisiologia e Exercício, São Paulo, Brazil.,c Department of Biosciences, Universidade Federal de São Paulo, Santos, Brazil
| | - Helton de Sá Souza
- a Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.,b Laboratório Interdisciplinar em Fisiologia e Exercício, São Paulo, Brazil
| | - Murilo Dáttilo
- a Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.,b Laboratório Interdisciplinar em Fisiologia e Exercício, São Paulo, Brazil
| | - Alessandra Medeiros
- c Department of Biosciences, Universidade Federal de São Paulo, Santos, Brazil
| | | | - Sergio Tufik
- a Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Marco Túlio de Mello
- a Department of Psychobiology, Universidade Federal de São Paulo, São Paulo, Brazil.,f School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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712
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Abstract
Cachexia is an exacerbating event in many types of cancer that is strongly associated with a poor prognosis. We have identified cytokine, signaling, and transcription factors that are required for cachexia in the mouse C26 colon carcinoma model of cancer. C2C12 myotubes treated with conditioned medium from C26 cancer cells induced atrophy and activated a STAT-dependent reporter gene but not reporter genes dependent on SMAD, FOXO, C/EBP, NF-κB, or AP-1. Of the gp130 family members IL-11, IL-6, oncostatin M (OSM), and leukemia inhibitory factor (LIF), only OSM and LIF were sufficient to activate the STAT reporter in myotubes. LIF was elevated in C26 conditioned medium (CM), but IL-6, OSM, TNFα, and myostatin were not. A LIF-blocking antibody abolished C26 CM-induced STAT reporter activation, STAT3 phosphorylation, and myotube atrophy but blocking antibodies to IL-6 or OSM did not. JAK2 inhibitors also blocked C26 CM-induced STAT reporter activation, STAT3 phosphorylation, and atrophy in myotubes. LIF at levels found in the C26 CM was sufficient for STAT reporter activation and atrophy in myotubes. In vivo, an increase in serum LIF preceded the increase in IL-6 in mice with C26 tumors. Overexpression of a dominant negative Stat3Cβ-EGFP gene in myotubes and in mouse muscle blocked the atrophy caused by C26 CM or C26 tumors, respectively. Taken together, these data support an important role of LIF-JAK2-STAT3 in C26 cachexia and point to a therapeutic approach for at least some types of cancer cachexia.
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Affiliation(s)
- Danielle N Seto
- From the Department of Health Sciences, Boston University, Boston, Massachusetts 02215
| | - Susan C Kandarian
- From the Department of Health Sciences, Boston University, Boston, Massachusetts 02215
| | - Robert W Jackman
- From the Department of Health Sciences, Boston University, Boston, Massachusetts 02215
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713
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Mendes P, Wickerson L, Helm D, Janaudis-Ferreira T, Brooks D, Singer LG, Mathur S. Skeletal muscle atrophy in advanced interstitial lung disease. Respirology 2015; 20:953-9. [PMID: 26081374 DOI: 10.1111/resp.12571] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/02/2015] [Accepted: 03/27/2015] [Indexed: 01/26/2023]
Abstract
BACKGROUND AND OBJECTIVE A limited number of studies examine skeletal muscle dysfunction in individuals with interstitial lung disease (ILD). We compared upper and lower limb muscle size and strength in individuals with advanced ILD with healthy controls. Second, the relationships of muscle size to muscle strength and function were explored. METHODS Individuals with advanced ILD listed for lung transplant and healthy control subjects were studied. B-mode ultrasound was performed to assess cross-sectional area (CSA) of rectus femoris and thickness of gastrocnemius and soleus and biceps brachii. Subjects performed isometric muscle strength testing, Short Physical Performance Battery, Timed Up and Go, and Unsupported Upper Limb Exercise Test. RESULTS Twenty-six individuals with advanced ILD (61 ± 8 years; 73% males; forced vital capacity: 2 ± 0.8 L, 49 ± 13% predicted; diffusing capacity of carbon monoxide: 9.3 ± 4 mL/min/mm Hg, 51 ± 20% predicted) and 12 healthy age and gender-matched controls (56 ± 9.5 years; 50% males) were included. Compared with controls, people with ILD had a smaller CSA of rectus femoris (7.6 ± 2.1 vs 9.4 ± 2.4 cm(2) ; P = 0.03) and lower strength of knee extensors (119 ± 35 vs 147 ± 39 Nm; P = 0.02) and plantarflexors (37 ± 19 vs 50 ± 15 Nm; P = 0.02), but not of biceps. Individuals with ILD also had impaired performance on all functional tests (P < 0.02). Moderate correlations were found between rectus femoris CSA and knee extensor strength (r = 0.63; P < 0.01) and biceps thickness and elbow flexor strength (r = 0.78; P < 0.01) in the ILD group. CONCLUSIONS Individuals with advanced ILD presented with lower limb muscle atrophy and weakness. Future studies should evaluate the effectiveness of exercise training on muscle function in advanced ILD.
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Affiliation(s)
- Polyana Mendes
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
| | - Lisa Wickerson
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.,Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Denise Helm
- Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Tania Janaudis-Ferreira
- Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.,Respiratory Medicine, West Park Healthcare Centre, Toronto, Ontario, Canada
| | - Dina Brooks
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada
| | - Lianne G Singer
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Sunita Mathur
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada
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714
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Mendes P, Wickerson L, Helm D, Janaudis-Ferreira T, Brooks D, Singer LG, Mathur S. Skeletal muscle atrophy in advanced interstitial lung disease. Respirology 2015. [PMID: 26081374 DOI: 10.111/resp.12571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVE A limited number of studies examine skeletal muscle dysfunction in individuals with interstitial lung disease (ILD). We compared upper and lower limb muscle size and strength in individuals with advanced ILD with healthy controls. Second, the relationships of muscle size to muscle strength and function were explored. METHODS Individuals with advanced ILD listed for lung transplant and healthy control subjects were studied. B-mode ultrasound was performed to assess cross-sectional area (CSA) of rectus femoris and thickness of gastrocnemius and soleus and biceps brachii. Subjects performed isometric muscle strength testing, Short Physical Performance Battery, Timed Up and Go, and Unsupported Upper Limb Exercise Test. RESULTS Twenty-six individuals with advanced ILD (61 ± 8 years; 73% males; forced vital capacity: 2 ± 0.8 L, 49 ± 13% predicted; diffusing capacity of carbon monoxide: 9.3 ± 4 mL/min/mm Hg, 51 ± 20% predicted) and 12 healthy age and gender-matched controls (56 ± 9.5 years; 50% males) were included. Compared with controls, people with ILD had a smaller CSA of rectus femoris (7.6 ± 2.1 vs 9.4 ± 2.4 cm(2) ; P = 0.03) and lower strength of knee extensors (119 ± 35 vs 147 ± 39 Nm; P = 0.02) and plantarflexors (37 ± 19 vs 50 ± 15 Nm; P = 0.02), but not of biceps. Individuals with ILD also had impaired performance on all functional tests (P < 0.02). Moderate correlations were found between rectus femoris CSA and knee extensor strength (r = 0.63; P < 0.01) and biceps thickness and elbow flexor strength (r = 0.78; P < 0.01) in the ILD group. CONCLUSIONS Individuals with advanced ILD presented with lower limb muscle atrophy and weakness. Future studies should evaluate the effectiveness of exercise training on muscle function in advanced ILD.
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Affiliation(s)
- Polyana Mendes
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
| | - Lisa Wickerson
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.,Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Denise Helm
- Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Tania Janaudis-Ferreira
- Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada.,Respiratory Medicine, West Park Healthcare Centre, Toronto, Ontario, Canada
| | - Dina Brooks
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada
| | - Lianne G Singer
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Toronto Lung Transplant Program, Toronto, Ontario, Canada
| | - Sunita Mathur
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada.,Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada
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715
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Abstract
INTRODUCTION Histone deacetylases (HDACs) have been implicated in neurogenic muscle atrophy, but the mechanisms by which HDAC inhibitors might have beneficial effects are not defined. METHODS We used sciatic nerve crush to determine the effect of butyrate on denervation-induced gene expression and oxidative stress. RESULTS Butyrate treatment initiated 3 weeks before injury and continued 1 week after injury increases histone acetylation and reduces muscle atrophy after nerve crush. Butyrate delivered only after nerve crush similarly prevented muscle atrophy. Butyrate had no effect on the increase in histone deacetylase 4 (HDAC4) protein levels following nerve crush but prevented the increase in expression of myogenin, MuRF1, and atrogin-1. Butyrate did not affect mitochondrial reactive oxygen species production, but it increased antioxidant enzyme activity, reduced proteasome activity, and reduced oxidative damage following nerve injury. CONCLUSIONS These data suggest that HDAC inhibitors are promising pharmacological agents for treating neurogenic muscle atrophy. Muscle Nerve 52: 859-868, 2015.
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Affiliation(s)
- Michael E Walsh
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Arunabh Bhattacharya
- Department of Cellular and Structural Biology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.,Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Yuhong Liu
- Barshop Institute for Longevity and Aging Studies, San Antonio, Texas, USA
| | - Holly Van Remmen
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Oklahoma City, Oklahoma, 73104, USA
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716
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Liu ZJ, Rafferty KL, Ye W, Herring SW. Differential response of pig masseter to botulinum neurotoxin serotypes a and b. Muscle Nerve 2015; 52:88-93. [PMID: 26039454 DOI: 10.1002/mus.24492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 10/01/2014] [Accepted: 10/15/2014] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Pigs respond to direct administration of botulinum neurotoxins (BoNTs), although they are resistant to botulism. The human masseter is frequently targeted for BoNT therapy. We aimed to understand how BoNT affects chewing by injecting porcine masseters. METHODS One masseter of minipigs was injected with BoNT serotype A or B at doses comparable to those used in humans. Masticatory function was evaluated electromyographically. Muscle force was measured during tetany. Four weeks after injection, strain gauges affixed to the mandible assessed bone strain during chewing. Masseter mass and fiber diameter were measured after euthanasia. RESULTS BoNT-A had no measurable effect. In contrast, BoNT-B reduced electrical activity and muscle force, producing substantial asymmetry between injected and uninjected muscles. CONCLUSIONS The pig masseter is highly resistant to direct injection of BoNT-A, but it is affected by BoNT-B.
