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Uenaka E, Ojima K, Suzuki T, Kobayashi K, Muroya S, Nishimura T. Murf1 alters myosin replacement rates in cultured myotubes in a myosin isoform-dependent manner. In Vitro Cell Dev Biol Anim 2024:10.1007/s11626-024-00916-0. [PMID: 38758432 DOI: 10.1007/s11626-024-00916-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 04/23/2024] [Indexed: 05/18/2024]
Abstract
Skeletal muscle tissue increases or decreases its volume by synthesizing or degrading myofibrillar proteins. The ubiquitin-proteasome system plays a pivotal role during muscle atrophy, where muscle ring finger proteins (Murf) function as E3 ubiquitin ligases responsible for identifying and targeting substrates for degradation. Our previous study demonstrated that overexpression of Ozz, an E3 specific to embryonic myosin heavy chain (Myh3), precisely reduced the Myh3 replacement rate in the thick filaments of myotubes (E. Ichimura et al., Physiol Rep. 9:e15003, 2021). These findings strongly suggest that E3 plays a critical role in regulating myosin replacement. Here, we hypothesized that the Murf isoforms, which recognize Myhs as substrates, reduced the myosin replacement rates through the enhanced Myh degradation by Murfs. First, fluorescence recovery after a photobleaching experiment was conducted to assess whether Murf isoforms affected the GFP-Myh3 replacement. In contrast to Murf2 or Murf3 overexpression, Murf1 overexpression selectively facilitated the GFP-Myh3 myosin replacement. Next, to examine the effects of Murf1 overexpression on the replacement of myosin isoforms, Cherry-Murf1 was coexpressed with GFP-Myh1, GFP-Myh4, or GFP-Myh7 in myotubes. Intriguingly, Murf1 overexpression enhanced the myosin replacement of GFP-Myh4 but did not affect those of GFP-Myh1 or GFP-Myh7. Surprisingly, overexpression of Murf1 did not enhance the ubiquitination of proteins. These results indicate that Murf1 selectively regulated myosin replacement in a Myh isoform-dependent fashion, independent of enhanced ubiquitination. This suggests that Murf1 may have a role beyond functioning as a ubiquitin ligase E3 in thick filament myosin replacement.
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Affiliation(s)
- Emi Uenaka
- Research Faculty of Agriculture, Graduate School of Agriculture, Hokkaido University, 9 Kita, 9 Nishi, Sapporo, Hokkaido, 060-8589, Japan
- Space Environment and Energy Laboratories, Nippon Telegraph and Telephone Corporation, Musashino, Tokyo, 180-8585, Japan
| | - Koichi Ojima
- Muscle Biology Research Unit, Division of Animal Products Research, Institute of Livestock and Grassland Science, NARO, 2 Ikenodai, Tsukuba, Ibaraki, 305-0901, Japan
| | - Takahiro Suzuki
- Laboratory of Muscle and Meat Science, Department of Animal and Marine Bioresource Sciences, Faculty of Agriculture, Graduate School of Agriculture, Kyushu University, Motooka 744, Nishi-Ku, Fukuoka, 819-0395, Japan
| | - Ken Kobayashi
- Research Faculty of Agriculture, Graduate School of Agriculture, Hokkaido University, 9 Kita, 9 Nishi, Sapporo, Hokkaido, 060-8589, Japan
| | - Susumu Muroya
- Muscle Biology Research Unit, Division of Animal Products Research, Institute of Livestock and Grassland Science, NARO, 2 Ikenodai, Tsukuba, Ibaraki, 305-0901, Japan
- Laboratory of Meat Science and Production, Faculty of Veterinary Medicine, Kagoshima University, 1-21-24, Korimoto, Kagoshima, 890-0065, Japan
| | - Takanori Nishimura
- Research Faculty of Agriculture, Graduate School of Agriculture, Hokkaido University, 9 Kita, 9 Nishi, Sapporo, Hokkaido, 060-8589, Japan.
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2
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Lord SO, Dawson PW, Chunthorng-Orn J, Ng J, Baehr LM, Hughes DC, Sridhar P, Knowles T, Bodine SC, Lai YC. Uncovering the mechanisms of MuRF1-induced ubiquitylation and revealing similarities with MuRF2 and MuRF3. Biochem Biophys Rep 2024; 37:101636. [PMID: 38283190 PMCID: PMC10818185 DOI: 10.1016/j.bbrep.2023.101636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/12/2023] [Accepted: 12/29/2023] [Indexed: 01/30/2024] Open
Abstract
MuRF1 (Muscle-specific RING finger protein 1; gene name TRIM63) is a ubiquitin E3 ligase, associated with the progression of muscle atrophy. As a RING (Really Interesting New Gene) type E3 ligase, its unique activity of ubiquitylation is driven by a specific interaction with a UBE2 (ubiquitin conjugating enzyme). Our understanding of MuRF1 function remains unclear as candidate UBE2s have not been fully elucidated. In the present study, we screened human ubiquitin dependent UBE2s in vitro and found that MuRF1 engages in ubiquitylation with UBE2D, UBE2E, UBE2N/V families and UBE2W. MuRF1 can cause mono-ubiquitylation, K48- and K63-linked polyubiquitin chains in a UBE2 dependent manner. Moreover, we identified a two-step UBE2 dependent mechanism whereby MuRF1 is monoubiquitylated by UBE2W which acts as an anchor for UBE2N/V to generate polyubiquitin chains. With the in vitro ubiquitylation assay, we also found that MuRF2 and MuRF3 not only share the same UBE2 partners as MuRF1 but can also directly ubiquitylate the same substrates: Titin (A168-A170), Desmin, and MYLPF (Myosin Light Chain, Phosphorylatable, Fast Skeletal Muscle; also called Myosin Light Regulatory Chain 2). In summary, our work presents new insights into the mechanisms that underpin MuRF1 activity and reveals overlap in MuRF-induced ubiquitylation which could explain their partial redundancy in vivo.
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Affiliation(s)
- Samuel O. Lord
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Peter W.J. Dawson
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, UK
| | | | - Jimi Ng
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Leslie M. Baehr
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - David C. Hughes
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Pooja Sridhar
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Timothy Knowles
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Sue C. Bodine
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Yu-Chiang Lai
- School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, UK
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Hughes DC, Goodman CA, Baehr LM, Gregorevic P, Bodine SC. A critical discussion on the relationship between E3 ubiquitin ligases, protein degradation, and skeletal muscle wasting: it's not that simple. Am J Physiol Cell Physiol 2023; 325:C1567-C1582. [PMID: 37955121 PMCID: PMC10861180 DOI: 10.1152/ajpcell.00457.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/07/2023] [Accepted: 11/07/2023] [Indexed: 11/14/2023]
Abstract
Ubiquitination is an important post-translational modification (PTM) for protein substrates, whereby ubiquitin is added to proteins through the coordinated activity of activating (E1), ubiquitin-conjugating (E2), and ubiquitin ligase (E3) enzymes. The E3s provide key functions in the recognition of specific protein substrates to be ubiquitinated and aid in determining their proteolytic or nonproteolytic fates, which has led to their study as indicators of altered cellular processes. MuRF1 and MAFbx/Atrogin-1 were two of the first E3 ubiquitin ligases identified as being upregulated in a range of different skeletal muscle atrophy models. Since their discovery, the expression of these E3 ubiquitin ligases has often been studied as a surrogate measure of changes to bulk protein degradation rates. However, emerging evidence has highlighted the dynamic and complex regulation of the ubiquitin proteasome system (UPS) in skeletal muscle and demonstrated that protein ubiquitination is not necessarily equivalent to protein degradation. These observations highlight the potential challenges of quantifying E3 ubiquitin ligases as markers of protein degradation rates or ubiquitin proteasome system (UPS) activation. This perspective examines the usefulness of monitoring E3 ubiquitin ligases for determining specific or bulk protein degradation rates in the settings of skeletal muscle atrophy. Specific questions that remain unanswered within the skeletal muscle atrophy field are also identified, to encourage the pursuit of new research that will be critical in moving forward our understanding of the molecular mechanisms that govern protein function and degradation in muscle.
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Affiliation(s)
- David C Hughes
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Craig A Goodman
- Centre for Muscle Research (CMR), Department of Anatomy and Physiology, The University of Melbourne, Parkville, Victoria, Australia
| | - Leslie M Baehr
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Paul Gregorevic
- Centre for Muscle Research (CMR), Department of Anatomy and Physiology, The University of Melbourne, Parkville, Victoria, Australia
- Department of Neurology, The University of Washington School of Medicine, Seattle, Washington, United States
| | - Sue C Bodine
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
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Ferreira RP, Duarte JA. Protein Turnover in Skeletal Muscle: Looking at Molecular Regulation towards an Active Lifestyle. Int J Sports Med 2023; 44:763-777. [PMID: 36854391 DOI: 10.1055/a-2044-8277] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Skeletal muscle is a highly plastic tissue, able to change its mass and functional properties in response to several stimuli. Skeletal muscle mass is influenced by the balance between protein synthesis and breakdown, which is regulated by several signaling pathways. The relative contribution of Akt/mTOR signaling, ubiquitin-proteasome pathway, autophagy among other signaling pathways to protein turnover and, therefore, to skeletal muscle mass, differs depending on the wasting or loading condition and muscle type. By modulating mitochondria biogenesis, PGC-1α has a major role in the cell's bioenergetic status and, thus, on protein turnover. In fact, rates of protein turnover regulate differently the levels of distinct protein classes in response to atrophic or hypertrophic stimuli. Mitochondrial protein turnover rates may be enhanced in wasting conditions, whereas the increased turnover of myofibrillar proteins triggers muscle mass gain. The present review aims to update the knowledge on the molecular pathways implicated in the regulation of protein turnover in skeletal muscle, focusing on how distinct muscle proteins may be modulated by lifestyle interventions with emphasis on exercise training. The comprehensive analysis of the anabolic effects of exercise programs will pave the way to the tailored management of muscle wasting conditions.
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Affiliation(s)
- Rita Pinho Ferreira
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Jose Alberto Duarte
- TOXRUN - Toxicology Research Unit, University Institute of Health Sciences, CESPU, CRL, Gandra, Portugal
- CIAFEL, Faculty of Sports, University of Porto and Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal
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Wang S, Wang L, Gu S, Han Y, Li L, Jia Z, Gao N, Liu Y, Lin S, Hou Y, Wang X, Mao J. Effect of optimized new Shengmai powder on exercise tolerance in rats with heart failure by regulating the ubiquitin-proteasome signaling pathway. Front Cardiovasc Med 2023; 10:1168341. [PMID: 37288261 PMCID: PMC10242132 DOI: 10.3389/fcvm.2023.1168341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/24/2023] [Indexed: 06/09/2023] Open
Abstract
Introduction Decreased exercise tolerance is a common symptom in patients with heart failure, which is closely related to protein degradation and apoptosis regulated by the ubiquitin-proteasome signaling (UPS) pathway. In this study, the effect of Chinese medicine, optimized new Shengmai powder, on exercise tolerance in rats with heart failure was investigated via the UPS pathway. Methods The heart failure model was prepared by ligating the left anterior descending branch of the coronary artery in rats, in which the sham-operated group was only threaded and not ligated. Rats (left ventricular ejection fraction ≤ 45%) were randomly divided into the following groups: model group, YHXSMS group, Benazepril group, and proteasome inhibitor Oprozomib group, and they were administered the corresponding drugs by gavage for 4 weeks. The cardiac function of rats was evaluated by performing an echocardiography examination and a hemodynamic test and the exercise tolerance was done by conducting an exhaustive swimming test. The mechanism was revealed by TUNEL detection, immunohistochemistry, immunofluorescence analysis, Western blot, and quantitative real-time PCR. Results The study showed that there was a decrease in cardiac function and exercise tolerance of rats in the model group and also destruction of cardiac and skeletal muscle fibers, a proliferation of collagen tissue, and an increment of apoptosis. Our study suggested that optimized new Shengmai powder could exert antiapoptotic effects on myocardial and skeletal muscle cells and improve myocardial contractility and exercise tolerance by inhibiting the overactivation of the UPS pathway, downregulating MAFbx, and Murf-1 overexpression, inhibiting the activation of the JNK signaling pathway, upregulating bcl-2 expression, and decreasing bax and caspase-3 levels. Conclusions The study showed that the optimized new Shengmai powder could improve cardiac function and exercise tolerance in rats with heart failure through the UPS pathway.
