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Xie MX, Rao JH, Tian XY, Liu JK, Li X, Chen ZY, Cao Y, Chen AN, Shu HH, Zhang XL. ATF4 inhibits TRPV4 function and controls itch perception in rodents and nonhuman primates. Pain 2024; 165:1840-1859. [PMID: 38422489 DOI: 10.1097/j.pain.0000000000003189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 01/03/2024] [Indexed: 03/02/2024]
Abstract
ABSTRACT Acute and chronic itch are prevalent and incapacitating, yet the neural mechanisms underlying both acute and chronic itch are just starting to be unraveled. Activated transcription factor 4 (ATF4) belongs to the ATF/CREB transcription factor family and primarily participates in the regulation of gene transcription. Our previous study has demonstrated that ATF4 is expressed in sensory neurons. Nevertheless, the role of ATF4 in itch sensation remains poorly understood. Here, we demonstrate that ATF4 plays a significant role in regulating itch sensation. The absence of ATF4 in dorsal root ganglion (DRG) neurons enhances the itch sensitivity of mice. Overexpression of ATF4 in sensory neurons significantly alleviates the acute and chronic pruritus in mice. Furthermore, ATF4 interacts with the transient receptor potential cation channel subfamily V member 4 (TRPV4) and inhibits its function without altering the expression or membrane trafficking of TRPV4 in sensory neurons. In addition, interference with ATF4 increases the itch sensitivity in nonhuman primates and enhances TRPV4 currents in nonhuman primates DRG neurons; ATF4 and TRPV4 also co-expresses in human sensory neurons. Our data demonstrate that ATF4 controls pruritus by regulating TRPV4 signaling through a nontranscriptional mechanism and identifies a potential new strategy for the treatment of pathological pruritus.
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Affiliation(s)
- Man-Xiu Xie
- Department of Anesthesiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Guangzhou, China
| | - Jun-Hua Rao
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Xiao-Yu Tian
- Medical Research Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Jin-Kun Liu
- Medical Research Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Guangzhou, China
| | - Xiao Li
- College of Food Science and Technology, Hainan University, Haikou, China
| | - Zi-Yi Chen
- Zhongshan School of Medicine of Sun Yat-sen University, Guangzhou, China
| | - Yan Cao
- College of Food Science and Technology, Hainan University, Haikou, China
| | - An-Nan Chen
- Zhongshan School of Medicine of Sun Yat-sen University, Guangzhou, China
| | - Hai-Hua Shu
- Department of Anesthesiology, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Xiao-Long Zhang
- Medical Research Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
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2
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Wischnewski S, Thäwel T, Ikenaga C, Kocharyan A, Lerma-Martin C, Zulji A, Rausch HW, Brenner D, Thomas L, Kutza M, Wick B, Trobisch T, Preusse C, Haeussler M, Leipe J, Ludolph A, Rosenbohm A, Hoke A, Platten M, Weishaupt JH, Sommer CJ, Stenzel W, Lloyd TE, Schirmer L. Cell type mapping of inflammatory muscle diseases highlights selective myofiber vulnerability in inclusion body myositis. NATURE AGING 2024; 4:969-983. [PMID: 38834884 PMCID: PMC11257986 DOI: 10.1038/s43587-024-00645-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 05/03/2024] [Indexed: 06/06/2024]
Abstract
Inclusion body myositis (IBM) is the most prevalent inflammatory muscle disease in older adults with no effective therapy available. In contrast to other inflammatory myopathies such as subacute, immune-mediated necrotizing myopathy (IMNM), IBM follows a chronic disease course with both inflammatory and degenerative features of pathology. Moreover, causal factors and molecular drivers of IBM progression are largely unknown. Therefore, we paired single-nucleus RNA sequencing with spatial transcriptomics from patient muscle biopsies to map cell-type-specific drivers underlying IBM pathogenesis compared with IMNM muscles and noninflammatory skeletal muscle samples. In IBM muscles, we observed a selective loss of type 2 myonuclei paralleled by increased levels of cytotoxic T and conventional type 1 dendritic cells. IBM myofibers were characterized by either upregulation of cell stress markers featuring GADD45A and NORAD or protein degradation markers including RNF7 associated with p62 aggregates. GADD45A upregulation was preferentially seen in type 2A myofibers associated with severe tissue inflammation. We also noted IBM-specific upregulation of ACHE encoding acetylcholinesterase, which can be regulated by NORAD activity and result in functional denervation of myofibers. Our results provide promising insights into possible mechanisms of myofiber degeneration in IBM and suggest a selective type 2 fiber vulnerability linked to genomic stress and denervation pathways.
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Grants
- R01 AR076390 NIAMS NIH HHS
- U41 HG002371 NHGRI NIH HHS
- European Research Council (DecOmPress ERC StG 950584), German Research Foundation grant (SCHI 1330/2-1, SCHI 1330/4-1, SCHI 1330/6-1, GRK 2727, SPP 2395), Hertie Foundation (P1180016), National Multiple Sclerosis Society (RFA-2203-39300, PA-2002-36405)
- The Myositis Association (90097118)
- German Cancer Aid
- National Human Genome Research Institute (5U41HG002371)
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01-AR076390), Muscular Dystrophy Association (MDA630399), The Peter and Carmen Lucia Buck Foundation, The Peter Frampton Myositis Research Fund
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Affiliation(s)
- Sven Wischnewski
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Thomas Thäwel
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Chiseko Ikenaga
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Anna Kocharyan
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Celia Lerma-Martin
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Amel Zulji
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Hans-Werner Rausch
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - David Brenner
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Neurology, University of Ulm, Ulm, Germany
| | - Leonie Thomas
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Michael Kutza
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Brittney Wick
- Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Tim Trobisch
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Corinna Preusse
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | | | - Jan Leipe
- Division of Rheumatology, Department of Medicine V, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Albert Ludolph
- Department of Neurology, University of Ulm, Ulm, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen, Ulm, Germany
| | | | - Ahmet Hoke
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael Platten
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- DKTK Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center, Heidelberg, Germany
- Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Mannheim Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Interdisciplinary Center for Neurosciences, Heidelberg University, Heidelberg, Germany
| | - Jochen H Weishaupt
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Mannheim Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Interdisciplinary Center for Neurosciences, Heidelberg University, Heidelberg, Germany
| | - Clemens J Sommer
- Institute for Neuropathology, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Werner Stenzel
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Thomas E Lloyd
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Baylor College of Medicine, Houston, TX, USA.
| | - Lucas Schirmer
- Department of Neurology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
- Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
- Mannheim Institute for Innate Immunoscience, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
- Interdisciplinary Center for Neurosciences, Heidelberg University, Heidelberg, Germany.
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3
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Igami K, Kittaka H, Yagi M, Gotoh K, Matsushima Y, Ide T, Ikeda M, Ueda S, Nitta SI, Hayakawa M, Nakayama KI, Matsumoto M, Kang D, Uchiumi T. iMPAQT reveals that adequate mitohormesis from TFAM overexpression leads to life extension in mice. Life Sci Alliance 2024; 7:e202302498. [PMID: 38664021 PMCID: PMC11046090 DOI: 10.26508/lsa.202302498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 04/13/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Mitochondrial transcription factor A, TFAM, is essential for mitochondrial function. We examined the effects of overexpressing the TFAM gene in mice. Two types of transgenic mice were created: TFAM heterozygous (TFAM Tg) and homozygous (TFAM Tg/Tg) mice. TFAM Tg/Tg mice were smaller and leaner notably with longer lifespans. In skeletal muscle, TFAM overexpression changed gene and protein expression in mitochondrial respiratory chain complexes, with down-regulation in complexes 1, 3, and 4 and up-regulation in complexes 2 and 5. The iMPAQT analysis combined with metabolomics was able to clearly separate the metabolomic features of the three types of mice, with increased degradation of fatty acids and branched-chain amino acids and decreased glycolysis in homozygotes. Consistent with these observations, comprehensive gene expression analysis revealed signs of mitochondrial stress, with elevation of genes associated with the integrated and mitochondrial stress responses, including Atf4, Fgf21, and Gdf15. These found that mitohormesis develops and metabolic shifts in skeletal muscle occur as an adaptive strategy.
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Affiliation(s)
- Ko Igami
- LSI Medience Corporation, Tokyo, Japan
- Kyushu Pro Search Limited Liability Partnership, Fukuoka, Japan
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Hiroki Kittaka
- LSI Medience Corporation, Tokyo, Japan
- Kyushu Pro Search Limited Liability Partnership, Fukuoka, Japan
| | - Mikako Yagi
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
- https://ror.org/00p4k0j84 Clinical Chemistry, Division of Biochemical Science and Technology, Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Kazuhito Gotoh
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
- Department of Laboratory Medicine, Tokai University School of Medicine, Kanagawa, Japan
| | - Yuichi Matsushima
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
- https://ror.org/035t8zc32 Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Japan
| | - Tomomi Ide
- https://ror.org/00p4k0j84 Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masataka Ikeda
- https://ror.org/00p4k0j84 Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Saori Ueda
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Shin-Ichiro Nitta
- LSI Medience Corporation, Tokyo, Japan
- Kyushu Pro Search Limited Liability Partnership, Fukuoka, Japan
| | - Manami Hayakawa
- Kyushu Pro Search Limited Liability Partnership, Fukuoka, Japan
| | - Keiichi I Nakayama
- https://ror.org/00p4k0j84 Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
- Anticancer Strategies Laboratory, TMDU Advanced Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masaki Matsumoto
- Department of Omics and Systems Biology, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Dongchon Kang
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
- Kashiigaoka Rehabilitation Hospital, Fukuoka, Japan
| | - Takeshi Uchiumi
- https://ror.org/00p4k0j84 Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
- https://ror.org/00p4k0j84 Clinical Chemistry, Division of Biochemical Science and Technology, Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
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4
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Vanhoutte D, Schips TG, Minerath RA, Huo J, Kavuri NSS, Prasad V, Lin SC, Bround MJ, Sargent MA, Adams CM, Molkentin JD. Thbs1 regulates skeletal muscle mass in a TGFβ-Smad2/3-ATF4-dependent manner. Cell Rep 2024; 43:114149. [PMID: 38678560 PMCID: PMC11217783 DOI: 10.1016/j.celrep.2024.114149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 03/22/2024] [Accepted: 04/09/2024] [Indexed: 05/01/2024] Open
Abstract
Loss of muscle mass is a feature of chronic illness and aging. Here, we report that skeletal muscle-specific thrombospondin-1 transgenic mice (Thbs1 Tg) have profound muscle atrophy with age-dependent decreases in exercise capacity and premature lethality. Mechanistically, Thbs1 activates transforming growth factor β (TGFβ)-Smad2/3 signaling, which also induces activating transcription factor 4 (ATF4) expression that together modulates the autophagy-lysosomal pathway (ALP) and ubiquitin-proteasome system (UPS) to facilitate muscle atrophy. Indeed, myofiber-specific inhibition of TGFβ-receptor signaling represses the induction of ATF4, normalizes ALP and UPS, and partially restores muscle mass in Thbs1 Tg mice. Similarly, myofiber-specific deletion of Smad2 and Smad3 or the Atf4 gene antagonizes Thbs1-induced muscle atrophy. More importantly, Thbs1-/- mice show significantly reduced levels of denervation- and caloric restriction-mediated muscle atrophy, along with blunted TGFβ-Smad3-ATF4 signaling. Thus, Thbs1-mediated TGFβ-Smad3-ATF4 signaling in skeletal muscle regulates tissue rarefaction, suggesting a target for atrophy-based muscle diseases and sarcopenia with aging.
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Affiliation(s)
- Davy Vanhoutte
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Tobias G Schips
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Rachel A Minerath
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Jiuzhou Huo
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Naga Swathi Sree Kavuri
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Vikram Prasad
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Suh-Chin Lin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Michael J Bround
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Michelle A Sargent
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Christopher M Adams
- Division of Endocrinology, Metabolism and Nutrition, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Jeffery D Molkentin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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5
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Cefis M, Dargegen M, Marcangeli V, Taherkhani S, Dulac M, Leduc-Gaudet JP, Mayaki D, Hussain SNA, Gouspillou G. MFN2 overexpression in skeletal muscles of young and old mice causes a mild hypertrophy without altering mitochondrial respiration and H 2O 2 emission. Acta Physiol (Oxf) 2024; 240:e14119. [PMID: 38400630 DOI: 10.1111/apha.14119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 02/06/2024] [Accepted: 02/11/2024] [Indexed: 02/25/2024]
Abstract
AIM Sarcopenia, the aging-related loss of muscle mass and function, is a debilitating process negatively impacting the quality of life of affected individuals. Although the mechanisms underlying sarcopenia are incompletely understood, impairments in mitochondrial dynamics, including mitochondrial fusion, have been proposed as a contributing factor. However, the potential of upregulating mitochondrial fusion proteins to alleviate the effects of aging on skeletal muscles remains unexplored. We therefore hypothesized that overexpressing Mitofusin 2 (MFN2) in skeletal muscle in vivo would mitigate the effects of aging on muscle mass and improve mitochondrial function. METHODS MFN2 was overexpressed in young (7 mo) and old (24 mo) male mice for 4 months through intramuscular injections of an adeno-associated viruses. The impacts of MFN2 overexpression on muscle mass and fiber size (histology), mitochondrial respiration, and H2O2 emission (Oroboros fluororespirometry), and various signaling pathways (qPCR and western blotting) were investigated. RESULTS MFN2 overexpression increased muscle mass and fiber size in both young and old mice. No sign of fibrosis, necrosis, or inflammation was found upon MFN2 overexpression, indicating that the hypertrophy triggered by MFN2 overexpression was not pathological. MFN2 overexpression even reduced the proportion of fibers with central nuclei in old muscles. Importantly, MFN2 overexpression had no impact on muscle mitochondrial respiration and H2O2 emission in both young and old mice. MFN2 overexpression attenuated the increase in markers of impaired autophagy in old muscles. CONCLUSION MFN2 overexpression may be a viable approach to mitigate aging-related muscle atrophy and may have applications for other muscle disorders.
