1
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Elgaabari A, Imatomi N, Kido H, Nakashima T, Okuda S, Manabe Y, Sawano S, Mizunoya W, Kaneko R, Tanaka S, Maeno T, Matsuyoshi Y, Seki M, Kuwakado S, Zushi K, Daneshvar N, Nakamura M, Suzuki T, Sunagawa K, Anderson JE, Allen RE, Tatsumi R. Age-related nitration/dysfunction of myogenic stem cell activator HGF. Aging Cell 2024; 23:e14041. [PMID: 37985931 PMCID: PMC10861216 DOI: 10.1111/acel.14041] [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: 05/27/2023] [Revised: 10/27/2023] [Accepted: 10/28/2023] [Indexed: 11/22/2023] Open
Abstract
Mechanical perturbation triggers activation of resident myogenic stem cells to enter the cell cycle through a cascade of events including hepatocyte growth factor (HGF) release from its extracellular tethering and the subsequent presentation to signaling-receptor c-met. Here, we show that with aging, extracellular HGF undergoes tyrosine-residue (Y) nitration and loses c-met binding, thereby disturbing muscle homeostasis. Biochemical studies demonstrated that nitration/dysfunction is specific to HGF among other major growth factors and is characterized by its locations at Y198 and Y250 in c-met-binding domains. Direct-immunofluorescence microscopy of lower hind limb muscles from three age groups of rat, provided direct in vivo evidence for age-related increases in nitration of ECM-bound HGF, preferentially stained for anti-nitrated Y198 and Y250-HGF mAbs (raised in-house) in fast IIa and IIx myofibers. Overall, findings highlight inhibitory impacts of HGF nitration on myogenic stem cell dynamics, pioneering a cogent discussion for better understanding age-related muscle atrophy and impaired regeneration with fibrosis (including sarcopenia and frailty).
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Affiliation(s)
- Alaa Elgaabari
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
- Department of Physiology, Faculty of Veterinary MedicineKafrelsheikh UniversityKafrelsheikhEgypt
| | - Nana Imatomi
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Hirochika Kido
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Takashi Nakashima
- Department of Bioscience and Biotechnology, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Shoko Okuda
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Yoshitaka Manabe
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Shoko Sawano
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
- Present address:
Department of Food and Life Science, School of Life and Environmental ScienceAzabu UniversitySagamiharaJapan
| | - Wataru Mizunoya
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
- Present address:
Department of Animal Science and Biotechnology, School of Veterinary MedicineAzabu UniversitySagamiharaJapan
| | - Ryuki Kaneko
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Sakiho Tanaka
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Takahiro Maeno
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Yuji Matsuyoshi
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Miyumi Seki
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - So Kuwakado
- Department of Orthopaedic Surgery, Faculty of Medical SciencesKyushu UniversityFukuokaJapan
| | - Kahona Zushi
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Nasibeh Daneshvar
- Department of Biological Sciences, Faculty of ScienceUniversity of ManitobaWinnipegManitobaCanada
| | - Mako Nakamura
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Takahiro Suzuki
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
| | - Kenji Sunagawa
- Department of Cardiovascular Medicine, Graduate School of MedicineKyushu UniversityFukuokaJapan
| | - Judy E. Anderson
- Department of Biological Sciences, Faculty of ScienceUniversity of ManitobaWinnipegManitobaCanada
| | - Ronald E. Allen
- The School of Animal and Comparative Biomedical SciencesUniversity of ArizonaTucsonArizonaUSA
| | - Ryuichi Tatsumi
- Department of Animal and Marine Bioresource Sciences, Graduate School of AgricultureKyushu UniversityFukuokaJapan
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2
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Broadway-Stringer S, Jiang H, Wadmore K, Hooper C, Douglas G, Steeples V, Azad AJ, Singer E, Reyat JS, Galatik F, Ehler E, Bennett P, Kalisch-Smith JI, Sparrow DB, Davies B, Djinovic-Carugo K, Gautel M, Watkins H, Gehmlich K. Insights into the Role of a Cardiomyopathy-Causing Genetic Variant in ACTN2. Cells 2023; 12:721. [PMID: 36899856 PMCID: PMC10001372 DOI: 10.3390/cells12050721] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 02/13/2023] [Accepted: 02/21/2023] [Indexed: 03/12/2023] Open
Abstract
Pathogenic variants in ACTN2, coding for alpha-actinin 2, are known to be rare causes of Hypertrophic Cardiomyopathy. However, little is known about the underlying disease mechanisms. Adult heterozygous mice carrying the Actn2 p.Met228Thr variant were phenotyped by echocardiography. For homozygous mice, viable E15.5 embryonic hearts were analysed by High Resolution Episcopic Microscopy and wholemount staining, complemented by unbiased proteomics, qPCR and Western blotting. Heterozygous Actn2 p.Met228Thr mice have no overt phenotype. Only mature males show molecular parameters indicative of cardiomyopathy. By contrast, the variant is embryonically lethal in the homozygous setting and E15.5 hearts show multiple morphological abnormalities. Molecular analyses, including unbiased proteomics, identified quantitative abnormalities in sarcomeric parameters, cell-cycle defects and mitochondrial dysfunction. The mutant alpha-actinin protein is found to be destabilised, associated with increased activity of the ubiquitin-proteasomal system. This missense variant in alpha-actinin renders the protein less stable. In response, the ubiquitin-proteasomal system is activated; a mechanism that has been implicated in cardiomyopathies previously. In parallel, a lack of functional alpha-actinin is thought to cause energetic defects through mitochondrial dysfunction. This seems, together with cell-cycle defects, the likely cause of the death of the embryos. The defects also have wide-ranging morphological consequences.
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Affiliation(s)
| | - He Jiang
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
| | - Kirsty Wadmore
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Charlotte Hooper
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
| | - Gillian Douglas
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
| | - Violetta Steeples
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
| | - Amar J. Azad
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Evie Singer
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Jasmeet S. Reyat
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Frantisek Galatik
- Department of Physiology, Faculty of Science, Charles University, 12800 Prague, Czech Republic
| | - Elisabeth Ehler
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 9RT, UK
- School of Cardiovascular and Metabolic Medicine and Sciences, British Heart Foundation Centre of Research Excellence, King’s College London, London SE1 9RT, UK
| | - Pauline Bennett
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London SE1 9RT, UK
| | | | - Duncan B. Sparrow
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Benjamin Davies
- Transgenic Core, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Kristina Djinovic-Carugo
- European Molecular Biology Laboratory, 38000 Grenoble, France
- Department of Structural and Computational Biology, Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
| | - Mathias Gautel
- School of Basic and Medical Biosciences, British Heart Foundation Centre of Research Excellence, King’s College London, London SE1 9RT, UK
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
| | - Katja Gehmlich
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, UK
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence Oxford, University of Oxford, Oxford OX3 9DU, UK
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3
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Paez HG, Pitzer CR, Alway SE. Age-Related Dysfunction in Proteostasis and Cellular Quality Control in the Development of Sarcopenia. Cells 2023; 12:cells12020249. [PMID: 36672183 PMCID: PMC9856405 DOI: 10.3390/cells12020249] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/04/2023] [Accepted: 01/04/2023] [Indexed: 01/11/2023] Open
Abstract
Sarcopenia is a debilitating skeletal muscle disease that accelerates in the last decades of life and is characterized by marked deficits in muscle strength, mass, quality, and metabolic health. The multifactorial causes of sarcopenia have proven difficult to treat and involve a complex interplay between environmental factors and intrinsic age-associated changes. It is generally accepted that sarcopenia results in a progressive loss of skeletal muscle function that exceeds the loss of mass, indicating that while loss of muscle mass is important, loss of muscle quality is the primary defect with advanced age. Furthermore, preclinical models have suggested that aged skeletal muscle exhibits defects in cellular quality control such as the degradation of damaged mitochondria. Recent evidence suggests that a dysregulation of proteostasis, an important regulator of cellular quality control, is a significant contributor to the aging-associated declines in muscle quality, function, and mass. Although skeletal muscle mammalian target of rapamycin complex 1 (mTORC1) plays a critical role in cellular control, including skeletal muscle hypertrophy, paradoxically, sustained activation of mTORC1 recapitulates several characteristics of sarcopenia. Pharmaceutical inhibition of mTORC1 as well as caloric restriction significantly improves muscle quality in aged animals, however, the mechanisms controlling cellular proteostasis are not fully known. This information is important for developing effective therapeutic strategies that mitigate or prevent sarcopenia and associated disability. This review identifies recent and historical understanding of the molecular mechanisms of proteostasis driving age-associated muscle loss and suggests potential therapeutic interventions to slow or prevent sarcopenia.
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Affiliation(s)
- Hector G. Paez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Christopher R. Pitzer
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Stephen E. Alway
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Integrated Biomedical Sciences Graduate Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Laboratory of Muscle Biology and Sarcopenia, Department of Physical Therapy, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- Center for Muscle, Metabolism and Neuropathology, Division of Regenerative and Rehabilitation Sciences, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN 38163, USA
- The Tennessee Institute of Regenerative Medicine, Memphis, TN 38163, USA
- Correspondence:
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4
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Kaiser MS, Milan G, Ham DJ, Lin S, Oliveri F, Chojnowska K, Tintignac LA, Mittal N, Zimmerli CE, Glass DJ, Zavolan M, Rüegg MA. Dual roles of mTORC1-dependent activation of the ubiquitin-proteasome system in muscle proteostasis. Commun Biol 2022; 5:1141. [PMID: 36302954 PMCID: PMC9613904 DOI: 10.1038/s42003-022-04097-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 10/11/2022] [Indexed: 12/02/2022] Open
Abstract
Muscle size is controlled by the PI3K-PKB/Akt-mTORC1-FoxO pathway, which integrates signals from growth factors, energy and amino acids to activate protein synthesis and inhibit protein breakdown. While mTORC1 activity is necessary for PKB/Akt-induced muscle hypertrophy, its constant activation alone induces muscle atrophy. Here we show that this paradox is based on mTORC1 activity promoting protein breakdown through the ubiquitin-proteasome system (UPS) by simultaneously inducing ubiquitin E3 ligase expression via feedback inhibition of PKB/Akt and proteasome biogenesis via Nuclear Factor Erythroid 2-Like 1 (Nrf1). Muscle growth was restored by reactivation of PKB/Akt, but not by Nrf1 knockdown, implicating ubiquitination as the limiting step. However, both PKB/Akt activation and proteasome depletion by Nrf1 knockdown led to an immediate disruption of proteome integrity with rapid accumulation of damaged material. These data highlight the physiological importance of mTORC1-mediated PKB/Akt inhibition and point to juxtaposed roles of the UPS in atrophy and proteome integrity. Exploring the relationship between mTORC1 and the ubiquitin-proteasome system, light is shed on the paradox between mTORC1-mediated muscle hypertrophy induced by PKB/Akt and the muscle atrophy induced by mTORC1 alone.