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Affiliation(s)
- Shuai Wang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Lin Wang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
- Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Shaoke Gu
- Department of Geratology, Shijiazhuang Hospital of Traditional Chinese Medicine, He Bei, China
| | - Yixiao Han
- Department of Cardiology, ShenZhen Traditional Chinese Medicine Hospital, Shen Zhen, China
| | - Linfeng Li
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
- Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Zhuangzhuang Jia
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Ning Gao
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
- Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yu Liu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Shanshan Lin
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
- Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yazhu Hou
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Xianliang Wang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Jingyuan Mao
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
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6
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Linke WA. Stretching the story of titin and muscle function. J Biomech 2023; 152:111553. [PMID: 36989971 DOI: 10.1016/j.jbiomech.2023.111553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/29/2023]
Abstract
The discovery of the giant protein titin, also known as connectin, dates almost half a century back. In this review, I recapitulate major advances in the discovery of the titin filaments and the recognition of their properties and function until today. I briefly discuss how our understanding of the layout and interactions of titin in muscle sarcomeres has evolved and review key facts about the titin sequence at the gene (TTN) and protein levels. I also touch upon properties of titin important for the stability of the contractile units and the assembly and maintenance of sarcomeric proteins. The greater part of my discussion centers around the mechanical function of titin in skeletal muscle. I cover milestones of research on titin's role in stretch-dependent passive tension development, recollect the reasons behind the enormous elastic diversity of titin, and provide an update on the molecular mechanisms of titin elasticity, details of which are emerging even now. I reflect on current knowledge of how muscle fibers behave mechanically if titin stiffness is removed and how titin stiffness can be dynamically regulated, such as by posttranslational modifications or calcium binding. Finally, I highlight novel and exciting, but still controversially discussed, insight into the role titin plays in active tension development, such as length-dependent activation and contraction from longer muscle lengths.
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Affiliation(s)
- Wolfgang A Linke
- Institute of Physiology II, University of Münster, Germany; Clinic for Cardiology and Pneumology, University Medical Center Göttingen, Germany; German Centre for Cardiovascular Research, Berlin, Germany.
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7
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Steinert ND, Jorgenson KW, Lin KH, Hermanson JB, Lemens JL, Hornberger TA. A novel method for visualizing in-vivo rates of protein degradation provides insight into how TRIM28 regulates muscle size. iScience 2023; 26:106526. [PMID: 37070069 PMCID: PMC10105291 DOI: 10.1016/j.isci.2023.106526] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/27/2023] [Accepted: 03/26/2023] [Indexed: 04/03/2023] Open
Abstract
Skeletal muscle size is controlled by the balance between protein synthesis and protein degradation. Given the essential role of skeletal muscle in maintaining a high quality of life, understanding the mechanisms that modulate this balance are of critical importance. Previously, we demonstrated that muscle-specific knockout of TRIM28 reduces muscle size and function and in the current study, we discovered that this effect is associated with an increase in protein degradation and a dramatic reduction in the expression of Mettl21c. Importantly, we also determined that overexpression of Mettl21c is sufficient to induce hypertrophy in both control and TRIM28 knockout muscles. Moreover, we developed a simple pulse-chase biorthogonal non-canonical amino acid tagging technique that enabled us to visualize the in vivo rate of protein degradation, and with this technique were able to conclude that the hypertrophic effect of Mettl21c is due, at least in part, to an inhibition of protein degradation.
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Affiliation(s)
- Nathaniel D. Steinert
- Department of Comparative Biosciences, University of Wisconsin - Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin - Madison, Madison, WI, USA
| | - Kent W. Jorgenson
- Department of Molecular and Cellular Pharmacology, University of Wisconsin - Madison, Madison, WI, USA
- School of Medicine and Public Health, University of Wisconsin - Madison, Madison, WI, USA
| | - Kuan-Hung Lin
- Department of Comparative Biosciences, University of Wisconsin - Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin - Madison, Madison, WI, USA
| | - Jake B. Hermanson
- Department of Comparative Biosciences, University of Wisconsin - Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin - Madison, Madison, WI, USA
| | - Jake L. Lemens
- Department of Comparative Biosciences, University of Wisconsin - Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin - Madison, Madison, WI, USA
| | - Troy A. Hornberger
- Department of Comparative Biosciences, University of Wisconsin - Madison, Madison, WI, USA
- School of Veterinary Medicine, University of Wisconsin - Madison, Madison, WI, USA
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8
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Pacilio S, Costa R, Papa V, Rodia MT, Gotti C, Pagnotta G, Cenacchi G, Focarete ML. Electrospun Poly(L-lactide-co-ε-caprolactone) Scaffold Potentiates C2C12 Myoblast Bioactivity and Acts as a Stimulus for Cell Commitment in Skeletal Muscle Myogenesis. Bioengineering (Basel) 2023; 10:bioengineering10020239. [PMID: 36829733 PMCID: PMC9952728 DOI: 10.3390/bioengineering10020239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
Tissue engineering combines a scaffold, cells and regulatory signals, reproducing a biomimetic extracellular matrix capable of supporting cell attachment and proliferation. We examined the role of an electrospun scaffold made of a biocompatible polymer during the myogenesis of skeletal muscle (SKM) as an alternative approach to tissue regeneration. The engineered nanostructure was obtained by electrospinning poly(L-lactide-co-ε-caprolactone) (PLCL) in the form of a 3D porous nanofibrous scaffold further coated with collagen. C2C12 were cultured on the PLCL scaffold, and cell morphology and differentiation pathways were thoroughly investigated. The functionalized PLCL scaffold recreated the SKM nanostructure and performed its biological functions, guiding myoblast morphogenesis and promoting cell differentiation until tissue formation. The scaffold enabled cell-cell interactions through the development of cellular adhesions that were fundamental during myoblast fusion and myotube formation. Expression of myogenic regulatory markers and muscle-specific proteins at different stages of myogenesis suggested that the PLCL scaffold enhanced myoblast differentiation within a shorter time frame. The functionalized PLCL scaffold impacts myoblast bioactivity and acts as a stimulus for cell commitment, surpassing traditional 2D cell culture techniques. We developed a screening model for tissue development and a device for tissue restoration.
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Affiliation(s)
- Serafina Pacilio
- Department of Biomedical and Neuromotor Sciences DIBINEM, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Applied Biomedical Research Center—CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Department of Chemistry “Giacomo Ciamician”, INSTM UdR of Bologna, University of Bologna, 40100 Bologna, Italy
| | - Roberta Costa
- Department of Biomedical and Neuromotor Sciences DIBINEM, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Applied Biomedical Research Center—CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
| | - Valentina Papa
- Department of Biomedical and Neuromotor Sciences DIBINEM, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
| | - Maria Teresa Rodia
- Department of Biomedical and Neuromotor Sciences DIBINEM, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Applied Biomedical Research Center—CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
| | - Carlo Gotti
- Interdepartmental Center for Industrial Research in Advanced Mechanics and Materials (CIRI-MAM), Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
| | - Giorgia Pagnotta
- Department of Chemistry “Giacomo Ciamician”, INSTM UdR of Bologna, University of Bologna, 40100 Bologna, Italy
| | - Giovanna Cenacchi
- Department of Biomedical and Neuromotor Sciences DIBINEM, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Applied Biomedical Research Center—CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum—University of Bologna, 40100 Bologna, Italy
- Correspondence: ; Tel.: +39-051-2144514
| | - Maria Letizia Focarete
- Department of Chemistry “Giacomo Ciamician”, INSTM UdR of Bologna, University of Bologna, 40100 Bologna, Italy
- Health Sciences & Technologies (HST) CIRI, University of Bologna, Via Tolara di Sopra 41/E, 40064 Ozzano Emilia, Italy
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Ribeiro F, Alves PKN, Bechara LRG, Ferreira JCB, Labeit S, Moriscot AS. Small-Molecule Inhibition of MuRF1 Prevents Early Disuse-Induced Diaphragmatic Dysfunction and Atrophy. Int J Mol Sci 2023; 24:ijms24043637. [PMID: 36835047 PMCID: PMC9965746 DOI: 10.3390/ijms24043637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023] Open
Abstract
In clinical conditions such as diaphragm paralysis or mechanical ventilation, disuse-induced diaphragmatic dysfunction (DIDD) is a condition that poses a threat to life. MuRF1 is a key E3-ligase involved in regulating skeletal muscle mass, function, and metabolism, which contributes to the onset of DIDD. We investigated if the small-molecule mediated inhibition of MuRF1 activity (MyoMed-205) protects against early DIDD after 12 h of unilateral diaphragm denervation. Wistar rats were used in this study to determine the compound's acute toxicity and optimal dosage. For potential DIDD treatment efficacy, diaphragm contractile function and fiber cross-sectional area (CSA) were evaluated. Western blotting investigated potential mechanisms underlying MyoMed-205's effects in early DIDD. Our results indicate 50 mg/kg bw MyoMed-205 as a suitable dosage to prevent early diaphragmatic contractile dysfunction and atrophy following 12 h of denervation without detectable signs of acute toxicity. Mechanistically, treatment did not affect disuse-induced oxidative stress (4-HNE) increase, whereas phosphorylation of (ser632) HDAC4 was normalized. MyoMed-205 also mitigated FoxO1 activation, inhibited MuRF2, and increased phospho (ser473) Akt protein levels. These findings may suggest that MuRF1 activity significantly contributes to early DIDD pathophysiology. Novel strategies targeting MuRF1 (e.g., MyoMed-205) have potential therapeutic applications for treating early DIDD.
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Affiliation(s)
- Fernando Ribeiro
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Paula K. N. Alves
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Luiz R. G. Bechara
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Julio C. B. Ferreira
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
| | - Siegfried Labeit
- DZHK Partner Site Mannheim-Heidelberg, Medical Faculty Mannheim, University of Heidelberg, 68169 Mannheim, Germany
- Myomedix GmbH, 69151 Neckargemünd, Germany
| | - Anselmo S. Moriscot
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, Brazil
- Correspondence: ; Tel.: +55-11-3091-0946
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10
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Yoo SH. Circadian regulation of cardiac muscle function and protein degradation. Chronobiol Int 2023; 40:4-12. [PMID: 34521283 PMCID: PMC8918439 DOI: 10.1080/07420528.2021.1957911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
The circadian clock plays a fundamental role in physiology. In particular, the heart is a target organ where the clock orchestrates various aspects of cardiac function. At the molecular level, the clock machinery governs daily rhythms of gene expression. Such circadian regulation is in tune with the dynamic nature of heart structure and function, and provides the foundation for chronotherapeutic applications in cardiovascular diseases. In comparison, a regulatory role of the clock in cardiac protein degradation is poorly documented. Sarcomere is the structural and functional unit responsible for cardiac muscle contraction, and sarcomere components are closely regulated by protein folding and proteolysis. Emerging evidence supports a role of the circadian clock in governing sarcomere integrity and function. Particularly, recent studies uncovered a circadian regulation of a core sarcomere component TCAP. It is possible that circadian regulation of the cardiac muscle protein turnover is a key regulatory mechanism underlying cardiac remodeling in response to physiological and environmental stimuli. While the detailed regulatory mechanisms and the molecular links to cardiac (patho)physiology remain to be further studied, therapeutic strategies targeting circadian control in the heart may markedly enhance intervention outcomes against cardiovascular disease.
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Affiliation(s)
- Seung-Hee Yoo
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
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11
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HMGB1 Promotes In Vitro and In Vivo Skeletal Muscle Atrophy through an IL-18-Dependent Mechanism. Cells 2022; 11:cells11233936. [PMID: 36497194 PMCID: PMC9740799 DOI: 10.3390/cells11233936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/28/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
Skeletal muscle atrophy occurs due to muscle wasting or reductions in protein associated with aging, injury, and inflammatory processes. High-mobility group box-1 (HMGB1) protein is passively released from necrotic cells and actively secreted by inflammatory cells, and is implicated in the pathogenesis of various inflammatory and immune diseases. HMGB1 is upregulated in muscle inflammation, and circulating levels of the proinflammatory cytokine interleukin-18 (IL-18) are upregulated in patients with sarcopenia, a muscle-wasting disease. We examined whether an association exists between HMGB1 and IL-18 signaling in skeletal muscle atrophy. HMGB1-induced increases of IL-18 levels enhanced the expression of muscle atrophy markers and inhibited myogenic marker expression in C2C12 and G7 myoblast cell lines. HMGB1-induced increases of IL-18 production in C2C12 cells involved the RAGE/p85/Akt/mTOR/c-Jun signaling pathway. HMGB1 short hairpin RNA (shRNA) treatment rescued the expression of muscle-specific differentiation markers in murine C2C12 myotubes and in mice with glycerol-induced muscle atrophy. HMGB1 and IL-18 signaling was suppressed in the mice after HMGB1 shRNA treatment. These findings suggest that the HMGB1/IL-18 axis is worth targeting for the treatment of skeletal muscle atrophy.