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Affiliation(s)
- Zi-Jun Liu
- Department of Orthodontics, University of Washington, Box 357446, Seattle, WA, 98195-7446, USA
| | - Katherine L Rafferty
- Department of Orthodontics, University of Washington, Box 357446, Seattle, WA, 98195-7446, USA
| | - Wenmin Ye
- Department of Orthodontics, University of Washington, Box 357446, Seattle, WA, 98195-7446, USA.,Department of Stomatology, No. 451 Hospital of PLA, Xi'an, P.R. China
| | - Susan W Herring
- Department of Orthodontics, University of Washington, Box 357446, Seattle, WA, 98195-7446, USA
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717
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Chen D, Wang Y, Chin ER. Activation of the endoplasmic reticulum stress response in skeletal muscle of G93A*SOD1 amyotrophic lateral sclerosis mice. Front Cell Neurosci 2015; 9:170. [PMID: 26041991 PMCID: PMC4435075 DOI: 10.3389/fncel.2015.00170] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/16/2015] [Indexed: 12/14/2022] Open
Abstract
Mutations in Cu/Zn superoxide dismutase (SOD1) are one of the genetic causes of Amyotrophic Lateral Sclerosis (ALS). Although the primary symptom of ALS is muscle weakness, the link between SOD1 mutations, cellular dysfunction and muscle atrophy and weakness is not well understood. The purpose of this study was to characterize cellular markers of ER stress in skeletal muscle across the lifespan of G93A*SOD1 (ALS-Tg) mice. Muscles were obtained from ALS-Tg and age-matched wild type (WT) mice at 70d (pre-symptomatic), 90d and 120–140d (symptomatic) and analyzed for ER stress markers. In white gastrocnemius (WG) muscle, ER stress sensors PERK and IRE1α were upregulated ~2-fold at 70d and remained (PERK) or increased further (IRE1α) at 120–140d. Phospho-eIF2α, a downstream target of PERK and an inhibitor of protein translation, was increased by 70d and increased further to 12.9-fold at 120–140d. IRE1α upregulation leads to increased splicing of X-box binding protein 1 (XBP-1) to the XBP-1s isoform. XBP-1s transcript was increased at 90d and 120–140d indicating activation of IRE1α signaling. The ER chaperone/heat shock protein Grp78/BiP was upregulated 2-fold at 70d and 90d and increased to 6.1-fold by 120–140d. The ER-stress-specific apoptotic signaling protein CHOP was upregulated 2-fold at 70d and 90d and increased to 13.3-fold at 120–140d indicating progressive activation of an apoptotic signal in muscle. There was a greater increase in Grp78/BiP and CHOP in WG vs. the more oxidative red gastrocnemius (RG) ALS-Tg at 120–140d indicating greater ER stress and apoptosis in fast glycolytic muscle. These data show that the ER stress response is activated in skeletal muscle of ALS-Tg mice by an early pre-symptomatic age and increases with disease progression. These data suggest a mechanism by which myocellular ER stress leads to reduced protein translation and contributes to muscle atrophy and weakness in ALS.
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Affiliation(s)
- Dapeng Chen
- School of Public Health, University of Maryland MD, USA
| | - Yan Wang
- Proteomics Core Facility, College of Computer, Mathematics and Natural Sciences, University of Maryland MD, USA
| | - Eva R Chin
- School of Public Health, University of Maryland MD, USA
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718
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Mei Z, Zhang D, Hu B, Wang J, Shen X, Xiao W. FBXO32 Targets c-Myc for Proteasomal Degradation and Inhibits c-Myc Activity. J Biol Chem 2015; 290:16202-14. [PMID: 25944903 DOI: 10.1074/jbc.m115.645978] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Indexed: 11/06/2022] Open
Abstract
FBXO32 (MAFbx/Atrogin-1) is an E3 ubiquitin ligase that is markedly up-regulated in muscle atrophy. Although some data indicate that FBXO32 may play an important role in tumorigenesis, the molecular mechanism of FBXO32 in tumorigenesis has been poorly understood. Here, we present evidence that FBXO32 targets the oncogenic protein c-Myc for ubiquitination and degradation through the proteasome pathway. Phosphorylation of c-Myc at Thr-58 and Ser-62 is dispensable for FBXO32 to induce c-Myc degradation. Mutation of the lysine 326 in c-Myc reduces c-Myc ubiquitination and prevents the c-Myc degradation induced by FBXO32. Furthermore, overexpression of FBXO32 suppresses c-Myc activity and inhibits cell growth, but knockdown of FBXO32 enhances c-Myc activity and promotes cell growth. Finally, we show that FBXO32 is a direct downstream target of c-Myc, highlighting a negative feedback regulation loop between c-Myc and FBXO32. Thus, FBXO32 may function by targeting c-Myc. This work explains the function of FBXO32 and highlights its mechanisms in tumorigenesis.
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Affiliation(s)
- Zhichao Mei
- From the Key Laboratory of Aquatic Biodiversity and Conservation and
| | - Dawei Zhang
- From the Key Laboratory of Aquatic Biodiversity and Conservation and
| | - Bo Hu
- From the Key Laboratory of Aquatic Biodiversity and Conservation and
| | - Jing Wang
- From the Key Laboratory of Aquatic Biodiversity and Conservation and
| | - Xian Shen
- the First Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Wuhan Xiao
- From the Key Laboratory of Aquatic Biodiversity and Conservation and the State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China and
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719
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Ham DJ, Kennedy TL, Caldow MK, Chee A, Lynch GS, Koopman R. Citrulline does not prevent skeletal muscle wasting or weakness in limb-casted mice. J Nutr 2015; 145:900-6. [PMID: 25740910 DOI: 10.3945/jn.114.203737] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 01/20/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Increasing arginine (Arg) availability reduces atrophy in cultured skeletal muscle cells. Supplementation with its metabolic precursor citrulline (Cit) is more effective at improving skeletal muscle Arg concentrations. OBJECTIVE We tested the hypothesis that Cit supplementation would attenuate skeletal muscle atrophy and loss of function during hindlimb immobilization in mice. METHODS Male C57BL/6JArc mice underwent 14 d of unilateral hindlimb immobilization/plaster casting and were supplemented with ~0.81 g Cit · kg⁻¹ · d⁻¹ (CIT group) or Ala (ALA group) mixed into their food. The uncasted contralateral limb (internal control) and an uncasted group (CON) served as controls. Muscle atrophy was evaluated with mass, fiber area, and in situ muscle function. RESULTS Tibialis anterior (TA) muscle mass [ALA: 37.6 ± 0.92 mg; CIT: 38.3 ± 1.25 mg] and peak tetanic force (ALA: 1150 ± 38.5 mN; CIT: 1150 ± 52.0 mN) were lower (P < 0.001) in the ALA (53.9 ± 0.42 mg) and CIT (1760 ± 28.5 mN) groups than in the CON group. No difference was found between ALA and CIT groups for TA mass, fiber area, or peak force. The mRNA expression of the nitric oxide synthase 2, inducible (Nos2; ~15-fold) and B-cell chronic lymphoid leukemia/lymphoma 2/adenovirus E1B 19 kDa interacting protein 3 (Bnip3; ~17-fold) genes and the ratio of microtubule-associated protein light chain 3BII to 3BI (LC3BII:LC3BI) (50.5% ± 17.7%) were higher (P < 0.05) in the ALA group than in the CON group, suggesting increased autophagy. In the CIT group, Bnip3 mRNA was lower (-70%; P < 0.05) and Nos2 mRNA tended to be lower (-45%; P = 0.05) than in the ALA group, whereas LC3BII:LC3BI was not different from the CON group. CONCLUSIONS Cit treatment of male mice did not affect therapeutically relevant outcome measures such as skeletal muscle mass and peak muscle force after 14 d of hindlimb immobilization.
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Affiliation(s)
- Daniel J Ham
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
| | - Tahnee L Kennedy
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
| | - Marissa K Caldow
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
| | - Annabel Chee
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
| | - Gordon S Lynch
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
| | - René Koopman
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Parkville, Australia
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720
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van der Sluijs MJ, van Ouwerkerk WJR, van der Sluijs JA, van Royen BJ. Elbow Flexion Contractures in Childhood in Obstetric Brachial Plexus Lesions: A Longitudinal Study of 20 Neurosurgically Reconstructed Infants with 8-Year Follow-up. J Brachial Plex Peripher Nerve Inj 2015; 10:e15-e22. [PMID: 27917234 DOI: 10.1055/s-0035-1549368] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 02/19/2015] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE Little knowledge exists on the development of elbow flexion contractures in children with obstetrical brachial plexus lesion (OBPL). This study aims to evaluate the prognostic significance of several neuromuscular parameters in infants with OBPL regarding the later development of elbow flexion contractures. METHODS Twenty infants with OBPL with insufficient signs of recovery in the first months of life who were neurosurgically reconstructed were included. At a mean age of 4.6 months, the following neuromuscular parameters were assessed: existence of flexion contractures, cross-sectional area (CSA) of upper arm muscles on MRI, Narakas classification, EMG results, and elbow muscle function using the Gilbert score. In childhood at follow-up at mean age of 7.7 years, we measured the amount of flexion contractures and the upper arm peak force (Newton). Statistical analysis is used to assess relations between these parameters. RESULTS Flexion contractures of greater than 10 degrees occurred in 55% of our patient group. The relation between the parameters in infancy and the flexion contractures in childhood is almost nonexistent. Only the Narakas classification was related to the development of flexion contractures in childhood (p = 0.006). Infant muscle CSA is related to childhood peak muscle force. CONCLUSION The role of infancy upper arm muscle hypotrophy/hypertrophy, reinnervation, and early elbow muscle function in the development of childhood elbow contractures remains unclear. In this cohort prediction of childhood flexion, contractures were not possible using infancy neuromuscular parameters. We suggest that contractures might be an adaptive process to optimize residual muscle function.
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Affiliation(s)
| | | | | | - Barend J van Royen
- Department of Orthopaedic Surgery, VU University Medical Centre, Amsterdam, The Netherlands
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721
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Bamman MM, Ferrando AA, Evans RP, Stec MJ, Kelly NA, Gruenwald JM, Corrick KL, Trump JR, Singh JA. Muscle inflammation susceptibility: a prognostic index of recovery potential after hip arthroplasty? Am J Physiol Endocrinol Metab 2015; 308:E670-9. [PMID: 25670829 PMCID: PMC4398830 DOI: 10.1152/ajpendo.00576.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/03/2015] [Indexed: 12/25/2022]
Abstract
While elective total hip arthroplasty (THA) for end-stage osteoarthritis (OA) improves pain, mobility function, and quality of life in most cases, a large proportion of patients suffer persistent muscle atrophy, pain, and mobility impairment. Extensive skeletal muscle damage is unavoidable in these surgical procedures, and it stands to reason that poor recovery and long-term mobility impairment among some individuals after THA is linked to failed muscle regeneration and regrowth following surgery and that local muscle inflammation susceptibility (MuIS) is a major contributing factor. Here we present results of two integrated studies. In study 1, we compared muscle inflammation and protein metabolism signaling in elective THA (n=15) vs. hip fracture/trauma (HFX; n=11) vs. nonsurgical controls (CON; n=19). In study 2, we compared two subgroups of THA patients dichotomized into MuIS⁺ (n=7) or MuIS⁻ (n=7) based on muscle expression of TNF-like weak inducer of apoptosis (TWEAK) receptor (Fn14). As expected, HFX demonstrated overt systemic and local muscle inflammation and hypermetabolism. By contrast, no systemic inflammation was detected in elective THA patients; however, local muscle inflammation in the perioperative limb was profound in MuIS⁺ and was accompanied by suppressed muscle protein synthesis compared with MuIS⁻. Muscle from the contralateral limb of MuIS⁺ was unaffected, providing evidence of a true inflammation susceptibility localized to the muscle surrounding the hip with end-stage OA. We suggest MuIS status assessed at the time of surgery may be a useful prognostic index for muscle recovery potential and could therefore provide the basis for a personalized approach to postsurgery rehabilitation.