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Affiliation(s)
- Marina Cefis
- Département des sciences de l'activité physique, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
| | - Manon Dargegen
- Département des sciences de l'activité physique, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
| | - Vincent Marcangeli
- Département des sciences de l'activité physique, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
- Département des sciences biologiques, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
| | - Shima Taherkhani
- Département des sciences de l'activité physique, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
- Département des sciences biologiques, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
| | - Maude Dulac
- Division of Experimental Medicine, Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Jean-Philippe Leduc-Gaudet
- Research Group in Cellular Signaling, Department of Medical Biology, Université du Québec À Trois-Rivières, Trois-Rivières, Québec, Canada
| | - Dominique Mayaki
- Division of Experimental Medicine, Department of Medicine, McGill University, Montréal, Québec, Canada
- Meakins-Christie Laboratories and Translational Research in Respiratory Diseases Program, Department of Critical Care, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Sabah N A Hussain
- Division of Experimental Medicine, Department of Medicine, McGill University, Montréal, Québec, Canada
- Meakins-Christie Laboratories and Translational Research in Respiratory Diseases Program, Department of Critical Care, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Gilles Gouspillou
- Département des sciences de l'activité physique, Faculté des Sciences, UQÀM, Montréal, Québec, Canada
- Meakins-Christie Laboratories and Translational Research in Respiratory Diseases Program, Department of Critical Care, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
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6
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Zhong S, Zhang Y, Mou H, Jian C, Huang Q, Ou Y. Targeting PERK-ATF4-P21 axis enhances the sensitivity of osteosarcoma HOS cells to Mppα-PDT. Aging (Albany NY) 2024; 16:2789-2811. [PMID: 38319715 PMCID: PMC10911341 DOI: 10.18632/aging.205511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/29/2023] [Indexed: 02/07/2024]
Abstract
Osteosarcoma (OS) is the most prevalent type of malignant bone tumor in adolescents. The overall survival of OS patients has reached a plateau recently. Thus, there is an urgent need to develop approaches to improve the sensitivity of OS to therapies. Pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPα-PDT) is a new type of tumor therapy, and elucidating its mechanism is helpful to improve its anti-tumor efficacy. Here, we investigated how PERK signaling promotes the human OS (HOS) cell survival induced by MPPα-PDT, as overcoming this may enhance sensitivity to MPPα-PDT. We found that MPPα-PDT combined with PERK inhibitor GSK2656157 enhanced HOS cell apoptosis by suppressing autophagy and p21. Autophagy inhibition and p21 depletion enhanced cell death, indicating pro-survival effects in MPPα-PDT. Notably, p21 was found to be an effector of the PERK-Atf4 pathway, which could positively regulate autophagy mediated by MPPα-PDT. In conclusion, we found that the combination of MPPα-PDT and GSK2656157 enhanced apoptosis in HOS cells by inhibiting autophagy. Mechanistically, this autophagy is p21-dependent and can be suppressed by GSK2656157, thereby enhancing sensitivity to MPPα-PDT.
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Affiliation(s)
- Shenxi Zhong
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
| | - Ye Zhang
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
| | - Hai Mou
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
| | - Changchun Jian
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
| | - Qiu Huang
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
| | - Yunsheng Ou
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing 400016, China
- Orthopedic Laboratory of Chongqing Medical University, Yuzhong, Chongqing 400016, China
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7
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Di Marco G, Gherardi G, De Mario A, Piazza I, Baraldo M, Mattarei A, Blaauw B, Rizzuto R, De Stefani D, Mammucari C. The mitochondrial ATP-dependent potassium channel (mitoK ATP) controls skeletal muscle structure and function. Cell Death Dis 2024; 15:58. [PMID: 38233399 PMCID: PMC10794173 DOI: 10.1038/s41419-024-06426-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 12/20/2023] [Accepted: 01/02/2024] [Indexed: 01/19/2024]
Abstract
MitoKATP is a channel of the inner mitochondrial membrane that controls mitochondrial K+ influx according to ATP availability. Recently, the genes encoding the pore-forming (MITOK) and the regulatory ATP-sensitive (MITOSUR) subunits of mitoKATP were identified, allowing the genetic manipulation of the channel. Here, we analyzed the role of mitoKATP in determining skeletal muscle structure and activity. Mitok-/- muscles were characterized by mitochondrial cristae remodeling and defective oxidative metabolism, with consequent impairment of exercise performance and altered response to damaging muscle contractions. On the other hand, constitutive mitochondrial K+ influx by MITOK overexpression in the skeletal muscle triggered overt mitochondrial dysfunction and energy default, increased protein polyubiquitination, aberrant autophagy flux, and induction of a stress response program. MITOK overexpressing muscles were therefore severely atrophic. Thus, the proper modulation of mitoKATP activity is required for the maintenance of skeletal muscle homeostasis and function.
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Affiliation(s)
- Giulia Di Marco
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Gaia Gherardi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Agnese De Mario
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Ilaria Piazza
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | | | - Andrea Mattarei
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Bert Blaauw
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Venetian Institute of Molecular Medicine, Padova, Italy
- Myology Center (CIR-Myo), University of Padova, Padova, Italy
| | - Rosario Rizzuto
- Department of Biomedical Sciences, University of Padova, Padova, Italy
- Myology Center (CIR-Myo), University of Padova, Padova, Italy
| | - Diego De Stefani
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Cristina Mammucari
- Department of Biomedical Sciences, University of Padova, Padova, Italy.
- Myology Center (CIR-Myo), University of Padova, Padova, Italy.
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8
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Marcotte GR, Miller MJ, Kunz HE, Ryan ZC, Strub MD, Vanderboom PM, Heppelmann CJ, Chau S, Von Ruff ZD, Kilroe SP, McKeen AT, Dierdorff JM, Stern JI, Nath KA, Grueter CE, Lira VA, Judge AR, Rasmussen BB, Nair KS, Lanza IR, Ebert SM, Adams CM. GADD45A is a mediator of mitochondrial loss, atrophy, and weakness in skeletal muscle. JCI Insight 2023; 8:e171772. [PMID: 37815864 PMCID: PMC10721312 DOI: 10.1172/jci.insight.171772] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 10/05/2023] [Indexed: 10/12/2023] Open
Abstract
Aging and many illnesses and injuries impair skeletal muscle mass and function, but the molecular mechanisms are not well understood. To better understand the mechanisms, we generated and studied transgenic mice with skeletal muscle-specific expression of growth arrest and DNA damage inducible α (GADD45A), a signaling protein whose expression in skeletal muscle rises during aging and a wide range of illnesses and injuries. We found that GADD45A induced several cellular changes that are characteristic of skeletal muscle atrophy, including a reduction in skeletal muscle mitochondria and oxidative capacity, selective atrophy of glycolytic muscle fibers, and paradoxical expression of oxidative myosin heavy chains despite mitochondrial loss. These cellular changes were at least partly mediated by MAP kinase kinase kinase 4, a protein kinase that is directly activated by GADD45A. By inducing these changes, GADD45A decreased the mass of muscles that are enriched in glycolytic fibers, and it impaired strength, specific force, and endurance exercise capacity. Furthermore, as predicted by data from mouse models, we found that GADD45A expression in skeletal muscle was associated with muscle weakness in humans. Collectively, these findings identify GADD45A as a mediator of mitochondrial loss, atrophy, and weakness in mouse skeletal muscle and a potential target for muscle weakness in humans.
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Affiliation(s)
- George R. Marcotte
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
- University of Iowa, Iowa City, Iowa, USA
| | - Matthew J. Miller
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
- University of Iowa, Iowa City, Iowa, USA
| | - Hawley E. Kunz
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Zachary C. Ryan
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew D. Strub
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Patrick M. Vanderboom
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Carrie J. Heppelmann
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Sarah Chau
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Sean P. Kilroe
- University of Texas Medical Branch, Galveston, Texas, USA
| | - Andrew T. McKeen
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
- University of Iowa, Iowa City, Iowa, USA
| | | | | | - Karl A. Nath
- Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | - Andrew R. Judge
- University of Florida, Gainesville, Florida, USA
- Emmyon, Inc., Rochester, Minnesota, USA
| | - Blake B. Rasmussen
- University of Texas Medical Branch, Galveston, Texas, USA
- Emmyon, Inc., Rochester, Minnesota, USA
- University of Texas Health Science Center, San Antonio, Texas, USA
| | - K. Sreekumaran Nair
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Ian R. Lanza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Scott M. Ebert
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Emmyon, Inc., Rochester, Minnesota, USA
| | - Christopher M. Adams
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Emmyon, Inc., Rochester, Minnesota, USA
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9
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Miller MJ, Marcotte GR, Basisty N, Wehrfritz C, Ryan ZC, Strub MD, McKeen AT, Stern JI, Nath KA, Rasmussen BB, Judge AR, Schilling B, Ebert SM, Adams CM. The transcription regulator ATF4 is a mediator of skeletal muscle aging. GeroScience 2023; 45:2525-2543. [PMID: 37014538 PMCID: PMC10071239 DOI: 10.1007/s11357-023-00772-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 03/10/2023] [Indexed: 04/05/2023] Open
Abstract
Aging slowly erodes skeletal muscle strength and mass, eventually leading to profound functional deficits and muscle atrophy. The molecular mechanisms of skeletal muscle aging are not well understood. To better understand mechanisms of muscle aging, we investigated the potential role of ATF4, a transcription regulatory protein that can rapidly promote skeletal muscle atrophy in young animals deprived of adequate nutrition or activity. To test the hypothesis that ATF4 may be involved in skeletal muscle aging, we studied fed and active muscle-specific ATF4 knockout mice (ATF4 mKO mice) at 6 months of age, when wild-type mice have achieved peak muscle mass and function, and at 22 months of age, when wild-type mice have begun to manifest age-related muscle atrophy and weakness. We found that 6-month-old ATF4 mKO mice develop normally and are phenotypically indistinguishable from 6-month-old littermate control mice. However, as ATF4 mKO mice become older, they exhibit significant protection from age-related declines in strength, muscle quality, exercise capacity, and muscle mass. Furthermore, ATF4 mKO muscles are protected from some of the transcriptional changes characteristic of normal muscle aging (repression of certain anabolic mRNAs and induction of certain senescence-associated mRNAs), and ATF4 mKO muscles exhibit altered turnover of several proteins with important roles in skeletal muscle structure and metabolism. Collectively, these data suggest ATF4 as an essential mediator of skeletal muscle aging and provide new insight into a degenerative process that impairs the health and quality of life of many older adults.
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Affiliation(s)
- Matthew J Miller
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- University of Iowa, Iowa City, IA, USA
| | - George R Marcotte
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- University of Iowa, Iowa City, IA, USA
| | - Nathan Basisty
- Buck Institute for Research on Aging, Novato, CA, USA
- National Institute on Aging, NIH, Baltimore, MD, USA
| | | | - Zachary C Ryan
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Matthew D Strub
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | | | - Jennifer I Stern
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Karl A Nath
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Blake B Rasmussen
- University of Texas Medical Branch, Galveston, TX, USA
- Emmyon, Inc., Rochester, MN, USA
| | - Andrew R Judge
- University of Florida, Gainesville, FL, USA
- Emmyon, Inc., Rochester, MN, USA
| | | | - Scott M Ebert
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
- Emmyon, Inc., Rochester, MN, USA.
| | - Christopher M Adams
- Division of Endocrinology, Diabetes, Metabolism and Nutrition, Departments of Medicine and Biochemistry and Molecular Biology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
- Emmyon, Inc., Rochester, MN, USA.
- Iowa City Veterans Affairs Medical Center, Iowa City, IA, USA.
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10
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Implications of mitochondrial fusion and fission in skeletal muscle mass and health. Semin Cell Dev Biol 2023; 143:46-53. [PMID: 35168898 DOI: 10.1016/j.semcdb.2022.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/17/2022] [Accepted: 02/08/2022] [Indexed: 12/12/2022]
Abstract
The continuous dynamic reshaping of mitochondria by fusion and fission events is critical to keep mitochondrial quality and function under control in response to changes in energy and stress. Maintaining a functional, highly interconnected mitochondrial reticulum ensures rapid energy production and distribution. Moreover, mitochondrial networks act as dynamic signaling hub to adapt to the metabolic demands imposed by contraction, energy expenditure, and general metabolism. However, excessive mitochondrial fusion or fission results in the disruption of the skeletal muscle mitochondrial network integrity and activates a retrograde response from mitochondria to the nucleus, leading to muscle atrophy, weakness and influencing whole-body homeostasis. These actions are mediated via the secretion of mitochondrial-stress myokines such as FGF21 and GDF15. Here we will summarize recent discoveries in the role of mitochondrial fusion and fission in the control of muscle mass and in regulating physiological homeostasis and disease progression.
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11
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Cai C, Zhang L, Liu X, Li J, Ma Y, Jiang R, Li Z, Li G, Tian Y, Kang X, Han R. Carcass composition, meat quality, leg muscle status, and its mRNA expression profile in broilers affected by valgus-varus deformity. Poult Sci 2023; 102:102682. [PMID: 37120872 PMCID: PMC10172705 DOI: 10.1016/j.psj.2023.102682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/22/2023] [Accepted: 03/26/2023] [Indexed: 04/08/2023] Open
Abstract
Valgus-varus deformity (VVD) is a common leg disease in commercial broilers, which seriously affects animal welfare and causes economic losses. Up to now, most of the studies on VVD have been on skeleton, whereas there are fewer studies on VVD muscle. In this study, carcass composition and meat quality of 35-day-old normal and VVD Cobb broilers assess the effect of VVD on broiler growth. Molecular biology, morphology, and RNA sequencing (RNA-seq) were used to study the difference between normal and VVD gastrocnemius muscle. In comparison with the normal broilers, the breast muscle and leg muscle of the VVD broilers had lower shear force, notably lower crude protein, lower water content, cooking loss, and deeper meat color (P < 0.05). The morphological results showed that the weight of skeletal muscle was significantly higher in the normal broilers than that in the VVD broilers (P < 0.01), the diameter and area of myofibrils in the affected VVD were smaller than in the normal broilers (P < 0.01). Quantitative real-time PCR (qPCR) of gastrocnemius muscle revealed that the expression of myasthenic marker genes, fast myofiber marker genes, and apoptosis-related factors were significantly higher in the VVD broilers than in the normal broilers (P < 0.01). In total, 736 differentially expressed genes (DEGs) were identified firstly in the normal and VVD leg muscle by RNA-seq. Gene ontology (GO) enrichment indicated that these DEGs were mainly involved in the multicellular organismal process and anatomical structure development. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs are significantly enriched in proteasome. Protein interaction analysis obtained that DEGs with high interaction were proteasome-related coding genes and ubiquitin-related genes, these DEGs were closely associated with muscle atrophy. These show that VVD has an adverse effect on growth characteristics, slaughter characteristics, and meat quality in broilers, which may cause leg muscle atrophy. This study provides some reference values and basis for studying the pathogenesis of VVD in broilers.