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12
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Ubiquitin Ligases in Longevity and Aging Skeletal Muscle. Int J Mol Sci 2022; 23:ijms23147602. [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] [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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13
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Kötter S, Krüger M. Protein Quality Control at the Sarcomere: Titin Protection and Turnover and Implications for Disease Development. Front Physiol 2022; 13:914296. [PMID: 35846001 PMCID: PMC9281568 DOI: 10.3389/fphys.2022.914296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/10/2022] [Indexed: 11/26/2022] Open
Abstract
Sarcomeres are mainly composed of filament and signaling proteins and are the smallest molecular units of muscle contraction and relaxation. The sarcomere protein titin serves as a molecular spring whose stiffness mediates myofilament extensibility in skeletal and cardiac muscle. Due to the enormous size of titin and its tight integration into the sarcomere, the incorporation and degradation of the titin filament is a highly complex task. The details of the molecular processes involved in titin turnover are not fully understood, but the involvement of different intracellular degradation mechanisms has recently been described. This review summarizes the current state of research with particular emphasis on the relationship between titin and protein quality control. We highlight the involvement of the proteasome, autophagy, heat shock proteins, and proteases in the protection and degradation of titin in heart and skeletal muscle. Because the fine-tuned balance of degradation and protein expression can be disrupted under pathological conditions, the review also provides an overview of previously known perturbations in protein quality control and discusses how these affect sarcomeric proteins, and titin in particular, in various disease states.
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14
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Adams V, Schauer A, Augstein A, Kirchhoff V, Draskowski R, Jannasch A, Goto K, Lyall G, Männel A, Barthel P, Mangner N, Winzer EB, Linke A, Labeit S. Targeting MuRF1 by small molecules in a HFpEF rat model improves myocardial diastolic function and skeletal muscle contractility. J Cachexia Sarcopenia Muscle 2022; 13:1565-1581. [PMID: 35301823 PMCID: PMC9178400 DOI: 10.1002/jcsm.12968] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/16/2022] [Accepted: 02/18/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND About half of heart failure (HF) patients, while having preserved left ventricular function, suffer from diastolic dysfunction (so-called HFpEF). No specific therapeutics are available for HFpEF in contrast to HF where reduced ejection fractions (HFrEF) can be treated pharmacologically. Myocardial titin filament stiffening, endothelial dysfunction, and skeletal muscle (SKM) myopathy are suspected to contribute to HFpEF genesis. We previously described small molecules interfering with MuRF1 target recognition thereby attenuating SKM myopathy and dysfunction in HFrEF animal models. The aim of the present study was to test the efficacy of one small molecule (MyoMed-205) in HFpEF and to describe molecular changes elicited by MyoMed-205. METHODS Twenty-week-old female obese ZSF1 rats received the MuRF1 inhibitor MyoMed-205 for 12 weeks; a comparison was made to age-matched untreated ZSF1-lean (healthy) and obese rats as controls. LV (left ventricle) function was assessed by echocardiography and by invasive haemodynamic measurements until week 32. At week 32, SKM and endothelial functions were measured and tissues collected for molecular analyses. Proteome-wide analysis followed by WBs and RT-PCR was applied to identify specific genes and affected molecular pathways. MuRF1 knockout mice (MuRF1-KO) SKM tissues were included to validate MuRF1-specificity. RESULTS By week 32, untreated obese rats had normal LV ejection fraction but augmented E/e' ratios and increased end diastolic pressure and myocardial fibrosis, all typical features of HFpEF. Furthermore, SKM myopathy (both atrophy and force loss) and endothelial dysfunction were detected. In contrast, MyoMed-205 treated rats had markedly improved diastolic function, less myocardial fibrosis, reduced SKM myopathy, and increased SKM function. SKM extracts from MyoMed-205 treated rats had reduced MuRF1 content and lowered total muscle protein ubiquitination. In addition, proteomic profiling identified eight proteins to respond specifically to MyoMed-205 treatment. Five out of these eight proteins are involved in mitochondrial metabolism, dynamics, or autophagy. Consistent with the mitochondria being a MyoMed-205 target, the synthesis of mitochondrial respiratory chain complexes I + II was increased in treated rats. MuRF1-KO SKM controls also had elevated mitochondrial complex I and II activities, also suggesting mitochondrial activity regulation by MuRF1. CONCLUSIONS MyoMed-205 improved myocardial diastolic function and prevented SKM atrophy/function in the ZSF1 animal model of HFpEF. Mechanistically, SKM benefited from an attenuated ubiquitin proteasome system and augmented synthesis/activity of proteins of the mitochondrial respiratory chain while the myocardium seemed to benefit from reduced titin modifications and fibrosis.
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Affiliation(s)
- Volker Adams
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
- Dresden Cardiovascular Research Institute and Core Laboratories GmbHDresdenGermany
| | - Antje Schauer
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Antje Augstein
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Virginia Kirchhoff
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Runa Draskowski
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Anett Jannasch
- Department of Cardiac SurgeryTU Dresden, Heart Center DresdenDresdenGermany
| | - Keita Goto
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Gemma Lyall
- School of Biomedical SciencesUniversity of LeedsLeedsUK
| | - Anita Männel
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Peggy Barthel
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Norman Mangner
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Ephraim B. Winzer
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
| | - Axel Linke
- Laboratory of Molecular and Experimental CardiologyTU Dresden, Heart Center DresdenDresdenGermany
- Dresden Cardiovascular Research Institute and Core Laboratories GmbHDresdenGermany
| | - Siegfried Labeit
- Myomedix GmbHNeckargemündGermany
- DZHK (German Center for Cardiovascular Research), partner site Heidelberg/MannheimMannheimGermany
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15
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Kny M, Fielitz J. Hidden Agenda - The Involvement of Endoplasmic Reticulum Stress and Unfolded Protein Response in Inflammation-Induced Muscle Wasting. Front Immunol 2022; 13:878755. [PMID: 35615361 PMCID: PMC9124858 DOI: 10.3389/fimmu.2022.878755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Critically ill patients at the intensive care unit (ICU) often develop a generalized weakness, called ICU-acquired weakness (ICUAW). A major contributor to ICUAW is muscle atrophy, a loss of skeletal muscle mass and function. Skeletal muscle assures almost all of the vital functions of our body. It adapts rapidly in response to physiological as well as pathological stress, such as inactivity, immobilization, and inflammation. In response to a reduced workload or inflammation muscle atrophy develops. Recent work suggests that adaptive or maladaptive processes in the endoplasmic reticulum (ER), also known as sarcoplasmic reticulum, contributes to this process. In muscle cells, the ER is a highly specialized cellular organelle that assures calcium homeostasis and therefore muscle contraction. The ER also assures correct folding of proteins that are secreted or localized to the cell membrane. Protein folding is a highly error prone process and accumulation of misfolded or unfolded proteins can cause ER stress, which is counteracted by the activation of a signaling network known as the unfolded protein response (UPR). Three ER membrane residing molecules, protein kinase R-like endoplasmic reticulum kinase (PERK), inositol requiring protein 1a (IRE1a), and activating transcription factor 6 (ATF6) initiate the UPR. The UPR aims to restore ER homeostasis by reducing overall protein synthesis and increasing gene expression of various ER chaperone proteins. If ER stress persists or cannot be resolved cell death pathways are activated. Although, ER stress-induced UPR pathways are known to be important for regulation of skeletal muscle mass and function as well as for inflammation and immune response its function in ICUAW is still elusive. Given recent advances in the development of ER stress modifying molecules for neurodegenerative diseases and cancer, it is important to know whether or not therapeutic interventions in ER stress pathways have favorable effects and these compounds can be used to prevent or treat ICUAW. In this review, we focus on the role of ER stress-induced UPR in skeletal muscle during critical illness and in response to predisposing risk factors such as immobilization, starvation and inflammation as well as ICUAW treatment to foster research for this devastating clinical problem.
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Affiliation(s)
- Melanie Kny
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Jens Fielitz
- Department of Molecular Cardiology, DZHK (German Center for Cardiovascular Research), Partner Site, Greifswald, Germany
- Department of Internal Medicine B, Cardiology, University Medicine Greifswald, Greifswald, Germany
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16
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Clemente-Suárez VJ, Redondo-Flórez L, Rubio-Zarapuz A, Martínez-Guardado I, Navarro-Jiménez E, Tornero-Aguilera JF. Nutritional and Exercise Interventions in Cancer-Related Cachexia: An Extensive Narrative Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:4604. [PMID: 35457471 PMCID: PMC9025820 DOI: 10.3390/ijerph19084604] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/04/2022] [Accepted: 04/08/2022] [Indexed: 01/27/2023]
Abstract
One of the common traits found in cancer patients is malnutrition and cachexia, which affects between 25% to 60% of the patients, depending on the type of cancer, diagnosis, and treatment. Given the lack of current effective pharmacological solutions for low muscle mass and sarcopenia, holistic interventions are essential to patient care, as well as exercise and nutrition. Thus, the present narrative review aimed to analyze the nutritional, pharmacological, ergonutritional, and physical exercise strategies in cancer-related cachexia. The integration of multidisciplinary interventions could help to improve the final intervention in patients, improving their prognosis, quality of life, and life expectancy. To reach these aims, an extensive narrative review was conducted. The databases used were MedLine (PubMed), Cochrane (Wiley), Embase, PsychINFO, and CinAhl. Cancer-related cachexia is a complex multifactorial phenomenon in which systemic inflammation plays a key role in the development and maintenance of the symptomatology. Pharmacological interventions seem to produce a positive effect on inflammatory state and cachexia. Nutritional interventions are focused on a high-energy diet with high-density foods and the supplementation with antioxidants, while physical activity is focused on strength-based training. The implementation of multidisciplinary non-pharmacological interventions in cancer-related cachexia could be an important tool to improve traditional treatments and improve patients' quality of life.
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Affiliation(s)
- Vicente Javier Clemente-Suárez
- Faculty of Sports Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (L.R.-F.); (A.R.-Z.); (J.F.T.-A.)
- Grupo de Investigación en Cultura, Educación y Sociedad, Universidad de la Costa, Barranquilla 080002, Colombia
| | - Laura Redondo-Flórez
- Faculty of Sports Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (L.R.-F.); (A.R.-Z.); (J.F.T.-A.)
| | - Alejandro Rubio-Zarapuz
- Faculty of Sports Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain; (L.R.-F.); (A.R.-Z.); (J.F.T.-A.)
| | - Ismael Martínez-Guardado
- BRABE Group, Department of Psychology, Faculty of Life and Natural Sciences, University of Nebrija, C/del Hostal, 28248 Madrid, Spain;
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17
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Andreeva S, Chumakova O, Karelkina E, Lebedeva V, Lubimtseva T, Semenov A, Nikitin A, Speshilov G, Kozyreva A, Sokolnikova P, Zhuk S, Fomicheva Y, Moiseeva O, Kostareva A. Case Report: Two New Cases of Autosomal-Recessive Hypertrophic Cardiomyopathy Associated With TRIM63-Compound Heterozygous Variant. Front Genet 2022; 13:743472. [PMID: 35273634 PMCID: PMC8901572 DOI: 10.3389/fgene.2022.743472] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Accepted: 01/14/2022] [Indexed: 12/15/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is one of the most common hereditary diseases, and it is associated with fatal complications. The clinical heterogeneity of HCM requires risk prediction models to identify patients at a high risk of adverse events. Most HCM cases are caused by mutations in genes encoding sarcomere proteins. However, HCM is associated with rare genetic variants with limited data about its clinical course and prognosis, and existing risk prediction models are not validated for such patients' cohorts. TRIM63 is one of the rare genes recently described as a cause of HCM with autosomal-recessive inheritance. Herein, we present two cases of HCM associated with TRIM63-compound heterozygous variants in young male sportsmen. They demonstrated progressively marked hypertrophy, advanced diastolic dysfunction, a significant degree of fibrosis detected by magnetic resonance imaging, and clear indications for implantable cardioverter-defibrillator. One of the cases includes the first description of TRIM63-HCM with extreme hypertrophy. The presented cases are discussed in light of molecular consequences that might underlie cardiac and muscle phenotype in patients with mutations of TRIM63, the master regulator of striated muscle mass.