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Affiliation(s)
- Marco S Kaiser
- Biozentrum, University of Basel, Basel, Switzerland.,BIOREBA AG, Christoph Merian-Ring 7, 4153, Reinach, Switzerland
| | - Giulia Milan
- Biozentrum, University of Basel, Basel, Switzerland. .,Department of Biomedicine, University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland.
| | - Daniel J Ham
- Biozentrum, University of Basel, Basel, Switzerland.
| | - Shuo Lin
- Biozentrum, University of Basel, Basel, Switzerland
| | | | - Kathrin Chojnowska
- Biozentrum, University of Basel, Basel, Switzerland.,AstraZeneca AG, Neuhofstrasse 34, 6340, Baar, Switzerland
| | - Lionel A Tintignac
- Biozentrum, University of Basel, Basel, Switzerland.,Neuromuscular Research Group, Departments of Neurology and Biomedicine, University of Basel, University Hospital Basel, Basel, Switzerland
| | | | - Christian E Zimmerli
- Biozentrum, University of Basel, Basel, Switzerland.,Department of Molecular Sociology, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany
| | - David J Glass
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA.,Regeneron Pharmaceuticals, Tarrytown, NY, USA
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5
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Hughes DC, Baehr LM, Waddell DS, Sharples AP, Bodine SC. Ubiquitin Ligases in Longevity and Aging Skeletal Muscle. Int J Mol Sci 2022; 23:7602. [PMID: 35886949 PMCID: PMC9315556 DOI: 10.3390/ijms23147602] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 12/07/2022] Open
Abstract
The development and prevalence of diseases associated with aging presents a global health burden on society. One hallmark of aging is the loss of proteostasis which is caused in part by alterations to the ubiquitin-proteasome system (UPS) and lysosome-autophagy system leading to impaired function and maintenance of mass in tissues such as skeletal muscle. In the instance of skeletal muscle, the impairment of function occurs early in the aging process and is dependent on proteostatic mechanisms. The UPS plays a pivotal role in degradation of misfolded and aggregated proteins. For the purpose of this review, we will discuss the role of the UPS system in the context of age-related loss of muscle mass and function. We highlight the significant role that E3 ubiquitin ligases play in the turnover of key components (e.g., mitochondria and neuromuscular junction) essential to skeletal muscle function and the influence of aging. In addition, we will briefly discuss the contribution of the UPS system to lifespan. By understanding the UPS system as part of the proteostasis network in age-related diseases and disorders such as sarcopenia, new discoveries can be made and new interventions can be developed which will preserve muscle function and maintain quality of life with advancing age.
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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 52242, USA; (L.M.B.); (S.C.B.)
| | - Leslie M. Baehr
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (L.M.B.); (S.C.B.)
| | - David S. Waddell
- Department of Biology, University of North Florida, Jacksonville, FL 32224, USA;
| | - Adam P. Sharples
- Institute for Physical Performance, Norwegian School of Sport Sciences (NiH), 0863 Oslo, Norway;
| | - Sue C. Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (L.M.B.); (S.C.B.)
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6
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Wilburn D, Ismaeel A, Machek S, Fletcher E, Koutakis P. Shared and distinct mechanisms of skeletal muscle atrophy: A narrative review. Ageing Res Rev 2021; 71:101463. [PMID: 34534682 DOI: 10.1016/j.arr.2021.101463] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/30/2021] [Accepted: 09/11/2021] [Indexed: 12/15/2022]
Abstract
Maintenance of skeletal muscle mass and function is an incredibly nuanced balance of anabolism and catabolism that can become distorted within different pathological conditions. In this paper we intend to discuss the distinct intracellular signaling events that regulate muscle protein atrophy for a given clinical occurrence. Aside from the common outcome of muscle deterioration, several conditions have at least one or more distinct mechanisms that creates unique intracellular environments that facilitate muscle loss. The subtle individuality to each of these given pathologies can provide both researchers and clinicians with specific targets of interest to further identify and increase the efficacy of medical treatments and interventions.
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Affiliation(s)
- Dylan Wilburn
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA
| | - Ahmed Ismaeel
- Department of Biology, Baylor University, Waco, TX 76706, USA
| | - Steven Machek
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA
| | - Emma Fletcher
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA; Department of Biology, Baylor University, Waco, TX 76706, USA
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7
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Hanna AD, Lee CS, Babcock L, Wang H, Recio J, Hamilton SL. Pathological mechanisms of vacuolar aggregate myopathy arising from a Casq1 mutation. FASEB J 2021; 35:e21349. [PMID: 33786938 DOI: 10.1096/fj.202001653rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 12/15/2020] [Accepted: 12/22/2020] [Indexed: 11/11/2022]
Abstract
Mice with a mutation (D244G, DG) in calsequestrin 1 (CASQ1), analogous to a human mutation in CASQ1 associated with a delayed onset human myopathy (vacuolar aggregate myopathy), display a progressive myopathy characterized by decreased activity, decreased ability of fast twitch muscles to generate force and low body weight after one year of age. The DG mutation causes CASQ1 to partially dissociate from the junctional sarcoplasmic reticulum (SR) and accumulate in the endoplasmic reticulum (ER). Decreased junctional CASQ1 reduces SR Ca2+ release. Muscles from older DG mice display ER stress, ER expansion, increased mTOR signaling, inadequate clearance of aggregated proteins by the proteasomes, and elevation of protein aggregates and lysosomes. This study suggests that the myopathy associated with the D244G mutation in CASQ1 is driven by CASQ1 mislocalization, reduced SR Ca2+ release, CASQ1 misfolding/aggregation and ER stress. The subsequent maladaptive increase in protein synthesis and decreased protein aggregate clearance are likely to contribute to disease progression.
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Affiliation(s)
- Amy D Hanna
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Chang Seok Lee
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Lyle Babcock
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Hui Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Joseph Recio
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Susan L Hamilton
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
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8
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Wiedmer P, Jung T, Castro JP, Pomatto LC, Sun PY, Davies KJ, Grune T. Sarcopenia - Molecular mechanisms and open questions. Ageing Res Rev 2021; 65:101200. [PMID: 33130247 DOI: 10.1016/j.arr.2020.101200] [Citation(s) in RCA: 174] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/18/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022]
Abstract
Sarcopenia represents a muscle-wasting syndrome characterized by progressive and generalized degenerative loss of skeletal muscle mass, quality, and strength occurring during normal aging. Sarcopenia patients are mainly suffering from the loss in muscle strength and are faced with mobility disorders reducing their quality of life and are, therefore, at higher risk for morbidity (falls, bone fracture, metabolic diseases) and mortality. Several molecular mechanisms have been described as causes for sarcopenia that refer to very different levels of muscle physiology. These mechanisms cover e. g. function of hormones (e. g. IGF-1 and Insulin), muscle fiber composition and neuromuscular drive, myo-satellite cell potential to differentiate and proliferate, inflammatory pathways as well as intracellular mechanisms in the processes of proteostasis and mitochondrial function. In this review, we describe sarcopenia as a muscle-wasting syndrome distinct from other atrophic diseases and summarize the current view on molecular causes of sarcopenia development as well as open questions provoking further research efforts for establishing efficient lifestyle and therapeutic interventions.
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9
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Knapp F, Niemann B, Li L, Molenda N, Kracht M, Schulz R, Rohrbach S. Differential effects of right and left heart failure on skeletal muscle in rats. J Cachexia Sarcopenia Muscle 2020; 11:1830-1849. [PMID: 32985798 PMCID: PMC7749622 DOI: 10.1002/jcsm.12612] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 05/17/2020] [Accepted: 07/07/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Exercise intolerance is a cardinal symptom in right (RV) and left ventricular (LV) failure. The underlying skeletal muscle contributes to increased morbidity in patients. Here, we compared skeletal muscle sarcopenia in a novel two-stage model of RV failure to an established model of LV failure. METHODS Pulmonary artery banding (PAB) or aortic banding (AOB) was performed in weanling rats, inducing a transition from compensated cardiac hypertrophy (after 7 weeks) to heart failure (after 22-26 weeks). Cardiac function was characterized by echocardiography. Skeletal muscle catabolic/anabolic balance and energy metabolism were analysed by histological and biochemical methods, real-time PCR, and western blot. RESULTS Two clearly distinguishable stages of left or right heart disease with a comparable severity were reached. However, skeletal muscle impairment was significantly more pronounced in LV failure. While the compensatory stage resulted only in minor changes, soleus and gastrocnemius muscle of AOB rats at the decompensated stage demonstrated reduced weight and fibre diameter, higher proteasome activity and expression of the muscle-specific ubiquitin E3 ligases muscle-specific RING finger 1 and atrogin-1, increased expression of the atrophy marker myostatin, increased autophagy activation, and impaired mitochondrial function and respiratory chain gene expression. Soleus and gastrocnemius muscle of PAB rats did not show significant changes in muscle weight and proteasome or autophagy activation, but mitochondrial function was mildly impaired as well. The diaphragm did not demonstrate differences in any model or disease stage except for myostatin expression, which was altered at the decompensated stage in both models. Plasma interleukin (IL)-6 and angiotensin II were strongly increased at the decompensated stage (AOB > > PAB). Soleus and gastrocnemius muscle itself demonstrated an increase in IL-6 expression independent from blood-derived cytokines only in AOB animals. In vitro experiments in rat skeletal muscle cells suggested a direct impact of IL-6 and angiotensin II on distinctive atrophic changes. CONCLUSIONS Manifold skeletal muscle alterations are more pronounced in LV failure compared with RV failure despite a similar ventricular impairment. Most of the catabolic changes were observed in soleus or gastrocnemius muscle rather than in the constantly active diaphragm. Mitochondrial dysfunction and up-regulation of myostatin were identified as the earliest signs of skeletal muscle impairment.
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Affiliation(s)
- Fabienne Knapp
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Bernd Niemann
- Department of Adult and Pediatric Cardiac and Vascular Surgery, University Hospital Giessen and Marburg, Justus Liebig University Giessen, Rudolf-Buchheim-Strasse 7, Giessen, 35392, Germany
| | - Ling Li
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Nicole Molenda
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Michael Kracht
- Rudolf Buchheim Institute of Pharmacology, Justus Liebig University Giessen, Schubertstrasse 81, Giessen, 35392, Germany
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
| | - Susanne Rohrbach
- Institute of Physiology, Justus Liebig University Giessen, Giessen, Germany
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10
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The dialogue between the ubiquitin-proteasome system and autophagy: Implications in ageing. Ageing Res Rev 2020; 64:101203. [PMID: 33130248 DOI: 10.1016/j.arr.2020.101203] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/09/2020] [Accepted: 10/25/2020] [Indexed: 02/06/2023]
Abstract
Dysregulated proteostasis is one of the hallmarks of ageing. Damaged proteins may impair cellular function and their accumulation may lead to tissue dysfunction and disease. This is why protective mechanisms to safeguard the cell proteome have evolved. These mechanisms consist of cellular machineries involved in protein quality control, including regulators of protein translation, folding, trafficking and degradation. In eukaryotic cells, protein degradation occurs via two main pathways: the ubiquitin-proteasome system (UPS) and the autophagy-lysosome pathway. Although distinct pathways, they are not isolated systems and have a complementary nature, as evidenced by recent studies. These findings raise the question of how autophagy and the proteasome crosstalk. In this review we address how the two degradation pathways impact each other, thereby adding a new layer of regulation to protein degradation. We also analyze the implications of the UPS and autophagy in ageing.