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Affiliation(s)
- Chunxia Cai
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Lujie Zhang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Xinxin Liu
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Jianzeng Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Yanchao Ma
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Ruirui Jiang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Zhuanjian Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Guoxi Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Yadong Tian
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China
| | - Xiangtao Kang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China; The Shennong Laboratory, Zhengzhou, 450002, China
| | - Ruili Han
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, 450046, China; Key Laboratory of Livestock and Poultry Resources (Poultry) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Zhengzhou, 450046, China; The Shennong Laboratory, Zhengzhou, 450002, China.
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12
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MYTHO is a novel regulator of skeletal muscle autophagy and integrity. Nat Commun 2023; 14:1199. [PMID: 36864049 PMCID: PMC9981687 DOI: 10.1038/s41467-023-36817-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 02/17/2023] [Indexed: 03/04/2023] Open
Abstract
Autophagy is a critical process in the regulation of muscle mass, function and integrity. The molecular mechanisms regulating autophagy are complex and still partly understood. Here, we identify and characterize a novel FoxO-dependent gene, d230025d16rik which we named Mytho (Macroautophagy and YouTH Optimizer), as a regulator of autophagy and skeletal muscle integrity in vivo. Mytho is significantly up-regulated in various mouse models of skeletal muscle atrophy. Short term depletion of MYTHO in mice attenuates muscle atrophy caused by fasting, denervation, cancer cachexia and sepsis. While MYTHO overexpression is sufficient to trigger muscle atrophy, MYTHO knockdown results in a progressive increase in muscle mass associated with a sustained activation of the mTORC1 signaling pathway. Prolonged MYTHO knockdown is associated with severe myopathic features, including impaired autophagy, muscle weakness, myofiber degeneration, and extensive ultrastructural defects, such as accumulation of autophagic vacuoles and tubular aggregates. Inhibition of the mTORC1 signaling pathway in mice using rapamycin treatment attenuates the myopathic phenotype triggered by MYTHO knockdown. Skeletal muscles from human patients diagnosed with myotonic dystrophy type 1 (DM1) display reduced Mytho expression, activation of the mTORC1 signaling pathway and impaired autophagy, raising the possibility that low Mytho expression might contribute to the progression of the disease. We conclude that MYTHO is a key regulator of muscle autophagy and integrity.
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13
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Induction of ATF4-Regulated Atrogenes Is Uncoupled from Muscle Atrophy during Disuse in Halofuginone-Treated Mice and in Hibernating Brown Bears. Int J Mol Sci 2022; 24:ijms24010621. [PMID: 36614063 PMCID: PMC9820832 DOI: 10.3390/ijms24010621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022] Open
Abstract
Activating transcription factor 4 (ATF4) is involved in muscle atrophy through the overexpression of some atrogenes. However, it also controls the transcription of genes involved in muscle homeostasis maintenance. Here, we explored the effect of ATF4 activation by the pharmacological molecule halofuginone during hindlimb suspension (HS)-induced muscle atrophy. Firstly, we reported that periodic activation of ATF4-regulated atrogenes (Gadd45a, Cdkn1a, and Eif4ebp1) by halofuginone was not associated with muscle atrophy in healthy mice. Secondly, halofuginone-treated mice even showed reduced atrophy during HS, although the induction of the ATF4 pathway was identical to that in untreated HS mice. We further showed that halofuginone inhibited transforming growth factor-β (TGF-β) signalling, while promoting bone morphogenetic protein (BMP) signalling in healthy mice and slightly preserved protein synthesis during HS. Finally, ATF4-regulated atrogenes were also induced in the atrophy-resistant muscles of hibernating brown bears, in which we previously also reported concurrent TGF-β inhibition and BMP activation. Overall, we show that ATF4-induced atrogenes can be uncoupled from muscle atrophy. In addition, our data also indicate that halofuginone can control the TGF-β/BMP balance towards muscle mass maintenance. Whether halofuginone-induced BMP signalling can counteract the effect of ATF4-induced atrogenes needs to be further investigated and may open a new avenue to fight muscle atrophy. Finally, our study opens the way for further studies to identify well-tolerated chemical compounds in humans that are able to fine-tune the TGF-β/BMP balance and could be used to preserve muscle mass during catabolic situations.
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14
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de Vasconcelos DAA, Nachbar RT, Pinheiro CH, do Amaral CL, Crisma AR, Vitzel KF, Abreu P, Alonso-Vale MI, Lopes AB, Bento-Santos A, Falcão-Tebas F, de Santana DF, do Nascimento E, Curi R, Pithon-Curi TC, Hirabara SM, Leandro CG. Maternal low-protein diet reduces skeletal muscle protein synthesis and mass via Akt-mTOR pathway in adult rats. Front Nutr 2022; 9:947458. [PMID: 36110404 PMCID: PMC9468266 DOI: 10.3389/fnut.2022.947458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/08/2022] [Indexed: 11/24/2022] Open
Abstract
Several studies have demonstrated that a maternal low-protein diet induces long-term metabolic disorders, but the involved mechanisms are unclear. This study investigated the molecular effects of a low-protein diet during pregnancy and lactation on glucose and protein metabolism in soleus muscle isolated from adult male rats. Female rats were fed either a normal protein diet or low-protein diet during gestation and lactation. After weaning, all pups were fed a normal protein diet until the 210th day postpartum. In the 7th month of life, mass, contractile function, protein and glucose metabolism, and the Akt-mTOR pathway were measured in the soleus muscles of male pups. Dry weight and contractile function of soleus muscle in the low-protein diet group rats were found to be lower compared to the control group. Lipid synthesis was evaluated by measuring palmitate incorporation in white adipose tissue. Palmitate incorporation was higher in the white adipose tissue of the low-protein diet group. When incubated soleus muscles were stimulated with insulin, protein synthesis, total amino acid incorporation and free amino acid content, glucose incorporation and uptake, and glycogen synthesis were found to be reduced in low-protein diet group rats. Fasting glycemia was higher in the low-protein diet group. These metabolic changes were associated with a decrease in Akt and GSK-3β signaling responses to insulin and a reduction in RPS6 in the absence of the hormone. There was also notably lower expression of Akt in the isolated soleus muscle of low-protein diet group rats. This study is the first to demonstrate how maternal diet restriction can reduce skeletal muscle protein and mass by downregulating the Akt-mTOR pathway in adulthood.
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Affiliation(s)
- Diogo Antonio Alves de Vasconcelos
- Department of Nutrition, Center of Health Sciences, Federal University of Pernambuco, Recife, Brazil
- Post-graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Vitória de Santo Antão, Vitória de Santo Antão, Brazil
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- *Correspondence: Diogo Antonio Alves de Vasconcelos,
| | - Renato Tadeu Nachbar
- Quebec Heart and Lung Institute Research Center, Laval University, Quebec City, QC, Canada
| | - Carlos Hermano Pinheiro
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Cátia Lira do Amaral
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Amanda Rabello Crisma
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Kaio Fernando Vitzel
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- School of Health Sciences, College of Health, Massey University, Auckland, New Zealand
| | - Phablo Abreu
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Maria Isabel Alonso-Vale
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Andressa Bolsoni Lopes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Adriano Bento-Santos
- Post-graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Vitória de Santo Antão, Vitória de Santo Antão, Brazil
| | - Filippe Falcão-Tebas
- The Ritchie Centre, Hudson Institute of Medical Research, Department of Obstetrics and Gynaecology, Monash University, Melbourne, VIC, Australia
| | - David Filipe de Santana
- Post-graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Vitória de Santo Antão, Vitória de Santo Antão, Brazil
| | - Elizabeth do Nascimento
- Department of Nutrition, Center of Health Sciences, Federal University of Pernambuco, Recife, Brazil
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- Interdisciplinary Post-graduate Program in Health Sciences, Cruzeiro do Sul University, São Paulo, Brazil
| | - Tania Cristina Pithon-Curi
- Interdisciplinary Post-graduate Program in Health Sciences, Cruzeiro do Sul University, São Paulo, Brazil
| | - Sandro Massao Hirabara
- Interdisciplinary Post-graduate Program in Health Sciences, Cruzeiro do Sul University, São Paulo, Brazil
| | - Carol Góis Leandro
- Post-graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Vitória de Santo Antão, Vitória de Santo Antão, Brazil
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15
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Dominant-negative p53-overexpression in skeletal muscle induces cell death and fiber atrophy in rats. Cell Death Dis 2022; 13:716. [PMID: 35977948 PMCID: PMC9385859 DOI: 10.1038/s41419-022-05160-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 01/21/2023]
Abstract
The tumor suppressor p53 is thought to play a key role in the maintenance of cell size and homeostasis, but relatively little is known about its role in skeletal muscle. Based on its ability to suppress cell growth, we hypothesized that inhibiting the function of wild-type p53 through the overexpression of a dominant-negative p53 mutant (DDp53) could result in muscle fiber hypertrophy. To test this hypothesis, we electroporated adult rat tibialis anterior muscles with DDp53 and collected the tissue three weeks later. We confirmed successful overexpression of DDp53 on a histological and biochemical level and found pronounced changes to muscle architecture, metabolism, and molecular signaling. Muscle mass, fiber cross-sectional area, and fiber diameter significantly decreased with DDp53 overexpression. We found histopathological changes in DDp53 transfected muscle which were accompanied by increased levels of proteins that are associated with membrane damage and repair. In addition, DDp53 decreased oxidative phosphorylation complex I and V protein levels, and despite its negative effects on muscle mass and fiber size, caused an increase in muscle protein synthesis as assessed via the SUnSET technique. Interestingly, the increase in muscle protein synthesis was concomitant with a decrease in phospho-S6K1 (Thr389). Furthermore, the muscle wasting in the DDp53 electroporated leg was accompanied by a decrease in global protein ubiquitination and an increase in proteasome activity. In conclusion, overexpression of a dominant-negative p53 mutant in skeletal muscle results in decreased muscle mass, myofiber size, histological muscle damage, a metabolic phenotype, and perturbed homeostasis between muscle protein synthesis and degradation.
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16
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Zolfaghari M, Faramarzi M, Hedayati M, Ghaffari M. The effect of resistance and endurance training with ursolic acid on atrophy-related biomarkers in muscle tissue of diabetic male rats induced by streptozotocin and a high-fat diet. J Food Biochem 2022; 46:e14202. [PMID: 35593021 DOI: 10.1111/jfbc.14202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 04/05/2022] [Accepted: 04/11/2022] [Indexed: 12/22/2022]
Abstract
In this study, the effect of resistance and endurance training with/without ursolic acid supplementation was evaluated to identify atrophy-related biomarkers in elderly rats induced by diabetes and a high-fat diet (HFD) based on in silico analysis algorithms and pharmaceutical methods. The visualizer software found differential gene expression levels in skeletal muscle atrophy via computed hub gene network parameters. Also, the impact of ursolic acid, as a potent inducer of the Trp53 protein in ameliorating decreased muscle mass, was analyzed in diabetic rats. Fifty-six-old male Wistar rats were randomly assigned into seven groups, including healthy control (Control), diabetic control (DM), Ursolic acid supplementation (UA), resistance training (RT), endurance training (ET), resistance training+ Ursolic acid supplementation (RT + U), and endurance training in combination with Ursolic acid supplementation (ET + U). Exercise intervention included 8 weeks of resistance or endurance training programs. Biomedical informatic outputs determined the P53 signaling pathway as a remarkable causative factor in the pathomechanism of atrophy. In addition, the results demonstrated that exercise and supplementation of UA impeded the interactions among p53/ATF4/p21. Moreover, ET and ursolic acid had a synergetic effect on the signaling pathway of p53/ATF4/p21 and probably could inhibit the aging process and modulate the p53/ATF4/p21 molecular pathway. The interaction between UA and endurance exercise significantly modified the activity of the p53/ATF4/p21 signaling pathway. Based on in silico studies, the p53/ATF4/p21 pathway plays an essential role in aging, and the inhibition of this pathway would be beneficial in decelerating the aging process. PRACTICAL APPLICATIONS: Ursolic acid (UA) is a natural pentacyclic triterpenoid carboxylic acid found in apples (a major compound of apple wax) and other fruits; it is known to improve skeletal muscle function and reduce the muscular atrophy pathways. We indicated that p53/ATF4/p21 signaling is an essential factor in aging, and the suppression of this pathway could be beneficial in the deceleration of the aging process. Therefore, this work would shed light on understanding the effect of exercise and nutrition interventions on preventing atrophy markers of skeletal muscle in diabetic rats. Further studies are needed to seek the precise mechanism of the synergism between UA and exercise in ameliorating atrophy markers.
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Affiliation(s)
- Maryam Zolfaghari
- Department of Sport Sciences, Shahrekord University, Shahrekord, Iran
| | - Mohammad Faramarzi
- Faculty of Sport Sciences, Department of Exercise Physiology, University of Isfahan, Isfahan, Iran
| | - Mehdi Hedayati
- Cellular and Molecular Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehdi Ghaffari
- Department of Sport Sciences, Shahrekord University, Shahrekord, Iran
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17
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Xu Q, Li J, Wu Y, Zhou W, Xu Z. Colorectal Cancer Chemotherapy Drug Bevacizumab May Induce Muscle Atrophy Through CDKN1A and TIMP4. Front Oncol 2022; 12:897495. [PMID: 35847900 PMCID: PMC9283830 DOI: 10.3389/fonc.2022.897495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/04/2022] [Indexed: 11/21/2022] Open
Abstract
The muscle in the organism has the function of regulating metabolism. Long-term muscle inactivity or the occurrence of chronic inflammatory diseases are easy to induce muscle atrophy. Bevacizumab is an antiangiogenic drug that prevents the formation of neovascularization by inhibiting the activation of VEGF signaling pathway. It is used in the first-line treatment of many cancers in clinic. Studies have shown that the use of bevacizumab in the treatment of tumors can cause muscle mass loss and may induce muscle atrophy. Based on bioinformatics analysis, this study sought the relationship and influence mechanism between bevacizumab and muscle atrophy. The differences of gene and sample expression between bevacizumab treated group and control group were studied by RNA sequencing. WGCNA is used to find gene modules related to bevacizumab administration and explore biological functions through metascape. Differential analysis was used to analyze the difference of gene expression between the administration group and the control group in different muscle tissues. The key genes timp4 and CDKN1A were obtained through Venn diagram, and then GSEA was used to explore their biological functions in RNA sequencing data and geo chip data. This study studied the role of bevacizumab in muscle through the above methods, preliminarily determined that timp4 and CDKN1A may be related to muscle atrophy, and further explored their functional mechanism in bevacizumab myotoxicity.