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Affiliation(s)
- Sofiya Andreeva
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Olga Chumakova
- Central State Medical Academy of Department of Presidential Affairs, City Clinical Hospital #17, Moscow, Russia
| | - Elena Karelkina
- Institute of Heart and Vessels, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Viktoriya Lebedeva
- Institute of Heart and Vessels, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Tamara Lubimtseva
- Institute of Heart and Vessels, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Andrey Semenov
- Institute of Heart and Vessels, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Alexey Nikitin
- Pulmonology Research Institute, Federal Medical-Biological Agency of Russia, Moscow, Russia
| | - Gleb Speshilov
- Laboratory of Genotyping, N. F. Gamaleya National Research Center, Moscow, Russia
| | - Alexandra Kozyreva
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Polina Sokolnikova
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Sergey Zhuk
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Yuliya Fomicheva
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Olga Moiseeva
- Institute of Heart and Vessels, Almazov National Medical Research Centre, Saint Petersburg, Russia
| | - Anna Kostareva
- Institute of Molecular Biology and Genetics and World-Class Research Centre for Personalized Medicine, Almazov National Medical Research Centre, Saint Petersburg, Russia.,Department of Women's and Children's Health and Center for Molecular Medicine, Karolinska Institute, Solna, Sweden
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18
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Aase-Remedios ME, Coll-Lladó C, Ferrier DEK. Amphioxus muscle transcriptomes reveal vertebrate-like myoblast fusion genes and a highly conserved role of insulin signalling in the metabolism of muscle. BMC Genomics 2022; 23:93. [PMID: 35105312 PMCID: PMC8805411 DOI: 10.1186/s12864-021-08222-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The formation and functioning of muscles are fundamental aspects of animal biology, and the evolution of 'muscle genes' is central to our understanding of this tissue. Feeding-fasting-refeeding experiments have been widely used to assess muscle cellular and metabolic responses to nutrition. Though these studies have focused on vertebrate models and only a few invertebrate systems, they have found similar processes are involved in muscle degradation and maintenance. Motivation for these studies stems from interest in diseases whose pathologies involve muscle atrophy, a symptom also triggered by fasting, as well as commercial interest in the muscle mass of animals kept for consumption. Experimentally modelling atrophy by manipulating nutritional state causes muscle mass to be depleted during starvation and replenished with refeeding so that the genetic mechanisms controlling muscle growth and degradation can be understood. RESULTS Using amphioxus, the earliest branching chordate lineage, we address the gap in previous work stemming from comparisons between distantly related vertebrate and invertebrate models. Our amphioxus feeding-fasting-refeeding muscle transcriptomes reveal a highly conserved myogenic program and that the pro-orthologues of many vertebrate myoblast fusion genes were present in the ancestral chordate, despite these invertebrate chordates having unfused mononucleate myocytes. We found that genes differentially expressed between fed and fasted amphioxus were orthologous to the genes that respond to nutritional state in vertebrates. This response is driven in a large part by the highly conserved IGF/Akt/FOXO pathway, where depleted nutrient levels result in activation of FOXO, a transcription factor with many autophagy-related gene targets. CONCLUSION Reconstruction of these gene networks and pathways in amphioxus muscle provides a key point of comparison between the distantly related groups assessed thus far, significantly refining the reconstruction of the ancestral state for chordate myoblast fusion genes and identifying the extensive role of duplicated genes in the IGF/Akt/FOXO pathway across animals. Our study elucidates the evolutionary trajectory of muscle genes as they relate to the increased complexity of vertebrate muscles and muscle development.
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Affiliation(s)
- Madeleine E Aase-Remedios
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
| | - Clara Coll-Lladó
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
| | - David E K Ferrier
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK.
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19
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Sawano S, Kobayashi Y, Maesawa S, Mizunoya W. Egg components reverse the atrophy induced by injury in skeletal muscles. Genes Cells 2021; 27:138-144. [PMID: 34929062 DOI: 10.1111/gtc.12915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 11/26/2021] [Accepted: 12/10/2021] [Indexed: 11/29/2022]
Abstract
Skeletal muscle atrophy is the loss of muscle tissue caused by factors such as inactivity, malnutrition, aging, and injury. In this study, we aimed to investigate whether egg components exert inhibitory effects on muscle atrophy. An egg mix solution was orally administered for 10 consecutive days to male C57BL/6J mice injected with cardiotoxin in the tibialis anterior (TA) muscle. The administration of egg mixture significantly decreased the atrogin-1 and MuRF-1 protein levels, key factors in muscle atrophy, as observed by western blotting. Furthermore, we investigated the effects of egg components such as avidin, lecithin, biotin, 3-sn-phosphatidylcholine, and L-α-phosphatidylcholine on dexamethasone (DEX)-treated C2C12 myotubes. Lecithin, biotin, 3-sn-phosphatidylcholine, and L-α-phosphatidylcholine in egg yolk significantly recovered the diameters of C2C12 myotubes decreased upon DEX application. Avidin did not show such reversal. Biotin, 3-sn-phosphatidylcholine, and L-α-phosphatidylcholine also attenuated atrogin-1 protein expression enhanced by DEX. Our findings reveal that egg yolk components could contribute to the reversal of skeletal muscle atrophy induced by muscle injury.
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Affiliation(s)
- Shoko Sawano
- Department of Food and Life Science, School of Life and Environmental Science, Azabu University, Sagamihara, 252-5201, Japan
| | - Yuya Kobayashi
- Department of Food and Life Science, School of Life and Environmental Science, Azabu University, Sagamihara, 252-5201, Japan
| | - Suzuka Maesawa
- Department of Food and Life Science, School of Life and Environmental Science, Azabu University, Sagamihara, 252-5201, Japan
| | - Wataru Mizunoya
- Department of Animal Science and Biotechnology, School of Veterinary Medicine, Azabu University, Sagamihara, 252-5201, Japan
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20
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Solís C, Russell B. Striated muscle proteins are regulated both by mechanical deformation and by chemical post-translational modification. Biophys Rev 2021; 13:679-695. [PMID: 34777614 DOI: 10.1007/s12551-021-00835-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/23/2021] [Indexed: 01/09/2023] Open
Abstract
All cells sense force and build their cytoskeleton to optimize function. How is this achieved? Two major systems are involved. The first is that load deforms specific protein structures in a proportional and orientation-dependent manner. The second is post-translational modification of proteins as a consequence of signaling pathway activation. These two processes work together in a complex way so that local subcellular assembly as well as overall cell function are controlled. This review discusses many cell types but focuses on striated muscle. Detailed information is provided on how load deforms the structure of proteins in the focal adhesions and filaments, using α-actinin, vinculin, talin, focal adhesion kinase, LIM domain-containing proteins, filamin, myosin, titin, and telethonin as examples. Second messenger signals arising from external triggers are distributed throughout the cell causing post-translational or chemical modifications of protein structures, with the actin capping protein CapZ and troponin as examples. There are numerous unanswered questions of how mechanical and chemical signals are integrated by muscle proteins to regulate sarcomere structure and function yet to be studied. Therefore, more research is needed to see how external triggers are integrated with local tension generated within the cell. Nonetheless, maintenance of tension in the sarcomere is the essential and dominant mechanism, leading to the well-known phrase in exercise physiology: "use it or lose it."
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Affiliation(s)
- Christopher Solís
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612 USA
| | - Brenda Russell
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612 USA
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21
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Fomin A, Gärtner A, Cyganek L, Tiburcy M, Tuleta I, Wellers L, Folsche L, Hobbach AJ, von Frieling-Salewsky M, Unger A, Hucke A, Koser F, Kassner A, Sielemann K, Streckfuß-Bömeke K, Hasenfuss G, Goedel A, Laugwitz KL, Moretti A, Gummert JF, Dos Remedios CG, Reinecke H, Knöll R, van Heesch S, Hubner N, Zimmermann WH, Milting H, Linke WA. Truncated titin proteins and titin haploinsufficiency are targets for functional recovery in human cardiomyopathy due to TTN mutations. Sci Transl Med 2021; 13:eabd3079. [PMID: 34731013 DOI: 10.1126/scitranslmed.abd3079] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Andrey Fomin
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany
| | - Anna Gärtner
- Erich and Hanna Klessmann Institute, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany
| | - Lukas Cyganek
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany.,Stem Cell Unit, University Medical Center, 37075 Göttingen, Germany.,Institute of Pharmacology and Toxicology, University Medical Center, 37075 Göttingen, Germany
| | - Malte Tiburcy
- German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany.,Institute of Pharmacology and Toxicology, University Medical Center, 37075 Göttingen, Germany
| | - Izabela Tuleta
- Department of Cardiology I, Coronary, Peripheral Vascular Disease and Heart Failure, 48149 University Hospital Münster, Münster, Germany
| | - Luisa Wellers
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Lina Folsche
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Anastasia J Hobbach
- Department of Cardiology I, Coronary, Peripheral Vascular Disease and Heart Failure, 48149 University Hospital Münster, Münster, Germany
| | | | - Andreas Unger
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Anna Hucke
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Franziska Koser
- Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Astrid Kassner
- Erich and Hanna Klessmann Institute, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany
| | - Katharina Sielemann
- Erich and Hanna Klessmann Institute, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany
| | - Katrin Streckfuß-Bömeke
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany
| | - Gerd Hasenfuss
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany
| | - Alexander Goedel
- First Medical Department, Cardiology, Technical University of Munich, 81675 Munich, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Munich, Germany.,Department of Cell and Molecular Biology, Karolinska Institute, S-17177 Stockholm, Sweden
| | - Karl-Ludwig Laugwitz
- First Medical Department, Cardiology, Technical University of Munich, 81675 Munich, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Munich, Germany.,Munich Heart Alliance, 80802 Munich, Germany
| | - Alessandra Moretti
- First Medical Department, Cardiology, Technical University of Munich, 81675 Munich, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Munich, Germany.,Munich Heart Alliance, 80802 Munich, Germany
| | - Jan F Gummert
- Erich and Hanna Klessmann Institute, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany.,Department of Cardio-Thoracic Surgery, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany
| | | | - Holger Reinecke
- Department of Cardiology I, Coronary, Peripheral Vascular Disease and Heart Failure, 48149 University Hospital Münster, Münster, Germany
| | - Ralph Knöll
- Department of Medicine, Integrated Cardio Metabolic Centre (ICMC), Heart and Vascular Theme, Karolinska Institute, S-17177 Stockholm, Sweden.,Bioscience Cardiovascular, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, 43183 Gothenburg, Sweden
| | - Sebastiaan van Heesch
- Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Berlin, Germany.,Princess Máxima Center for Pediatric Oncology, 3584 CT Utrecht, Netherlands
| | - Norbert Hubner
- Cardiovascular and Metabolic Sciences, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Berlin, Germany.,Charité-Universitätsmedizin, 10117 Berlin, Germany.,Berlin Institute of Health, 10178 Berlin, Germany
| | - Wolfram H Zimmermann
- German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany.,Institute of Pharmacology and Toxicology, University Medical Center, 37075 Göttingen, Germany.,Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells," University of Göttingen, 37073 Göttingen, Germany
| | - Hendrik Milting
- Erich and Hanna Klessmann Institute, Heart and Diabetes Centre NRW, University Hospital of the Ruhr-University Bochum, 32545 Bad Oeynhausen, Germany
| | - Wolfgang A Linke
- Clinic for Cardiology and Pneumology, University Medical Center, 37075 Göttingen, Germany.,German Centre for Cardiovascular Research, 10785 Berlin, partner site Göttingen, Germany.,Institute of Physiology II, University of Münster, 48149 Münster, Germany
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22
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Müller E, Salcan S, Bongardt S, Barbosa DM, Krüger M, Kötter S. E3-ligase knock down revealed differential titin degradation by autopagy and the ubiquitin proteasome system. Sci Rep 2021; 11:21134. [PMID: 34702928 PMCID: PMC8548520 DOI: 10.1038/s41598-021-00618-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 09/30/2021] [Indexed: 01/09/2023] Open
Abstract
The sarcomere protein titin is a major determinant of cardiomyocyte stiffness and ventricular distensibility. The constant mechanical stress on titin requires well-controlled protein quality control, the exact mechanisms of which have not yet been fully elucidated. Here, we analyzed E3-ligases potentially responsible for cardiac titin ubiquitination and specifically studied the involvement of the autophagosomal system in titin degradation. Pharmacological inhibition of autophagy and the proteasome in cultured primary rat cardiomyocytes significantly elevated titin ubiquitination and increased titin degradation. Using in-vitro pull down assays we identified binding of E3-ligases MuRF1-3, CHIP and Fbx32 to several titin domains. Immunofluorescence analysis showed sarcomeric localization of the E3-ligases. siRNA-mediated knock-down of the E3-ligases MuRF-1, -3 and a combination of CHIP/Fbx32 significantly reduced autophagy-related titin ubiquitination, whereas knock-down of MuRF-2 and -3 reduced proteasome-related titin ubiquitination. We demonstrated that the proteasomal and the autophagosomal-lysosomal system participate in degradation of the titin filament. We found that ubiquitination and degradation of titin are partially regulated by E3-ligases of the MuRF family. We further identified CHIP and Fbx32 as E3-ligases involved in titin ubiquitination.