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11
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Docosahexaenoic Acid, a Potential Treatment for Sarcopenia, Modulates the Ubiquitin-Proteasome and the Autophagy-Lysosome Systems. Nutrients 2020; 12:nu12092597. [PMID: 32859116 PMCID: PMC7551806 DOI: 10.3390/nu12092597] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/22/2020] [Accepted: 08/24/2020] [Indexed: 12/14/2022] Open
Abstract
One of the characteristic features of aging is the progressive loss of muscle mass, a nosological syndrome called sarcopenia. It is also a pathologic risk factor for many clinically adverse outcomes in older adults. Therefore, delaying the loss of muscle mass, through either boosting muscle protein synthesis or slowing down muscle protein degradation using nutritional supplements could be a compelling strategy to address the needs of the world’s aging population. Here, we review the recently identified properties of docosahexaenoic acid (DHA). It was shown to delay muscle wasting by stimulating intermediate oxidative stress and inhibiting proteasomal degradation of muscle proteins. Both the ubiquitin–proteasome and the autophagy–lysosome systems are modulated by DHA. Collectively, growing evidence indicates that DHA is a potent pharmacological agent that could improve muscle homeostasis. Better understanding of cellular proteolytic systems associated with sarcopenia will allow us to identify novel therapeutic interventions, such as omega-3 polyunsaturated fatty acids, to treat this disease.
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12
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Lu F, Lu B, Zhang L, Wen J, Wang M, Zhang S, Li Q, Shu F, Sun Y, Liu N, Peng S, Zhao Y, Dong S, Zhao D, Lu F, Zhang W. Hydrogen sulphide ameliorating skeletal muscle atrophy in db/db mice via Muscle RING finger 1 S-sulfhydration. J Cell Mol Med 2020; 24:9362-9377. [PMID: 32633463 PMCID: PMC7417732 DOI: 10.1111/jcmm.15587] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 06/04/2020] [Accepted: 06/06/2020] [Indexed: 12/25/2022] Open
Abstract
Muscle atrophy occurs in many pathological states, including cancer, diabetes and sepsis, whose results primarily from accelerated protein degradation and activation of the ubiquitin‐proteasome pathway. Expression of Muscle RING finger 1 (MuRF1), an E3 ubiquitin ligase, was increased to induce the loss of muscle mass in diabetic condition. However, hydrogen sulphide (H2S) plays a crucial role in the variety of physiological functions, including antihypertension, antiproliferation and antioxidant. In this study, db/db mice and C2C12 myoblasts treated by high glucose and palmitate and oleate were chose as animal and cellular models. We explored how exogenous H2S attenuated the degradation of skeletal muscle via the modification of MuRF1 S‐sulfhydration in db/db mice. Our results show cystathionine‐r‐lyase expression, and H2S level in skeletal muscle of db/db mice was reduced. Simultaneously, exogenous H2S could alleviate ROS production and reverse expression of ER stress protein markers. Exogenous H2S could decrease the ubiquitination level of MYOM1 and MYH4 in db/db mice. In addition, exogenous H2S reduced the interaction between MuRF1 with MYOM1 and MYH4 via MuRF1 S‐sulfhydration. Based on these results, we establish that H2S prevented the degradation of skeletal muscle via MuRF1 S‐sulfhydration at the site of Cys44 in db/db mice.
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Affiliation(s)
- Fangping Lu
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Baoling Lu
- Department of Infectious, The Fourth Hospital of Harbin Medical University, Harbin, China
| | - Linxue Zhang
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - JingChen Wen
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Mengyi Wang
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Shiwu Zhang
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Qianzhu Li
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Feng Shu
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Yu Sun
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Ning Liu
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Shuo Peng
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Yajun Zhao
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Shiyun Dong
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Dechao Zhao
- Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Fanghao Lu
- Department of Pathophysiology, Harbin Medical University, Harbin, China
| | - Weihua Zhang
- Department of Pathophysiology, Harbin Medical University, Harbin, China
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13
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Karow M, Fischer S, Meßling S, Konertz R, Riehl J, Xiong Q, Rijal R, Wagle P, S. Clemen C, Eichinger L. Functional Characterisation of the Autophagy ATG12~5/16 Complex in Dictyostelium discoideum. Cells 2020; 9:cells9051179. [PMID: 32397394 PMCID: PMC7290328 DOI: 10.3390/cells9051179] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/21/2022] Open
Abstract
Macroautophagy, a highly conserved and complex intracellular degradative pathway, involves more than 20 core autophagy (ATG) proteins, among them the hexameric ATG12~5/16 complex, which is part of the essential ubiquitin-like conjugation systems in autophagy. Dictyostelium discoideumatg5 single, atg5/12 double, and atg5/12/16 triple gene knock-out mutant strains displayed similar defects in the conjugation of ATG8 to phosphatidylethanolamine, development, and cell viability upon nitrogen starvation. This implies that ATG5, 12 and 16 act as a functional unit in canonical autophagy. Macropinocytosis of TRITC dextran and phagocytosis of yeast were significantly decreased in ATG5¯ and ATG5¯/12¯ and even further in ATG5¯/12¯/16¯ cells. In contrast, plaque growth on Klebsiella aerogenes was about twice as fast for ATG5¯ and ATG5¯/12¯/16¯ cells in comparison to AX2, but strongly decreased for ATG5¯/12¯ cells. Along this line, phagocytic uptake of Escherichia coli was significantly reduced in ATG5¯/12¯ cells, while no difference in uptake, but a strong increase in membrane association of E. coli, was seen for ATG5¯ and ATG5¯/12¯/16¯ cells. Proteasomal activity was also disturbed in a complex fashion, consistent with an inhibitory activity of ATG16 in the absence of ATG5 and/or ATG12. Our results confirm the essential function of the ATG12~5/16 complex in canonical autophagy, and furthermore are consistent with autophagy-independent functions of the complex and its individual components. They also strongly support the placement of autophagy upstream of the ubiquitin-proteasome system (UPS), as a fully functional UPS depends on autophagy.
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Affiliation(s)
- Malte Karow
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
| | - Sarah Fischer
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
| | - Susanne Meßling
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
| | - Roman Konertz
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
| | - Jana Riehl
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
| | - Qiuhong Xiong
- Institute of Biomedical Sciences, Shanxi University, No. 92 Wucheng Road, Taiyuan 030006, China;
| | - Ramesh Rijal
- Department of Biology, Texas A&M University, College Station, TX 77843-3474, USA;
| | - Prerana Wagle
- Bioinformatics Core Facility, CECAD Research Center, University of Cologne, 50931 Cologne, Germany;
| | - Christoph S. Clemen
- Institute of Aerospace Medicine, German Aerospace Center (DLR), 51147 Cologne, Germany;
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty, University of Cologne, 50931 Cologne, Germany
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Ludwig Eichinger
- Centre for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931 Cologne, Germany; (M.K.); (S.F.); (S.M.); (R.K.); (J.R.)
- Correspondence: ; Tel.: +49-221-478-6928; Fax: +49-221-478-97524
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14
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Raz Y, Akker EB, Roest T, Riaz M, Rest O, Suchiman HED, Lakenberg N, Stassen SA, Putten M, Feskens EJM, Reinders MJT, Goeman J, Beekman M, Raz V, Slagboom PE. A data‐driven methodology reveals novel myofiber clusters in older human muscles. FASEB J 2020; 34:5525-5537. [DOI: 10.1096/fj.201902350r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 01/07/2020] [Accepted: 02/13/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Yotam Raz
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
| | - Erik B. Akker
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
- Leiden Computational Biology Center Leiden University Medical Center Leiden the Netherlands
- The Delft Bioinformatics Lab Delft University of Technology Delft the Netherlands
| | - Tijmen Roest
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
| | - Muhammad Riaz
- Department of Human Genetics Leiden University Medical Center Leiden the Netherlands
| | - Ondine Rest
- Division of Human Nutrition Wageningen University & Research Wageningen the Netherlands
| | - H. Eka D. Suchiman
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
| | - Nico Lakenberg
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
| | - Stefanie A. Stassen
- Section of Gerontology and Geriatrics Leiden University Medical Center Leiden the Netherlands
| | - Maaike Putten
- Department of Human Genetics Leiden University Medical Center Leiden the Netherlands
| | - Edith J. M. Feskens
- Division of Human Nutrition Wageningen University & Research Wageningen the Netherlands
| | - Marcel J. T. Reinders
- Leiden Computational Biology Center Leiden University Medical Center Leiden the Netherlands
- The Delft Bioinformatics Lab Delft University of Technology Delft the Netherlands
| | - Jelle Goeman
- Department of Medical Statistics Leiden University Medical Center Leiden the Netherlands
| | - Marian Beekman
- Section of Molecular Epidemiology Leiden University Medical Center Leiden the Netherlands
| | - Vered Raz
- Department of Human Genetics Leiden University Medical Center Leiden the Netherlands
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15
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Hayat B, Padhy B, Mohanty PP, Alone DP. Altered unfolded protein response and proteasome impairment in pseudoexfoliation pathogenesis. Exp Eye Res 2019; 181:197-207. [DOI: 10.1016/j.exer.2019.02.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/03/2019] [Accepted: 02/04/2019] [Indexed: 02/02/2023]
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16
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Fernando R, Drescher C, Deubel S, Jung T, Ost M, Klaus S, Grune T, Castro JP. Low proteasomal activity in fast skeletal muscle fibers is not associated with increased age-related oxidative damage. Exp Gerontol 2019; 117:45-52. [DOI: 10.1016/j.exger.2018.10.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 10/09/2018] [Accepted: 10/23/2018] [Indexed: 01/07/2023]
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17
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Fernando R, Drescher C, Nowotny K, Grune T, Castro JP. Impaired proteostasis during skeletal muscle aging. Free Radic Biol Med 2019; 132:58-66. [PMID: 30194981 DOI: 10.1016/j.freeradbiomed.2018.08.037] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 08/03/2018] [Accepted: 08/30/2018] [Indexed: 01/03/2023]
Abstract
Aging is a complex phenomenon that has detrimental effects on tissue homeostasis. The skeletal muscle is one of the earliest tissues to be affected and to manifest age-related changes such as functional impairment and the loss of mass. Common to these alterations and to most of tissues during aging is the disruption of the proteostasis network by detrimental changes in the ubiquitin-proteasomal system (UPS) and the autophagy-lysosomal system (ALS). In fact, during aging the accumulation of protein aggregates, a process mainly driven by increased levels of oxidative stress, has been observed, clearly demonstrating UPS and ALS dysregulation. Since the UPS and ALS are the two most important pathways for the removal of misfolded and aggregated proteins and also of damaged organelles, we provide here an overview on the current knowledge regarding the connection between the loss of proteostasis and skeletal muscle functional impairment and also how redox regulation can play a role during aging. Therefore, this review serves for a better understanding of skeletal muscle aging in regard to the loss of proteostasis and how redox regulation can impact its function and maintenance.