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18
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Carraro V, Combaret L, Coudy-Gandilhon C, Parry L, Averous J, Maurin AC, Jousse C, Voyard G, Fafournoux P, Papet I, Bruhat A. Activation of the eIF2α-ATF4 Pathway by Chronic Paracetamol Treatment Is Prevented by Dietary Supplementation with Cysteine. Int J Mol Sci 2022; 23:ijms23137196. [PMID: 35806203 PMCID: PMC9266523 DOI: 10.3390/ijms23137196] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 02/01/2023] Open
Abstract
Chronic treatment with acetaminophen (APAP) induces cysteine (Cys) and glutathione (GSH) deficiency which leads to adverse metabolic effects including muscle atrophy. Mammalian cells respond to essential amino acid deprivation through the phosphorylation of the eukaryotic translation initiation factor 2α (eIF2α). Phosphorylated eIF2α leads to the recruitment of activating transcription factor 4 (ATF4) to specific CCAAT/enhancer-binding protein-ATF response element (CARE) located in the promoters of target genes. Our purpose was to study the activation of the eIF2α-ATF4 pathway in response to APAP-induced Cys deficiency, as well as the potential contribution of the eIF2α kinase GCN2 and the effect of dietary supplementation with Cys. Our results showed that chronic treatment with APAP activated both GCN2 and PERK eIF2α kinases and downstream target genes in the liver. Activation of the eIF2α-ATF4 pathway in skeletal muscle was accompanied by muscle atrophy even in the absence of GCN2. The dietary supplementation with cysteine reversed APAP-induced decreases in plasma-free Cys, liver GSH, muscle mass, and muscle GSH. Our new findings demonstrate that dietary Cys supplementation also reversed the APAP-induced activation of GCN2 and PERK and downstream ATF4-target genes in the liver.
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Affiliation(s)
- Valérie Carraro
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Lydie Combaret
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Cécile Coudy-Gandilhon
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Laurent Parry
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Julien Averous
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Anne-Catherine Maurin
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Céline Jousse
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Guillaume Voyard
- Université Clermont Auvergne, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France;
| | - Pierre Fafournoux
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
| | - Isabelle Papet
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
- Correspondence: (I.P.); (A.B.)
| | - Alain Bruhat
- Université Clermont Auvergne, INRAE, UNH Unité de Nutrition Humaine, UMR1019, F-63000 Clermont-Ferrand, France; (V.C.); (L.C.); (C.C.-G.); (L.P.); (J.A.); (A.-C.M.); (C.J.); (P.F.)
- Correspondence: (I.P.); (A.B.)
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19
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Kny M, Fielitz J. Hidden Agenda - The Involvement of Endoplasmic Reticulum Stress and Unfolded Protein Response in Inflammation-Induced Muscle Wasting. Front Immunol 2022; 13:878755. [PMID: 35615361 PMCID: PMC9124858 DOI: 10.3389/fimmu.2022.878755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Critically ill patients at the intensive care unit (ICU) often develop a generalized weakness, called ICU-acquired weakness (ICUAW). A major contributor to ICUAW is muscle atrophy, a loss of skeletal muscle mass and function. Skeletal muscle assures almost all of the vital functions of our body. It adapts rapidly in response to physiological as well as pathological stress, such as inactivity, immobilization, and inflammation. In response to a reduced workload or inflammation muscle atrophy develops. Recent work suggests that adaptive or maladaptive processes in the endoplasmic reticulum (ER), also known as sarcoplasmic reticulum, contributes to this process. In muscle cells, the ER is a highly specialized cellular organelle that assures calcium homeostasis and therefore muscle contraction. The ER also assures correct folding of proteins that are secreted or localized to the cell membrane. Protein folding is a highly error prone process and accumulation of misfolded or unfolded proteins can cause ER stress, which is counteracted by the activation of a signaling network known as the unfolded protein response (UPR). Three ER membrane residing molecules, protein kinase R-like endoplasmic reticulum kinase (PERK), inositol requiring protein 1a (IRE1a), and activating transcription factor 6 (ATF6) initiate the UPR. The UPR aims to restore ER homeostasis by reducing overall protein synthesis and increasing gene expression of various ER chaperone proteins. If ER stress persists or cannot be resolved cell death pathways are activated. Although, ER stress-induced UPR pathways are known to be important for regulation of skeletal muscle mass and function as well as for inflammation and immune response its function in ICUAW is still elusive. Given recent advances in the development of ER stress modifying molecules for neurodegenerative diseases and cancer, it is important to know whether or not therapeutic interventions in ER stress pathways have favorable effects and these compounds can be used to prevent or treat ICUAW. In this review, we focus on the role of ER stress-induced UPR in skeletal muscle during critical illness and in response to predisposing risk factors such as immobilization, starvation and inflammation as well as ICUAW treatment to foster research for this devastating clinical problem.
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Affiliation(s)
- Melanie Kny
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Jens Fielitz
- Department of Molecular Cardiology, DZHK (German Center for Cardiovascular Research), Partner Site, Greifswald, Germany
- Department of Internal Medicine B, Cardiology, University Medicine Greifswald, Greifswald, Germany
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20
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Vásquez-Trincado C, Dunn J, Han JI, Hymms B, Tamaroff J, Patel M, Nguyen S, Dedio A, Wade K, Enigwe C, Nichtova Z, Lynch DR, Csordas G, McCormack SE, Seifert EL. Frataxin deficiency lowers lean mass and triggers the integrated stress response in skeletal muscle. JCI Insight 2022; 7:e155201. [PMID: 35531957 PMCID: PMC9090249 DOI: 10.1172/jci.insight.155201] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 03/09/2022] [Indexed: 12/03/2022] Open
Abstract
Friedreich's ataxia (FRDA) is an inherited disorder caused by reduced levels of frataxin (FXN), which is required for iron-sulfur cluster biogenesis. Neurological and cardiac comorbidities are prominent and have been a major focus of study. Skeletal muscle has received less attention despite indications that FXN loss affects it. Here, we show that lean mass is lower, whereas body mass index is unaltered, in separate cohorts of adults and children with FRDA. In adults, lower lean mass correlated with disease severity. To further investigate FXN loss in skeletal muscle, we used a transgenic mouse model of whole-body inducible and progressive FXN depletion. There was little impact of FXN loss when FXN was approximately 20% of control levels. When residual FXN was approximately 5% of control levels, muscle mass was lower along with absolute grip strength. When we examined mechanisms that can affect muscle mass, only global protein translation was lower, accompanied by integrated stress response (ISR) activation. Also in mice, aerobic exercise training, initiated prior to the muscle mass difference, improved running capacity, yet, muscle mass and the ISR remained as in untrained mice. Thus, FXN loss can lead to lower lean mass, with ISR activation, both of which are insensitive to exercise training.
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Affiliation(s)
- César Vásquez-Trincado
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Julia Dunn
- Division of Endocrinology and Diabetes and
| | - Ji In Han
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Briyanna Hymms
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | | | - Monika Patel
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | | | - Anna Dedio
- Division of Endocrinology and Diabetes and
| | | | | | - Zuzana Nichtova
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - David R. Lynch
- Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Neurology and
| | - Gyorgy Csordas
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Shana E. McCormack
- Division of Endocrinology and Diabetes and
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Erin L. Seifert
- Department of Pathology, Anatomy, and Cell Biology, Sidney Kimmel Medical College and
- MitoCare Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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21
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Hughes DC, Hardee JP, Waddell DS, Goodman CA. CORP: Gene delivery into murine skeletal muscle using in vivo electroporation. J Appl Physiol (1985) 2022; 133:41-59. [PMID: 35511722 DOI: 10.1152/japplphysiol.00088.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The strategy of gene delivery into skeletal muscles has provided exciting avenues in identifying new potential therapeutics towards muscular disorders and addressing basic research questions in muscle physiology through overexpression and knockdown studies. In vivo electroporation methodology offers a simple, rapidly effective technique for the delivery of plasmid DNA into post-mitotic skeletal muscle fibers and the ability to easily explore the molecular mechanisms of skeletal muscle plasticity. The purpose of this review is to describe how to robustly electroporate plasmid DNA into different hindlimb muscles of rodent models. Further, key parameters (e.g., voltage, hyaluronidase, plasmid concentration) which contribute to the successful introduction of plasmid DNA into skeletal muscle fibers will be discussed. In addition, details on processing tissue for immunohistochemistry and fiber cross-sectional area (CSA) analysis will be outlined. The overall goal of this review is to provide the basic and necessary information needed for successful implementation of in vivo electroporation of plasmid DNA and thus open new avenues of discovery research in skeletal muscle physiology.
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Affiliation(s)
- David C Hughes
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Justin P Hardee
- Centre for Muscle Research (CMR), Department of Anatomy and Physiology, The University of Melbourne, Victoria, Australia
| | - David S Waddell
- Department of Biology, University of North Florida, Jacksonville, FL, United States
| | - Craig A Goodman
- Centre for Muscle Research (CMR), Department of Anatomy and Physiology, The University of Melbourne, Victoria, Australia
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22
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Ebert SM, Rasmussen BB, Judge AR, Judge SM, Larsson L, Wek RC, Anthony TG, Marcotte GR, Miller MJ, Yorek MA, Vella A, Volpi E, Stern JI, Strub MD, Ryan Z, Talley JJ, Adams CM. Biology of Activating Transcription Factor 4 (ATF4) and Its Role in Skeletal Muscle Atrophy. J Nutr 2022; 152:926-938. [PMID: 34958390 PMCID: PMC8970988 DOI: 10.1093/jn/nxab440] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/17/2021] [Accepted: 12/23/2021] [Indexed: 12/30/2022] Open
Abstract
Activating transcription factor 4 (ATF4) is a multifunctional transcription regulatory protein in the basic leucine zipper superfamily. ATF4 can be expressed in most if not all mammalian cell types, and it can participate in a variety of cellular responses to specific environmental stresses, intracellular derangements, or growth factors. Because ATF4 is involved in a wide range of biological processes, its roles in human health and disease are not yet fully understood. Much of our current knowledge about ATF4 comes from investigations in cultured cell models, where ATF4 was originally characterized and where further investigations continue to provide new insights. ATF4 is also an increasingly prominent topic of in vivo investigations in fully differentiated mammalian cell types, where our current understanding of ATF4 is less complete. Here, we review some important high-level concepts and questions concerning the basic biology of ATF4. We then discuss current knowledge and emerging questions about the in vivo role of ATF4 in one fully differentiated cell type, mammalian skeletal muscle fibers.
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Affiliation(s)
- Scott M Ebert
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
- Emmyon, Inc., Rochester, MN, USA
| | - Blake B Rasmussen
- Emmyon, Inc., Rochester, MN, USA
- Department of Nutrition, Metabolism and Rehabilitation Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Andrew R Judge
- Emmyon, Inc., Rochester, MN, USA
- Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - Sarah M Judge
- Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - Lars Larsson
- Department of Physiology and Pharmacology, Karolinska, Stockholm, Sweden
| | - Ronald C Wek
- Department of Biochemistry and Molecular Biology, Indiana University, Indianapolis, IN, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences, Rutgers University, New Brunswick, NJ, USA
| | - George R Marcotte
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA
| | - Matthew J Miller
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA
| | - Mark A Yorek
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA
- Department of Internal Medicine, Iowa City VA Medical Center, Iowa City, IA, USA
| | - Adrian Vella
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
- Emmyon, Inc., Rochester, MN, USA
| | - Elena Volpi
- Department of Nutrition, Metabolism and Rehabilitation Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Jennifer I Stern
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
| | - Matthew D Strub
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
| | - Zachary Ryan
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
| | | | - Christopher M Adams
- Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
- Emmyon, Inc., Rochester, MN, USA
- Department of Internal Medicine, Iowa City VA Medical Center, Iowa City, IA, USA
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23
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Copola AGL, Dos Santos ÍGD, Coutinho LL, Del-Bem LEV, de Almeida Campos-Junior PH, da Conceição IMCA, Nogueira JM, do Carmo Costa A, Silva GAB, Jorge EC. Transcriptomic characterization of the molecular mechanisms induced by RGMa during skeletal muscle nuclei accretion and hypertrophy. BMC Genomics 2022; 23:188. [PMID: 35255809 PMCID: PMC8902710 DOI: 10.1186/s12864-022-08396-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 02/15/2022] [Indexed: 12/02/2022] Open
Abstract
Background The repulsive guidance molecule a (RGMa) is a GPI-anchor axon guidance molecule first found to play important roles during neuronal development. RGMa expression patterns and signaling pathways via Neogenin and/or as BMP coreceptors indicated that this axon guidance molecule could also be working in other processes and diseases, including during myogenesis. Previous works from our research group have consistently shown that RGMa is expressed in skeletal muscle cells and that its overexpression induces both nuclei accretion and hypertrophy in muscle cell lineages. However, the cellular components and molecular mechanisms induced by RGMa during the differentiation of skeletal muscle cells are poorly understood. In this work, the global transcription expression profile of RGMa-treated C2C12 myoblasts during the differentiation stage, obtained by RNA-seq, were reported. Results RGMa treatment could modulate the expression pattern of 2,195 transcripts in C2C12 skeletal muscle, with 943 upregulated and 1,252 downregulated. Among them, RGMa interfered with the expression of several RNA types, including categories related to the regulation of RNA splicing and degradation. The data also suggested that nuclei accretion induced by RGMa could be due to their capacity to induce the expression of transcripts related to ‘adherens junsctions’ and ‘extracellular-cell adhesion’, while RGMa effects on muscle hypertrophy might be due to (i) the activation of the mTOR-Akt independent axis and (ii) the regulation of the expression of transcripts related to atrophy. Finally, RGMa induced the expression of transcripts that encode skeletal muscle structural proteins, especially from sarcolemma and also those associated with striated muscle cell differentiation. Conclusions These results provide comprehensive knowledge of skeletal muscle transcript changes and pathways in response to RGMa. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08396-w.
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Affiliation(s)
- Aline Gonçalves Lio Copola
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil
| | - Íria Gabriela Dias Dos Santos
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil
| | - Luiz Lehmann Coutinho
- Departamento de Zootecnia, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brasil
| | - Luiz Eduardo Vieira Del-Bem
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brasil
| | | | | | - Júlia Meireles Nogueira
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil
| | - Alinne do Carmo Costa
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil
| | - Gerluza Aparecida Borges Silva
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil
| | - Erika Cristina Jorge
- Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31.270-901, Brasil.