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Affiliation(s)
- Erik Müller
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany
| | - Senem Salcan
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany
| | - Sabine Bongardt
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany
| | - David Monteiro Barbosa
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany
| | - Martina Krüger
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany
| | - Sebastian Kötter
- Department of Cardiovascular Physiology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 22.03 02, 40225, Düsseldorf, Germany.
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23
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Loescher CM, Hobbach AJ, Linke WA. Titin (TTN): from molecule to modifications, mechanics and medical significance. Cardiovasc Res 2021; 118:2903-2918. [PMID: 34662387 PMCID: PMC9648829 DOI: 10.1093/cvr/cvab328] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/13/2021] [Indexed: 12/19/2022] Open
Abstract
The giant sarcomere protein titin is a major determinant of cardiomyocyte stiffness and contributor to cardiac strain sensing. Titin-based forces are highly regulated in health and disease, which aids in the regulation of myocardial function, including cardiac filling and output. Due to the enormous size, complexity, and malleability of the titin molecule, titin properties are also vulnerable to dysregulation, as observed in various cardiac disorders. This review provides an overview of how cardiac titin properties can be changed at a molecular level, including the role isoform diversity and post-translational modifications (acetylation, oxidation, and phosphorylation) play in regulating myocardial stiffness and contractility. We then consider how this regulation becomes unbalanced in heart disease, with an emphasis on changes in titin stiffness and protein quality control. In this context, new insights into the key pathomechanisms of human cardiomyopathy due to a truncation in the titin gene (TTN) are discussed. Along the way, we touch on the potential for titin to be therapeutically targeted to treat acquired or inherited cardiac conditions, such as HFpEF or TTN-truncation cardiomyopathy.
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Affiliation(s)
- Christine M Loescher
- Institute of Physiology II, University Hospital Münster, Robert-Koch-Str. 27B, Münster, 48149 Germany
| | - Anastasia J Hobbach
- Department of Cardiology I, Coronary, Peripheral Vascular Disease and Heart Failure, University Hospital Münster, Münster, Germany
| | - Wolfgang A Linke
- Institute of Physiology II, University Hospital Münster, Robert-Koch-Str. 27B, Münster, 48149 Germany
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24
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Neurohr JM, Paulson ET, Kinsey ST. A higher mitochondrial content is associated with greater oxidative damage, oxidative defenses, protein synthesis and ATP turnover in resting skeletal muscle. J Exp Biol 2021; 224:jeb242462. [PMID: 34581401 PMCID: PMC8541733 DOI: 10.1242/jeb.242462] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 09/15/2021] [Indexed: 01/13/2023]
Abstract
An unavoidable consequence of aerobic metabolism is the production of reactive oxygen species (ROS). Mitochondria have historically been considered the primary source of ROS; however, recent literature has highlighted the uncertainty in primary ROS production sites and it is unclear how variation in mitochondrial density influences ROS-induced damage and protein turnover. Fish skeletal muscle is composed of distinct, highly aerobic red muscle and anaerobic white muscle, offering an excellent model system in which to evaluate the relationship of tissue aerobic capacity and ROS-induced damage under baseline conditions. The present study used a suite of indices to better understand potential consequences of aerobic tissue capacity in red and white muscle of the pinfish, Lagodon rhomboides. Red muscle had a 7-fold greater mitochondrial volume density than white muscle, and more oxidative damage despite also having higher activity of the antioxidant enzymes superoxide dismutase and catalase. The dominant protein degradation system appears to be tissue dependent. Lysosomal degradation markers and autophagosome volume density were greater in white muscle, while ubiquitin expression and 20S proteasome activity were significantly greater in red muscle. However, ubiquitin ligase expression was significantly higher in white muscle. Red muscle had a more than 2-fold greater rate of translation and total ATP turnover than white muscle, results that may be due in part to the higher mitochondrial density and the associated increase in oxidative damage. Together, these results support the concept that an elevated aerobic capacity is associated with greater oxidative damage and higher costs of protein turnover.
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Affiliation(s)
| | | | - Stephen T. Kinsey
- University of North Carolina Wilmington, Department of Biology and Marine Biology, 601 S. College Road, Wilmington, NC 28403, USA
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25
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Haberecht-Müller S, Krüger E, Fielitz J. Out of Control: The Role of the Ubiquitin Proteasome System in Skeletal Muscle during Inflammation. Biomolecules 2021; 11:biom11091327. [PMID: 34572540 PMCID: PMC8468834 DOI: 10.3390/biom11091327] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 02/07/2023] Open
Abstract
The majority of critically ill intensive care unit (ICU) patients with severe sepsis develop ICU-acquired weakness (ICUAW) characterized by loss of muscle mass, reduction in myofiber size and decreased muscle strength leading to persisting physical impairment. This phenotype results from a dysregulated protein homeostasis with increased protein degradation and decreased protein synthesis, eventually causing a decrease in muscle structural proteins. The ubiquitin proteasome system (UPS) is the predominant protein-degrading system in muscle that is activated during diverse muscle atrophy conditions, e.g., inflammation. The specificity of UPS-mediated protein degradation is assured by E3 ubiquitin ligases, such as atrogin-1 and MuRF1, which target structural and contractile proteins, proteins involved in energy metabolism and transcription factors for UPS-dependent degradation. Although the regulation of activity and function of E3 ubiquitin ligases in inflammation-induced muscle atrophy is well perceived, the contribution of the proteasome to muscle atrophy during inflammation is still elusive. During inflammation, a shift from standard- to immunoproteasome was described; however, to which extent this contributes to muscle wasting and whether this changes targeting of specific muscular proteins is not well described. This review summarizes the function of the main proinflammatory cytokines and acute phase response proteins and their signaling pathways in inflammation-induced muscle atrophy with a focus on UPS-mediated protein degradation in muscle during sepsis. The regulation and target-specificity of the main E3 ubiquitin ligases in muscle atrophy and their mode of action on myofibrillar proteins will be reported. The function of the standard- and immunoproteasome in inflammation-induced muscle atrophy will be described and the effects of proteasome-inhibitors as treatment strategies will be discussed.
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Affiliation(s)
- Stefanie Haberecht-Müller
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, 17475 Greifswald, Germany;
| | - Elke Krüger
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, 17475 Greifswald, Germany;
- Correspondence: (E.K.); (J.F.)
| | - Jens Fielitz
- DZHK (German Centre for Cardiovascular Research), Partner Site Greifswald, 17475 Greifswald, Germany
- Department of Internal Medicine B, Cardiology, University Medicine Greifswald, 17475 Greifswald, Germany
- Correspondence: (E.K.); (J.F.)
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26
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Jirka C, Pak JH, Grosgogeat CA, Marchetii MM, Gupta VA. Dysregulation of NRAP degradation by KLHL41 contributes to pathophysiology in nemaline myopathy. Hum Mol Genet 2021; 28:2549-2560. [PMID: 30986853 DOI: 10.1093/hmg/ddz078] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/29/2019] [Accepted: 04/08/2019] [Indexed: 12/13/2022] Open
Abstract
Nemaline myopathy (NM) is the most common form of congenital myopathy that results in hypotonia and muscle weakness. This disease is clinically and genetically heterogeneous, but three recently discovered genes in NM encode for members of the Kelch family of proteins. Kelch proteins act as substrate-specific adaptors for Cullin 3 (CUL3) E3 ubiquitin ligase to regulate protein turnover through the ubiquitin-proteasome machinery. Defects in thin filament formation and/or stability are key molecular processes that underlie the disease pathology in NM; however, the role of Kelch proteins in these processes in normal and diseases conditions remains elusive. Here, we describe a role of NM causing Kelch protein, KLHL41, in premyofibil-myofibil transition during skeletal muscle development through a regulation of the thin filament chaperone, nebulin-related anchoring protein (NRAP). KLHL41 binds to the thin filament chaperone NRAP and promotes ubiquitination and subsequent degradation of NRAP, a process that is critical for the formation of mature myofibrils. KLHL41 deficiency results in abnormal accumulation of NRAP in muscle cells. NRAP overexpression in transgenic zebrafish resulted in a severe myopathic phenotype and absence of mature myofibrils demonstrating a role in disease pathology. Reducing Nrap levels in KLHL41 deficient zebrafish rescues the structural and function defects associated with disease pathology. We conclude that defects in KLHL41-mediated ubiquitination of sarcomeric proteins contribute to structural and functional deficits in skeletal muscle. These findings further our understanding of how the sarcomere assembly is regulated by disease-causing factors in vivo, which will be imperative for developing mechanism-based specific therapeutic interventions.
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Affiliation(s)
- Caroline Jirka
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jasmine H Pak
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Claire A Grosgogeat
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Vandana A Gupta
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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27
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Baehr LM, Hughes DC, Lynch SA, Van Haver D, Maia TM, Marshall AG, Radoshevich L, Impens F, Waddell DS, Bodine SC. Identification of the MuRF1 Skeletal Muscle Ubiquitylome Through Quantitative Proteomics. FUNCTION (OXFORD, ENGLAND) 2021; 2:zqab029. [PMID: 34179788 PMCID: PMC8218097 DOI: 10.1093/function/zqab029] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/12/2021] [Accepted: 05/17/2021] [Indexed: 02/07/2023]
Abstract
MuRF1 (TRIM63) is a muscle-specific E3 ubiquitin ligase and component of the ubiquitin proteasome system. MuRF1 is transcriptionally upregulated under conditions that cause muscle loss, in both rodents and humans, and is a recognized marker of muscle atrophy. In this study, we used in vivo electroporation to determine whether MuRF1 overexpression alone can cause muscle atrophy and, in combination with ubiquitin proteomics, identify the endogenous MuRF1 substrates in skeletal muscle. Overexpression of MuRF1 in adult mice increases ubiquitination of myofibrillar and sarcoplasmic proteins, increases expression of genes associated with neuromuscular junction instability, and causes muscle atrophy. A total of 169 ubiquitination sites on 56 proteins were found to be regulated by MuRF1. MuRF1-mediated ubiquitination targeted both thick and thin filament contractile proteins, as well as, glycolytic enzymes, deubiquitinases, p62, and VCP. These data reveal a potential role for MuRF1 in not only the breakdown of the sarcomere but also the regulation of metabolism and other proteolytic pathways in skeletal muscle.