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MESH Headings
- Arkansas
- Arthroplasty, Replacement, Hip/adverse effects
- Arthroplasty, Replacement, Hip/rehabilitation
- Biomarkers/metabolism
- Biopsy, Needle
- Cytokines/blood
- Disease Susceptibility
- Early Diagnosis
- Female
- Hospitals, University
- Humans
- Male
- Middle Aged
- Myositis/diagnosis
- Myositis/etiology
- Myositis/immunology
- Myositis/metabolism
- Osteoarthritis, Hip/physiopathology
- Osteoarthritis, Hip/rehabilitation
- Osteoarthritis, Hip/surgery
- Outpatient Clinics, Hospital
- Postoperative Complications/diagnosis
- Postoperative Complications/etiology
- Postoperative Complications/immunology
- Postoperative Complications/metabolism
- Precision Medicine
- Predictive Value of Tests
- Prognosis
- Quadriceps Muscle/immunology
- Quadriceps Muscle/metabolism
- Quadriceps Muscle/pathology
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/metabolism
- Reoperation/adverse effects
- Reoperation/rehabilitation
- TWEAK Receptor
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Affiliation(s)
- Marcas M Bamman
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama; Univeristy of Alabama at Birmingham Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Comprehensive Arthritis, Musculoskeletal, and Autoimmunity Center, University of Alabama at Birmingham, Birmingham, Alabama; Geriatric Research, Education, and Clinical Center, Birmingham Veterans Affairs Medical Center, Birmingham, Alabama;
| | - Arny A Ferrando
- Department of Geriatrics and Center for Translational Research in Aging and Longevity, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Richard P Evans
- Department of Orthopedic Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Michael J Stec
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama; Univeristy of Alabama at Birmingham Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Neil A Kelly
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama; Univeristy of Alabama at Birmingham Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Johannes M Gruenwald
- Department of Trauma Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Katie L Corrick
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jesse R Trump
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jasvinder A Singh
- Division of Clinical Immunology and Rheumatology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Univeristy of Alabama at Birmingham Center for Exercise Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Comprehensive Arthritis, Musculoskeletal, and Autoimmunity Center, University of Alabama at Birmingham, Birmingham, Alabama; Medicine Service, Birmingham Veterans Affairs Medical Center, Birmingham, Alabama; and Research Collaborator, Mayo Clinic College of Medicine, Rochester, Minnesota
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722
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Abstract
Glucocorticoids play a major role in the development of muscle atrophy in various medical conditions, such as cancer, burn injury, and sepsis, by inhibiting insulin signaling. In this study, we report a new pathway in which glucocorticoids reduce the levels of upstream insulin signaling components by downregulating the transcription of the gene encoding caveolin-1 (CAV1), a scaffolding protein present in the caveolar membrane. Treatment with the glucocorticoid dexamethasone (DEX) decreased CAV1 protein and Cav1 mRNA expression, with a concomitant reduction in insulin receptor alpha (IRα) and IR substrate 1 (IRS1) levels in C2C12 myotubes. On the basis of the results of promoter analysis using deletion mutants and site-directed mutagenesis a negative glucocorticoid-response element in the regulatory region of the Cav1 gene was identified, confirming that Cav1 is a glucocorticoid-target gene. Cav1 knockdown using siRNA decreased the protein levels of IRα and IRS1, and overexpression of Cav1 prevented the DEX-induced decrease in IRα and IRS1 proteins, demonstrating a causal role of Cav1 in the inhibition of insulin signaling. Moreover, injection of adenovirus expressing Cav1 into the gastrocnemius muscle of mice prevented DEX-induced atrophy. These results indicate that CAV1 is a critical regulator of muscle homeostasis, linking glucocorticoid signaling to the insulin signaling pathway, thereby providing a novel target for the prevention of glucocorticoid-induced muscle atrophy.
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Affiliation(s)
- Young Hoon Son
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Seok-Jin Lee
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Ki-Baek Lee
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Jin-Haeng Lee
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Eui Man Jeong
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Sun Gun Chung
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - Sang-Chul Park
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
| | - In-Gyu Kim
- Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea Department of Biochemistry and Molecular BiologyInstitute of Human-Environment Interface BiologyDepartment of Rehabilitation MedicineSeoul National University College of Medicine, 103 Daehak-ro, Jongno-Gu, Seoul 110-799, Korea
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723
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Deng C, Wang P, Zhang X, Wang Y. Short-term, daily exposure to cold temperature may be an efficient way to prevent muscle atrophy and bone loss in a microgravity environment. Life Sci Space Res (Amst) 2015; 5:1-5. [PMID: 25821722 PMCID: PMC4374360 DOI: 10.1016/j.lssr.2015.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Microgravity induces less pressure on muscle/bone, which is a major reason for muscle atrophy as well as bone loss. Currently, physical exercise is the only countermeasure used consistently in the U.S. human space program to counteract the microgravity-induced skeletal muscle atrophy and bone loss. However, the routinely almost daily time commitment is significant and represents a potential risk to the accomplishment of other mission operational tasks. Therefore, development of more efficient exercise programs (with less time) to prevent astronauts from muscle atrophy and bone loss are needed. Consider the two types of muscle contraction: exercising forces muscle contraction and prevents microgravity-induced muscle atrophy/bone loss, which is a voluntary response through the motor nervous system; and cold temperature exposure-induced muscle contraction is an involuntary response through the vegetative nervous system, we formed a new hypothesis. The main purpose of this pilot study was to test our hypothesis that exercise at 4 °C is more efficient than at room temperature to prevent microgravity-induced muscle atrophy/bone loss and, consequently reduces physical exercise time. Twenty mice were divided into two groups with or without daily short-term (10 min × 2, at 12 h interval) cold temperature (4 °C) exposure for 30 days. The whole bodyweight, muscle strength and bone density were measured after terminating the experiments. The results from the one-month pilot study support our hypothesis and suggest that it would be reasonable to use more mice, in a microgravity environment and observe for a longer period to obtain a conclusion. We believe that the results from such a study will help to develop efficient exercise, which will finally benefit astronauts' heath and NASA's missions.
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Affiliation(s)
| | | | | | - Ya Wang
- Correspondence to: Ya Wang, M.D., Ph.D., Professor and Director, Division of Experimental Radiation Oncology, Department of Radiation Oncology, Winship Cancer Institute of Emory University, 1365 Clifton Road NE, Room C5090, Atlanta, GA 30322, Tel: 404-778-1832, Fax: 404-778-1750, , http://radiationoncology.emory.edu/
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724
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Nakao R, Yamamoto S, Horikawa K, Yasumoto Y, Nikawa T, Mukai C, Oishi K. Atypical expression of circadian clock genes in denervated mouse skeletal muscle. Chronobiol Int 2015; 32:486-96. [PMID: 25798696 DOI: 10.3109/07420528.2014.1003350] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The central circadian clock in the suprachiasmatic nucleus of the hypothalamus synchronizes peripheral clocks through neural and humoral signals in most mammalian tissues. Here, we analyzed the effects of unilateral sciatic denervation on the expression of circadian clock- and clock-controlled genes in the gastrocnemius muscles of mice twice per day on days 0, 3, 7, 9, 11 and 14 after denervation and six times on each of days 7 and 28 after denervation to assess the regulation mechanism of the circadian clock in skeletal muscle. Sciatic denervation did not affect systemic circadian rhythms since core body temperature (Day 7), corticosterone secretion (Days 7 and 28), and hepatic clock gene expression remained intact (Days 7 and 28). Expression levels of most circadian clock-related genes such as Arntl, Per1, Rora, Nr1d1 and Dbp were reduced in accordance with the extent of muscle atrophy, although circadian Per2 expression was significantly augmented (Day 28). Cosinor analysis revealed that the circadian expression of Arntl (Days 7 and 28) and Dbp (Day 28) was phase advanced in denervated muscle. The mRNA expression of Clock was significantly increased in denervated muscle on Day 3 when the severe atrophy was absent, and it was not affected by atrophic progression for 28 days. Sciatic denervation did not affect the expression of these genes in the contralateral muscle (Days 7 and 28), suggesting that humoral changes were not involved in denervation-induced muscle clock disruption. We then analyzed genome-wide gene expression using microarrays to determine the effects of disrupting the molecular clock in muscle on circadian rhythms at Day 7. Among 478 circadian genes, 313 lost rhythmicity in the denervated muscles. These denervation-sensitive genes included the lipid metabolism-related genes, Nrip1, Bbs1, Ptgis, Acot1, Scd2, Hpgd, Insig1, Dhcr24, Ldlr and Mboat1. Our findings revealed that sciatic denervation disrupts the circadian expression of clock and clock-controlled genes either directly or indirectly via muscle atrophy in the gastrocnemius muscles of mice in a gene-specific manner.
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Affiliation(s)
- Reiko Nakao
- Biological Clock Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba, Ibaraki , Japan
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725
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Sakakima H, Yoshida Y. The effect of short duration static stretching and reinnervation on the recovery of denervated soleus muscle in the rat. J Jpn Phys Ther Assoc 2015; 5:13-8. [PMID: 25792925 DOI: 10.1298/jjpta.5.13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2001] [Accepted: 01/12/2002] [Indexed: 11/23/2022]
Abstract
Denervation elicits profound alterations in the morphometry of the skeletal muscle. There is evidence that the increased mechanical load placed upon the muscle via rhythmic stretching attenuates denervation induced alterations in muscle morphology. To investigate the effect of short duration static stretching (40 min/day) for denervated and reinnervated muscle, a histochemical study was performed on the soleus muscle of the rat. Twenty-one eight-week-old female Wistar rats were used. Partial denervation was carried out by locally freezing the proximal root of the sciatic nerve innervating the soleus muscle. Contralateral hindlimbs were untreated and served as control. Axonal degeneration was evident within the sciatic nerve following freezing, although variable amounts of damage were observed and thin nerve fibers were observed at 3 weeks. No clear difference of morphological change of the sciatic nerve was observed in the short duration static stretching groups (group S) or the non-stretching groups (group D). The wet weight of the denervated soleus muscles progressively declined to a minimum at 2 weeks after injury (group D, 50.8 ± 8.9%; group S, 61.3 ± 4.2%) and began to reverse in the following 3 weeks. Muscle wet weight for short duration static stretching groups similarly decreased and began to reverse in the following 3 weeks. The muscle fiber cross-sectional area also similarly changed with the muscle wet weight. The type II fiber ratios of the denervated sides were consistently higher than the control levels. In non-stretching groups, type II fibers had increased by 3 weeks after denervation (49.4%), whereas type II fiber ratios of the short duration static stretching groups decreased after 3 weeks (31.3%). These data suggests that mechanical stimuli provided by short duration static stretching can prevent the atrophy of the denervated muscle over a short period. In addition, it was indicated that short duration static stretching affected the reinnervated muscle fiber type composition. However, the reinnervation took the crucial role of recovering from the atrophy and composing the integrity of the soleus muscles.