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24
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Oyabu M, Takigawa K, Mizutani S, Hatazawa Y, Fujita M, Ohira Y, Sugimoto T, Suzuki O, Tsuchiya K, Suganami T, Ogawa Y, Ishihara K, Miura S, Kamei Y. FOXO1 cooperates with C/EBPδ and ATF4 to regulate skeletal muscle atrophy transcriptional program during fasting. FASEB J 2022; 36:e22152. [DOI: 10.1096/fj.202101385rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022]
Affiliation(s)
- Mamoru Oyabu
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Kaho Takigawa
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Sako Mizutani
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Yukino Hatazawa
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Mariko Fujita
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Yuto Ohira
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Takumi Sugimoto
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
| | - Osamu Suzuki
- Laboratory of Animal Models for Human Diseases National Institutes of Biomedical Innovation, Health and Nutrition Osaka Japan
| | - Kyoichiro Tsuchiya
- Third Department of Internal Medicine Interdisciplinary Graduate School of Medicine and Engineering University of Yamanashi Yamanashi Japan
| | - Takayoshi Suganami
- Department of Molecular Medicine and Metabolism Research Institute of Environmental Medicine Nagoya University Nagoya Japan
| | - Yoshihiro Ogawa
- Department of Medicine and Bioregulatory Science Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Kengo Ishihara
- Department of Food Science and Human Nutrition Faculty of Agriculture Ryukoku University Shiga Japan
| | - Shinji Miura
- Graduate School of Nutritional and Environmental Sciences University of Shizuoka Shizuoka Japan
| | - Yasutomi Kamei
- Laboratory of Molecular Nutrition Graduate School of Life and Environmental Sciences Kyoto Prefectural University Kyoto Japan
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25
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Zumbaugh MD, Yen CN, Bodmer JS, Shi H, Gerrard DE. Skeletal Muscle O-GlcNAc Transferase Action on Global Metabolism Is Partially Mediated Through Interleukin-15. Front Physiol 2021; 12:682052. [PMID: 34326778 PMCID: PMC8313823 DOI: 10.3389/fphys.2021.682052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/24/2021] [Indexed: 01/11/2023] Open
Abstract
Besides its roles in locomotion and thermogenesis, skeletal muscle plays a significant role in global glucose metabolism and insulin sensitivity through complex nutrient sensing networks. Our previous work showed that the muscle-specific ablation of O-GlcNAc transferase (OGT) led to a lean phenotype through enhanced interleukin-15 (IL-15) expression. We also showed OGT epigenetically modified and repressed the Il15 promoter. However, whether there is a causal relationship between OGT ablation-induced IL-15 secretion and the lean phenotype remains unknown. To address this question, we generated muscle specific OGT and interleukin-15 receptor alpha subunit (IL-15rα) double knockout mice (mDKO). Deletion of IL-15rα in skeletal muscle impaired IL-15 secretion. When fed with a high-fat diet, mDKO mice were no longer protected against HFD-induced obesity compared to wild-type mice. After 22 weeks of HFD feeding, mDKO mice had an intermediate body weight and glucose sensitivity compared to wild-type and OGT knockout mice. Taken together, these data suggest that OGT action is partially mediated by muscle IL-15 production and provides some clarity into how disrupting the O-GlcNAc nutrient signaling pathway leads to a lean phenotype. Further, our work suggests that interfering with the OGT-IL15 nutrient sensing axis may provide a new avenue for combating obesity and metabolic disorders.
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Affiliation(s)
- Morgan D Zumbaugh
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Con-Ning Yen
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Jocelyn S Bodmer
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Hao Shi
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - David E Gerrard
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
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26
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Ma W, Cai Y, Shen Y, Chen X, Zhang L, Ji Y, Chen Z, Zhu J, Yang X, Sun H. HDAC4 Knockdown Alleviates Denervation-Induced Muscle Atrophy by Inhibiting Myogenin-Dependent Atrogene Activation. Front Cell Neurosci 2021; 15:663384. [PMID: 34276308 PMCID: PMC8278478 DOI: 10.3389/fncel.2021.663384] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/13/2021] [Indexed: 01/07/2023] Open
Abstract
Denervation can activate the catabolic pathway in skeletal muscle and lead to progressive skeletal muscle atrophy. At present, there is no effective treatment for muscle atrophy. Histone deacetylase 4 (HDAC4) has recently been found to be closely related to muscle atrophy, but the underlying mechanism of HDAC4 in denervation-induced muscle atrophy have not been described clearly yet. In this study, we found that the expression of HDAC4 increased significantly in denervated skeletal muscle. HDAC4 inhibition can effectively diminish denervation-induced muscle atrophy, reduce the expression of muscle specific E3 ubiquitin ligase (MuRF1 and MAFbx) and autophagy related proteins (Atg7, LC3B, PINK1 and BNIP3), inhibit the transformation of type I fibers to type II fibers, and enhance the expression of SIRT1 and PGC-1 α. Transcriptome sequencing and bioinformatics analysis was performed and suggested that HDAC4 may be involved in denervation-induced muscle atrophy by regulating the response to denervation involved in the regulation of muscle adaptation, cell division, cell cycle, apoptotic process, skeletal muscle atrophy, and cell differentiation. STRING analysis showed that HDAC4 may be involved in the process of muscle atrophy by directly regulating myogenin (MYOG), cell cycle inhibitor p21 (CDKN1A) and salt induced kinase 1 (SIK1). MYOG was significantly increased in denervated skeletal muscle, and MYOG inhibition could significantly alleviate denervation-induced muscle atrophy, accompanied by the decreased MuRF1 and MAFbx. MYOG overexpression could reduce the protective effect of HDAC4 inhibition on denervation-induced muscle atrophy, as evidenced by the decreased muscle mass and cross-sectional area of muscle fibers, and the increased mitophagy. Taken together, HDAC4 inhibition can alleviate denervation-induced muscle atrophy by reducing MYOG expression, and HDAC4 is also directly related to CDKN1A and SIK1 in skeletal muscle, which suggests that HDAC4 inhibitors may be a potential drug for the treatment of neurogenic muscle atrophy. These results not only enrich the molecular regulation mechanism of denervation-induced muscle atrophy, but also provide the experimental basis for HDAC4-MYOG axis as a new target for the prevention and treatment of muscular atrophy.
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Affiliation(s)
- Wenjing Ma
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yong Cai
- Department of Neurology, People's Hospital of Binhai County, Yancheng, China
| | - Yuntian Shen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xin Chen
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, China
| | - Lilei Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yanan Ji
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Zehao Chen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Jianwei Zhu
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Xiaoming Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Hualin Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
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27
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Vanhoutte D, Schips TG, Vo A, Grimes KM, Baldwin TA, Brody MJ, Accornero F, Sargent MA, Molkentin JD. Thbs1 induces lethal cardiac atrophy through PERK-ATF4 regulated autophagy. Nat Commun 2021; 12:3928. [PMID: 34168130 PMCID: PMC8225674 DOI: 10.1038/s41467-021-24215-4] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 05/31/2021] [Indexed: 02/05/2023] Open
Abstract
The thrombospondin (Thbs) family of secreted matricellular proteins are stress- and injury-induced mediators of cellular attachment dynamics and extracellular matrix protein production. Here we show that Thbs1, but not Thbs2, Thbs3 or Thbs4, induces lethal cardiac atrophy when overexpressed. Mechanistically, Thbs1 binds and activates the endoplasmic reticulum stress effector PERK, inducing its downstream transcription factor ATF4 and causing lethal autophagy-mediated cardiac atrophy. Antithetically, Thbs1-/- mice develop greater cardiac hypertrophy with pressure overload stimulation and show reduced fasting-induced atrophy. Deletion of Thbs1 effectors/receptors, including ATF6α, CD36 or CD47 does not diminish Thbs1-dependent cardiac atrophy. However, deletion of the gene encoding PERK in Thbs1 transgenic mice blunts the induction of ATF4 and autophagy, and largely corrects the lethal cardiac atrophy. Finally, overexpression of PERK or ATF4 using AAV9 gene-transfer similarly promotes cardiac atrophy and lethality. Hence, we identified Thbs1-mediated PERK-eIF2α-ATF4-induced autophagy as a critical regulator of cardiomyocyte size in the stressed heart.
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Affiliation(s)
- Davy Vanhoutte
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Tobias G Schips
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Janssen Pharmaceuticals, Spring House, PA, USA
| | - Alexander Vo
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Kelly M Grimes
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Tanya A Baldwin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Matthew J Brody
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, USA
| | - Federica Accornero
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA
| | - Michelle A Sargent
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Jeffery D Molkentin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
- Howard Hughes Medical Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
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28
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Baehr LM, Hughes DC, Lynch SA, Van Haver D, Maia TM, Marshall AG, Radoshevich L, Impens F, Waddell DS, Bodine SC. Identification of the MuRF1 Skeletal Muscle Ubiquitylome Through Quantitative Proteomics. FUNCTION (OXFORD, ENGLAND) 2021; 2:zqab029. [PMID: 34179788 PMCID: PMC8218097 DOI: 10.1093/function/zqab029] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/12/2021] [Accepted: 05/17/2021] [Indexed: 02/07/2023]
Abstract
MuRF1 (TRIM63) is a muscle-specific E3 ubiquitin ligase and component of the ubiquitin proteasome system. MuRF1 is transcriptionally upregulated under conditions that cause muscle loss, in both rodents and humans, and is a recognized marker of muscle atrophy. In this study, we used in vivo electroporation to determine whether MuRF1 overexpression alone can cause muscle atrophy and, in combination with ubiquitin proteomics, identify the endogenous MuRF1 substrates in skeletal muscle. Overexpression of MuRF1 in adult mice increases ubiquitination of myofibrillar and sarcoplasmic proteins, increases expression of genes associated with neuromuscular junction instability, and causes muscle atrophy. A total of 169 ubiquitination sites on 56 proteins were found to be regulated by MuRF1. MuRF1-mediated ubiquitination targeted both thick and thin filament contractile proteins, as well as, glycolytic enzymes, deubiquitinases, p62, and VCP. These data reveal a potential role for MuRF1 in not only the breakdown of the sarcomere but also the regulation of metabolism and other proteolytic pathways in skeletal muscle.
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Affiliation(s)
| | | | - Sarah A Lynch
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Delphi Van Haver
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - Teresa Mendes Maia
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - Andrea G Marshall
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Lilliana Radoshevich
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Francis Impens
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - David S Waddell
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
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Gallot YS, Bohnert KR. Confounding Roles of ER Stress and the Unfolded Protein Response in Skeletal Muscle Atrophy. Int J Mol Sci 2021; 22:2567. [PMID: 33806433 PMCID: PMC7961896 DOI: 10.3390/ijms22052567] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/26/2021] [Accepted: 03/03/2021] [Indexed: 12/12/2022] Open
Abstract
Skeletal muscle is an essential organ, responsible for many physiological functions such as breathing, locomotion, postural maintenance, thermoregulation, and metabolism. Interestingly, skeletal muscle is a highly plastic tissue, capable of adapting to anabolic and catabolic stimuli. Skeletal muscle contains a specialized smooth endoplasmic reticulum (ER), known as the sarcoplasmic reticulum, composed of an extensive network of tubules. In addition to the role of folding and trafficking proteins within the cell, this specialized organelle is responsible for the regulated release of calcium ions (Ca2+) into the cytoplasm to trigger a muscle contraction. Under various stimuli, such as exercise, hypoxia, imbalances in calcium levels, ER homeostasis is disturbed and the amount of misfolded and/or unfolded proteins accumulates in the ER. This accumulation of misfolded/unfolded protein causes ER stress and leads to the activation of the unfolded protein response (UPR). Interestingly, the role of the UPR in skeletal muscle has only just begun to be elucidated. Accumulating evidence suggests that ER stress and UPR markers are drastically induced in various catabolic stimuli including cachexia, denervation, nutrient deprivation, aging, and disease. Evidence indicates some of these molecules appear to be aiding the skeletal muscle in regaining homeostasis whereas others demonstrate the ability to drive the atrophy. Continued investigations into the individual molecules of this complex pathway are necessary to fully understand the mechanisms.
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Affiliation(s)
- Yann S. Gallot
- LBEPS, Univ Evry, IRBA, Université Paris Saclay, 91025 Evry, France
| | - Kyle R. Bohnert
- Kinesiology Department, St. Ambrose University, Davenport, IA 52803, USA
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30
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Xie MX, Cao XY, Zeng WA, Lai RC, Guo L, Wang JC, Xiao YB, Zhang X, Chen D, Liu XG, Zhang XL. ATF4 selectively regulates heat nociception and contributes to kinesin-mediated TRPM3 trafficking. Nat Commun 2021; 12:1401. [PMID: 33658516 PMCID: PMC7930092 DOI: 10.1038/s41467-021-21731-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 02/09/2021] [Indexed: 12/30/2022] Open
Abstract
Effective treatments for patients suffering from heat hypersensitivity are lacking, mostly due to our limited understanding of the pathogenic mechanisms underlying this disorder. In the nervous system, activating transcription factor 4 (ATF4) is involved in the regulation of synaptic plasticity and memory formation. Here, we show that ATF4 plays an important role in heat nociception. Indeed, loss of ATF4 in mouse dorsal root ganglion (DRG) neurons selectively impairs heat sensitivity. Mechanistically, we show that ATF4 interacts with transient receptor potential cation channel subfamily M member-3 (TRPM3) and mediates the membrane trafficking of TRPM3 in DRG neurons in response to heat. Loss of ATF4 also significantly decreases the current and KIF17-mediated trafficking of TRPM3, suggesting that the KIF17/ATF4/TRPM3 complex is required for the neuronal response to heat stimuli. Our findings unveil the non-transcriptional role of ATF4 in the response to heat stimuli in DRG neurons.