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Affiliation(s)
| | | | - Sarah A Lynch
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
| | - Delphi Van Haver
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - Teresa Mendes Maia
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - Andrea G Marshall
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Lilliana Radoshevich
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Francis Impens
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium,VIB Center for Medical Biotechnology, Ghent, Belgium,VIB Proteomics Core, Ghent, Belgium
| | - David S Waddell
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
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28
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Wirianto M, Yang J, Kim E, Gao S, Paudel KR, Choi JM, Choe J, Gloston GF, Ademoji P, Parakramaweera R, Jin J, Esser KA, Jung SY, Geng YJ, Lee HK, Chen Z, Yoo SH. The GSK-3β-FBXL21 Axis Contributes to Circadian TCAP Degradation and Skeletal Muscle Function. Cell Rep 2021; 32:108140. [PMID: 32937135 PMCID: PMC8299398 DOI: 10.1016/j.celrep.2020.108140] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/04/2020] [Accepted: 08/21/2020] [Indexed: 12/19/2022] Open
Abstract
FBXL21 is a clock-controlled E3 ligase modulating circadian periodicity via subcellular-specific CRYPTOCHROME degradation. How FBXL21 regulates tissue-specific circadian physiology and what mechanism operates upstream is poorly understood. Here we report the sarcomere component TCAP as a cytoplasmic substrate of FBXL21. FBXL21 interacts with TCAP in a circadian manner antiphasic to TCAP accumulation in skeletal muscle, and circadian TCAP oscillation is disrupted in Psttm mice with an Fbxl21 hypomorph mutation. GSK-3β phosphorylates FBXL21 and TCAP to activate FBXL21-mediated, phosphodegron-dependent TCAP degradation. GSK-3β inhibition or knockdown diminishes FBXL21-Cul1 complex formation and delays FBXL21-mediated TCAP degradation. Finally, Psttm mice show significant skeletal muscle defects, including impaired fiber size, exercise tolerance, grip strength, and response to glucocorticoid-induced atrophy, in conjunction with cardiac dysfunction. These data highlight a circadian regulatory pathway where a GSK-3β-FBXL21 functional axis controls TCAP degradation via SCF complex formation and regulates skeletal muscle function. Wirianto et al. find that the circadian E3 ligase FBXL21 drives rhythmic degradation of the sarcomeric protein TCAP in skeletal muscle. GSK-3β co-phosphorylates FBXL21 and TCAP and promotes SCF complex formation and phosphodegron-dependent TCAP turnover. Psttm mice, expressing a hypomorphic Fbxl21 mutant, show dysregulated TCAP degradation and impaired muscle function.
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Affiliation(s)
- Marvin Wirianto
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Jiah Yang
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Eunju Kim
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Song Gao
- Department of Internal Medicine, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Keshav Raj Paudel
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Jong Min Choi
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Jeehwan Choe
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Gabrielle F Gloston
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Precious Ademoji
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Randika Parakramaweera
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Jianping Jin
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Karyn A Esser
- Department of Physiology and Functional Genomics, The University of Florida College of Medicine, Gainesville, FL 32610-0274, USA
| | - Sung Yun Jung
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Yong-Jian Geng
- Department of Internal Medicine, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Hyun Kyoung Lee
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Zheng Chen
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
| | - Seung-Hee Yoo
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA.
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29
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The Role of Z-disc Proteins in Myopathy and Cardiomyopathy. Int J Mol Sci 2021; 22:ijms22063058. [PMID: 33802723 PMCID: PMC8002584 DOI: 10.3390/ijms22063058] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/07/2021] [Accepted: 03/11/2021] [Indexed: 12/11/2022] Open
Abstract
The Z-disc acts as a protein-rich structure to tether thin filament in the contractile units, the sarcomeres, of striated muscle cells. Proteins found in the Z-disc are integral for maintaining the architecture of the sarcomere. They also enable it to function as a (bio-mechanical) signalling hub. Numerous proteins interact in the Z-disc to facilitate force transduction and intracellular signalling in both cardiac and skeletal muscle. This review will focus on six key Z-disc proteins: α-actinin 2, filamin C, myopalladin, myotilin, telethonin and Z-disc alternatively spliced PDZ-motif (ZASP), which have all been linked to myopathies and cardiomyopathies. We will summarise pathogenic variants identified in the six genes coding for these proteins and look at their involvement in myopathy and cardiomyopathy. Listing the Minor Allele Frequency (MAF) of these variants in the Genome Aggregation Database (GnomAD) version 3.1 will help to critically re-evaluate pathogenicity based on variant frequency in normal population cohorts.
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30
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Russell B, Solís C. Mechanosignaling pathways alter muscle structure and function by post-translational modification of existing sarcomeric proteins to optimize energy usage. J Muscle Res Cell Motil 2021; 42:367-380. [PMID: 33595762 DOI: 10.1007/s10974-021-09596-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/04/2021] [Indexed: 12/29/2022]
Abstract
A transduced mechanical signal arriving at its destination in muscle alters sarcomeric structure and function. A major question addressed is how muscle mass and tension generation are optimized to match actual performance demands so that little energy is wasted. Three cases for improved energy efficiency are examined: the troponin complex for tuning force production, control of the myosin heads in a resting state, and the Z-disc proteins for sarcomere assembly. On arrival, the regulation of protein complexes is often controlled by post-translational modification (PTM), of which the most common are phosphorylation by kinases, deacetylation by histone deacetylases and ubiquitination by E3 ligases. Another branch of signals acts not through peptide covalent bonding but via ligand interactions (e.g. Ca2+ and phosphoinositide binding). The myosin head and the regulation of its binding to actin by the troponin complex is the best and earliest example of signal destinations that modify myofibrillar contractility. PTMs in the troponin complex regulate both the efficiency of the contractile function to match physiologic demand for work, and muscle mass via protein degradation. The regulation of sarcomere assembly by integration of incoming signaling pathways causing the same PTMs or ligand binding are discussed in response to mechanical loading and unloading by the Z-disc proteins CapZ, α-actinin, telethonin, titin N-termini, and others. Many human mutations that lead to cardiomyopathy and heart disease occur in the proteins discussed above, which often occur at their PTM or ligand binding sites.
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Affiliation(s)
- Brenda Russell
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA.
| | - Christopher Solís
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
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31
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Caloric restriction following early-life high fat-diet feeding represses skeletal muscle TNF in male rats. J Nutr Biochem 2021; 91:108598. [PMID: 33549890 DOI: 10.1016/j.jnutbio.2021.108598] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/03/2020] [Accepted: 01/08/2021] [Indexed: 02/06/2023]
Abstract
Chronic metabolic diseases are on the rise worldwide and their etiology is multifactorial. Among them, inflammatory components like Tumor Necrosis Factor (TNF), contribute to whole-body metabolic impairment. Caloric Restriction (CR) combats metabolic diseases, but how it reduces inflammation remains understudied. We aimed to evaluate the impact of chronic CR on muscle inflammation, in particular TNF. In our study, 4-week old male Sprague-Dawley rats were fed a high-fat diet (HF, 45% Kcal of fat from lard) ad libitum for 3 months. After estimation of their energy requirement (1 month), they were then divided into three groups: HF ad libitum (OL), weight maintenance with AIN93M (9.5% Kcal from fat; ML, 100% of energy requirement), and caloric restriction (CR, AIN93M with 75% of energy requirement). This dietary intervention continued for six months. At this point, rats were sacrificed and gastrocnemius muscle was collected. CR induced a profound shift in fat and lean mass, and decreased growth factor IGF-1. Muscle qPCR analysis showed a marked decrease in inflammation and TNF (premRNA, mRNA, and protein) by CR, accompanied by Tnf promoter DNA hypermethylation. CR increased expression of histone deacetylase Sirt6 and decreased methyltransferase Suv39h1, together with decreased Tnf promoter and coding region binding of NF- κB and C/EBP-β. Following miRNA database mining, qPCR analysis revealed that CR downregulated the proinflammatory miR-19b and increased the anti-inflammatory miR-181a and its known targets. Chronic CR is able to regulate muscle-specific inflammation by targeting the NF-κB pathway as well as transcriptional and post-transcriptional regulation of Tnf gene.
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Pablo Tortola C, Fielitz B, Li Y, Rüdebusch J, Luft FC, Fielitz J. Activation of Tripartite Motif Containing 63 Expression by Transcription Factor EB and Transcription Factor Binding to Immunoglobulin Heavy Chain Enhancer 3 Is Regulated by Protein Kinase D and Class IIa Histone Deacetylases. Front Physiol 2021; 11:550506. [PMID: 33519497 PMCID: PMC7838639 DOI: 10.3389/fphys.2020.550506] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 12/09/2020] [Indexed: 01/07/2023] Open
Abstract
Rationale The ubiquitin–proteasome system (UPS) is responsible for skeletal muscle atrophy. We showed earlier that the transcription factor EB (TFEB) plays a role by increasing E3 ubiquitin ligase muscle really interesting new gene-finger 1(MuRF1)/tripartite motif-containing 63 (TRIM63) expression. MuRF 1 ubiquitinates structural proteins and mediates their UPS-dependent degradation. We now investigated how TFEB-mediated TRIM63 expression is regulated. Objective Because protein kinase D1 (PKD1), histone deacetylase 5 (HDAC5), and TFEB belong to respective families with close structural, regulatory, and functional properties, we hypothesized that these families comprise a network regulating TRIM63 expression. Methods and Results We found that TFEB and transcription factor for immunoglobulin heavy-chain enhancer 3 (TFE3) activate TRIM63 expression. The class IIa HDACs HDAC4, HDAC5, and HDAC7 inhibited this activity. Furthermore, we could map the HDAC5 and TFE3 physical interaction. PKD1, PKD2, and PKD3 reversed the inhibitory effect of all tested class IIa HDACs toward TFEB and TFE3. PKD1 mediated nuclear export of all HDACs and lifted TFEB and TFE3 repression. We also mapped the PKD2 and HDAC5 interaction. We found that the inhibitory effect of PKD1 and PKD2 toward HDAC4, HDAC5, and HDAC7 was mediated by their phosphorylation and 14-3-3 mediated nuclear export. Conclusion TFEB and TFE3 activate TRIM63 expression. Both transcription factors are controlled by HDAC4, HDAC5, HDAC7, and all PKD-family members. We propose that the multilevel PKD/HDAC/TFEB/TFE3 network tightly controls TRIM63 expression.
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Affiliation(s)
- Cristina Pablo Tortola
- Experimental and Clinical Research Center (ECRC), Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Britta Fielitz
- Department of Internal Medicine B, Cardiology, University Medicine Greifswald, Greifswald, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany
| | - Yi Li
- Experimental and Clinical Research Center (ECRC), Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Julia Rüdebusch
- Department of Internal Medicine B, Cardiology, University Medicine Greifswald, Greifswald, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany
| | - Friedrich C Luft
- Experimental and Clinical Research Center (ECRC), Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Jens Fielitz
- Experimental and Clinical Research Center (ECRC), Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Department of Internal Medicine B, Cardiology, University Medicine Greifswald, Greifswald, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany
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Lewis HR, Eminaga S, Gautel M, Avkiran M. Phosphorylation at Serines 157 and 161 Is Necessary for Preserving Cardiac Expression Level and Functions of Sarcomeric Z-Disc Protein Telethonin. Front Physiol 2021; 12:732020. [PMID: 34566695 PMCID: PMC8455888 DOI: 10.3389/fphys.2021.732020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/16/2021] [Indexed: 11/13/2022] Open
Abstract
Aims: In cardiac myocytes, the sarcomeric Z-disc protein telethonin is constitutively bis-phosphorylated at C-terminal residues S157 and S161; however, the functional significance of this phosphorylation is not known. We sought to assess the significance of telethonin phosphorylation in vivo, using a novel knock-in (KI) mouse model generated to express non-phosphorylatable telethonin (Tcap S157/161A). Methods and Results: Tcap S157/161A and wild-type (WT) littermates were characterized by echocardiography at baseline and after sustained β-adrenergic stimulation via isoprenaline infusion. Heart tissues were collected for gravimetric, biochemical, and histological analyses. At baseline, Tcap S157/161A mice did not show any variances in cardiac structure or function compared with WT littermates and mutant telethonin remained localized to the Z-disc. Ablation of telethonin phosphorylation sites resulted in a gene-dosage dependent decrease in the cardiac telethonin protein expression level in mice carrying the S157/161A alleles, without any alteration in telethonin mRNA levels. The proteasome inhibitor MG132 significantly increased the expression level of S157/161A telethonin protein in myocytes from Tcap S157/161A mice, but not telethonin protein in myocytes from WT mice, indicating a role for the ubiquitin-proteasome system in the regulation of telethonin protein expression level. Tcap S157/161A mice challenged with sustained β-adrenergic stimulation via isoprenaline infusion developed cardiac hypertrophy accompanied by mild systolic dysfunction. Furthermore, the telethonin protein expression level was significantly increased in WT mice following isoprenaline stimulation but this response was blunted in Tcap S157/161A mice. Conclusion: Overall, these data reveal that telethonin protein turnover in vivo is regulated in a novel phosphorylation-dependent manner and suggest that C-terminal phosphorylation may protect telethonin against proteasomal degradation and preserve cardiac function during hemodynamic stress. Given that human telethonin C-terminal mutations have been associated with cardiac and skeletal myopathies, further research on their potential impact on phosphorylation-dependent regulation of telethonin protein expression could provide valuable mechanistic insight into those myopathies.