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Affiliation(s)
- Raquel Fernando
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
| | - Cathleen Drescher
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
| | - Kerstin Nowotny
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764 München-Neuherberg, Germany; German Center for Cardiovascular Research (DZHK), 10117 Berlin, Germany; University of Potsdam, Institute of Nutritional Science, 14558 Nuthetal, Germany
| | - José Pedro Castro
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558 Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764 München-Neuherberg, Germany; Faculty of Medicine, Department for Biomedicine, University of Porto, 4200-319, Portugal; Institute for Innovation and Health Research (I3S), Aging and Stress Group, R. Alfredo Allen, 4200-135 Porto, Portugal.
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18
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Functional Characterization of Ubiquitin-Like Core Autophagy Protein ATG12 in Dictyostelium discoideum. Cells 2019; 8:cells8010072. [PMID: 30669443 PMCID: PMC6356199 DOI: 10.3390/cells8010072] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/15/2019] [Accepted: 01/17/2019] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a highly conserved intracellular degradative pathway that is crucial for cellular homeostasis. During autophagy, the core autophagy protein ATG12 plays, together with ATG5 and ATG16, an essential role in the expansion of the autophagosomal membrane. In this study we analyzed gene replacement mutants of atg12 in Dictyostelium discoideum AX2 wild-type and ATG16‾ cells. RNAseq analysis revealed a strong enrichment of, firstly, autophagy genes among the up-regulated genes and, secondly, genes implicated in cell motility and phagocytosis among the down-regulated genes in the generated ATG12‾, ATG16‾ and ATG12‾/16‾ cells. The mutant strains showed similar defects in fruiting body formation, autolysosome maturation, and cellular viability, implying that ATG12 and ATG16 act as a functional unit in canonical autophagy. In contrast, ablation of ATG16 or of ATG12 and ATG16 resulted in slightly more severe defects in axenic growth, macropinocytosis, and protein homeostasis than ablation of only ATG12, suggesting that ATG16 fulfils an additional function in these processes. Phagocytosis of yeast, spore viability, and maximal cell density were much more affected in ATG12‾/16‾ cells, indicating that both proteins also have cellular functions independent of each other. In summary, we show that ATG12 and ATG16 fulfil autophagy-independent functions in addition to their role in canonical autophagy.
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19
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Picher-Martel V, Renaud L, Bareil C, Julien JP. Neuronal Expression of UBQLN2 P497H Exacerbates TDP-43 Pathology in TDP-43 G348C Mice through Interaction with Ubiquitin. Mol Neurobiol 2018; 56:4680-4696. [PMID: 30377984 PMCID: PMC6647471 DOI: 10.1007/s12035-018-1411-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 10/24/2018] [Indexed: 12/11/2022]
Abstract
Mutations in the gene encoding ubiquilin-2 (UBQLN2) are linked to amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). UBQLN2 plays a central role in ubiquitin proteasome system (UPS) and UBQLN2 up-regulation exacerbates TDP-43 cytoplasmic aggregates. To analyze interaction between UBQLN2 and TDP-43 and to produce a relevant ALS animal model, we have generated a new transgenic mouse expressing UBQLN2P497H under the neurofilament heavy (NFH) gene promoter. The UBQLN2P497H mice were then bred with our previously described TDP-43G348C mice to generate double-transgenic UBQLN2P497H; TDP-43G348C mice. With low-expression levels of UBQLN2, the double-transgenic mice developed TDP-43 cytosolic accumulations in motor neurons starting at 5 months of age. These double-transgenic mice exhibited motor neuron loss, muscle atrophy, as well as motor and cognitive deficits during aging. The microglia from double-transgenic mice were hyperresponsive to intraperitoneal injection of lipopolysaccharide (LPS). In vivo and in vitro analyses suggested that extra UBQLN2 proteins can exacerbate cytoplasmic TDP-43 accumulations by competing with the UPS for binding to ubiquitin. Thus, increasing the pool of ubiquitin promoted the UPS function with ensuing reduction of TDP-43 cytosolic accumulations. In conclusion, the double-transgenic UBQLN2P497H; TDP-43G348C mice provides a unique mouse model of ALS/FTD with enhanced TDP-43 pathology that can be exploited for drug testing.
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Affiliation(s)
- Vincent Picher-Martel
- Department of Psychiatry and Neuroscience, Laval University, Quebec, Canada.,CERVO Brain Research Centre, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada
| | - Laurence Renaud
- Department of Psychiatry and Neuroscience, Laval University, Quebec, Canada.,CERVO Brain Research Centre, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada
| | - Christine Bareil
- CERVO Brain Research Centre, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada
| | - Jean-Pierre Julien
- Department of Psychiatry and Neuroscience, Laval University, Quebec, Canada. .,CERVO Brain Research Centre, 2601 Chemin de la Canardière, Québec, QC, G1J 2G3, Canada.
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20
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Winter L, Unger A, Berwanger C, Spörrer M, Türk M, Chevessier F, Strucksberg KH, Schlötzer-Schrehardt U, Wittig I, Goldmann WH, Marcus K, Linke WA, Clemen CS, Schröder R. Imbalances in protein homeostasis caused by mutant desmin. Neuropathol Appl Neurobiol 2018; 45:476-494. [PMID: 30179276 DOI: 10.1111/nan.12516] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/17/2018] [Indexed: 12/19/2022]
Abstract
AIMS We investigated newly generated immortalized heterozygous and homozygous R349P desmin knock-in myoblasts in conjunction with the corresponding desminopathy mice as models for desminopathies to analyse major protein quality control processes in response to the presence of R349P mutant desmin. METHODS We used hetero- and homozygous R349P desmin knock-in mice for analyses and for crossbreeding with p53 knock-out mice to generate immortalized R349P desmin knock-in skeletal muscle myoblasts and myotubes. Skeletal muscle sections and cultured muscle cells were investigated by indirect immunofluorescence microscopy, proteasomal activity measurements and immunoblotting addressing autophagy rate, chaperone-assisted selective autophagy and heat shock protein levels. Muscle sections were further analysed by transmission and immunogold electron microscopy. RESULTS We demonstrate that mutant desmin (i) increases proteasomal activity, (ii) stimulates macroautophagy, (iii) dysregulates the chaperone assisted selective autophagy and (iv) elevates the protein levels of αB-crystallin and Hsp27. Both αB-crystallin and Hsp27 as well as Hsp90 displayed translocation patterns from Z-discs as well as Z-I junctions, respectively, to the level of sarcomeric I-bands in dominant and recessive desminopathies. CONCLUSIONS Our findings demonstrate that the presence of R349P mutant desmin causes a general imbalance in skeletal muscle protein homeostasis via aberrant activity of all major protein quality control systems. The augmented activity of these systems and the subcellular shift of essential heat shock proteins may deleteriously contribute to the previously observed increased turnover of desmin itself and desmin-binding partners, which triggers progressive dysfunction of the extrasarcomeric cytoskeleton and the myofibrillar apparatus in the course of the development of desminopathies.
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Affiliation(s)
- L Winter
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany.,Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - A Unger
- Department of Cardiovascular Physiology, Ruhr-University Bochum, Bochum, Germany.,Institute for Genetics of Heart Diseases, University Hospital Münster, Münster, Germany
| | - C Berwanger
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany.,Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - M Spörrer
- Center for Medical Physics and Technology, Biophysics Group, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - M Türk
- Department of Neurology, University Hospital Erlangen, Erlangen, Germany
| | - F Chevessier
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - K-H Strucksberg
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | | | - I Wittig
- Functional Proteomics, SFB815 Core Unit, Medical School, Goethe University, Frankfurt, Germany
| | - W H Goldmann
- Center for Medical Physics and Technology, Biophysics Group, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - K Marcus
- Medizinisches Proteom-Center, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - W A Linke
- Department of Cardiovascular Physiology, Ruhr-University Bochum, Bochum, Germany.,Institute of Physiology II, University of Münster, Münster, Germany
| | - C S Clemen
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany.,Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - R Schröder
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
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21
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Clemen CS, Winter L, Strucksberg KH, Berwanger C, Türk M, Kornblum C, Florin A, Aguilar-Pimentel JA, Amarie OV, Becker L, Garrett L, Hans W, Moreth K, Neff F, Pingen L, Rathkolb B, Rácz I, Rozman J, Treise I, Fuchs H, Gailus-Durner V, de Angelis MH, Vorgerd M, Eichinger L, Schröder R. The heterozygous R155C VCP mutation: Toxic in humans! Harmless in mice? Biochem Biophys Res Commun 2018; 503:2770-2777. [PMID: 30100055 DOI: 10.1016/j.bbrc.2018.08.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 08/04/2018] [Indexed: 12/12/2022]
Abstract
Heterozygous missense mutations in the human VCP gene cause inclusion body myopathy associated with Paget disease of bone and fronto-temporal dementia (IBMPFD) and amyotrophic lateral sclerosis (ALS). The exact molecular mechanisms by which VCP mutations cause disease manifestation in different tissues are incompletely understood. In the present study, we report the comprehensive analysis of a newly generated R155C VCP knock-in mouse model, which expresses the ortholog of the second most frequently occurring human pathogenic VCP mutation. Heterozygous R155C VCP knock-in mice showed decreased plasma lactate, serum albumin and total protein concentrations, platelet numbers, and liver to body weight ratios, and increased oxygen consumption and CD8+/Ly6C + T-cell fractions, but none of the typical human IBMPFD or ALS pathologies. Breeding of heterozygous mice did not yield in the generation of homozygous R155C VCP knock-in animals. Immunoblotting showed identical total VCP protein levels in human IBMPFD and murine R155C VCP knock-in tissues as compared to wild-type controls. However, while in human IBMPFD skeletal muscle tissue 70% of the total VCP mRNA was derived from the mutant allele, in R155C VCP knock-in mice only 5% and 7% mutant mRNA were detected in skeletal muscle and brain tissue, respectively. The lack of any obvious IBMPFD or ALS pathology could thus be a consequence of the very low expression of mutant VCP. We conclude that the increased and decreased fractions of the R155C mutant VCP mRNA in man and mice, respectively, are due to missense mutation-induced, divergent alterations in the biological half-life of the human and murine mutant mRNAs. Furthermore, our work suggests that therapy approaches lowering the expression of the mutant VCP mRNA below a critical threshold may ameliorate the intrinsic disease pathology.