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Affiliation(s)
- Harutoshi Sakakima
- School of Health Sciences, Faculty of Medicine, Kagoshima University, 8-35-1, Sakuragaoka, Kagoshima 890-8506, Japan
| | - Yoshihiro Yoshida
- School of Health Sciences, Faculty of Medicine, Kagoshima University, 8-35-1, Sakuragaoka, Kagoshima 890-8506, Japan
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726
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Ribeiro CB, Christofoletti DC, Pezolato VA, de Cássia Marqueti Durigan R, Prestes J, Tibana RA, Pereira ECL, de Sousa Neto IV, Durigan JLQ, da Silva CA. Leucine minimizes denervation-induced skeletal muscle atrophy of rats through akt/mtor signaling pathways. Front Physiol 2015; 6:73. [PMID: 25852565 PMCID: PMC4364154 DOI: 10.3389/fphys.2015.00073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 02/20/2015] [Indexed: 11/20/2022] Open
Abstract
The aim of the present study was to evaluate the effect of leucine treatment (0.30 mM) on muscle weight and signaling of myoproteins related to synthesis and degradation pathways of soleus muscle following seven days of complete sciatic nerve lesion. Wistar rats (n = 24) of 3–4 months of age (192 ± 23 g) were used. The animals were randomly distributed into four experimental groups (n = 6/group): control, treated with leucine (L), denervated (D) and denervated treated with leucine (DL). Dependent measures were proteins levels of AKT, AMPK, mTOR, and ACC performed by Western blot. Leucine induced a reduction in the phosphorylation of AMPK (p < 0.05) by 16% in the L and by 68% in the DL groups as compared with control group. Denervation increased AMPK by 24% in the D group as compared with the control group (p < 0.05). AKT was also modulated by denervation and leucine treatment, highlighted by the elevation of AKT phosphorylation in the D (65%), L (98%) and DL (146%) groups as compared with the control group (p < 0.05). AKT phosphorylation was 49% higher in the D group as compared with the DL group. Furthermore, denervation decreased mTOR phosphorylation by 29% in the D group as compared with the control group. However, leucine treatment induced an increase of 49% in the phosphorylation of mTOR in the L group as compared with the control group, and an increase of 154% in the DL as compared with the D group (p < 0.05). ACC phosphorylation was 20% greater in the D group than the control group. Furthermore, ACC in the soleus was 22% lower in the in the L group and 50% lower in the DL group than the respective control group (p < 0.05). In conclusion, leucine treatment minimized the deleterious effects of denervation on rat soleus muscle by increasing anabolic (AKT and mTOR) and decreasing catabolic (AMPK) pathways. These results may be interesting for muscle recovery following acute denervation, which may contribute to musculoskeletal rehabilitation after denervation.
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Affiliation(s)
- Carolina B Ribeiro
- Programa de Pós-graduação em Ciências do Movimento Humano, Methodist University of Piracicaba, UNIMEP Piracicaba, Brazil
| | - Daiane C Christofoletti
- Programa de Pós-graduação em Ciências do Movimento Humano, Methodist University of Piracicaba, UNIMEP Piracicaba, Brazil
| | - Vitor A Pezolato
- Programa de Pós-graduação em Ciências do Movimento Humano, Methodist University of Piracicaba, UNIMEP Piracicaba, Brazil
| | | | - Jonato Prestes
- Graduate Program of Physical Education, Catholic University of Brasília Brasilia, Brazil
| | - Ramires A Tibana
- Graduate Program of Physical Education, Catholic University of Brasília Brasilia, Brazil
| | - Elaine C L Pereira
- Graduate Program of Science and Technology of Health, University of Brasília Brasilia, Brazil
| | - Ivo V de Sousa Neto
- Graduate Program of Physical Education, Catholic University of Brasília Brasilia, Brazil
| | - João L Q Durigan
- Graduate Program of Science and Technology of Health, University of Brasília Brasilia, Brazil ; Graduate Program of Physical Education, University of Brasília Brasilia, Brazil
| | - Carlos A da Silva
- Programa de Pós-graduação em Ciências do Movimento Humano, Methodist University of Piracicaba, UNIMEP Piracicaba, Brazil
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727
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Martin KS, Blemker SS, Peirce SM. Agent-based computational model investigates muscle-specific responses to disuse-induced atrophy. J Appl Physiol (1985) 2015; 118:1299-309. [PMID: 25722379 DOI: 10.1152/japplphysiol.01150.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/20/2015] [Indexed: 01/27/2023] Open
Abstract
Skeletal muscle is highly responsive to use. In particular, muscle atrophy attributable to decreased activity is a common problem among the elderly and injured/immobile. However, each muscle does not respond the same way. We developed an agent-based model that generates a tissue-level skeletal muscle response to disuse/immobilization. The model incorporates tissue-specific muscle fiber architecture parameters and simulates changes in muscle fiber size as a result of disuse-induced atrophy that are consistent with published experiments. We created simulations of 49 forelimb and hindlimb muscles of the rat by incorporating eight fiber-type and size parameters to explore how these parameters, which vary widely across muscles, influence sensitivity to disuse-induced atrophy. Of the 49 muscles modeled, the soleus exhibited the greatest atrophy after 14 days of simulated immobilization (51% decrease in fiber size), whereas the extensor digitorum communis atrophied the least (32%). Analysis of these simulations revealed that both fiber-type distribution and fiber-size distribution influence the sensitivity to disuse atrophy even though no single tissue architecture parameter correlated with atrophy rate. Additionally, software agents representing fibroblasts were incorporated into the model to investigate cellular interactions during atrophy. Sensitivity analyses revealed that fibroblast agents have the potential to affect disuse-induced atrophy, albeit with a lesser effect than fiber type and size. In particular, muscle atrophy elevated slightly with increased initial fibroblast population and increased production of TNF-α. Overall, the agent-based model provides a novel framework for investigating both tissue adaptations and cellular interactions in skeletal muscle during atrophy.
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Affiliation(s)
- Kyle S Martin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Silvia S Blemker
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia; Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia; Department of Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia;
| | - Shayn M Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia; Department of Ophthalmology, University of Virginia, Charlottesville, Virginia; Department of Plastic Surgery, University of Virginia, Charlottesville, Virginia
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728
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Davis ME, Korn MA, Gumucio JP, Harning JA, Saripalli AL, Bedi A, Mendias CL. Simvastatin reduces fibrosis and protects against muscle weakness after massive rotator cuff tear. J Shoulder Elbow Surg 2015; 24:280-7. [PMID: 25213828 DOI: 10.1016/j.jse.2014.06.048] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Revised: 06/14/2014] [Accepted: 06/27/2014] [Indexed: 02/01/2023]
Abstract
BACKGROUND Chronic rotator cuff tears are a common source of shoulder pain and disability, and patients with chronic cuff tears often have substantial weakness, fibrosis, inflammation, and fat accumulation. Identifying therapies to prevent the development of these pathologic processes will likely have a positive impact on clinical outcomes. Simvastatin is a drug with demonstrated anti-inflammatory and antifibrotic effects in many tissues but had not previously been studied in the context of rotator cuff tears. We hypothesized that after the induction of a massive supraspinatus tear, simvastatin would protect muscles from a loss of force production and fibrosis. METHODS We measured changes in muscle fiber contractility, histology, and biochemical markers of fibrosis and fatty infiltration in rats that received a full-thickness supraspinatus tear and were treated with either carrier alone or simvastatin. RESULTS Compared with vehicle-treated controls, simvastatin did not have an appreciable effect on muscle fiber size, but treatment did increase muscle fiber specific force by 20%. Simvastatin also reduced collagen accumulation by 50% but did not affect triglyceride content of muscles. Several favorable changes in the expression of genes and other markers of inflammation, fibrosis, and regeneration were also observed. CONCLUSIONS Simvastatin partially protected muscles from the weakness that occurs as a result of chronic rotator cuff tear. Fibrosis was also markedly reduced in simvastatin-treated animals. Whereas further studies are necessary, statin medication could potentially help improve outcomes for patients with rotator cuff tears.
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729
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Xing H, Zhou M, Assinck P, Liu N. Electrical stimulation influences satellite cell differentiation after sciatic nerve crush injury in rats. Muscle Nerve 2015; 51:400-11. [PMID: 24947716 DOI: 10.1002/mus.24322] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2014] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Electrical stimulation is often used to prevent muscle atrophy and preserve contractile function, but its effects on the satellite cell population after nerve injury are not well understood. In this study we aimed to determine whether satellite cell differentiation is affected by electrical stimulation after nerve crush. METHODS The sciatic nerves of Sprague-Dawley (SD) rats were crushed. Half of the injured rats received daily electrical stimulation of the gastrocnemius muscle, and the others did not. Tests for detecting paired box protein 7 (Pax7), myogenic differentiation antigen (MyoD), embryonic myosin heavy chain (eMyHC), and force production were performed 2, 4, and 6 weeks after injury. RESULTS More Pax7+/MyoD+ nuclei in stimulated muscles were observed than in non-stimulated muscles. eMyHC expression was elevated in stimulated muscles and correlated positively with enhanced force production. CONCLUSIONS Increased satellite cell differentiation is correlated with preserved muscle function in response to electrical stimulation after nerve injury.
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Affiliation(s)
- Huayi Xing
- Department of Rehabilitation Medicine, Peking University Third Hospital, 49 North Garden Road, Beijing, 100191, PR China
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730
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Sollanek KJ, Smuder AJ, Wiggs MP, Morton AB, Koch LG, Britton SL, Powers SK. Role of intrinsic aerobic capacity and ventilator-induced diaphragm dysfunction. J Appl Physiol (1985) 2015; 118:849-57. [PMID: 25571991 DOI: 10.1152/japplphysiol.00797.2014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/30/2014] [Indexed: 12/16/2022] Open
Abstract
Prolonged mechanical ventilation (MV) leads to rapid diaphragmatic atrophy and contractile dysfunction, which is collectively termed "ventilator-induced diaphragm dysfunction" (VIDD). Interestingly, endurance exercise training prior to MV has been shown to protect against VIDD. Further, recent evidence reveals that sedentary animals selectively bred to possess a high aerobic capacity possess a similar skeletal muscle phenotype to muscles from endurance trained animals. Therefore, we tested the hypothesis that animals with a high intrinsic aerobic capacity would naturally be afforded protection against VIDD. To this end, animals were selectively bred over 33 generations to create two divergent strains, differing in aerobic capacity: high-capacity runners (HCR) and low-capacity runners (LCR). Both groups of animals were subjected to 12 h of MV and compared with nonventilated control animals within the same strains. As expected, contrasted to LCR animals, the diaphragm muscle from the HCR animals contained higher levels of oxidative enzymes (e.g., citrate synthase) and antioxidant enzymes (e.g., superoxide dismutase and catalase). Nonetheless, compared with nonventilated controls, prolonged MV resulted in significant diaphragmatic atrophy and impaired diaphragm contractile function in both the HCR and LCR animals, and the magnitude of VIDD did not differ between strains. In conclusion, these data demonstrate that possession of a high intrinsic aerobic capacity alone does not afford protection against VIDD. Importantly, these results suggest that endurance exercise training differentially alters the diaphragm phenotype to resist VIDD. Interestingly, levels of heat shock protein 72 did not differ between strains, thus potentially representing an important area of difference between animals with intrinsically high aerobic capacity and exercise-trained animals.