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Affiliation(s)
- Hannah R. Lewis
- School of Cardiovascular Medicine and Sciences, St Thomas’ Hospital, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom
| | - Seda Eminaga
- School of Cardiovascular Medicine and Sciences, St Thomas’ Hospital, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom
| | - Mathias Gautel
- School of Basic and Medical Biosciences, Guy’s Hospital, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom
| | - Metin Avkiran
- School of Cardiovascular Medicine and Sciences, St Thomas’ Hospital, King’s College London British Heart Foundation Centre of Research Excellence, London, United Kingdom
- *Correspondence: Metin Avkiran,
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Tauffenberger A, Magistretti PJ. Reactive Oxygen Species: Beyond Their Reactive Behavior. Neurochem Res 2021; 46:77-87. [PMID: 33439432 PMCID: PMC7829243 DOI: 10.1007/s11064-020-03208-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 11/02/2020] [Accepted: 12/15/2020] [Indexed: 12/13/2022]
Abstract
Cellular homeostasis plays a critical role in how an organism will develop and age. Disruption of this fragile equilibrium is often associated with health degradation and ultimately, death. Reactive oxygen species (ROS) have been closely associated with health decline and neurological disorders, such as Alzheimer's disease or Parkinson's disease. ROS were first identified as by-products of the cellular activity, mainly mitochondrial respiration, and their high reactivity is linked to a disruption of macromolecules such as proteins, lipids and DNA. More recent research suggests more complex function of ROS, reaching far beyond the cellular dysfunction. ROS are active actors in most of the signaling cascades involved in cell development, proliferation and survival, constituting important second messengers. In the brain, their impact on neurons and astrocytes has been associated with synaptic plasticity and neuron survival. This review provides an overview of ROS function in cell signaling in the context of aging and degeneration in the brain and guarding the fragile balance between health and disease.
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Affiliation(s)
- Arnaud Tauffenberger
- King Abdullah University of Science and Technology, Thuwal, 23955, Kingdom of Saudi Arabia.
| | - Pierre J Magistretti
- King Abdullah University of Science and Technology, Thuwal, 23955, Kingdom of Saudi Arabia.
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35
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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: 162] [Impact Index Per Article: 54.0] [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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Abstract
A long-standing question, particularly in physiotherapy and sports medicine, is whether time of day affects muscle metabolism and hence growth, either intrinsically or in response to exercise or nutrition. Answers would help to identify the best time of day to exercise, build muscle, and prevent aging- or disease-related sarcopenia. Here, we address this question in live zebrafish myotome in vivo, without interference from other circadian oscillations such as locomotor activity and food intake. We show that active muscle anabolizes more in the day and grows faster, while catabolizing more at night and growing slower. Such day/night differences remain in inactive muscle but disappear after clock disruption. We conclude that muscles display circadian differences in growth independent of activity and feeding. Muscle tissue shows diurnal variations in function, physiology, and metabolism. Whether such variations are dependent on the circadian clock per se or are secondary to circadian differences in physical activity and feeding pattern is unclear. By measuring muscle growth over 12-h periods in live prefeeding larval zebrafish, we show that muscle grows more during day than night. Expression of dominant negative CLOCK (ΔCLK), which inhibits molecular clock function, ablates circadian differences and reduces muscle growth. Inhibition of muscle contraction reduces growth in both day and night, but does not ablate the day/night difference. The circadian clock and physical activity are both required to promote higher muscle protein synthesis during the day compared to night, whereas markers of protein degradation, murf messenger RNAs, are higher at night. Proteasomal inhibitors increase muscle growth at night, irrespective of physical activity, but have no effect during the day. Although physical activity enhances TORC1 activity, and the TORC1 inhibitor rapamycin inhibits clock-driven daytime growth, no effect on muscle growth at night was detected. Importantly, day/night differences in 1) muscle growth, 2) protein synthesis, and 3) murf expression all persist in entrained larvae under free-running constant conditions, indicating circadian drive. Removal of circadian input by exposure to either permanent darkness or light leads to suboptimal muscle growth. We conclude that diurnal variations in muscle growth and metabolism are a circadian property that is independent of, but augmented by, physical activity, at least during development.
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Network integration and modelling of dynamic drug responses at multi-omics levels. Commun Biol 2020; 3:573. [PMID: 33060801 PMCID: PMC7567116 DOI: 10.1038/s42003-020-01302-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 09/14/2020] [Indexed: 12/25/2022] Open
Abstract
Uncovering cellular responses from heterogeneous genomic data is crucial for molecular medicine in particular for drug safety. This can be realized by integrating the molecular activities in networks of interacting proteins. As proof-of-concept we challenge network modeling with time-resolved proteome, transcriptome and methylome measurements in iPSC-derived human 3D cardiac microtissues to elucidate adverse mechanisms of anthracycline cardiotoxicity measured with four different drugs (doxorubicin, epirubicin, idarubicin and daunorubicin). Dynamic molecular analysis at in vivo drug exposure levels reveal a network of 175 disease-associated proteins and identify common modules of anthracycline cardiotoxicity in vitro, related to mitochondrial and sarcomere function as well as remodeling of extracellular matrix. These in vitro-identified modules are transferable and are evaluated with biopsies of cardiomyopathy patients. This to our knowledge most comprehensive study on anthracycline cardiotoxicity demonstrates a reproducible workflow for molecular medicine and serves as a template for detecting adverse drug responses from complex omics data. Using a network propagation approach with integrated multi-omic data, Selevsek et al. develop a reproducible workflow for identifying drug toxicity effects in cellular systems. This is demonstrated with the analysis of anthracycline cardiotoxicity in cardiac microtissues under the effect of multiple drugs.
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38
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Peris-Moreno D, Taillandier D, Polge C. MuRF1/TRIM63, Master Regulator of Muscle Mass. Int J Mol Sci 2020; 21:ijms21186663. [PMID: 32933049 PMCID: PMC7555135 DOI: 10.3390/ijms21186663] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 02/07/2023] Open
Abstract
The E3 ubiquitin ligase MuRF1/TRIM63 was identified 20 years ago and suspected to play important roles during skeletal muscle atrophy. Since then, numerous studies have been conducted to decipher the roles, molecular mechanisms and regulation of this enzyme. This revealed that MuRF1 is an important player in the skeletal muscle atrophy process occurring during catabolic states, making MuRF1 a prime candidate for pharmacological treatments against muscle wasting. Indeed, muscle wasting is an associated event of several diseases (e.g., cancer, sepsis, diabetes, renal failure, etc.) and negatively impacts the prognosis of patients, which has stimulated the search for MuRF1 inhibitory molecules. However, studies on MuRF1 cardiac functions revealed that MuRF1 is also cardioprotective, revealing a yin and yang role of MuRF1, being detrimental in skeletal muscle and beneficial in the heart. This review discusses data obtained on MuRF1, both in skeletal and cardiac muscles, over the past 20 years, regarding the structure, the regulation, the location and the different functions identified, and the first inhibitors reported, and aim to draw the picture of what is known about MuRF1. The review also discusses important MuRF1 characteristics to consider for the design of future drugs to maintain skeletal muscle mass in patients with different pathologies.
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Under construction: The dynamic assembly, maintenance, and degradation of the cardiac sarcomere. J Mol Cell Cardiol 2020; 148:89-102. [PMID: 32920010 DOI: 10.1016/j.yjmcc.2020.08.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/20/2020] [Accepted: 08/22/2020] [Indexed: 12/11/2022]
Abstract
The sarcomere is the basic contractile unit of striated muscle and is a highly ordered protein complex with the actin and myosin filaments at its core. Assembling the sarcomere constituents into this organized structure in development, and with muscle growth as new sarcomeres are built, is a complex process coordinated by numerous factors. Once assembled, the sarcomere requires constant maintenance as its continuous contraction is accompanied by elevated mechanical, thermal, and oxidative stress, which predispose proteins to misfolding and toxic aggregation. To prevent protein misfolding and maintain sarcomere integrity, the sarcomere is monitored by an assortment of protein quality control (PQC) mechanisms. The need for effective PQC is heightened in cardiomyocytes which are terminally differentiated and must survive for many years while preserving optimal mechanical output. To prevent toxic protein aggregation, molecular chaperones stabilize denatured sarcomere proteins and promote their refolding. However, when old and misfolded proteins cannot be salvaged by chaperones, they must be recycled via degradation pathways: the calpain and ubiquitin-proteasome systems, which operate under basal conditions, and the stress-responsive autophagy-lysosome pathway. Mutations to and deficiency of the molecular chaperones and associated factors charged with sarcomere maintenance commonly lead to sarcomere structural disarray and the progression of heart disease, highlighting the necessity of effective sarcomere PQC for maintaining cardiac function. This review focuses on the dynamic regulation of assembly and turnover at the sarcomere with an emphasis on the chaperones involved in these processes and describes the alterations to chaperones - through mutations and deficient expression - implicated in disease progression to heart failure.
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Abstract
Muscle stiffness, muscle elasticity and explosive strength are the main components of athletes' performance and they show a sex-based as well as ethnicity variation. Muscle stiffness is thought to be one of the risk factors associated with sports injuries and is less common in females than in males. These observations may be explained by circulating levels of sex hormones and their specific receptors. It has been shown that higher levels of estrogen are associated with lower muscle stiffness responsible for suppression of collagen synthesis. It is thought that these properties, at least in part, depend on genetic factors. Particularly, the gene encoding estrogen receptor 1 (ESR1) is one of the candidates that may be associated with muscle stiffness. Muscle elasticity increases with aging and there is evidence suggesting that titin (encoded by the TTN gene), a protein that is expressed in cardiac and skeletal muscles, is one of the factors responsible for elastic properties of the muscles. Mutations in the TTN gene result in some types of muscular dystrophy or cardiomyopathy. In this context, TTN may be regarded as a promising candidate for studying the elastic properties of muscles in athletes. The physiological background of explosive strength depends not only on the muscle architecture and muscle fiber composition, but also on the central nervous system and functionality of neuromuscular units. These properties are, at least partly, genetically determined. In this context, the ACTN3 gene code for α-actinin 3 has been widely researched.
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41
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Heras G, Namuduri AV, Traini L, Shevchenko G, Falk A, Bergström Lind S, Jia M, Tian G, Gastaldello S. Muscle RING-finger protein-1 (MuRF1) functions and cellular localization are regulated by SUMO1 post-translational modification. J Mol Cell Biol 2020; 11:356-370. [PMID: 29868881 PMCID: PMC7727263 DOI: 10.1093/jmcb/mjy036] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/25/2018] [Accepted: 06/01/2018] [Indexed: 01/02/2023] Open
Abstract
The muscle RING-finger protein-1 (MuRF1) is an E3 ubiquitin ligase expressed in skeletal and cardiac muscle tissues and it plays important roles in muscle remodeling. Upregulation of MuRF1 gene transcription participates in skeletal muscle atrophy, on contrary downregulation of protein expression leads to cardiac hypertrophy. MuRF1 gene point mutations have been found to generate protein aggregate myopathies defined as muscle disorder characterized by protein accumulation in muscle fibers. We have discovered that MuRF1 turned out to be also a target for a new post-translational modification arbitrated by conjugation of SUMO1 and it is mediated by the SUMO ligases E2 UBC9 and the E3 PIASγ/4. SUMOylation takes place at lysine 238 localized at the second coiled-coil protein domain that is required for efficient substrate interaction for polyubiquitination. We provided evidence that SUMOylation is essential for MuRF1 nuclear translocation and its mitochondria accumulation is enhanced in hyperglycemic conditions delivering a stabilization of the overall SUMOylated proteins in cultured myocytes. Thus, our findings add this SUMO1 post-translational modification as a new concept to understand muscle disorders related to the defect in MuRF1 activity.