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Affiliation(s)
- Christoph S Clemen
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44789, Bochum, Germany; Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931, Cologne, Germany.
| | - Lilli Winter
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, 91054, Erlangen, Germany; Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna, 1090, Vienna, Austria
| | - Karl-Heinz Strucksberg
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931, Cologne, Germany
| | - Carolin Berwanger
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44789, Bochum, Germany; Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931, Cologne, Germany
| | - Matthias Türk
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, 91054, Erlangen, Germany
| | - Cornelia Kornblum
- Department of Neurology, University Hospital Bonn, 53125, Bonn, Germany; Center for Rare Diseases Bonn, University Hospital Bonn, 53127, Bonn, Germany
| | - Alexandra Florin
- Institute for Pathology, University Hospital Cologne, 50937, Cologne, Germany
| | - Juan Antonio Aguilar-Pimentel
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Oana Veronica Amarie
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Lore Becker
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Lillian Garrett
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Wolfgang Hans
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Kristin Moreth
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Frauke Neff
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; Institute of Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Laura Pingen
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Birgit Rathkolb
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; Institute of Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-University München, 81377, Munich, Germany; German Center for Diabetes Research (DZD), 85764, Neuherberg, Germany
| | - Ildikó Rácz
- Institute of Molecular Psychiatry, Medical Faculty, University of Bonn, 53127, Bonn, Germany; Clinic of Neurodegenerative Diseases and Gerontopsychiatry, University of Bonn Medical Center, 53127, Bonn, Germany
| | - Jan Rozman
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764, Neuherberg, Germany
| | - Irina Treise
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Valerie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Martin Hrabe de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, 85764, Neuherberg, Germany; German Center for Diabetes Research (DZD), 85764, Neuherberg, Germany; Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, 85354, Freising, Germany
| | - Matthias Vorgerd
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44789, Bochum, Germany
| | - Ludwig Eichinger
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, 50931, Cologne, Germany
| | - Rolf Schröder
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, 91054, Erlangen, Germany.
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Reactive oxygen species participate in liver function recovery during compensatory growth in zebrafish (Danio rerio). Biochem Biophys Res Commun 2018; 499:285-290. [PMID: 29574160 DOI: 10.1016/j.bbrc.2018.03.149] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 03/20/2018] [Indexed: 01/02/2023]
Abstract
Compensatory growth (CG) is defined as a phase of accelerated growth when the disadvantageous environment is improved, accompanied by metabolic adjustment. Here, we report that hepatic oxidative phosphorylation (OXPHOS) activity was enhanced during compensatory growth in zebrafish. Mitochondrial metabolism enabled the generation of reactive oxygen species (ROS), which activated the nrf2 (nuclear factor-erythroid 2-related factor 2) signaling pathway, as well as the mTOR signaling pathway. Tempol (a superoxide dismutase mimetic) treatment blocked ROS signaling in the liver as well as CG in zebrafish. These results demonstrated that mitochondrial ROS signaling are essential for the occurrence of compensatory growth in zebrafish.
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Chen MC, Hsu WL, Hwang PA, Chen YL, Chou TC. Combined administration of fucoidan ameliorates tumor and chemotherapy-induced skeletal muscle atrophy in bladder cancer-bearing mice. Oncotarget 2018; 7:51608-51618. [PMID: 27323407 PMCID: PMC5239500 DOI: 10.18632/oncotarget.9958] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 05/17/2016] [Indexed: 01/06/2023] Open
Abstract
Cancer cachexia is characterized by anorexia, skeletal muscle atrophy, and systemic inflammation. Fucoidan extracted from brown algae exhibits anti-inflammatory and anticancer activities. However, whether fucoidan ameliorates tumour and chemotherapy-induced muscle atrophy and -related cachectic symptoms remains unknown. Compared with mice with bladder cancer treated with chemotherapy alone (TGC group), those treated with a combination of low molecular weight fucoidan (LMWF) and chemotherapy drugs such as gemcitabine and cisplatin (TGCF) showed a significant reduction of body weight loss, muscle atrophy, and intestinal injury and dysfunction. Moreover, myostatin, activin A, and pro-inflammatory cytokine production, FoxO3 expression and activation, NF-κB activation, MuRF-1 and MAFbx/atrogin-1 expression, and proteasome activity in muscle were significantly decreased in the TGCF group compared with the TGC group. In addition, insulin-like growth factor 1 (IGF-1) expression and formation, and IGF-1-regulated mTOR/p70S6k/4EBP-1 protein synthesis signalling were elevated in the TGCF group compared with the TGC group. Taken together, these results suggest that LMWF is a potential agent for preventing cancer cachexia-associated muscle atrophy during chemotherapy. Furthermore, the beneficial effect of LMWF may be attributed to suppressing NF-κB-evoked inflammation, myostatin and activin A production, and subsequent muscle proteolysis, and enhancing IGF-1-dependent protein synthesis.
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Affiliation(s)
- Meng-Chuan Chen
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Wen-Lin Hsu
- School of Medicine, Tzu Chi University, Hualien, Taiwan.,Department of Radiation Oncology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Pa-An Hwang
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan
| | - Yen-Lin Chen
- Department of Pathology, Cardinal Tien Hospital, School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan
| | - Tz-Chong Chou
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.,Department of Biotechnology, Asia University, Taichung, Taiwan.,China Medical University Hospital, China Medical University, Taichung, Taiwan
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24
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Meßling S, Matthias J, Xiong Q, Fischer S, Eichinger L. The two Dictyostelium discoideum autophagy 8 proteins have distinct autophagic functions. Eur J Cell Biol 2017; 96:312-324. [PMID: 28413119 DOI: 10.1016/j.ejcb.2017.03.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/23/2017] [Accepted: 03/23/2017] [Indexed: 12/16/2022] Open
Abstract
Autophagy is a highly conserved cellular degradation pathway which is crucial for various cellular processes. The autophagic process is subdivided in the initiation, autophagosome maturation and lysosomal degradation phases and involves more than forty core and accessory autophagy-related (ATG) proteins. Autophagy 8 (ATG8, in mammals LC3) is a well-established marker of autophagy and is linked to the autophagic membrane from initiation until fusion with the lysosome. We generated single and double knock-out mutants of the two Dictyostelium paralogues, ATG8a and ATG8b, as well as strains that expressed RFP-ATG8a and/or GFP-ATG8b, RFP-ATG8b, RFP-GFP-ATG8a or RFP-GFP-ATG8b in different knock-out mutants. The ATG8b¯ mutant displayed only subtle phenotypic changes in comparison to AX2 wild-type cells. In contrast, deletion of ATG8a resulted in a complex phenotype with delayed development, reduced growth, phagocytosis and cell viability, an increase in ubiquitinylated proteins and a concomitant decrease in proteasomal activity. The phenotype of the ATG8a¯/b¯ strain was, except for cell viability, in all aforementioned aspects more severe, showing that both proteins function in parallel during most analysed cellular processes. Immunofluorescence analysis of knock-out strains expressing either RFP-GFP-ATG8a or RFP-GFP-ATG8b suggests a crucial function for ATG8b in autophagosome-lysosome fusion. Quantitative analysis of strains expressing RFP-ATG8a, RFP-ATG8b, or RFP-ATG8a and GFP-ATG8b revealed that ATG8b generally localised to small and large vesicles, whereas ATG8a preferentially co-localised with ATG8b on large vesicles, indicating that ATG8b associated with nascent autophagosomes before ATG8a, which is supported by previous results (Matthias et al., 2016). Deconvoluted confocal fluorescence images showed that ATG8b localised around ATG8a and was presumably mainly present on the outer membrane of the autophagosome while ATG8a appears to be mainly associated with the inner membrane. In summary, our data show that ATG8a and ATG8b have distinct functions and are involved in canonical as well as non-canonical autophagy. The data further suggest that ATG8b predominantly acts as adapter for the autophagy machinery at the outer and ATG8a as cargo receptor at the inner membrane of the autophagosome.
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Affiliation(s)
- Susanne Meßling
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931 Cologne, Germany
| | - Jan Matthias
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931 Cologne, Germany
| | - Qiuhong Xiong
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931 Cologne, Germany
| | - Sarah Fischer
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931 Cologne, Germany
| | - Ludwig Eichinger
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931 Cologne, Germany.
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25
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Wang ZB, Han P, Tong LC, Luo Y, Su WH, Wei X, Yu XH, Liu WY, Zhang XH, Lei H, Li ZZ, Wang F, Chen JG, Ma TH, Su DF, Li L. Low level of swiprosin-1/EFhd2 in vestibular nuclei of spontaneously hypersensitive motion sickness mice. Sci Rep 2017; 7:40986. [PMID: 28128226 PMCID: PMC5269593 DOI: 10.1038/srep40986] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 12/14/2016] [Indexed: 11/13/2022] Open
Abstract
Susceptibility to motion sickness (MS) varies considerably among humans. However, the cause of such variation is unclear. Here, we used a classical genetic approach to obtain mouse strains highly sensitive and resistant to MS (SMS and RMS). Proteomics analysis revealed substantially lower swiprosin-1 expression in SMS mouse brains. Inducing MS via rotary stimulation decreased swiprosin-1 in the mouse brains. Swiprosin-1 knockout mice were much more sensitive to motion disturbance. Immunohistochemistry revealed strong swiprosin-1 expression in the vestibular nuclei (VN). Over-expressing swiprosin-1 in the VN of SMS mice decreased MS susceptibility. Down-regulating swiprosin-1 in the VN of RMS mice by RNAi increased MS susceptibility. Additional in vivo experiments revealed decreased swiprosin-1 expression by glutamate via the NMDA receptor. Glutamate increased neuronal excitability in SMS or swiprosin-1 knockout mice more prominently than in RMS or wild-type mice. These results indicate that swiprosin-1 in the VN is a critical determinant of the susceptibility to MS.