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Affiliation(s)
- Kurt J Sollanek
- Department of Applied Physiology and Kinesiology, Center for Exercise Science, University of Florida, Gainesville, Florida; and
| | - Ashley J Smuder
- Department of Applied Physiology and Kinesiology, Center for Exercise Science, University of Florida, Gainesville, Florida; and
| | - Michael P Wiggs
- Department of Applied Physiology and Kinesiology, Center for Exercise Science, University of Florida, Gainesville, Florida; and
| | - Aaron B Morton
- Department of Applied Physiology and Kinesiology, Center for Exercise Science, University of Florida, Gainesville, Florida; and
| | - Lauren G Koch
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan
| | - Steven L Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan
| | - Scott K Powers
- Department of Applied Physiology and Kinesiology, Center for Exercise Science, University of Florida, Gainesville, Florida; and
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731
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Schoser B. Muscle histology changes after short term vibration training in healthy controls. Acta Myol 2015; 34:133-8. [PMID: 27199541 PMCID: PMC4859078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In search for additional counter measures of muscle atrophy vibration exercise training may have substantial effort for patients with neuromuscular disorders. To cover safety aspects and obtain muscle morphology data, a pilot study was performed in eleven healthy men. Countermovement jump, squat jump, drop jump and one repetition maximum test (1RM) were performed on a force platform before and after a 6 week training period. No severe side effects were found. Repeated needle muscle biopsies of the vastus lateralis muscle revealed a selective pre- to post-training type-2 myofiber hypertrophy of up to 50 %. The hypertrophy factors were 160 and 310, for type-2 myofibers. The mechanography system showed a significant increase in the 1RM maximum weight lifted (pre: 111,8 kg ± 11,5; post: 140,9 kg ± 13,00; p < 0,001). Vibration exercise is a safe and effective technique which desires further approval as counter measure in different types of neuromuscular atrophy.
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Affiliation(s)
- Benedikt Schoser
- Address for correspondence: Benedikt Schoser, Friedrich-Baur-Institute, Department of Neurology,Ludwig Maximilians University Munich - Ziemssenstr. 1a -80336 Munich, Germany. E-mail: –muenchen.de
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732
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Papalia I, Ronchi G, Muratori L, Mazzucco A, Magaudda L, Geuna S. Direct muscle neurotization after end-to end and end-to-side neurorrhaphy: An experimental study in the rat forelimb model. Neural Regen Res 2014; 7:2273-8. [PMID: 25538749 PMCID: PMC4268728 DOI: 10.3969/j.issn.1673-5374.2012.29.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 07/10/2012] [Indexed: 01/09/2023] Open
Abstract
The need for the continuous research of new tools for improving motor function recovery after nerve injury is justified by the still often unsatisfactory clinical outcome in these patients. It has been previously shown that the combined use of two reconstructive techniques, namely end-to-side neurorrhaphy and direct muscle neurotization in the rat hindlimb model, can lead to good results in terms of skeletal muscle reinnervation. Here we show that, in the rat forelimb model, the combined use of direct muscle neurotization with either end-to-end or end-to-side neurorrhaphy to reinnervate the denervated flexor digitorum muscles, leads to muscle atrophy prevention over a long postoperative time lapse (10 months). By contrast, very little motor recovery (in case of end-to-end neurorrhaphy) and almost no motor recovery (in case of end-to-side neurorrhaphy) were observed in the grasping activity controlled by flexor digitorum muscles. It can thus be concluded that, at least in the rat, direct muscle neurotization after both end-to-end and end-to-side neurorrhaphy represents a good strategy for preventing denervation-related muscle atrophy but not for regaining the lost motor function.
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Affiliation(s)
- Igor Papalia
- Department of Biomorphology and Biotechnologies, University of Messina, Messina 98100, Italy
| | - Giulia Ronchi
- Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences, University of Turin, Torino 10043, Italy
| | - Luisa Muratori
- Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences, University of Turin, Torino 10043, Italy
| | - Alessandra Mazzucco
- Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences, University of Turin, Torino 10043, Italy
| | - Ludovico Magaudda
- Department of Biomorphology and Biotechnologies, University of Messina, Messina 98100, Italy
| | - Stefano Geuna
- Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences, University of Turin, Torino 10043, Italy
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733
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Roshanravan B, Patel KV, Robinson-Cohen C, de Boer IH, O'Hare AM, Ferrucci L, Himmelfarb J, Kestenbaum B. Creatinine clearance, walking speed, and muscle atrophy: a cohort study. Am J Kidney Dis 2014; 65:737-47. [PMID: 25542415 DOI: 10.1053/j.ajkd.2014.10.016] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 10/06/2014] [Indexed: 12/25/2022]
Abstract
BACKGROUND Chronic kidney disease is associated with malnutrition and inflammation. These processes may lead to loss of skeletal muscle and reduced physical performance. Associations of kidney function with muscle composition and longitudinal measures of physical performance are unknown. STUDY DESIGN Prospective cohort study. SETTING & PARTICIPANTS We evaluated 826 community-dwelling older adults enrolled in the Invecchiare in Chianti (InCHIANTI) Study who were free of baseline stroke or activities of daily living disability. PREDICTOR Baseline creatinine clearance (Clcr) based on 24-hour urine collection. OUTCOMES Cross-sectional and longitudinal trajectories of physical performance measured by 7-m usual gait speed, 400-m fast gait speed, and knee extension strength using isometric dynamometry. Calf muscle composition assessed by quantitative computed tomography. RESULTS Mean age of participants was 74 ± 7 (SD) years, with 183 having Clcr < 60 mL/min/1.73 m(2). After adjustment, each 10-mL/min/1.73 m(2) decrement in Clcr was associated with 0.01 (95% CI, 0.004-0.017) m/s slower 7-m usual walking speed and 0.008 (95% CI, 0.002-0.014) m/s slower 400-m walking speed. Each 10-mL/min/1.73 m(2) decrement in Clcr was associated with 28 (95% CI, 0.8-55) mm(2) lower muscle area and 0.15 (95% CI, 0.04-0.26) mg/cm(3) lower muscle density. After adjustment, lower Clcr was associated with slower mean 7-m (P=0.005) and 400-m (P=0.02) walk and knee extension strength (P=0.001) during the course of follow-up. During a mean follow-up of 7.1 ± 2.5 years, each 10-mL/min/1.73 m(2) lower baseline Clcr was associated with 0.024 (95% CI, 0.01-0.037) kg/y greater decline in knee strength. LIMITATIONS Single baseline measurement of Clcr and 3-year interval between follow-up visits may lead to nondifferential misclassification and attenuation of estimates. CONCLUSIONS Among older adults, lower Clcr is associated with muscle atrophy, reduced walking speed, and more rapid declines in lower-extremity strength over time.
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Affiliation(s)
- Baback Roshanravan
- Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Seattle, WA.
| | - Kushang V Patel
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA
| | - Cassianne Robinson-Cohen
- Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Seattle, WA
| | - Ian H de Boer
- Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Seattle, WA
| | - Ann M O'Hare
- Veterans Affairs Puget Sound Healthcare System, University of Washington, Seattle, WA
| | - Luigi Ferrucci
- Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD
| | - Jonathan Himmelfarb
- Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Seattle, WA
| | - Bryan Kestenbaum
- Division of Nephrology, Department of Medicine, University of Washington Kidney Research Institute, Seattle, WA
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734
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Santalla A, Munguía-Izquierdo D, Brea-Alejo L, Pagola-Aldazábal I, Díez-Bermejo J, Fleck SJ, Ara I, Lucia A. Feasibility of resistance training in adult McArdle patients: clinical outcomes and muscle strength and mass benefits. Front Aging Neurosci 2014; 6:334. [PMID: 25566067 PMCID: PMC4263173 DOI: 10.3389/fnagi.2014.00334] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/27/2014] [Indexed: 12/21/2022] Open
Abstract
We analyzed the effects of a 4-month resistance (weight lifting) training program followed by a 2-month detraining period in 7 adult McArdle patients (5 female) on: muscle mass (assessed by DXA), strength, serum creatine kinase (CK) activity and clinical severity. Adherence to training was ≥84% in all patients and no major contraindication or side effect was noted during the training or strength assessment sessions. The training program had a significant impact on total and lower extremities’ lean mass (P < 0.05 for the time effect), with mean values increasing with training by +855 g (95% confidence interval (CI): 30, 1679) and +547 g (95%CI: 116, 978), respectively, and significantly decreasing with detraining. Body fat showed no significant changes over the study period. Bench press and half-squat performance, expressed as the highest value of average muscle power (W) or force (N) in the concentric-repetition phase of both tests showed a consistent increase over the 4-month training period, and decreased with detraining. Yet muscle strength and power detraining values were significantly higher than pre-training values, indicating that a training effect was still present after detraining. Importantly, all the participants, with no exception, showed a clear gain in muscle strength after the 4-month training period, e.g., bench press: +52 W (95% CI: 13, 91); half-squat: +173 W (95% CI: 96, 251). No significant time effect (P > 0.05) was noted for baseline or post strength assessment values of serum CK activity, which remained essentially within the range reported in our laboratory for McArdle patients. All the patients changed to a lower severity class with training, such that none of them were in the highest disease severity class (3) after the intervention and, as such, they did not have fixed muscle weakness after training. Clinical improvements were retained, in all but one patient, after detraining, such that after detraining all patients were classed as class 1 for disease severity.