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Affiliation(s)
- Man-Xiu Xie
- Department of Anesthesiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, China
| | - Xian-Ying Cao
- College of Food Science and Technology, Hainan University, 58 Renmin Avenue, Haikou, China
- State Key Laboratory of Marine Resources Utilization of South China Sea, 58 Renmin Avenue, Haikou, China
| | - Wei-An Zeng
- Department of Anesthesiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, China
| | - Ren-Chun Lai
- Department of Anesthesiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, China
| | - Lan Guo
- College of Food Science and Technology, Hainan University, 58 Renmin Avenue, Haikou, China
| | - Jun-Chao Wang
- Department of Anesthesiology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng East Road, Guangzhou, China
| | - Yi-Bin Xiao
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Road 2, Guangzhou, China
| | - Xi Zhang
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Road 2, Guangzhou, China
| | - Di Chen
- College of Food Science and Technology, Hainan University, 58 Renmin Avenue, Haikou, China
| | - Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan School of Medicine of Sun Yat-sen University, 74 Zhongshan Road 2, Guangzhou, China.
| | - Xiao-Long Zhang
- Medical Research Center of Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan Rd. 2, Guangzhou, China.
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31
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Cui Q, Yang H, Gu Y, Zong C, Chen X, Lin Y, Sun H, Shen Y, Zhu J. RNA sequencing (RNA-seq) analysis of gene expression provides new insights into hindlimb unloading-induced skeletal muscle atrophy. ANNALS OF TRANSLATIONAL MEDICINE 2021; 8:1595. [PMID: 33437794 PMCID: PMC7791259 DOI: 10.21037/atm-20-7400] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background Weightlessness-induced skeletal muscle atrophy, accompanied by complex biochemical and physiological changes, has potentially damaged consequences. However, there is still an insufficient effective strategy to treat skeletal muscle atrophy. Therefore, exploring the molecular mechanisms regulating skeletal muscle atrophy and effective protection is necessary. Methods RNA sequencing (RNA-seq) analysis was used to detect differentially expressed genes (DEGs) in the soleus muscle at 12, 24, 36 hours, three days, and seven days after hindlimb unloading in rats. Pearson correlation heatmaps and principal component analysis (PCA) were applied to analyze DEGs’ expression profiles. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used for cluster analysis of DEGs. Ingenuity pathway analysis (IPA) was used to analyze specific biological processes further. Results At different time points (12, 24, 36 hours, three days, seven days) after hindlimb unloading, the expression levels of 712, 1,109, 1,433, 1,162, and 1,182 genes in rat soleus muscle were upregulated, respectively, whereas the expression levels of 1,186, 1,324, 1,632, 1,446, and 1,596 genes were downregulated, respectively. PCA revealed that rat soleus muscle showed three different transcriptional phases within seven days after hindlimb unloading. KEGG and GO annotation indicated that the first transcriptional phase primarily involved the activation of stress responses, including oxidative stress, and the inhibition of cell proliferation and angiogenesis; the second transcriptional phase primarily involved the activation of proteolytic systems and, to a certain degree, inflammatory responses; and the third transcriptional phase primarily involved extensive activation of the proteolytic system, significant inhibition of energy metabolism, and activation of the aging process and slow-to-fast muscle conversion. Conclusions Different physiological processes in rat skeletal muscles were activated sequentially after unloading. From these activated biological processes, the three transcriptional phases after skeletal muscle unloading can be successively defined as the stress response phase, the atrophic initiation phase, and the atrophic phase. Our study not only helps in the understanding of the molecular mechanisms underlying weightlessness-induced muscle atrophy but may also provide an important time window for the treatment and prevention of weightlessness-induced muscle atrophy.
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Affiliation(s)
- Qihao Cui
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Hua Yang
- Department of Neurosurgery, People's Hospital of Binhai County, Yancheng, China
| | - Yuming Gu
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Chenyu Zong
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Xin Chen
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, China
| | - Yinghao Lin
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Hualin Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yuntian Shen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Jianwei Zhu
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
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32
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Roberson PA, Mobley CB, Romero MA, Haun CT, Osburn SC, Mumford PW, Vann CG, Greer RA, Ferrando AA, Roberts MD. LAT1 Protein Content Increases Following 12 Weeks of Resistance Exercise Training in Human Skeletal Muscle. Front Nutr 2021; 7:628405. [PMID: 33521042 PMCID: PMC7840583 DOI: 10.3389/fnut.2020.628405] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 12/11/2020] [Indexed: 12/24/2022] Open
Abstract
Introduction: Amino acid transporters are essential for cellular amino acid transport and promoting protein synthesis. While previous literature has demonstrated the association of amino acid transporters and protein synthesis following acute resistance exercise and amino acid supplementation, the chronic effect of resistance exercise and supplementation on amino acid transporters is unknown. The purpose herein was to determine if amino acid transporters and amino acid metabolic enzymes were related to skeletal muscle hypertrophy following resistance exercise training with different nutritional supplementation strategies. Methods: 43 college-aged males were separated into a maltodextrin placebo (PLA, n = 12), leucine (LEU, n = 14), or whey protein concentrate (WPC, n = 17) group and underwent 12 weeks of total-body resistance exercise training. Each group's supplement was standardized for total energy and fat, and LEU and WPC supplements were standardized for total leucine (6 g/d). Skeletal muscle biopsies were obtained prior to training and ~72 h following each subject's last training session. Results: All groups increased type I and II fiber cross-sectional area (fCSA) following training (p < 0.050). LAT1 protein increased following training (p < 0.001) and increased more in PLA than LEU and WPC (p < 0.050). BCKDHα protein increased and ATF4 protein decreased following training (p < 0.001). Immunohistochemistry indicated total LAT1/fiber, but not membrane LAT1/fiber, increased with training (p = 0.003). Utilizing all groups, the change in ATF4 protein, but no other marker, trended to correlate with the change in fCSA (r = 0.314; p = 0.055); however, when regression analysis was used to delineate groups, the change in ATF4 protein best predicted the change in fCSA only in LEU (r 2 = 0.322; p = 0.043). In C2C12 myoblasts, LAT1 protein overexpression caused a paradoxical decrease in protein synthesis levels (p = 0.002) and decrease in BCKDHα protein (p = 0.001). Conclusions: Amino acid transporters and metabolic enzymes are affected by resistance exercise training, but do not appear to dictate muscle fiber hypertrophy. In fact, overexpression of LAT1 in vitro decreased protein synthesis.
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Affiliation(s)
- Paul A Roberson
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - C Brooks Mobley
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Matthew A Romero
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Cody T Haun
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Shelby C Osburn
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Petey W Mumford
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Rory A Greer
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Arny A Ferrando
- Department of Geriatrics, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AK, United States
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33
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The Interplay between Mitochondrial Morphology and Myomitokines in Aging Sarcopenia. Int J Mol Sci 2020; 22:ijms22010091. [PMID: 33374852 PMCID: PMC7796142 DOI: 10.3390/ijms22010091] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/13/2022] Open
Abstract
Sarcopenia is a chronic disease characterized by the progressive loss of skeletal muscle mass, force, and function during aging. It is an emerging public problem associated with poor quality of life, disability, frailty, and high mortality. A decline in mitochondria quality control pathways constitutes a major mechanism driving aging sarcopenia, causing abnormal organelle accumulation over a lifetime. The resulting mitochondrial dysfunction in sarcopenic muscles feedbacks systemically by releasing the myomitokines fibroblast growth factor 21 (FGF21) and growth and differentiation factor 15 (GDF15), influencing the whole-body homeostasis and dictating healthy or unhealthy aging. This review describes the principal pathways controlling mitochondrial quality, many of which are potential therapeutic targets against muscle aging, and the connection between mitochondrial dysfunction and the myomitokines FGF21 and GDF15 in the pathogenesis of aging sarcopenia.
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34
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Lo CJ, Ko YS, Chang SW, Tang HY, Huang CY, Huang YC, Ho HY, Lin CM, Cheng ML. Metabolic signatures of muscle mass loss in an elderly Taiwanese population. Aging (Albany NY) 2020; 13:944-956. [PMID: 33410783 PMCID: PMC7834982 DOI: 10.18632/aging.202209] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 10/05/2020] [Indexed: 12/25/2022]
Abstract
To identify the association between metabolites and muscle mass in 305 elderly Taiwanese subjects, we conducted a multivariate analysis of 153 plasma samples. Based on appendicular skeletal muscle mass index (ASMI) quartiles, female and male participants were divided into four groups. Quartile 4 (Men: 5.67±0.35, Women: 4.70±0.32 Kg/m2) and quartile 1 (Men: 7.60±0.29, Women: 6.56±0.53 Kg/m2) represented low muscle mass and control groups, respectively. After multivariable adjustment, except for physical function, we found that blood urea nitrogen, creatinine, and age were associated with ASMI in men. However, only triglyceride level was related to ASMI in women. The multiple logistic regression models were used to analyze in each baseline characteristic and metabolite concentration. After the adjustment, we identify amino acid-related metabolites and show that glutamate levels in women and alpha-aminoadipate, Dopa, and citrulline/ornithine levels in men are gender-specific metabolic signatures of muscle mass loss.
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Affiliation(s)
- Chi-Jen Lo
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan
| | - Yu-Shien Ko
- Division of Cardiology, Chang Gung Memorial Hospital, Taipei 105, Taiwan.,College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - Su-Wei Chang
- Clinical Informatics and Medical Statistics Research Center, Chang Gung University, Taoyuan 333, Taiwan
| | - Hsiang-Yu Tang
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan
| | - Cheng-Yu Huang
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan
| | - Yu-Chen Huang
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan.,Department of Thoracic Medicine, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Hung-Yao Ho
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan.,Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan.,Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Chih-Ming Lin
- College of Medicine, Chang Gung University, Taoyuan 333, Taiwan.,Division of Internal Medicine, Chang Gung Memorial Hospital, Taipei 105, Taiwan.,Department of Health Management, Chang Gung Health and Culture Village, Taoyuan 333, Taiwan
| | - Mei-Ling Cheng
- Metabolomics Core Laboratory, Healthy Aging Research Center, Chang Gung University, Taoyuan 333, Taiwan.,Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan.,Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
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35
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Rossetti ML, Tomko RJ, Gordon BS. Androgen depletion alters the diurnal patterns to signals that regulate autophagy in the limb skeletal muscle. Mol Cell Biochem 2020; 476:959-969. [PMID: 33128669 DOI: 10.1007/s11010-020-03963-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/23/2020] [Indexed: 12/14/2022]
Abstract
Hypogonadism contributes to limb skeletal muscle atrophy by increasing rates of muscle protein breakdown. Androgen depletion increases markers of the autophagy protein breakdown pathway in the limb muscle that persist throughout the diurnal cycle. However, the regulatory signals underpinning the increase in autophagy markers remain ill-defined. The purpose of this study was to characterize changes to autophagy regulatory signals in the limb skeletal muscle following androgen depletion. Male mice were subjected to a castration surgery or a sham surgery as a control. Seven weeks post-surgery, a subset of mice from each group was sacrificed every 4 hr over a 24 hr period. Protein and mRNA from the Tibialis Anterior (TA) were subjected to Western blot and RT-PCR. Consistent with an overall increase in autophagy, the phosphorylation pattern of Uncoordinated Like Kinase 1 (ULK1) (Ser555) was elevated throughout the diurnal cycle in the TA of castrated mice. Factors that induce the progression of autophagy were also increased in the TA following androgen depletion including an increase in the phosphorylation of c-Jun N-terminal Kinase (JNK) (Thr183/Tyr185) and an increase in the ratio of BCL-2 Associated X (BAX) to B-cell lymphoma 2 (BCL-2). Moreover, we observed an increase in the protein expression pattern of p53 and the mRNA of the p53 target genes Cyclin-Dependent Kinase Inhibitor 1A (p21) and Growth Arrest and DNA Damage Alpha (Gadd45a), which are known to increase autophagy and induce muscle atrophy. These data characterize novel changes to autophagy regulatory signals in the limb skeletal muscle following androgen deprivation.
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Affiliation(s)
- Michael L Rossetti
- Department of Nutrition, Food and Exercise Science, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA
| | - Robert J Tomko
- Department of Biomedical Sciences, Florida State University College of Medicine, 115 W Call Street, Tallahassee, FL, 32304, USA
| | - Bradley S Gordon
- Department of Nutrition, Food and Exercise Science, Florida State University, 600 W. Cottage Avenue, Tallahassee, FL, 32306, USA.
- Institute of Sports Sciences and Medicine, Florida State University, 600 W. Cottage Ave, Tallahassee, FL, 32306, USA.
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36
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Romanello V, Sandri M. The connection between the dynamic remodeling of the mitochondrial network and the regulation of muscle mass. Cell Mol Life Sci 2020; 78:1305-1328. [PMID: 33078210 PMCID: PMC7904552 DOI: 10.1007/s00018-020-03662-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/02/2020] [Accepted: 09/28/2020] [Indexed: 12/11/2022]
Abstract
The dynamic coordination of processes controlling the quality of the mitochondrial network is crucial to maintain the function of mitochondria in skeletal muscle. Changes of mitochondrial proteolytic system, dynamics (fusion/fission), and mitophagy induce pathways that affect muscle mass and performance. When muscle mass is lost, the risk of disease onset and premature death is dramatically increased. For instance, poor quality of muscles correlates with the onset progression of several age-related disorders such as diabetes, obesity, cancer, and aging sarcopenia. To date, there are no drug therapies to reverse muscle loss, and exercise remains the best approach to improve mitochondrial health and to slow atrophy in several diseases. This review will describe the principal mechanisms that control mitochondrial quality and the pathways that link mitochondrial dysfunction to muscle mass regulation.
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Affiliation(s)
- Vanina Romanello
- Venetian Institute of Molecular Medicine, via Orus 2, 35129, Padova, Italy.
- Department of Biomedical Science, University of Padova, via G. Colombo 3, 35100, Padova, Italy.
| | - Marco Sandri
- Venetian Institute of Molecular Medicine, via Orus 2, 35129, Padova, Italy.
- Department of Biomedical Science, University of Padova, via G. Colombo 3, 35100, Padova, Italy.
- Department of Medicine, McGill University, Montreal, Canada.
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Vainshtein A, Sandri M. Signaling Pathways That Control Muscle Mass. Int J Mol Sci 2020; 21:ijms21134759. [PMID: 32635462 PMCID: PMC7369702 DOI: 10.3390/ijms21134759] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/23/2020] [Accepted: 07/01/2020] [Indexed: 12/12/2022] Open
Abstract
The loss of skeletal muscle mass under a wide range of acute and chronic maladies is associated with poor prognosis, reduced quality of life, and increased mortality. Decades of research indicate the importance of skeletal muscle for whole body metabolism, glucose homeostasis, as well as overall health and wellbeing. This tissue’s remarkable ability to rapidly and effectively adapt to changing environmental cues is a double-edged sword. Physiological adaptations that are beneficial throughout life become maladaptive during atrophic conditions. The atrophic program can be activated by mechanical, oxidative, and energetic distress, and is influenced by the availability of nutrients, growth factors, and cytokines. Largely governed by a transcription-dependent mechanism, this program impinges on multiple protein networks including various organelles as well as biosynthetic and quality control systems. Although modulating muscle function to prevent and treat disease is an enticing concept that has intrigued research teams for decades, a lack of thorough understanding of the molecular mechanisms and signaling pathways that control muscle mass, in addition to poor transferability of findings from rodents to humans, has obstructed efforts to develop effective treatments. Here, we review the progress made in unraveling the molecular mechanisms responsible for the regulation of muscle mass, as this continues to be an intensive area of research.