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Affiliation(s)
- Zhi-Bin Wang
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ping Han
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ling-Chang Tong
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Yi Luo
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Wei-Heng Su
- Basal medical College, Dalian Medical University, Dalian, Liaoning 130041, China
| | - Xin Wei
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Xu-Hong Yu
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Wei-Ye Liu
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Xiu-Hua Zhang
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Hong Lei
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Zhen-Zhen Li
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Fang Wang
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Jian-Guo Chen
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Tong-Hui Ma
- Basal medical College, Dalian Medical University, Dalian, Liaoning 130041, China
| | - Ding-Feng Su
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ling Li
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
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26
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Sebastián D, Sorianello E, Segalés J, Irazoki A, Ruiz-Bonilla V, Sala D, Planet E, Berenguer-Llergo A, Muñoz JP, Sánchez-Feutrie M, Plana N, Hernández-Álvarez MI, Serrano AL, Palacín M, Zorzano A. Mfn2 deficiency links age-related sarcopenia and impaired autophagy to activation of an adaptive mitophagy pathway. EMBO J 2016; 35:1677-93. [PMID: 27334614 DOI: 10.15252/embj.201593084] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 05/27/2016] [Indexed: 01/02/2023] Open
Abstract
Mitochondrial dysfunction and accumulation of damaged mitochondria are considered major contributors to aging. However, the molecular mechanisms responsible for these mitochondrial alterations remain unknown. Here, we demonstrate that mitofusin 2 (Mfn2) plays a key role in the control of muscle mitochondrial damage. We show that aging is characterized by a progressive reduction in Mfn2 in mouse skeletal muscle and that skeletal muscle Mfn2 ablation in mice generates a gene signature linked to aging. Furthermore, analysis of muscle Mfn2-deficient mice revealed that aging-induced Mfn2 decrease underlies the age-related alterations in metabolic homeostasis and sarcopenia. Mfn2 deficiency reduced autophagy and impaired mitochondrial quality, which contributed to an exacerbated age-related mitochondrial dysfunction. Interestingly, aging-induced Mfn2 deficiency triggers a ROS-dependent adaptive signaling pathway through induction of HIF1α transcription factor and BNIP3. This pathway compensates for the loss of mitochondrial autophagy and minimizes mitochondrial damage. Our findings reveal that Mfn2 repression in muscle during aging is a determinant for the inhibition of mitophagy and accumulation of damaged mitochondria and triggers the induction of a mitochondrial quality control pathway.
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Affiliation(s)
- David Sebastián
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Eleonora Sorianello
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Jessica Segalés
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Andrea Irazoki
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Vanessa Ruiz-Bonilla
- Cell Biology Group, Department of Experimental and Health Sciences, Pompeu Fabra University (UPF) CIBER on Neurodegenerative diseases (CIBERNED), Barcelona, Spain
| | - David Sala
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Evarist Planet
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Antoni Berenguer-Llergo
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Juan Pablo Muñoz
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Manuela Sánchez-Feutrie
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Natàlia Plana
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - María Isabel Hernández-Álvarez
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Antonio L Serrano
- Cell Biology Group, Department of Experimental and Health Sciences, Pompeu Fabra University (UPF) CIBER on Neurodegenerative diseases (CIBERNED), Barcelona, Spain
| | - Manuel Palacín
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
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27
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Lv Y, Meng B, Dong H, Jing T, Wu N, Yang Y, Huang L, Moses RE, O'Malley BW, Mei B, Li X. Upregulation of GSK3β Contributes to Brain Disorders in Elderly REGγ-knockout Mice. Neuropsychopharmacology 2016; 41:1340-9. [PMID: 26370326 PMCID: PMC4793118 DOI: 10.1038/npp.2015.285] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 07/13/2015] [Accepted: 08/19/2015] [Indexed: 11/09/2022]
Abstract
GSK3β regulates some functions of the brain, but the mechanisms involved in the maintenance of GSK3β protein stability remain ambiguous. REGγ, an important proteasome activator for ubiquitin-independent protein degradation, has been shown to degrade certain intact proteins and is involved in the regulation of important biological processes. Here we demonstrate that REGγ promotes the degradation of GSK3β protein in vitro and in vivo. With increased GSK3β activity, REGγ knockout (REGγ-/-) mice exhibit late-onset sensorimotor gating and cognitive deficiencies including decreased working memory, hyperlocomotion, increased stereotype, defective prepulse inhibition (PPI), and disability in nest building, at the age of 8 months or older. Inhibition of GSK3β rescued the compromised PPI phenotypes and working memory deficiency in the knockout mice. Also, we found an age-dependent decrease in the trypsin-like proteasomal activity in REGγ-/- mice brains, which may be reflective of a lack of degradation of GSK3β. Collectively, our findings reveal a novel regulatory pathway in which the REGγ-proteasome controls the steady-state level of GSK3β protein. Dysfunction in this non-canonical proteasome degradation pathway may contribute to the sensorimotor gating deficiency and cognitive disorders in aging mice.
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Affiliation(s)
- Yiqing Lv
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai, China
| | - Bo Meng
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, China,Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200062, China, Tel: +86 21 62233970 or +86 21 62233967, Fax: +86 21 62601953, E-mail: or
| | - Hao Dong
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, China
| | - Tiantian Jing
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai, China
| | - Nan Wu
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, China
| | - Yingying Yang
- Department of Physiology and Biophysics, University of California, Irvine, CA, USA
| | - Lan Huang
- Department of Physiology and Biophysics, University of California, Irvine, CA, USA
| | - Robb E Moses
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Bert W O'Malley
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Bing Mei
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, China,Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, Shanghai 200062, China, Tel: +86 21 62233970 or +86 21 62233967, Fax: +86 21 62601953, E-mail: or
| | - Xiaotao Li
- Key Laboratory of Brain Functional Genomics, Ministry of Education, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai, China,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA, Tel: 713 7983817, Fax: 713 7901275, E-mail:
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28
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Tokuda E, Brännström T, Andersen PM, Marklund SL. Low autophagy capacity implicated in motor system vulnerability to mutant superoxide dismutase. Acta Neuropathol Commun 2016; 4:6. [PMID: 26810478 PMCID: PMC4727314 DOI: 10.1186/s40478-016-0274-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Accepted: 01/09/2016] [Indexed: 11/10/2022] Open
Abstract
Introduction The motor system is selectively vulnerable to mutations in the ubiquitously expressed aggregation-prone enzyme superoxide dismutase-1 (SOD1). Results Autophagy clears aggregates, and factors involved in the process were analyzed in multiple areas of the CNS from human control subjects (n = 10) and amyotrophic lateral sclerosis (ALS) patients (n = 18) with or without SOD1 mutations. In control subjects, the key regulatory protein Beclin 1 and downstream factors were remarkably scarce in spinal motor areas. In ALS patients, there was evidence of moderate autophagy activation and also dysregulation. These changes were largest in SOD1 mutation carriers. To explore consequences of low autophagy capacity, effects of a heterozygous deletion of Beclin 1 were examined in ALS mouse models expressing mutant SOD1s. This caused earlier SOD1 aggregation, onset of symptoms, motor neuron loss, and a markedly shortened survival. In contrast, the levels of soluble misfolded SOD1 species were reduced. Conclusions The findings suggest that an inherent low autophagy capacity might cause the vulnerability of the motor system, and that SOD1 aggregation plays a crucial role in the pathogenesis. Electronic supplementary material The online version of this article (doi:10.1186/s40478-016-0274-y) contains supplementary material, which is available to authorized users.
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29
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Xiong Q, Ünal C, Matthias J, Steinert M, Eichinger L. The phenotypes of ATG9, ATG16 and ATG9/16 knock-out mutants imply autophagy-dependent and -independent functions. Open Biol 2016; 5:150008. [PMID: 25878144 PMCID: PMC4422124 DOI: 10.1098/rsob.150008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Macroautophagy is a highly conserved intracellular bulk degradation system of all eukaryotic cells. It is governed by a large number of autophagy proteins (ATGs) and is crucial for many cellular processes. Here, we describe the phenotypes of Dictyostelium discoideum ATG16(-) and ATG9(-)/16(-) cells and compare them to the previously reported ATG9(-) mutant. ATG16 deficiency caused an increase in the expression of several core autophagy genes, among them atg9 and the two atg8 paralogues. The single and double ATG9 and ATG16 knock-out mutants had complex phenotypes and displayed severe and comparable defects in pinocytosis and phagocytosis. Uptake of Legionella pneumophila was reduced. In addition, ATG9(-) and ATG16(-) cells had dramatic defects in autophagy, development and proteasomal activity which were much more severe in the ATG9(-)/16(-) double mutant. Mutant cells showed an increase in poly-ubiquitinated proteins and contained large ubiquitin-positive protein aggregates which partially co-localized with ATG16-GFP in ATG9(-)/16(-) cells. The more severe autophagic, developmental and proteasomal phenotypes of ATG9(-)/16(-) cells imply that ATG9 and ATG16 probably function in parallel in autophagy and have in addition autophagy-independent functions in further cellular processes.
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Affiliation(s)
- Qiuhong Xiong
- Zentrum für Biochemie, Medizinische Fakultät, Universität zu Köln, Joseph-Stelzmann-Strasse 52, Köln 50931, Germany
| | - Can Ünal
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstrasse 7, Braunschweig 38106, Germany Fen Fakültesi, Türk-Alman-Üniversitesi, Istanbul 34820, Turkey
| | - Jan Matthias
- Zentrum für Biochemie, Medizinische Fakultät, Universität zu Köln, Joseph-Stelzmann-Strasse 52, Köln 50931, Germany
| | - Michael Steinert
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstrasse 7, Braunschweig 38106, Germany Helmholtz Centre for Infection Research, Braunschweig 38124, Germany
| | - Ludwig Eichinger
- Zentrum für Biochemie, Medizinische Fakultät, Universität zu Köln, Joseph-Stelzmann-Strasse 52, Köln 50931, Germany
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Papaevgeniou N, Chondrogianni N. UPS Activation in the Battle Against Aging and Aggregation-Related Diseases: An Extended Review. Methods Mol Biol 2016; 1449:1-70. [PMID: 27613027 DOI: 10.1007/978-1-4939-3756-1_1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Aging is a biological process accompanied by gradual increase of damage in all cellular macromolecules, i.e., nucleic acids, lipids, and proteins. When the proteostasis network (chaperones and proteolytic systems) cannot reverse the damage load due to its excess as compared to cellular repair/regeneration capacity, failure of homeostasis is established. This failure is a major hallmark of aging and/or aggregation-related diseases. Dysfunction of the major cellular proteolytic machineries, namely the proteasome and the lysosome, has been reported during the progression of aging and aggregation-prone diseases. Therefore, activation of these pathways is considered as a possible preventive or therapeutic approach against the progression of these processes. This chapter focuses on UPS activation studies in cellular and organismal models and the effects of such activation on aging, longevity and disease prevention or reversal.
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Affiliation(s)
- Nikoletta Papaevgeniou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens, 11635, Greece
| | - Niki Chondrogianni
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Ave., Athens, 11635, Greece.