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Affiliation(s)
- Alfredo Santalla
- Department of Sports Sciences, Universidad Pablo de Olavide Seville, Spain ; Research Institute "i+12", Hospital 12 de Octubre Madrid, Spain
| | | | - Lidia Brea-Alejo
- Research Institute "i+12", Hospital 12 de Octubre Madrid, Spain ; Faculty of Sports Sciences, European University Madrid, Spain
| | - Itziar Pagola-Aldazábal
- Research Institute "i+12", Hospital 12 de Octubre Madrid, Spain ; Faculty of Sports Sciences, European University Madrid, Spain
| | - Jorge Díez-Bermejo
- Research Institute "i+12", Hospital 12 de Octubre Madrid, Spain ; Faculty of Sports Sciences, European University Madrid, Spain
| | - Steven J Fleck
- Department of Kinesiology, University of Wisconsin-Eau Claire Eau Claire, WI, USA
| | - Ignacio Ara
- GENUD Toledo Research Group, University of Castilla-La Mancha Toledo, Spain
| | - Alejandro Lucia
- Research Institute "i+12", Hospital 12 de Octubre Madrid, Spain ; School of Doctorate Studies and Research, Laboratory P-102, European University Madrid, Spain
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735
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Alway SE, Bennett BT, Wilson JC, Sperringer J, Mohamed JS, Edens NK, Pereira SL. Green tea extract attenuates muscle loss and improves muscle function during disuse, but fails to improve muscle recovery following unloading in aged rats. J Appl Physiol (1985) 2014; 118:319-30. [PMID: 25414242 DOI: 10.1152/japplphysiol.00674.2014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In this study we tested the hypothesis that green tea extract (GTE) would improve muscle recovery after reloading following disuse. Aged (32 mo) Fischer 344 Brown Norway rats were randomly assigned to receive either 14 days of hindlimb suspension (HLS) or 14 days of HLS followed by normal ambulatory function for 14 days (recovery). Additional animals served as cage controls. The rats were given GTE (50 mg/kg body wt) or water (vehicle) by gavage 7 days before and throughout the experimental periods. Compared with vehicle treatment, GTE significantly attenuated the loss of hindlimb plantaris muscle mass (-24.8% vs. -10.7%, P < 0.05) and tetanic force (-43.7% vs. -25.9%, P <0.05) during HLS. Although GTE failed to further improve recovery of muscle function or mass compared with vehicle treatment, animals given green tea via gavage maintained the lower losses of muscle mass that were found during HLS (-25.2% vs. -16.0%, P < 0.05) and force (-45.7 vs. -34.4%, P < 0.05) after the reloading periods. In addition, compared with vehicle treatment, GTE attenuated muscle fiber cross-sectional area loss in both plantaris (-39.9% vs. -23.9%, P < 0.05) and soleus (-37.2% vs. -17.6%) muscles after HLS. This green tea-induced difference was not transient but was maintained over the reloading period for plantaris (-45.6% vs. -21.5%, P <0.05) and soleus muscle fiber cross-sectional area (-38.7% vs. -10.9%, P <0.05). GTE increased satellite cell proliferation and differentiation in plantaris and soleus muscles during recovery from HLS compared with vehicle-treated muscles and decreased oxidative stress and abundance of the Bcl-2-associated X protein (Bax), yet this did not further improve muscle recovery in reloaded muscles. These data suggest that muscle recovery following disuse in aging is complex. Although satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is by itself insufficient to improve muscle recovery following a period of atrophy in old rats.
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Affiliation(s)
- Stephen E Alway
- Laboratory of Muscle Biology and Sarcopenia, Department of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; West Virginia Center for Clinical and Translational Science Institute, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia; and
| | - Brian T Bennett
- Laboratory of Muscle Biology and Sarcopenia, Department of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia; and
| | - Joseph C Wilson
- Laboratory of Muscle Biology and Sarcopenia, Department of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia; and
| | - Justin Sperringer
- Laboratory of Muscle Biology and Sarcopenia, Department of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia; and
| | - Junaith S Mohamed
- Laboratory of Muscle Biology and Sarcopenia, Department of Exercise Physiology, West Virginia University School of Medicine, Morgantown, West Virginia; Center for Cardiovascular and Respiratory Sciences, West Virginia University School of Medicine, Morgantown, West Virginia; and
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736
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Calvani R, Martone AM, Marzetti E, Onder G, Savera G, Lorenzi M, Serafini E, Bernabei R, Landi F. Pre-hospital dietary intake correlates with muscle mass at the time of fracture in older hip-fractured patients. Front Aging Neurosci 2014; 6:269. [PMID: 25477815 PMCID: PMC4236534 DOI: 10.3389/fnagi.2014.00269] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/19/2014] [Indexed: 01/16/2023] Open
Abstract
Background: Failure to meet an adequate dietary intake is involved in the pathogenesis of sarcopenia and osteoporosis, which in turn increase the risk for falls and fractures, respectively. Older people with hip fracture are often protein-malnourished at hospitalization. Whether low protein-energy intake is associated with muscle atrophy in hip-fractured patients is presently unknown. This information is necessary for the development of novel strategies to manage this especially vulnerable patient population. The aim of this study was, therefore, to explore the relationship between dietary intake and muscle mass in older hip-fractured patients. Methods: Analyses were conducted in hip-fractured elderly admitted to an orthopedic and trauma surgery ward (University Hospital). Muscle mass was estimated by bioelectrical impedance analysis within 24 h from admission. Dietary information was collected via 24-h dietary recall and nutrient intake calculated by a nutrition software. Results: Among 62 hip-fractured patients (mean age 84.6 ± 7.6 years, 84% women), the average energy intake was 929.2 ± 170.3 Kcal day−1, with higher values reported by men (1.046.8 ± 231.4 Kcal day−1) relative to women (906.5 ± 148.3 Kcal day−1; p = 0.01). Absolute and normalized protein intake was 50.0 ± 13.5 g day−1 and 0.88 ± 0.27 g kg (body weight)–1 day–1, respectively, with no gender differences. A positive correlation was determined between total energy intake and muscle mass (r = 0.384; p = 0.003). Similarly, protein and leucine consumption was positively correlated with muscle mass (r = 0.367 and 0.311, respectively; p = 0.005 for both). Conclusion: A low intake of calories, protein, and leucine is associated with reduced muscle mass in hip-fractured elderly. Given the relevance of sarcopenia as a risk factor for adverse outcomes in this patient population, our findings highlight the importance of a comprehensive dietary assessment for the detection of nutritional deficits predisposing to or aggravating muscle atrophy.
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Affiliation(s)
- Riccardo Calvani
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Anna Maria Martone
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Emanuele Marzetti
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Graziano Onder
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Giulia Savera
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Maria Lorenzi
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Elisabetta Serafini
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Roberto Bernabei
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
| | - Francesco Landi
- Department of Geriatrics, Neurosciences and Orthopedics, Teaching Hospital "Agostino Gemelli", Catholic University of the Sacred Heart School of Medicine , Rome , Italy
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737
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Abstract
Ultrasonography has previously been reported for use in the evaluation of compressive or traumatic peripheral nerve pathology and for its utility in preoperative mapping. However, these studies were not performed in infants, and they were not focused on the brachial plexus. The authors report a case in which ultrasonography was used to improve operative management of neonatal brachial plexus palsy (NBPP). An infant boy was born at term, complicated by right-sided shoulder dystocia. Initial clinical evaluation revealed proximal arm weakness consistent with an upper trunk injury. Unlike MRI or CT myelography that focus on proximal nerve roots, ultrasonography of the brachial plexus in the supraclavicular fossa was able to demonstrate a small neuroma involving the upper trunk (C-5 and C-6) and no asymmetry in movement of the diaphragm or in the appearance of the rhomboid muscle when compared with the unaffected side. However, the supra- and infraspinatus muscles were significantly asymmetrical and atrophied on the affected side. Importantly, ultrasound examination of the shoulder revealed posterior glenohumeral laxity. Instead of pursuing the primary nerve reconstruction first, timely treatment of the shoulder subluxation prevented formation of joint dysplasia and formation of a false glenoid, which is a common sequela of this condition. Because the muscles innervated by proximal branches of the cervical nerve roots/trunks were radiographically normal, subsequent nerve transfers were performed and good functional results were achieved. The authors believe this to be the first report describing the utility of ultrasonography in the surgical treatment planning in a case of NBPP. Noninvasive imaging, in addition to thorough history and physical examination, reduces the intraoperative time required to determine the extent and severity of nerve injury by allowing improved preoperative planning of the surgical strategy. Inclusion of ultrasonography as a preoperative modality may yield improved outcomes for children with NBPP.
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738
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Barker BL, McKenna S, Mistry V, Pancholi M, Patel H, Haldar K, Barer MR, Pavord ID, Steiner MC, Brightling CE, Bafadhel M. Systemic and pulmonary inflammation is independent of skeletal muscle changes in patients with chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2014; 9:975-81. [PMID: 25246784 PMCID: PMC4168852 DOI: 10.2147/copd.s63568] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Background Nutritional depletion is an important manifestation of chronic obstructive pulmonary disease (COPD), which has been related to systemic inflammation. It remains unclear to what degree airway inflammation contributes to the presence or progression of nutritional depletion. Objectives To determine whether airway inflammation and lung bacterial colonization are related to nutritional status or predict progressive weight loss and muscle atrophy in patients with COPD. Methods Body composition using dual energy X-ray absorptiometry, indices of airway inflammation, and bacterial colonization were measured in 234 COPD patients. Systemic inflammation was assessed from serum C reactive protein (CRP) and circulating total and differential leukocyte counts. Nutritional depletion was defined as a body mass index (BMI) less than 21 kg/m2 and/or fat-free mass index (FFMI) less than 15 or 17 kg/m2 in women and men, respectively. FFMI was calculated as the fat-free mass (FFM) corrected for body surface area. Measurements were repeated in 94 patients after a median 16-month follow-up. Regression analysis was used to assess the relationships of weight change and FFM change with indices of bacterial colonization and airway and systemic inflammation. Results Nutritional depletion occurred in 37% of patients. Lung function was worsened in patients with nutritional depletion compared to those without (forced expiratory volume in 1 second 1.17 L versus 1.41 L, mean difference 0.24, 95% confidence interval 0.10 to 0.38, P<0.01). There were no differences in airway inflammation and bacterial colonization in patients with and without nutritional depletion. At baseline, BMI correlated positively with serum CRP (rs=0.14, P=0.04). Change in weight and change in FFM over time could not be predicted from baseline patient characteristics. Conclusion Nutritional depletion and progressive muscle atrophy are not related to airway inflammation or bacterial colonization. Overspill of pulmonary inflammation is not a key driver of muscle atrophy in COPD.
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Affiliation(s)
- Bethan L Barker
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Susan McKenna
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Vijay Mistry
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Mitesh Pancholi
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Hemu Patel
- Department of Clinical Microbiology, University Hospitals of Leicester NHS Trust, Leicester, United Kingdom
| | - Koirobi Haldar
- Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Michael R Barer
- Department of Infection, Immunity, and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Ian D Pavord
- Respiratory Medicine Unit, Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
| | - Michael C Steiner
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Christopher E Brightling
- Institute for Lung Health, NIHR Respiratory Biomedical Research Unit, Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, United Kingdom
| | - Mona Bafadhel
- Respiratory Medicine Unit, Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
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739
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Abstract
Atrophy is a defining feature of aging skeletal muscle that contributes to progressive weakness and an increased risk of mobility impairment, falls, and physical frailty in very advanced age. Amongst the most frequently implicated mechanisms of aging muscle atrophy is mitochondrial dysfunction. Recent studies employing methods that are well-suited to interrogating intrinsic mitochondrial function find that mitochondrial respiration and reactive oxygen species emission changes are inconsistent between aging rat muscles undergoing atrophy and appear normal in human skeletal muscle from septuagenarian physically active subjects. On the other hand, a sensitization to permeability transition seems to be a general property of atrophying muscle with aging and this effect is even seen in atrophying muscle from physically active septuagenarian subjects. In addition to this intrinsic alteration in mitochondrial function, factors extrinsic to the mitochondria may also modulate mitochondrial function in aging muscle. In particular, recent evidence implicates oxidative stress in the aging milieu as a factor that depresses respiratory function in vivo (an effect that is not present ex vivo). Furthermore, in very advanced age, not only does muscle atrophy become more severe and clinically relevant in terms of its impact, but also there is evidence that this is driven by an accumulation of severely atrophied denervated myofibers. As denervation can itself modulate mitochondrial function and recruit mitochondrial-mediated atrophy pathways, future investigations need to address the degree to which skeletal muscle mitochondrial alterations in very advanced age are a consequence of denervation, rather than a primary organelle defect, to refine our understanding of the relevance of mitochondria as a therapeutic target at this more advanced age.