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Affiliation(s)
| | - Marco Sandri
- Veneto Institute of Molecular Medicine, via Orus 2, 35129 Padua, Italy
- Department of Biomedical Science, University of Padua, via G. Colombo 3, 35100 Padua, Italy
- Myology Center, University of Padua, via G. Colombo 3, 35100 Padova, Italy
- Department of Medicine, McGill University, Montreal, QC H3A 0G4, Canada
- Correspondence:
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Brown LA, Guzman SD, Brooks SV. Emerging molecular mediators and targets for age-related skeletal muscle atrophy. Transl Res 2020; 221:44-57. [PMID: 32243876 PMCID: PMC8026108 DOI: 10.1016/j.trsl.2020.03.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 12/20/2022]
Abstract
The age-associated decline in muscle mass has become synonymous with physical frailty among the elderly due to its major contribution in reduced muscle function. Alterations in protein and redox homeostasis along with chronic inflammation, denervation, and hormonal dysregulation are all hallmarks of muscle wasting and lead to clinical sarcopenia in older adults. Reduction in skeletal muscle mass has been observed and reported in the scientific literature for nearly 2 centuries; however, identification and careful examination of molecular mediators of age-related muscle atrophy have only been possible for roughly 3 decades. Here we review molecular targets of recent interest in age-related muscle atrophy and briefly discuss emerging small molecule therapeutic treatments for muscle wasting in sarcopenic susceptible populations.
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Affiliation(s)
- Lemuel A Brown
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Steve D Guzman
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Susan V Brooks
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan; Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan.
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Korponay TC, Balnis J, Vincent CE, Singer DV, Chopra A, Adam AP, Ginnan R, Singer HA, Jaitovich A. High CO 2 Downregulates Skeletal Muscle Protein Anabolism via AMP-activated Protein Kinase α2-mediated Depressed Ribosomal Biogenesis. Am J Respir Cell Mol Biol 2020; 62:74-86. [PMID: 31264907 DOI: 10.1165/rcmb.2019-0061oc] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
High CO2 retention, or hypercapnia, is associated with worse outcomes in patients with chronic pulmonary diseases. Skeletal muscle wasting is also an independent predictor of poor outcomes in patients with acute and chronic pulmonary diseases. Although previous evidence indicates that high CO2 accelerates skeletal muscle catabolism via AMPK (AMP-activated protein kinase)-FoxO3a-MuRF1 (E3-ubiquitin ligase muscle RING finger protein 1), little is known about the role of high CO2 in regulating skeletal muscle anabolism. In the present study, we investigated the potential role of high CO2 in attenuating skeletal muscle protein synthesis. We found that locomotor muscles from patients with chronic CO2 retention demonstrated depressed ribosomal gene expression in comparison with locomotor muscles from non-CO2-retaining individuals, and analysis of the muscle proteome of normo- and hypercapnic mice indicates reduction of important components of ribosomal structure and function. Indeed, mice chronically kept under a high-CO2 environment show evidence of skeletal muscle downregulation of ribosomal biogenesis and decreased protein synthesis as measured by the incorporation of puromycin into skeletal muscle. Hypercapnia did not regulate the mTOR pathway, and rapamycin-induced deactivation of mTOR did not cause a decrease in ribosomal gene expression. Loss-of-function studies in cultured myotubes showed that AMPKα2 regulates CO2-mediated reductions in ribosomal gene expression and protein synthesis. Although previous evidence has implicated TIF1A (transcription initiation factor-1α) and KDM2A (lysine-specific demethylase 2A) in AMPK-driven regulation of ribosomal gene expression, we found that these mediators were not required in the high CO2-induced depressed protein anabolism. Our research supports future studies targeting ribosomal biogenesis and protein synthesis to alleviate the effects of high CO2 on skeletal muscle turnover.
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Affiliation(s)
- Tanner C Korponay
- Division of Pulmonary and Critical Care Medicine.,Department of Molecular and Cellular Physiology, and
| | - Joseph Balnis
- Division of Pulmonary and Critical Care Medicine.,Department of Molecular and Cellular Physiology, and
| | | | | | - Amit Chopra
- Division of Pulmonary and Critical Care Medicine
| | - Alejandro P Adam
- Department of Molecular and Cellular Physiology, and.,Department of Ophthalmology, Albany Medical College, Albany, New York; and
| | - Roman Ginnan
- Department of Molecular and Cellular Physiology, and
| | | | - Ariel Jaitovich
- Division of Pulmonary and Critical Care Medicine.,Department of Molecular and Cellular Physiology, and
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40
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Rasmussen BB, Adams CM. ATF4 Is a Fundamental Regulator of Nutrient Sensing and Protein Turnover. J Nutr 2020; 150:979-980. [PMID: 32190894 PMCID: PMC7198309 DOI: 10.1093/jn/nxaa067] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 02/12/2020] [Accepted: 02/25/2020] [Indexed: 01/11/2023] Open
Affiliation(s)
- Blake B Rasmussen
- Department of Nutrition & Metabolism, University of Texas Medical Branch at Galveston, Galveston, TX, USA,Address correspondence to BBR (e-mail: )
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Hentilä J, Hulmi JJ, Laakkonen EK, Ahtiainen JP, Suominen H, Korhonen MT. Sprint and Strength Training Modulates Autophagy and Proteostasis in Aging Sprinters. Med Sci Sports Exerc 2020; 52:1948-1959. [PMID: 32205677 DOI: 10.1249/mss.0000000000002340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Exercise and aging may modulate muscle protein homeostasis and autophagy, but few studies examine highly trained middle-age or older individuals. This study elucidated the effects of a new long-term training stimulus on markers of muscle autophagy and unfolded protein response (UPR) and on sprint running performance in masters sprinters. METHODS Thirty-two male competitive sprinters (age 40-76 yr) were randomly divided into experimental (EX) and control (CTRL) groups. The EX training program was a combination of heavy and explosive strength and sprint exercises aimed at improving sprint performance. Fifteen and thirteen participants completed the 20-wk intervention period in EX and CTRL, respectively. The latter were told to continue their routine exercises. Key protein markers were analyzed by Western blotting from vastus lateralis (VL) muscle biopsies. The muscle thickness of VL was analyzed by ultrasonography and sprint performance by a 60-m running test. RESULTS EX induced improvement in 60-m sprint performance when compared with controls (time-group, P = 0.003) without changes in VL muscle thickness. Content of lipidated microtubule-associated protein 1A/1B-light chain 3 (LC3-II) increased in EX (P = 0.022), suggesting increased autophagosome content. In addition, an autophagosome clearance marker sequestosome 1 (p62) decreased in EX (P = 0.006). Markers of UPR selectively modulated with decreases (e.g., ATF4, P = 0.003) and increases (e.g., EIF2α, P = 0.019) observed in EX. CONCLUSIONS These findings suggest that a new intensive training stimulus that combines strength training with sprint training may increase muscle autophagosome content in a basal state without any evidence of impaired autophagosome clearance in masters sprinters. Simultaneously, the combined training may have a selective effect on the content of UPR signaling components.
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Affiliation(s)
- Jaakko Hentilä
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, FINLAND
| | | | - Eija K Laakkonen
- Faculty of Sport and Health Sciences, Gerontology Research Center, University of Jyväskylä, Jyväskylä, FINLAND
| | - Juha P Ahtiainen
- Faculty of Sport and Health Sciences, Neuromuscular Research Center, University of Jyväskylä, Jyväskylä, FINLAND
| | - Harri Suominen
- Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, FINLAND
| | - Marko T Korhonen
- Faculty of Sport and Health Sciences, Gerontology Research Center, University of Jyväskylä, Jyväskylä, FINLAND
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42
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Doerr V, Montalvo RN, Kwon OS, Talbert EE, Hain BA, Houston FE, Smuder AJ. Prevention of Doxorubicin-Induced Autophagy Attenuates Oxidative Stress and Skeletal Muscle Dysfunction. Antioxidants (Basel) 2020; 9:antiox9030263. [PMID: 32210013 PMCID: PMC7139604 DOI: 10.3390/antiox9030263] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/16/2020] [Accepted: 03/20/2020] [Indexed: 12/31/2022] Open
Abstract
Clinical use of the chemotherapeutic doxorubicin (DOX) promotes skeletal muscle atrophy and weakness, adversely affecting patient mobility and strength. Although the mechanisms responsible for DOX-induced skeletal muscle dysfunction remain unclear, studies implicate the significant production of reactive oxygen species (ROS) in this pathology. Supraphysiological ROS levels can enhance protein degradation via autophagy, and it is established that DOX upregulates autophagic signaling in skeletal muscle. To determine the precise contribution of accelerated autophagy to DOX-induced skeletal muscle dysfunction, we inhibited autophagy in the soleus via transduction of a dominant negative mutation of the autophagy related 5 (ATG5) protein. Targeted inhibition of autophagy prevented soleus muscle atrophy and contractile dysfunction acutely following DOX administration, which was associated with a reduction in mitochondrial ROS and maintenance of mitochondrial respiratory capacity. These beneficial modifications were potentially the result of enhanced transcription of antioxidant response element-related genes and increased antioxidant capacity. Specifically, our results showed significant upregulation of peroxisome proliferator-activated receptor gamma co-activator 1-alpha, nuclear respiratory factor-1, nuclear factor erythroid-2-related factor-2, nicotinamide-adenine dinucleotide phosphate quinone dehydrogenase-1, and catalase in the soleus with DOX treatment when autophagy was inhibited. These findings establish a significant role of autophagy in the development of oxidative stress and skeletal muscle weakness following DOX administration.
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Affiliation(s)
- Vivian Doerr
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (V.D.); (R.N.M.)
| | - Ryan N. Montalvo
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (V.D.); (R.N.M.)
| | - Oh Sung Kwon
- Department of Kinesiology, University of Connecticut, Storrs, CT 06269, USA;
| | - Erin E. Talbert
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA 52242, USA;
| | - Brian A. Hain
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA 17033, USA;
| | - Fraser E. Houston
- Department of Health Sciences and Human Performance, University of Tampa, Tampa, FL 33606, USA;
| | - Ashley J. Smuder
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (V.D.); (R.N.M.)
- Correspondence:
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43
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You W, Xu Z, Shan T. Regulatory Roles of GADD45α in Skeletal Muscle and Adipocyte. Curr Protein Pept Sci 2020; 20:918-925. [PMID: 31232235 DOI: 10.2174/1389203720666190624143503] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 06/02/2019] [Accepted: 06/11/2019] [Indexed: 02/07/2023]
Abstract
GADD45α, a member of the GADD45 family proteins, is involved in various cellular processes including the maintenance of genomic integrity, growth arrest, apoptosis, senescence, and signal transduction. In skeletal muscle, GADD45α plays an important role in regulating mitochondrial biogenesis and muscle atrophy. In adipocytes, GADD45α regulates preadipocyte differentiation, lipid accumulation, and thermogenesis metabolism. Moreover, it has been recently demonstrated that GADD45α promotes gene activation by inducing DNA demethylation. The epigenetic function of GADD45α is important for preadipocyte differentiation and transcriptional regulation during development. This article mainly reviews and discusses the regulatory roles of GADD45α in skeletal muscle development, adipocyte progenitor differentiation, and DNA demethylation.
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Affiliation(s)
- Wenjing You
- College of Animal Sciences, Zhejiang University; The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang Provincial Laboratory of Feed and Animal Nutrition, No. 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, China
| | - Ziye Xu
- College of Animal Sciences, Zhejiang University; The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang Provincial Laboratory of Feed and Animal Nutrition, No. 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, China
| | - Tizhong Shan
- College of Animal Sciences, Zhejiang University; The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang Provincial Laboratory of Feed and Animal Nutrition, No. 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, China
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Ebert SM, Al-Zougbi A, Bodine SC, Adams CM. Skeletal Muscle Atrophy: Discovery of Mechanisms and Potential Therapies. Physiology (Bethesda) 2020; 34:232-239. [PMID: 31165685 DOI: 10.1152/physiol.00003.2019] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Skeletal muscle atrophy proceeds through a complex molecular signaling network that is just beginning to be understood. Here, we discuss examples of recently identified molecular mechanisms of muscle atrophy and how they highlight an immense need and opportunity for focused biochemical investigations and further unbiased discovery work.
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Affiliation(s)
- Scott M Ebert
- Departments of Internal Medicine and Molecular Physiology and Biophysics, and the Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa , Iowa City, Iowa.,Emmyon, Inc., Coralville, Iowa
| | - Asma Al-Zougbi
- Departments of Internal Medicine and Molecular Physiology and Biophysics, and the Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa , Iowa City, Iowa
| | - Sue C Bodine
- Departments of Internal Medicine and Molecular Physiology and Biophysics, and the Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa , Iowa City, Iowa.,Emmyon, Inc., Coralville, Iowa
| | - Christopher M Adams
- Departments of Internal Medicine and Molecular Physiology and Biophysics, and the Fraternal Order of Eagles Diabetes Research Center, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa , Iowa City, Iowa.,Emmyon, Inc., Coralville, Iowa.,Iowa City Veterans Affairs Medical Center, Iowa City, Iowa
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45
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Ebert SM, Bullard SA, Basisty N, Marcotte GR, Skopec ZP, Dierdorff JM, Al-Zougbi A, Tomcheck KC, DeLau AD, Rathmacher JA, Bodine SC, Schilling B, Adams CM. Activating transcription factor 4 (ATF4) promotes skeletal muscle atrophy by forming a heterodimer with the transcriptional regulator C/EBPβ. J Biol Chem 2020; 295:2787-2803. [PMID: 31953319 PMCID: PMC7049960 DOI: 10.1074/jbc.ra119.012095] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/10/2020] [Indexed: 12/17/2022] Open
Abstract
Skeletal muscle atrophy is a highly-prevalent and debilitating condition that remains poorly understood at the molecular level. Previous work found that aging, fasting, and immobilization promote skeletal muscle atrophy via expression of activating transcription factor 4 (ATF4) in skeletal muscle fibers. However, the direct biochemical mechanism by which ATF4 promotes muscle atrophy is unknown. ATF4 is a member of the basic leucine zipper transcription factor (bZIP) superfamily. Because bZIP transcription factors are obligate dimers, and because ATF4 is unable to form highly-stable homodimers, we hypothesized that ATF4 may promote muscle atrophy by forming a heterodimer with another bZIP family member. To test this hypothesis, we biochemically isolated skeletal muscle proteins that associate with the dimerization- and DNA-binding domain of ATF4 (the bZIP domain) in mouse skeletal muscle fibers in vivo Interestingly, we found that ATF4 forms at least five distinct heterodimeric bZIP transcription factors in skeletal muscle fibers. Furthermore, one of these heterodimers, composed of ATF4 and CCAAT enhancer-binding protein β (C/EBPβ), mediates muscle atrophy. Within skeletal muscle fibers, the ATF4-C/EBPβ heterodimer interacts with a previously unrecognized and evolutionarily conserved ATF-C/EBP composite site in exon 4 of the Gadd45a gene. This three-way interaction between ATF4, C/EBPβ, and the ATF-C/EBP composite site activates the Gadd45a gene, which encodes a critical mediator of muscle atrophy. Together, these results identify a biochemical mechanism by which ATF4 induces skeletal muscle atrophy, providing molecular-level insights into the etiology of skeletal muscle atrophy.