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31
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Chen MC, Chen YL, Lee CF, Hung CH, Chou TC. Supplementation of Magnolol Attenuates Skeletal Muscle Atrophy in Bladder Cancer-Bearing Mice Undergoing Chemotherapy via Suppression of FoxO3 Activation and Induction of IGF-1. PLoS One 2015; 10:e0143594. [PMID: 26600425 PMCID: PMC4657971 DOI: 10.1371/journal.pone.0143594] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 11/06/2015] [Indexed: 12/20/2022] Open
Abstract
Skeletal muscle atrophy, the most prominent phenotypic feature of cancer cachexia, is often observed in cancer patients undergoing chemotherapy. Magnolol (M) extracted from Magnolia officinalis exhibits several pharmacological effects including anti-inflammatory and anticancer activities. In this study, we investigated whether magnolol supplementation protects against the development of cachexia symptoms in bladder cancer-bearing mice undergoing chemotherapy. Combined treatment of magnolol with chemotherapeutic drugs, such as gemcitabine and cisplatin (TGCM) or gemcitabine (TGM), markedly attenuates the body weight loss and skeletal muscle atrophy compared with conventional chemotherapy (TGC). The antiatrophic effect of magnolol may be associated with inhibition of myostatin and activin A formation, as well as FoxO3 transcriptional activity resulting from Akt activation, thereby suppressing ubiquitin ligases MuRF-1 and MAFbx/atrogin-1 expression, as well as proteasomal enzyme activity. Notably, magnolol-induced insulin-like growth factor 1 (IGF-1) production and related protein synthesis may also contribute to its protective effects. The decreased food intake, and intestinal injury and dysfunction observed in the mice of TGC group were significantly improved in the TGCM and TGM groups. Moreover, the increased inflammatory responses evidenced by elevation of proinflammatory cytokine formation and NF-κB activation occurred in the atrophying muscle of TGC group were markedly inhibited in mice of combined treatment with magnolol. In summary, these findings support that magnolol is a promising chemopreventive supplement for preventing chemotherapy-induced skeletal muscle atrophy associated with cancer cachexia by suppressing muscle protein degradation, and inflammatory responses, as well as increasing IGF-1-mediated protein synthesis.
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Affiliation(s)
- Meng-Chuan Chen
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Yen-Lin Chen
- Department of Pathology, Cardinal Tien Hospital; School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan
| | - Chi-Feng Lee
- Division of Biopharmaceuticals, Institute of Preventive Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Chih-Huang Hung
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan
| | - Tz-Chong Chou
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan
- Department of Biotechnology, Asia University, Taichung, Taiwan
- China Medical University Hospital, China Medical University, Taichung, Taiwan
- * E-mail:
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32
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O'Brien MA, Moravec RA, Riss TL, Bulleit RF. Homogeneous, bioluminescent proteasome assays. Methods Mol Biol 2015; 1219:95-114. [PMID: 25308265 DOI: 10.1007/978-1-4939-1661-0_9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Protein degradation is mediated predominantly through the ubiquitin-proteasome pathway. The importance of the proteasome in regulating degradation of proteins involved in cell-cycle control, apoptosis, and angiogenesis led to the recognition of the proteasome as a therapeutic target for cancer. The proteasome is also essential for degrading misfolded and aberrant proteins, and impaired proteasome function has been implicated in neurodegerative and cardiovascular diseases. Robust, sensitive assays are essential for monitoring proteasome activity and for developing inhibitors of the proteasome. Peptide-conjugated fluorophores are widely used as substrates for monitoring proteasome activity, but fluorogenic substrates can exhibit significant background and can be problematic for screening because of cellular autofluorescence or interference from fluorescent library compounds. Furthermore, fluorescent proteasome assays require column-purified 20S or 26S proteasome (typically obtained from erythrocytes), or proteasome extracts from whole cells, as their samples. To provide assays more amenable to high-throughput screening, we developed a homogeneous, bioluminescent method that combines peptide-conjugated aminoluciferin substrates and a stabilized luciferase. Using substrates for the chymotrypsin-like, trypsin-like, and caspase-like proteasome activities in combination with a selective membrane permeabilization step, we developed single-step, cell-based assays to measure each of the proteasome catalytic activities. The homogeneous method eliminates the need to prepare individual cell extracts as samples and has adequate sensitivity for 96- and 384-well plates. The simple "add and read" format enables sensitive and rapid proteasome assays ideal for inhibitor screening.
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Affiliation(s)
- Martha A O'Brien
- Promega Corporation, 2800 Woods Hollow Road, Madison, WI, 53711, USA,
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Han MHJ, Hu Z, Chen CY, Chen Y, Gucek M, Li Z, Markey SP. Dysbindin-associated proteome in the p2 synaptosome fraction of mouse brain. J Proteome Res 2014; 13:4567-80. [PMID: 25198678 PMCID: PMC4227559 DOI: 10.1021/pr500656z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
![]()
The
gene DTNBP1 encodes the protein dysbindin and is among the
most promising and highly investigated schizophrenia-risk genes. Accumulating
evidence suggests that dysbindin plays an important role in the regulation
of neuroplasticity. Dysbindin was reported to be a stable component
of BLOC-1 complex in the cytosol. However, little is known about the
endogenous dysbindin-containing complex in the brain synaptosome.
In this study, we investigated the associated proteome of dysbindin
in the P2 synaptosome fraction of mouse brain. Our data suggest that
dysbindin has three isoforms associating with different complexes
in the P2 fraction of mouse brain. To facilitate immunopurification,
BAC transgenic mice expressing a tagged dysbindin were generated,
and 47 putative dysbindin-associated proteins, including all components
of BLOC-1, were identified by mass spectrometry in the dysbindin-containing
complex purified from P2. The interactions of several selected candidates,
including WDR11, FAM91A1, snapin, muted, pallidin, and two proteasome
subunits, PSMD9 and PSMA4, were verified by coimmunoprecipitation.
The specific proteasomal activity is significantly reduced in the
P2 fraction of the brains of the dysbindin-null mutant (sandy) mice.
Our data suggest that dysbindin is functionally interrelated to the
ubiquitin-proteasome system and offer a molecular repertoire for future
study of dysbindin functional networks in brain.
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Affiliation(s)
- Meng-Hsuan J Han
- National Institute of Mental Health , Bethesda, Maryland 20892, United States
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Azakir BA, Erne B, Di Fulvio S, Stirnimann G, Sinnreich M. Proteasome inhibitors increase missense mutated dysferlin in patients with muscular dystrophy. Sci Transl Med 2014; 6:250ra112. [DOI: 10.1126/scitranslmed.3009612] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Hwee DT, Baehr LM, Philp A, Baar K, Bodine SC. Maintenance of muscle mass and load-induced growth in Muscle RING Finger 1 null mice with age. Aging Cell 2014; 13:92-101. [PMID: 23941502 PMCID: PMC3947038 DOI: 10.1111/acel.12150] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2013] [Indexed: 12/18/2022] Open
Abstract
Age-related loss of muscle mass occurs to varying degrees in all individuals and has a detrimental effect on morbidity and mortality. Muscle RING Finger 1 (MuRF1), a muscle-specific E3 ubiquitin ligase, is believed to mediate muscle atrophy through the ubiquitin proteasome system (UPS). Deletion of MuRF1 (KO) in mice attenuates the loss of muscle mass following denervation, disuse, and glucocorticoid treatment; however, its role in age-related muscle loss is unknown. In this study, skeletal muscle from male wild-type (WT) and MuRF1 KO mice was studied up to the age of 24 months. Muscle mass and fiber cross-sectional area decreased significantly with age in WT, but not in KO mice. In aged WT muscle, significant decreases in proteasome activities, especially 20S and 26S β5 (20–40% decrease), were measured and were associated with significant increases in the maladaptive endoplasmic reticulum (ER) stress marker, CHOP. Conversely, in aged MuRF1 KO mice, 20S or 26S β5 proteasome activity was maintained or decreased to a lesser extent than in WT mice, and no increase in CHOP expression was measured. Examination of the growth response of older (18 months) mice to functional overload revealed that old WT mice had significantly less growth relative to young mice (1.37- vs. 1.83-fold), whereas old MuRF1 KO mice had a normal growth response (1.74- vs. 1.90-fold). These data collectively suggest that with age, MuRF1 plays an important role in the control of skeletal muscle mass and growth capacity through the regulation of cellular stress.
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Affiliation(s)
- Darren T. Hwee
- Departments of Neurobiology, Physiology, and Behavior; University of California Davis; Davis CA 95616 USA
- Molecular, Cellular and Integrative Physiology Graduate Group; University of California Davis; Davis CA 95616 USA
| | - Leslie M. Baehr
- Physiology and Membrane Biology; University of California Davis; Davis CA 95616 USA
| | - Andrew Philp
- Departments of Neurobiology, Physiology, and Behavior; University of California Davis; Davis CA 95616 USA
| | - Keith Baar
- Departments of Neurobiology, Physiology, and Behavior; University of California Davis; Davis CA 95616 USA
- Physiology and Membrane Biology; University of California Davis; Davis CA 95616 USA
| | - Sue C. Bodine
- Departments of Neurobiology, Physiology, and Behavior; University of California Davis; Davis CA 95616 USA
- Physiology and Membrane Biology; University of California Davis; Davis CA 95616 USA
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36
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Kemp CM, Oliver WT, Wheeler TL, Chishti AH, Koohmaraie M. The effects of Capn1 gene inactivation on skeletal muscle growth, development, and atrophy, and the compensatory role of other proteolytic systems. J Anim Sci 2013; 91:3155-67. [PMID: 23798514 PMCID: PMC3962768 DOI: 10.2527/jas.2012-5737] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Myofibrillar protein turnover is a key component of muscle growth and degeneration, requiring proteolytic enzymes to degrade the skeletal muscle proteins. The objective of this study was to investigate the role of the calpain proteolytic system in muscle growth development using μ-calpain knockout (KO) mice in comparison with control wild-type (WT) mice, and evaluate the subsequent effects of silencing this gene on other proteolytic systems. No differences in muscle development between genotypes were observed during the early stages of growth due to the up regulation of other proteolytic systems. The KO mice showed significantly greater m-calpain protein abundance (P < 0.01) and activity (P < 0.001), and greater caspase 3/7 activity (P < 0.05). At 30 wk of age, KO mice showed increased protein:DNA (P < 0.05) and RNA:DNA ratios (P < 0.01), greater protein content (P < 0.01) at the expense of lipid deposition (P < 0.05), and an increase in size and number of fast-twitch glycolytic muscle fibers (P < 0.05), suggesting that KO mice exhibit an increased capacity to accumulate and maintain protein in their skeletal muscle. Also, expression of proteins associated with muscle regeneration (neural cell adhesion molecule and myoD) were both reduced in the mature KO mice (P < 0.05 and P < 0.01, respectively), indicating less muscle regeneration and, therefore, less muscle damage. These findings indicate the concerted action of proteolytic systems to ensure muscle protein homeostasis in vivo. Furthermore, these data contribute to the existing evidence of the importance of the calpain system's involvement in muscle growth, development, and atrophy. Collectively, these data suggest that there are opportunities to target the calpain system to promote the growth and/or restoration of skeletal muscle mass.