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Affiliation(s)
- Russell T Hepple
- Department of Kinesiology, McGill University Health Center, McGill University , Montreal, QC , Canada
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740
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Kern H, Barberi L, Löfler S, Sbardella S, Burggraf S, Fruhmann H, Carraro U, Mosole S, Sarabon N, Vogelauer M, Mayr W, Krenn M, Cvecka J, Romanello V, Pietrangelo L, Protasi F, Sandri M, Zampieri S, Musaro A. Electrical stimulation counteracts muscle decline in seniors. Front Aging Neurosci 2014; 6:189. [PMID: 25104935 PMCID: PMC4109438 DOI: 10.3389/fnagi.2014.00189] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 07/10/2014] [Indexed: 01/18/2023] Open
Abstract
The loss in muscle mass coupled with a decrease in specific force and shift in fiber composition are hallmarks of aging. Training and regular exercise attenuate the signs of sarcopenia. However, pathologic conditions limit the ability to perform physical exercise. We addressed whether electrical stimulation (ES) is an alternative intervention to improve muscle recovery and defined the molecular mechanism associated with improvement in muscle structure and function. We analyzed, at functional, structural, and molecular level, the effects of ES training on healthy seniors with normal life style, without routine sport activity. ES was able to improve muscle torque and functional performances of seniors and increased the size of fast muscle fibers. At molecular level, ES induced up-regulation of IGF-1 and modulation of MuRF-1, a muscle-specific atrophy-related gene. ES also induced up-regulation of relevant markers of differentiating satellite cells and of extracellular matrix remodeling, which might guarantee shape and mechanical forces of trained skeletal muscle as well as maintenance of satellite cell function, reducing fibrosis. Our data provide evidence that ES is a safe method to counteract muscle decline associated with aging.
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Affiliation(s)
- Helmut Kern
- Institute of Physical Medicine and Rehabilitation, Wilhelminenspital, Vienna, Austria
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Laura Barberi
- DAHFMO-Unit of Histology and Medical Embryology, Institute Pasteur Cenci-Bolognetti, IIM, Sapienza University of Rome, Rome, Italy
| | - Stefan Löfler
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Simona Sbardella
- DAHFMO-Unit of Histology and Medical Embryology, Institute Pasteur Cenci-Bolognetti, IIM, Sapienza University of Rome, Rome, Italy
| | - Samantha Burggraf
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Hannah Fruhmann
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
| | - Ugo Carraro
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
- Laboratory of Translation Myology, Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Simone Mosole
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
- Laboratory of Translation Myology, Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Nejc Sarabon
- Science and Research Centre, Institute for Kinesiology Research, University of Primorska, Koper, Slovenia
| | - Michael Vogelauer
- Institute of Physical Medicine and Rehabilitation, Wilhelminenspital, Vienna, Austria
| | - Winfried Mayr
- Center of Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Matthias Krenn
- Center of Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Jan Cvecka
- Faculty of Physical Education and Sport, Comenius University, Bratislava, Slovakia
| | - Vanina Romanello
- Dulbecco Telethon Institute at Venetian Institute of Molecular Medicine, Padova, Italy
| | - Laura Pietrangelo
- CeSI-Center for Research on Aging & DNICS – Department of Neuroscience, Imaging and Clinical Sciences, University G. d’Annunzio of Chieti, Chieti, Italy
| | - Feliciano Protasi
- CeSI-Center for Research on Aging & DNICS – Department of Neuroscience, Imaging and Clinical Sciences, University G. d’Annunzio of Chieti, Chieti, Italy
| | - Marco Sandri
- Dulbecco Telethon Institute at Venetian Institute of Molecular Medicine, Padova, Italy
| | - Sandra Zampieri
- Ludwig Boltzmann Institute of Electrical Stimulation and Physical Rehabilitation, Vienna, Austria
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Antonio Musaro
- DAHFMO-Unit of Histology and Medical Embryology, Institute Pasteur Cenci-Bolognetti, IIM, Sapienza University of Rome, Rome, Italy
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
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741
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Sanchis-Gomar F, Pareja-Galeano H, Mayero S, Perez-Quilis C, Lucia A. New molecular targets and lifestyle interventions to delay aging sarcopenia. Front Aging Neurosci 2014; 6:156. [PMID: 25071565 PMCID: PMC4078253 DOI: 10.3389/fnagi.2014.00156] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 06/18/2014] [Indexed: 12/25/2022] Open
Affiliation(s)
- Fabian Sanchis-Gomar
- Department of Physiology, Faculty of Medicine, University of Valencia and Fundación Investigación Hospital Clínico Universitario INCLIVA , Valencia , Spain ; Department of Molecular and Mitochondrial Medicine, University Research Institute "Dr. Viña Giner", Catholic University of Valencia "San Vicente Mártir" , Valencia , Spain
| | - Helios Pareja-Galeano
- Department of Physiology, Faculty of Medicine, University of Valencia and Fundación Investigación Hospital Clínico Universitario INCLIVA , Valencia , Spain
| | - Sara Mayero
- Department of Psychiatry, Hospital General Universitario , Valencia , Spain
| | - Carme Perez-Quilis
- Department of Molecular and Mitochondrial Medicine, University Research Institute "Dr. Viña Giner", Catholic University of Valencia "San Vicente Mártir" , Valencia , Spain
| | - Alejandro Lucia
- Universidad Europea and Research Institute of Hospital 12 de Octubre (i+12) , Madrid , Spain
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742
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Troncoso R, Paredes F, Parra V, Gatica D, Vásquez-Trincado C, Quiroga C, Bravo-Sagua R, López-Crisosto C, Rodriguez AE, Oyarzún AP, Kroemer G, Lavandero S. Dexamethasone-induced autophagy mediates muscle atrophy through mitochondrial clearance. Cell Cycle 2014; 13:2281-95. [PMID: 24897381 DOI: 10.4161/cc.29272] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoids, such as dexamethasone, enhance protein breakdown via ubiquitin-proteasome system. However, the role of autophagy in organelle and protein turnover in the glucocorticoid-dependent atrophy program remains unknown. Here, we show that dexamethasone stimulates an early activation of autophagy in L6 myotubes depending on protein kinase, AMPK, and glucocorticoid receptor activity. Dexamethasone increases expression of several autophagy genes, including ATG5, LC3, BECN1, and SQSTM1 and triggers AMPK-dependent mitochondrial fragmentation associated with increased DNM1L protein levels. This process is required for mitophagy induced by dexamethasone. Inhibition of mitochondrial fragmentation by Mdivi-1 results in disrupted dexamethasone-induced autophagy/mitophagy. Furthermore, Mdivi-1 increases the expression of genes associated with the atrophy program, suggesting that mitophagy may serve as part of the quality control process in dexamethasone-treated L6 myotubes. Collectively, these data suggest a novel role for dexamethasone-induced autophagy/mitophagy in the regulation of the muscle atrophy program.
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Affiliation(s)
- Rodrigo Troncoso
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Felipe Paredes
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Valentina Parra
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile; Department of Internal Medicine (Cardiology Division); University of Texas Southwestern Medical Center; Dallas, TX USA
| | - Damián Gatica
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - César Vásquez-Trincado
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Clara Quiroga
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Roberto Bravo-Sagua
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Camila López-Crisosto
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Andrea E Rodriguez
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Alejandra P Oyarzún
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile
| | - Guido Kroemer
- Equipe 11 labellisée pas la Ligue Nationale contre le Cancer; INSERM; Centre de Recherche des Cordeliers; Paris, France; Metabolomics and Cell Biology Platforms; Institut Gustave Roussy; Villejuif, France; Pôle de Biologie; Hôpital Européen Georges Pompidou; AP-HP; Paris, France; Université Paris Descartes; Paris Sorbonne Cité; Paris, France
| | - Sergio Lavandero
- Advanced Center for Chronic Disease (ACCDiS); University of Chile; Santiago, Chile; Center for Molecular Studies of the Cell; Faculty of Chemical & Pharmaceutical Sciences & Faculty of Medicine; University of Chile; Santiago, Chile; Department of Internal Medicine (Cardiology Division); University of Texas Southwestern Medical Center; Dallas, TX USA
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743
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de Campos-Ferraz PL, Andrade I, das Neves W, Hangai I, Alves CRR, Lancha AH. An overview of amines as nutritional supplements to counteract cancer cachexia. J Cachexia Sarcopenia Muscle 2014; 5:105-10. [PMID: 24676930 PMCID: PMC4053561 DOI: 10.1007/s13539-014-0138-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 02/17/2014] [Indexed: 01/06/2023] Open
Abstract
Cancer cachexia is a complex multifactorial syndrome characterized by loss of skeletal muscle mass (with or without loss of fat mass) that cannot be fully reversed by conventional nutritional support and leads to progressive functional impairment. Recently, some amino acids and other amine dietary supplements have been highlighted in medical field due to positive effects upon diseases evolving skeletal muscle atrophy. Therefore, the aim of this brief review is to discuss the putative application of amines as dietary supplements to counteract skeletal muscle wasting on cancer cachexia. Specifically, we focus in two nutritional supplements: (1) branched-chain amino acids (BCAAs) and (2) creatine. Both BCAAs and creatine may attenuate proteolysis and enhance proteins synthesis in skeletal muscle. Although more experimental studies and clinical trials are still necessary to elucidate this therapeutic application, several evidences have demonstrated that amines supplementation is a promising coadjuvant treatment to cancer cachexia.
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Affiliation(s)
- Patrícia Lopes de Campos-Ferraz
- University of São Paulo, School of Physical Education and Sport, Av. Prof. Mello Moraes, 65-05508-030, São Paulo, SP, Brazil,
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744
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Zhang BT, Yeung SS, Cheung KK, Chai ZY, Yeung EW. Adaptive responses of TRPC1 and TRPC3 during skeletal muscle atrophy and regrowth. Muscle Nerve 2014; 49:691-9. [PMID: 23852583 DOI: 10.1002/mus.23952] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 07/04/2013] [Accepted: 07/06/2013] [Indexed: 12/20/2022]
Abstract
INTRODUCTION We assessed the time-dependent changes of transient receptor potential canonical type 1 (TRPC1) and TRPC3 expression and localization associated with muscle atrophy and regrowth in vivo. METHODS Mice were subjected to hindlimb unloading for 7 or 14 days (7U, 14U) followed by 3, 7, or 14 days of reloading (3R, 7R, 14R). RESULTS Soleus muscle mass and tetanic force were reduced significantly at 7U and 14U and recovered by 14R. Recovery of muscle fiber cross-sectional area was observed by 28R. TRPC1 mRNA was unaltered during the unloading-reloading period. However, protein expression remained depressed through 14R. Decreased localization of TRPC1 to the sarcolemma was observed. TRPC3 mRNA and protein expression levels were decreased significantly during the early phase of reloading. CONCLUSIONS Given the known role of these channels in muscle development, changes observed in TRPC1 and TRPC3 may relate closely to muscle atrophy and remodeling processes.