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Affiliation(s)
- Scott M Ebert
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246; Emmyon, Inc., Coralville, Iowa 52241
| | - Steven A Bullard
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Nathan Basisty
- Buck Institute for Research on Aging, Novato, California 94945
| | - George R Marcotte
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Zachary P Skopec
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Jason M Dierdorff
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Asma Al-Zougbi
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Kristin C Tomcheck
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Austin D DeLau
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Jacob A Rathmacher
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246
| | - Sue C Bodine
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Emmyon, Inc., Coralville, Iowa 52241
| | | | - Christopher M Adams
- Departments of Internal Medicine and Molecular Physiology and Biophysics, Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa 52242; Iowa City Veterans Affairs Medical Center, Iowa City, Iowa 52246; Emmyon, Inc., Coralville, Iowa 52241.
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46
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Kelahmetoglu Y, Jannig PR, Cervenka I, Koch LG, Britton SL, Zhou J, Wang H, Robinson MM, Nair KS, Ruas JL. Comparative Analysis of Skeletal Muscle Transcriptional Signatures Associated With Aerobic Exercise Capacity or Response to Training in Humans and Rats. Front Endocrinol (Lausanne) 2020; 11:591476. [PMID: 33193103 PMCID: PMC7649134 DOI: 10.3389/fendo.2020.591476] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 09/28/2020] [Indexed: 11/16/2022] Open
Abstract
Increasing exercise capacity promotes healthy aging and is strongly associated with lower mortality rates. In this study, we analyzed skeletal muscle transcriptomics coupled to exercise performance in humans and rats to dissect the inherent and response components of aerobic exercise capacity. Using rat models selected for intrinsic and acquired aerobic capacity, we determined that the high aerobic capacity muscle transcriptome is associated with pathways for tissue oxygenation and vascularization. Conversely, the low capacity muscle transcriptome indicated immune response and metabolic dysfunction. Low response to training was associated with an inflammatory signature and revealed a potential link to circadian rhythm. Next, we applied bioinformatics tools to predict potential secreted factors (myokines). The predicted secretome profile for exercise capacity highlighted circulatory factors involved in lipid metabolism and the exercise response secretome was associated with extracellular matrix remodelling. Lastly, we utilized human muscle mitochondrial respiration and transcriptomics data to explore molecular mediators of exercise capacity and response across species. Human transcriptome comparison highlighted epigenetic mechanisms linked to exercise capacity and the damage repair for response. Overall, our findings from this cross-species transcriptome analysis of exercise capacity and response establish a foundation for future studies on the mechanisms that link exercise and health.
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Affiliation(s)
- Yildiz Kelahmetoglu
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska Institute, Stockholm, Sweden
| | - Paulo R. Jannig
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska Institute, Stockholm, Sweden
| | - Igor Cervenka
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska Institute, Stockholm, Sweden
| | - Lauren G. Koch
- Department of Physiology and Pharmacology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
| | - Steven L. Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - Jiajia Zhou
- Li Ka Shing Institute of Health Sciences, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Huating Wang
- Li Ka Shing Institute of Health Sciences, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, China
| | - Matthew M. Robinson
- School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States
- Department of Integrative Physiology, Division of Endocrinology, Diabetes and Nutrition, Mayo Clinic, Rochester, MN, United States
| | - K Sreekumaran Nair
- Department of Integrative Physiology, Division of Endocrinology, Diabetes and Nutrition, Mayo Clinic, Rochester, MN, United States
| | - Jorge L. Ruas
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska Institute, Stockholm, Sweden
- *Correspondence: Jorge L. Ruas,
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Roy A, Kumar A. ER Stress and Unfolded Protein Response in Cancer Cachexia. Cancers (Basel) 2019; 11:cancers11121929. [PMID: 31817027 PMCID: PMC6966641 DOI: 10.3390/cancers11121929] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 11/26/2019] [Accepted: 11/30/2019] [Indexed: 12/13/2022] Open
Abstract
Cancer cachexia is a devastating syndrome characterized by unintentional weight loss attributed to extensive skeletal muscle wasting. The pathogenesis of cachexia is multifactorial because of complex interactions of tumor and host factors. The irreversible wasting syndrome has been ascribed to systemic inflammation, insulin resistance, dysfunctional mitochondria, oxidative stress, and heightened activation of ubiquitin-proteasome system and macroautophagy. Accumulating evidence suggests that deviant regulation of an array of signaling pathways engenders cancer cachexia where the human body is sustained in an incessant self-consuming catabolic state. Recent studies have further suggested that several components of endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) are activated in skeletal muscle of animal models and muscle biopsies of cachectic cancer patients. However, the exact role of ER stress and the individual arms of the UPR in the regulation of skeletal muscle mass in various catabolic states including cancer has just begun to be elucidated. This review provides a succinct overview of emerging roles of ER stress and the UPR in cancer-induced skeletal muscle wasting.
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Hughes DC, Marcotte GR, Baehr LM, West DWD, Marshall AG, Ebert SM, Davidyan A, Adams CM, Bodine SC, Baar K. Alterations in the muscle force transfer apparatus in aged rats during unloading and reloading: impact of microRNA-31. J Physiol 2019; 596:2883-2900. [PMID: 29726007 DOI: 10.1113/jp275833] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/16/2018] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS Force transfer is integral for maintaining skeletal muscle structure and function. One important component is dystrophin. There is limited understanding of how force transfer is impacted by age and loading. Here, we investigate the force transfer apparatus in muscles of adult and old rats exposed to periods of disuse and reloading. Our results demonstrate an increase in dystrophin protein during the reloading phase in the adult tibialis anterior muscle that is delayed in the old muscle. The consequence of this delay is an increased susceptibility towards contraction-induced muscle injury. Central to the lack of dystrophin protein is an increase in miR-31, a microRNA that inhibits dystrophin translation. In vivo electroporation with a miR-31 sponge led to increased dystrophin protein and decreased contraction-induced muscle injury in old skeletal muscle. Overall, our results detail the importance of the force transfer apparatus and provide new mechanisms for contraction-induced injury in ageing skeletal muscle. ABSTRACT In healthy muscle, the dystrophin-associated glycoprotein complex (DGC), the integrin/focal adhesion complex, intermediate filaments and Z-line proteins transmit force from the contractile proteins to the extracellular matrix. How loading and age affect these proteins is poorly understood. The experiments reported here sought to determine the effect of ageing on the force transfer apparatus following muscle unloading and reloading. Adult (9 months) and old (28 months) rats were subjected to 14 days of hindlimb unloading and 1, 3, 7 and 14 days of reloading. The DGC complex, intermediate filament and Z-line protein and mRNA levels, as well as dystrophin-targeting miRNAs (miR-31, -146b and -374) were examined in the tibialis anterior (TA) and medial gastrocnemius muscles at both ages. There was a significant increase in dystrophin protein levels (2.79-fold) upon 3 days of reloading in the adult TA muscle that did not occur in the old rats (P ≤ 0.05), and the rise in dystrophin protein occurred independent of dystrophin mRNA. The disconnect between dystrophin protein and mRNA levels can partially be explained by age-dependent differences in miR-31. The impaired dystrophin response in aged muscle was followed by an increase in other force transfer proteins (β-dystroglycan, desmuslin and LIM) that was not sufficient to prevent membrane disruption and muscle injury early in the reloading period. Inserting a miR-31 sponge increased dystrophin protein and decreased contraction-induced injury in the TA (P ≤ 0.05). Collectively, these data suggest that increased miR-31 with age contributes to an impaired dystrophin response and increased muscle injury after disuse.
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Affiliation(s)
- David C Hughes
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA, USA
| | - George R Marcotte
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA, USA
| | - Leslie M Baehr
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA.,VA Northern California Health Care System, Mather, CA, USA
| | - Daniel W D West
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA.,VA Northern California Health Care System, Mather, CA, USA
| | - Andrea G Marshall
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA, USA.,Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA
| | - Scott M Ebert
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA, USA.,Iowa City Veterans Affairs Medical Center, Iowa City, IA, USA
| | - Arik Davidyan
- Molecular, Cellular, and Integrative Physiology Graduate Group, University of California Davis, Davis, CA, USA
| | - Christopher M Adams
- Department of Internal Medicine, University of Iowa, Iowa City, IA, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA, USA.,Iowa City Veterans Affairs Medical Center, Iowa City, IA, USA
| | - Sue C Bodine
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA, USA.,Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA.,VA Northern California Health Care System, Mather, CA, USA
| | - Keith Baar
- Department of Neurobiology, Physiology and Behavior, University of California Davis, Davis, CA, USA.,Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, USA.,VA Northern California Health Care System, Mather, CA, USA
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Ebert SM, Dierdorff JM, Meyerholz DK, Bullard SA, Al-Zougbi A, DeLau AD, Tomcheck KC, Skopec ZP, Marcotte GR, Bodine SC, Adams CM. An investigation of p53 in skeletal muscle aging. J Appl Physiol (1985) 2019; 127:1075-1084. [PMID: 31465716 PMCID: PMC6850986 DOI: 10.1152/japplphysiol.00363.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/06/2019] [Accepted: 08/22/2019] [Indexed: 11/22/2022] Open
Abstract
Age-related skeletal muscle atrophy is a very common and serious condition that remains poorly understood at the molecular level. Several lines of evidence have suggested that the tumor suppressor p53 may play a central, causative role in skeletal muscle aging, whereas other, apparently contradictory lines of evidence have suggested that p53 may be critical for normal skeletal muscle function. To help address these issues, we performed an aging study in male muscle-specific p53-knockout mice (p53 mKO mice), which have a lifelong absence of p53 expression in skeletal muscle fibers. We found that the absence of p53 expression in skeletal muscle fibers had no apparent deleterious or beneficial effects on skeletal muscle mass or function under basal conditions up to 6 mo of age, when mice are fully grown and exhibit peak muscle mass and function. Furthermore, at 22 and 25 mo of age, when age-related muscle weakness and atrophy are clearly evident in mice, p53 mKO mice demonstrated no improvement or worsening of skeletal muscle mass or function relative to littermate control mice. At advanced ages, p53 mKO mice began to die prematurely and had an increased incidence of osteosarcoma, precluding analyses of muscle mass and function in very old p53 mKO mice. In light of these results, we conclude that p53 expression in skeletal muscle fibers has minimal if any direct, cell autonomous effect on basal or age-related changes in skeletal muscle mass and function up to at least 22 mo of age.NEW & NOTEWORTHY Previous studies implicated the transcriptional regulator p53 as a potential mediator of age-related skeletal muscle weakness and atrophy. We tested this hypothesis by investigating the effect of aging in muscle-specific p53-knockout mice. Our results strongly suggest that p53 activity within skeletal muscle fibers is not required for age-related skeletal muscle atrophy or weakness.
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Affiliation(s)
- Scott M Ebert
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
- Emmyon, Inc., Coralville, Iowa
| | - Jason M Dierdorff
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | | | - Steven A Bullard
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Asma Al-Zougbi
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Austin D DeLau
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Kristin C Tomcheck
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Zachary P Skopec
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - George R Marcotte
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
| | - Sue C Bodine
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
- Emmyon, Inc., Coralville, Iowa
| | - Christopher M Adams
- Departments of Internal Medicine and Molecular Physiology and Biophysics and Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa
- Emmyon, Inc., Coralville, Iowa
- Iowa City Department of Veterans Affairs Medical Center, Iowa City, Iowa
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50
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Inhibition of the Fission Machinery Mitigates OPA1 Impairment in Adult Skeletal Muscles. Cells 2019; 8:cells8060597. [PMID: 31208084 PMCID: PMC6627087 DOI: 10.3390/cells8060597] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/29/2019] [Accepted: 06/07/2019] [Indexed: 12/16/2022] Open
Abstract
The maintenance of muscle mass and its ability to function relies on a bioenergetic efficient mitochondrial network. This network is highly impacted by fusion and fission events. We have recently shown that the acute deletion of the fusion protein Opa1 induces muscle atrophy, systemic inflammatory response, precocious epithelial senescence, and premature death that are caused by muscle-dependent secretion of FGF21. However, both fusion and fission machinery are suppressed in aging sarcopenia, cancer cachexia, and chemotherapy-induced muscle wasting. We generated inducible muscle-specific Opa1 and Drp1 double-knockout mice to address the physiological relevance of the concomitant impairment of fusion and fission machinery in skeletal muscle. Here we show that acute ablation of Opa1 and Drp1 in adult muscle causes the accumulation of abnormal and dysfunctional mitochondria, as well as the inhibition of autophagy and mitophagy pathways. This ultimately results in ER stress, muscle loss, and the reduction of force generation. However, the simultaneous inhibition of the fission protein Drp1 when Opa1 is absent alleviates FGF21 induction, oxidative stress, denervation, and inflammation rescuing the lethal phenotype of Opa1 knockout mice, despite the presence of any muscle weakness. Thus, the simultaneous inhibition of fusion and fission processes mitigates the detrimental effects of unbalanced mitochondrial fusion and prevents the secretion of pro-senescence factors.
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