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Affiliation(s)
- C. M. Kemp
- USDA, ARS, U.S. Meat Animal Research Center, Clay Center, NE 68933
| | - W. T. Oliver
- USDA, ARS, U.S. Meat Animal Research Center, Clay Center, NE 68933
| | - T. L. Wheeler
- USDA, ARS, U.S. Meat Animal Research Center, Clay Center, NE 68933
| | - A. H. Chishti
- Department of Molecular Physiology and Pharmacology, Tufts University, School of Medicine, Boston, MA 02111
| | - M. Koohmaraie
- IEH Laboratories & Consulting Group, Lake Forest Park, WA 98155; and College of Food and Agriculture, King Saud University, Riyadh, Saudi Arabia
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Greussing R, Unterluggauer H, Koziel R, Maier AB, Jansen-Dürr P. Monitoring of ubiquitin-proteasome activity in living cells using a Degron (dgn)-destabilized green fluorescent protein (GFP)-based reporter protein. J Vis Exp 2012:3327. [PMID: 23169445 DOI: 10.3791/3327] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Proteasome is the main intracellular organelle involved in the proteolytic degradation of abnormal, misfolded, damaged or oxidized proteins (1, 2). Maintenance of proteasome activity was implicated in many key cellular processes, like cell's stress response (3), cell cycle regulation and cellular differentiation (4) or in immune system response (5). The dysfunction of the ubiquitin-proteasome system has been related to the development of tumors and neurodegenerative diseases (4, 6). Additionally, a decrease in proteasome activity was found as a feature of cellular senescence and organismal aging (7, 8, 9, 10). Here, we present a method to measure ubiquitin-proteasome activity in living cells using a GFP-dgn fusion protein. To be able to monitor ubiquitin-proteasome activity in living primary cells, complementary DNA constructs coding for a green fluorescent protein (GFP)-dgn fusion protein (GFP-dgn, unstable) and a variant carrying a frameshift mutation (GFP-dgnFS, stable (11)) are inserted in lentiviral expression vectors. We prefer this technique over traditional transfection techniques because it guarantees a very high transfection efficiency independent of the cell type or the age of the donor. The difference between fluorescence displayed by the GFP-dgnFS (stable) protein and the destabilized protein (GFP-dgn) in the absence or presence of proteasome inhibitor can be used to estimate ubiquitin-proteasome activity in each particular cell strain. These differences can be monitored by epifluorescence microscopy or can be measured by flow cytometry.
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Affiliation(s)
- Ruth Greussing
- Molecular and Cell Biology, Institute for Biomedical Aging Research
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Arhzaouy K, Strucksberg KH, Tung SM, Tangavelou K, Stumpf M, Faix J, Schröder R, Clemen CS, Eichinger L. Heteromeric p97/p97R155C complexes induce dominant negative changes in wild-type and autophagy 9-deficient Dictyostelium strains. PLoS One 2012; 7:e46879. [PMID: 23056506 PMCID: PMC3463532 DOI: 10.1371/journal.pone.0046879] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 09/06/2012] [Indexed: 11/19/2022] Open
Abstract
Heterozygous mutations in the human VCP (p97) gene cause autosomal-dominant IBMPFD (inclusion body myopathy with early onset Paget's disease of bone and frontotemporal dementia), ALS14 (amyotrophic lateral sclerosis with or without frontotemporal dementia) and HSP (hereditary spastic paraplegia). Most prevalent is the R155C point mutation. We studied the function of p97 in the social amoeba Dictyostelium discoideum and have generated strains that ectopically express wild-type (p97) or mutant p97 (p97(R155C)) fused to RFP in AX2 wild-type and autophagy 9 knock-out (ATG9(KO)) cells. Native gel electrophoresis showed that both p97 and p97(R155C) assemble into hexamers. Co-immunoprecipitation studies revealed that endogenous p97 and p97(R155C)-RFP form heteromers. The mutant strains displayed changes in cell growth, phototaxis, development, proteasomal activity, ubiquitinylated proteins, and ATG8(LC3) indicating mis-regulation of multiple essential cellular processes. Additionally, immunofluorescence analysis revealed an increase of protein aggregates in ATG9(KO)/p97(R155C)-RFP and ATG9(KO) cells. They were positive for ubiquitin in both strains, however, solely immunoreactive for p97 in the ATG9(KO) mutant. A major finding is that the expression of p97(R155C)-RFP in the ATG9(KO) strain partially or fully rescued the pleiotropic phenotype. We also observed dose-dependent effects of p97 on several cellular processes. Based on findings in the single versus the double mutants we propose a novel mode of p97 interaction with the core autophagy protein ATG9 which is based on mutual inhibition.
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Affiliation(s)
- Khalid Arhzaouy
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - Karl-Heinz Strucksberg
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Sze Man Tung
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | | | - Maria Stumpf
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Rolf Schröder
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Christoph S. Clemen
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - Ludwig Eichinger
- Intitute for Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
- * E-mail:
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Skeletal muscle mitochondria and aging: a review. J Aging Res 2012; 2012:194821. [PMID: 22888430 PMCID: PMC3408651 DOI: 10.1155/2012/194821] [Citation(s) in RCA: 196] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Accepted: 05/21/2012] [Indexed: 12/12/2022] Open
Abstract
Aging is characterized by a progressive loss of muscle mass and muscle strength. Declines in skeletal muscle mitochondria are thought to play a primary role in this process. Mitochondria are the major producers of reactive oxygen species, which damage DNA, proteins, and lipids if not rapidly quenched. Animal and human studies typically show that skeletal muscle mitochondria are altered with aging, including increased mutations in mitochondrial DNA, decreased activity of some mitochondrial enzymes, altered respiration with reduced maximal capacity at least in sedentary individuals, and reduced total mitochondrial content with increased morphological changes. However, there has been much controversy over measurements of mitochondrial energy production, which may largely be explained by differences in approach and by whether physical activity is controlled for. These changes may in turn alter mitochondrial dynamics, such as fusion and fission rates, and mitochondrially induced apoptosis, which may also lead to net muscle fiber loss and age-related sarcopenia. Fortunately, strategies such as exercise and caloric restriction that reduce oxidative damage also improve mitochondrial function. While these strategies may not completely prevent the primary effects of aging, they may help to attenuate the rate of decline.
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da Cunha FM, Demasi M, Kowaltowski AJ. Aging and calorie restriction modulate yeast redox state, oxidized protein removal, and the ubiquitin-proteasome system. Free Radic Biol Med 2011; 51:664-70. [PMID: 21684330 DOI: 10.1016/j.freeradbiomed.2011.05.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 05/12/2011] [Accepted: 05/24/2011] [Indexed: 12/21/2022]
Abstract
The ubiquitin-proteasome system governs the half-life of most cellular proteins. Calorie restriction (CR) extends the maximum life span of a variety of species and prevents oxidized protein accumulation. We studied the effects of CR on the ubiquitin-proteasome system and protein turnover in aging Saccharomyces cerevisiae. CR increased chronological life span as well as proteasome activity compared to control cells. The levels of protein carbonyls, a marker of protein oxidation, and those of polyubiquitinated proteins were modulated by CR. Controls, but not CR cells, exhibited a significant increase in oxidized proteins. In keeping with decreased proteasome activity, polyubiquitinated proteins were increased in young control cells compared to time-matched CR cells, but were profoundly decreased in aged control cells despite decreased proteasomal activity. This finding is related to a decreased polyubiquitination ability due to the impairment of the ubiquitin-activating enzyme in aged control cells, probably related to a more oxidative microenvironment. CR preserves the ubiquitin-proteasome system activity. Overall, we found that aging and CR modulate many aspects of protein modification and turnover.
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Affiliation(s)
- Fernanda Marques da Cunha
- Departamento de Bioquímica, Universidade de São Paulo, 05508-900 Cidade Universitária, São Paulo, Brazil
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41
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Onesto E, Rusmini P, Crippa V, Ferri N, Zito A, Galbiati M, Poletti A. Muscle cells and motoneurons differentially remove mutant SOD1 causing familial amyotrophic lateral sclerosis. J Neurochem 2011; 118:266-80. [PMID: 21554318 PMCID: PMC3206220 DOI: 10.1111/j.1471-4159.2011.07298.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal motoneuronal disease which occurs in sporadic or familial forms, clinically indistinguishable. About 15% of familial ALS cases are linked to mutations of the superoxide dismutase 1 (SOD1) gene that may induce misfolding in the coded protein, exerting neurotoxicity to motoneurons. However, other cell types might be target of SOD1 toxicity, because muscle-restricted expression of mutant SOD1 correlates with muscle atrophy and motoneurons death. We analysed the molecular behaviour of mutant SOD1 in motoneuronal NSC34 and muscle C2C12 cells. We found that misfolded mutant SOD1 clearance is much more efficient in muscle C2C12 than in motoneuronal NSC34 cells. Mutant SOD1 forms aggregates and impairs the proteasome only in motoneuronal NSC34 cells. Interestingly, NSC34 cells expressing mutant SOD1 are more sensitive to a superoxide-induced oxidative stress. Moreover, in muscle C2C12 cells mutant SOD1 remains soluble even when proteasome is inhibited with MG132. The higher mutant SOD1 clearance in muscle cells correlates with a more efficient proteasome activity, combined with a robust autophagy activation. Therefore, muscle cells seem to better manage misfolded SOD1 species, not because of an intrinsic property of the mutant protein, but in function of the cell environment, indicating also that the SOD1 toxicity at muscle level may not directly depend on its aggregation rate.
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Affiliation(s)
- Elisa Onesto
- Dipartimento di Endocrinologia, Fisiopatologia e Biologia Applicata, Università degli Studi di Milano, Milano, Italy
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Kozieł R, Greussing R, Maier AB, Declercq L, Jansen-Dürr P. Functional interplay between mitochondrial and proteasome activity in skin aging. J Invest Dermatol 2010; 131:594-603. [PMID: 21191400 DOI: 10.1038/jid.2010.383] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
According to the mitochondrial theory of aging, reactive oxygen species (ROS) derived primarily from mitochondria cause cumulative oxidative damage to various cellular molecules and thereby contribute to the aging process. On the other hand, a pivotal role of the proteasome, as a main proteolytic system implicated in the degradation of oxidized proteins during aging, is suggested. In this study, we analyzed mitochondrial function in dermal fibroblasts derived from biopsies obtained from healthy young, middle-aged, and old donors. We also determined proteasome activity in these cells, using a degron-destabilized green fluorescent protein (GFP)-based reporter protein. We found a significant decrease in mitochondrial membrane potential in samples from aged donors, accompanied by a significant increase in ROS levels. Respiratory activity was not significantly altered with donor age, probably reflecting genetic variation. Proteasome activity was significantly decreased in fibroblasts from middle-aged donors compared with young donors; fibroblasts derived from the oldest donors displayed a high heterogeneity in this assay. We also found intraindividual coregulation of mitochondrial and proteasomal activities in all human fibroblast strains tested, suggesting that both systems are interdependent. Accordingly, pharmacological inhibition of the proteasome led to decreased mitochondrial function, whereas inhibition of mitochondrial function in turn reduced proteasome activity.
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Affiliation(s)
- Rafał Kozieł
- Institute for Biomedical Aging Research, Austrian Academy of Sciences, Innsbruck, Austria
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