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Affiliation(s)
- Bao-Ting Zhang
- Muscle Physiology Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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745
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Demos-Davies KM, Ferguson BS, Cavasin MA, Mahaffey JH, Williams SM, Spiltoir JI, Schuetze KB, Horn TR, Chen B, Ferrara C, Scellini B, Piroddi N, Tesi C, Poggesi C, Jeong MY, McKinsey TA. HDAC6 contributes to pathological responses of heart and skeletal muscle to chronic angiotensin-II signaling. Am J Physiol Heart Circ Physiol 2014; 307:H252-8. [PMID: 24858848 DOI: 10.1152/ajpheart.00149.2014] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Little is known about the function of the cytoplasmic histone deacetylase HDAC6 in striated muscle. Here, we addressed the role of HDAC6 in cardiac and skeletal muscle remodeling induced by the peptide hormone angiotensin II (ANG II), which plays a central role in blood pressure control, heart failure, and associated skeletal muscle wasting. Comparable with wild-type (WT) mice, HDAC6 null mice developed cardiac hypertrophy and fibrosis in response to ANG II. However, whereas WT mice developed systolic dysfunction upon treatment with ANG II, cardiac function was maintained in HDAC6 null mice treated with ANG II for up to 8 wk. The cardioprotective effect of HDAC6 deletion was mimicked in WT mice treated with the small molecule HDAC6 inhibitor tubastatin A. HDAC6 null mice also exhibited improved left ventricular function in the setting of pressure overload mediated by transverse aortic constriction. HDAC6 inhibition appeared to preserve systolic function, in part, by enhancing cooperativity of myofibrillar force generation. Finally, we show that HDAC6 null mice are resistant to skeletal muscle wasting mediated by chronic ANG-II signaling. These findings define novel roles for HDAC6 in striated muscle and suggest potential for HDAC6-selective inhibitors for the treatment of cardiac dysfunction and muscle wasting in patients with heart failure.
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Affiliation(s)
- Kimberly M Demos-Davies
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Bradley S Ferguson
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Maria A Cavasin
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Jennifer H Mahaffey
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Sarah M Williams
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Jessica I Spiltoir
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Katherine B Schuetze
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Todd R Horn
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Bo Chen
- Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut; and
| | - Claudia Ferrara
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Beatrice Scellini
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Nicoletta Piroddi
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Chiara Tesi
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Corrado Poggesi
- Dipartimento di Medicina Sperimentale e Clinica, Università degli Studi di Firenze, Firenze, Italy
| | - Mark Y Jeong
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado
| | - Timothy A McKinsey
- Division of Cardiology, Department of Medicine, University of Colorado Denver, Aurora, Colorado;
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746
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Fanin M, Nascimbeni AC, Angelini C. Muscle atrophy, ubiquitin-proteasome, and autophagic pathways in dysferlinopathy. Muscle Nerve 2014; 50:340-7. [PMID: 24395438 DOI: 10.1002/mus.24167] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 12/18/2013] [Accepted: 01/02/2014] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Muscle fiber atrophy and the molecular pathways underlying this process have not been investigated in dysferlinopathy patients. METHODS In 22 muscles from dysferlinopathy patients we investigated fiber atrophy by morphometry and ubiquitin-proteasome and autophagic pathways using protein and/or transcriptional analysis of atrophy- and autophagy-related genes (MuRF1, atrogin1, LC3, p62, Bnip3). RESULTS Dysferlinopathy showed significant fiber atrophy and higher MuRF-1 protein and mRNA levels, which correlated with fiber size, suggesting activation of the atrophy program by proteasome induction. CONCLUSIONS Some of the MuRF-1 upregulation and proteasome induction may be attributed to the prominent regeneration found. A potential role of impaired autophagy was suggested by p62-positive protein aggregates in atrophic fibers and significantly higher levels of LC3-II and p62 proteins and overexpression of p62 and Bnip3 mRNA. Damaged muscle fibers and prominent inflammatory changes may also enhance autophagy due to the insufficient level of proteasomal degradation of mutant dysferlin.
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Affiliation(s)
- Marina Fanin
- Department of Neurosciences, University of Padova, Biomedical Campus "Pietro d'Abano," via Giuseppe Orus 2B, 35129, Padova, Italy
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747
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Doig J, Griffiths LA, Peberdy D, Dharmasaroja P, Vera M, Davies FJC, Newbery HJ, Brownstein D, Abbott CM. In vivo characterization of the role of tissue-specific translation elongation factor 1A2 in protein synthesis reveals insights into muscle atrophy. FEBS J 2014; 280:6528-40. [PMID: 24460877 PMCID: PMC4163635 DOI: 10.1111/febs.12554] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Translation elongation factor 1A2 (eEF1A2), uniquely among translation factors, is expressed specifically in neurons and muscle. eEF1A2‐null mutant wasted mice develop an aggressive, early‐onset form of neurodegeneration, but it is unknown whether the wasting results from denervation of the muscles, or whether the mice have a primary myopathy resulting from loss of translation activity in muscle. We set out to establish the relative contributions of loss of eEF1A2 in the different tissues to this postnatal lethal phenotype. We used tissue‐specific transgenesis to show that correction of eEF1A2 levels in muscle fails to ameliorate the overt phenotypic abnormalities or time of death of wasted mice. Molecular markers of muscle atrophy such as Fbxo32 were dramatically upregulated at the RNA level in wasted mice, both in the presence and in the absence of muscle‐specific expression of eEF1A2, but the degree of upregulation at the protein level was significantly lower in those wasted mice without transgene‐derived expression of eEF1A2 in muscle. This provides the first in vivo confirmation that eEF1A2 plays an important role in translation. In spite of the inability of the nontransgenic wasted mice to upregulate key atrogenes at the protein level in response to denervation to the same degree as their transgenic counterparts, there were no measurable differences between transgenic and nontransgenic wasted mice in terms of weight loss, grip strength, or muscle pathology. This suggests that a compromised ability fully to execute the atrogene pathway in denervated muscle does not affect the process of muscle atrophy in the short term.
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Affiliation(s)
- Jennifer Doig
- Medical Genetics Section, Molecular Medicine Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, UK
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748
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Uezumi A, Ikemoto-Uezumi M, Tsuchida K. Roles of nonmyogenic mesenchymal progenitors in pathogenesis and regeneration of skeletal muscle. Front Physiol 2014; 5:68. [PMID: 24605102 PMCID: PMC3932482 DOI: 10.3389/fphys.2014.00068] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Accepted: 02/04/2014] [Indexed: 12/25/2022] Open
Abstract
Adult skeletal muscle possesses a remarkable regenerative ability that is dependent on satellite cells. However, skeletal muscle is replaced by fatty and fibrous connective tissue in several pathological conditions. Fatty and fibrous connective tissue becomes a major cause of muscle weakness and leads to further impairment of muscle function. Because the occurrence of fatty and fibrous connective tissue is usually associated with severe destruction of muscle, the idea that dysregulation of the fate switch in satellite cells may underlie this pathological change has emerged. However, recent studies identified nonmyogenic mesenchymal progenitors in skeletal muscle and revealed that fatty and fibrous connective tissue originates from these progenitors. Later, these progenitors were also demonstrated to be the major contributor to heterotopic ossification in skeletal muscle. Because nonmyogenic mesenchymal progenitors represent a distinct cell population from satellite cells, targeting these progenitors could be an ideal therapeutic strategy that specifically prevents pathological changes of skeletal muscle, while preserving satellite cell-dependent regeneration. In addition to their roles in pathogenesis of skeletal muscle, nonmyogenic mesenchymal progenitors may play a vital role in muscle regeneration by regulating satellite cell behavior. Conversely, muscle cells appear to regulate behavior of nonmyogenic mesenchymal progenitors. Thus, these cells regulate each other reciprocally and a proper balance between them is a key determinant of muscle integrity. Furthermore, nonmyogenic mesenchymal progenitors have been shown to maintain muscle mass in a steady homeostatic condition. Understanding the nature of nonmyogenic mesenchymal progenitors will provide valuable insight into the pathophysiology of skeletal muscle. In this review, we focus on nonmyogenic mesenchymal progenitors and discuss their roles in muscle pathogenesis, regeneration, and homeostasis.
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Affiliation(s)
- Akiyoshi Uezumi
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University Aichi, Japan
| | - Madoka Ikemoto-Uezumi
- Department of Regenerative Medicine, National Center for Geriatrics and Gerontology, National Institute for Longevity Sciences Aichi, Japan
| | - Kunihiro Tsuchida
- Division for Therapies against Intractable Diseases, Institute for Comprehensive Medical Science, Fujita Health University Aichi, Japan
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Abstract
Topical Bimatoprost is a common and popular prostaglandin analog used as an ocular hypotensive agent in the treatment of glaucoma. Side effects include ocular hyperaemia, ocular pruritus, and periocular and iris pigmentary changes. Perioribital lipodystrophy is another well-documented outcome associated with chronic use of topical bimatoprost, which results in periorbital hallowing, upper eyelid sulcus deepening, eyelid retraction and enophthalmos. We report an unusual case of periocular muscle atrophy and weakness from unilateral topical bimatoprost use. Our patient had primary angle closure and experienced a right upper eyelid ptosis 2 months after she started to use topical bimatoprost in that eye. Clinical measurements of her eyelids clearly showed reduction in the function of her right levator muscle, suggesting that effects of topical bimatoprost may not be limited to periorbital fat. She was advised to stop topical bimatoprost and right ptosis correction surgery with levator muscle advancement was performed successfully. Ophthalmologists and patients should be aware of this potential rare side effect of topical bimatoprost, as it may be potentially disfiguring, especially with monocular use. However, its exact mechanism of action needs to be clarified further.
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Affiliation(s)
| | | | - Jin Fong Cheng
- Department of Ophthalmology, National University Health System, Singapore
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750
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Piccirillo R, Demontis F, Perrimon N, Goldberg AL. Mechanisms of muscle growth and atrophy in mammals and Drosophila. Dev Dyn 2014; 243:201-15. [PMID: 24038488 PMCID: PMC3980484 DOI: 10.1002/dvdy.24036] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 08/01/2013] [Accepted: 08/01/2013] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The loss of skeletal muscle mass (atrophy) that accompanies disuse and systemic diseases is highly debilitating. Although the pathogenesis of this condition has been primarily studied in mammals, Drosophila is emerging as an attractive system to investigate some of the mechanisms involved in muscle growth and atrophy. RESULTS In this review, we highlight the outstanding unsolved questions that may benefit from a combination of studies in both flies and mammals. In particular, we discuss how different environmental stimuli and signaling pathways influence muscle mass and strength and how a variety of disease states can cause muscle wasting. CONCLUSIONS Studies in Drosophila and mammals should help identify molecular targets for the treatment of muscle wasting in humans.
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Affiliation(s)
- Rosanna Piccirillo
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115
- Department of Oncology, IRCCS - Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Fabio Demontis
- Department of Genetics, Harvard Medical School, Boston, MA 02115
- Department of Developmental Neurobiology, Division of Developmental Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Boston, MA 02115
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115
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