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Affiliation(s)
- Gabriel Heras
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavägen 9, Quarter B5, Stockholm, Sweden
| | - Arvind Venkat Namuduri
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavägen 9, Quarter B5, Stockholm, Sweden
| | - Leonardo Traini
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavägen 9, Quarter B5, Stockholm, Sweden
| | - Ganna Shevchenko
- Department of Chemistry-BMC, Analytical Chemistry, Uppsala University, Uppsala, Sweden
| | - Alexander Falk
- Department of Chemistry-BMC, Analytical Chemistry, Uppsala University, Uppsala, Sweden
| | - Sara Bergström Lind
- Department of Chemistry-BMC, Analytical Chemistry, Uppsala University, Uppsala, Sweden
| | - Mi Jia
- Precision Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai, China
| | - Geng Tian
- Precision Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai, China
| | - Stefano Gastaldello
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavägen 9, Quarter B5, Stockholm, Sweden.,Precision Medicine and Pharmacy Research Center, Binzhou Medical University, Yantai, China
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Chen Y, Jin J. The application of ubiquitin ligases in the PROTAC drug design. Acta Biochim Biophys Sin (Shanghai) 2020; 52:776-790. [PMID: 32506133 DOI: 10.1093/abbs/gmaa053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 06/25/2019] [Accepted: 06/26/2019] [Indexed: 12/13/2022] Open
Abstract
Protein ubiquitylation plays important roles in many biological activities. Protein ubiquitylation is a unique process that is mainly controlled by ubiquitin ligases. The ubiquitin-proteasome system (UPS) is the main process to degrade short-lived and unwanted proteins in eukaryotes. Many components in the UPS are attractive drug targets. Recent studies indicated that ubiquitin ligases can be employed as tools in proteolysis-targeting chimeras (PROTACs) for drug discovery. In this review article, we will discuss the recent progress of the application of ubiquitin ligases in the PROTAC drug design. We will also discuss advantages and existing problems of PROTACs. Moreover, we will propose a few principles for selecting ubiquitin ligases in PROTAC applications.
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Affiliation(s)
- Yilin Chen
- Life Science Institute, Zhejiang University, Hangzhou 310058, China
| | - Jianping Jin
- Life Science Institute, Zhejiang University, Hangzhou 310058, China
- Zhejiang Provincial Key Laboratory for Drug Evaluation and Clinical Research, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
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Emerging Strategies Targeting Catabolic Muscle Stress Relief. Int J Mol Sci 2020; 21:ijms21134681. [PMID: 32630118 PMCID: PMC7369951 DOI: 10.3390/ijms21134681] [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] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 12/21/2022] Open
Abstract
Skeletal muscle wasting represents a common trait in many conditions, including aging, cancer, heart failure, immobilization, and critical illness. Loss of muscle mass leads to impaired functional mobility and severely impedes the quality of life. At present, exercise training remains the only proven treatment for muscle atrophy, yet many patients are too ill, frail, bedridden, or neurologically impaired to perform physical exertion. The development of novel therapeutic strategies that can be applied to an in vivo context and attenuate secondary myopathies represents an unmet medical need. This review discusses recent progress in understanding the molecular pathways involved in regulating skeletal muscle wasting with a focus on pro-catabolic factors, in particular, the ubiquitin-proteasome system and its activating muscle-specific E3 ligase RING-finger protein 1 (MuRF1). Mechanistic progress has provided the opportunity to design experimental therapeutic concepts that may affect the ubiquitin-proteasome system and prevent subsequent muscle wasting, with novel advances made in regards to nutritional supplements, nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) inhibitors, myostatin antibodies, β2 adrenergic agonists, and small-molecules interfering with MuRF1, which all emerge as a novel in vivo treatment strategies for muscle wasting.
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Nguyen T, Bowen TS, Augstein A, Schauer A, Gasch A, Linke A, Labeit S, Adams V. Expression of MuRF1 or MuRF2 is essential for the induction of skeletal muscle atrophy and dysfunction in a murine pulmonary hypertension model. Skelet Muscle 2020; 10:12. [PMID: 32340625 PMCID: PMC7184701 DOI: 10.1186/s13395-020-00229-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/13/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pulmonary hypertension leads to right ventricular heart failure and ultimately to cardiac cachexia. Cardiac cachexia induces skeletal muscles atrophy and contractile dysfunction. MAFbx and MuRF1 are two key proteins that have been implicated in chronic muscle atrophy of several wasting states. METHODS Monocrotaline (MCT) was injected over eight weeks into mice to establish pulmonary hypertension as a murine model for cardiac cachexia. The effects on skeletal muscle atrophy, myofiber force, and selected muscle proteins were evaluated in wild-type (WT), MuRF1, and MuRF2-KO mice by determining muscle weights, in vitro muscle force and enzyme activities in soleus and tibialis anterior (TA) muscle. RESULTS In WT, MCT treatment induced wasting of soleus and TA mass, loss of myofiber force, and depletion of citrate synthase (CS), creatine kinase (CK), and malate dehydrogenase (MDH) (all key metabolic enzymes). This suggests that the murine MCT model is useful to mimic peripheral myopathies as found in human cardiac cachexia. In MuRF1 and MuRF2-KO mice, soleus and TA muscles were protected from atrophy, contractile dysfunction, while metabolic enzymes were not lowered in MuRF1 or MuRF2-KO mice. Furthermore, MuRF2 expression was lower in MuRF1KO mice when compared to C57BL/6 mice. CONCLUSIONS In addition to MuRF1, inactivation of MuRF2 also provides a potent protection from peripheral myopathy in cardiac cachexia. The protection of metabolic enzymes in both MuRF1KO and MuRF2KO mice as well as the dependence of MuRF2 expression on MuRF1 suggests intimate relationships between MuRF1 and MuRF2 during muscle atrophy signaling.
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Affiliation(s)
- Thanh Nguyen
- University Clinic of Cardiology, Heart Center Leipzig, Leipzig, Germany
| | - T Scott Bowen
- School of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Antje Augstein
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - Antje Schauer
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - Alexander Gasch
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Axel Linke
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - Siegfried Labeit
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany.,Myomedix GmbH, Neckargemünd, Germany
| | - Volker Adams
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany.
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Agarwal M, Sharma A, Kumar P, Kumar A, Bharadwaj A, Saini M, Kardon G, Mathew SJ. Myosin heavy chain-embryonic regulates skeletal muscle differentiation during mammalian development. Development 2020; 147:dev184507. [PMID: 32094117 PMCID: PMC7157585 DOI: 10.1242/dev.184507] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 02/12/2020] [Indexed: 12/12/2022]
Abstract
Myosin heavy chain-embryonic (MyHC-emb) is a skeletal muscle-specific contractile protein expressed during muscle development. Mutations in MYH3, the gene encoding MyHC-emb, lead to Freeman-Sheldon and Sheldon-Hall congenital contracture syndromes. Here, we characterize the role of MyHC-emb during mammalian development using targeted mouse alleles. Germline loss of MyHC-emb leads to neonatal and postnatal alterations in muscle fiber size, fiber number, fiber type and misregulation of genes involved in muscle differentiation. Deletion of Myh3 during embryonic myogenesis leads to the depletion of the myogenic progenitor cell pool and an increase in the myoblast pool, whereas fetal myogenesis-specific deletion of Myh3 causes the depletion of both myogenic progenitor and myoblast pools. We reveal that the non-cell-autonomous effect of MyHC-emb on myogenic progenitors and myoblasts is mediated by the fibroblast growth factor (FGF) signaling pathway, and exogenous FGF rescues the myogenic differentiation defects upon loss of MyHC-emb function in vitro Adult Myh3 null mice exhibit scoliosis, a characteristic phenotype exhibited by individuals with Freeman-Sheldon and Sheldon-Hall congenital contracture syndrome. Thus, we have identified MyHC-emb as a crucial myogenic regulator during development, performing dual cell-autonomous and non-cell-autonomous functions.This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Megha Agarwal
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
- Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Akashi Sharma
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
- KIIT University, Patia, Bhubaneswar, 751024, Odisha, India
| | - Pankaj Kumar
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
- Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Amit Kumar
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
| | - Anushree Bharadwaj
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
| | - Masum Saini
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
| | - Gabrielle Kardon
- Department of Human Genetics, University of Utah, 15 N 2030 E, Salt Lake City, UT 84112, USA
| | - Sam J Mathew
- Developmental Genetics Laboratory, Regional Centre for Biotechnology (RCB), NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad, 121001 Haryana, India
- Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
- KIIT University, Patia, Bhubaneswar, 751024, Odisha, India
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46
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Chomphoo S, Sakagami H, Kondo H, Hipkaeo W. Discrete localization patterns of Arf6, and its activators EFA6A and BRAG2, and its effector PIP5kinaseγ on myofibrils of myotubes and plasma membranes of myoblasts in developing skeletal muscles of mice. Acta Histochem 2020; 122:151513. [PMID: 32059926 DOI: 10.1016/j.acthis.2020.151513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/27/2022]
Abstract
Arf6 (ADP ribosylation factor 6), activated by Arf-GEF (guanine nucleoside exchange factor), is involved in the membrane trafficking and actin-remodeling which are critical for maintenance of cell organization and activity and for fusion of myoblasts to form myotubes/myofibers. EFA6A (exchange factor for Arf6 type A) and BRAG2 (brefeldin A-resistant Arf-GEF 2) represent members of discrete subfamilies of Arf-GEF, while PIP5Kγ (phosphatidylinositol4-phosphate5-kinase γ) produces PI 4,5-bisphosphate (PIP2) and it is target for Arf6. In the present study, immunoreactive bands for Arf6, EFA6A, BRAG2 and PIP5Kγ were detected in immunoblots of skeletal muscle homogenates of mice at E18D (embryonic day 18), while the bands for Arf6, EFA6A and PIP5Kγ were reduced in density and no significant bands for BRAG2 were discerned at P1D (postnatal 1 day). No immunoblot bands for any of the molecules were eventually detected in skeletal fibers of adult mice. Immunoreactivities for endogenous Arf6, EFA6A and PIP5Kγ were visualized using immuno-light microscopy localized as periodic striations running perpendicular to the longitudinal axes of skeletal muscle fibers of mice at E18D and P1D. All the striations were co-immunoreactive for β-actin in double immunofluorescence microscopy, and the immunoreactivities were confined to thin myofilaments at sarcomeric I-domains in immuno-electron microscopy. On the other hand, immunoreactivities for Arf6, BRAG2 and PIP5Kγ were conspicuous on plasmalemma of myoblasts at E14D, while immunoreactivity for EFA6A was already distinct in striations perpendicular to myofibrils in myotubes at E14D. The present findings suggest three possibilities: involvement of EFA6A-activated Arf6 together with PIP5Kγ in maturation of myofibrils, movement of Arf6 and PIP5Kγ from the plasmalemma of myoblasts to myofibrils of myotubes, and that of BRAG2 to the cytoplasm of myotubes; and further a function of EFA6A independent of the activation of Arf6 in immature myofibrils. In addition, the involvement of Arf6, BRAG2 and PIP5Kγ in the fusion of myoblasts into myotubes was supported by the present finding.
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Affiliation(s)
- Surang Chomphoo
- Electron Microscopy Unit, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
| | - Hiroyuki Sakagami
- Department of Anatomy, School of Medicine, Kitasato University, Sagamihara, Japan
| | - Hisatake Kondo
- Electron Microscopy Unit, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; Department of Anatomy, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Wiphawi Hipkaeo
- Electron Microscopy Unit, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
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47
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Prill K, Dawson JF. Assembly and Maintenance of Sarcomere Thin Filaments and Associated Diseases. Int J Mol Sci 2020; 21:E542. [PMID: 31952119 PMCID: PMC7013991 DOI: 10.3390/ijms21020542] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/06/2020] [Accepted: 01/12/2020] [Indexed: 12/22/2022] Open
Abstract
Sarcomere assembly and maintenance are essential physiological processes required for cardiac and skeletal muscle function and organism mobility. Over decades of research, components of the sarcomere and factors involved in the formation and maintenance of this contractile unit have been identified. Although we have a general understanding of sarcomere assembly and maintenance, much less is known about the development of the thin filaments and associated factors within the sarcomere. In the last decade, advancements in medical intervention and genome sequencing have uncovered patients with novel mutations in sarcomere thin filaments. Pairing this sequencing with reverse genetics and the ability to generate patient avatars in model organisms has begun to deepen our understanding of sarcomere thin filament development. In this review, we provide a summary of recent findings regarding sarcomere assembly, maintenance, and disease with respect to thin filaments, building on the previous knowledge in the field. We highlight debated and unknown areas within these processes to clearly define open research questions.
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Affiliation(s)
| | - John F. Dawson
- Centre for Cardiovascular Investigations, Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada;
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48
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Mugahid DA, Sengul TG, You X, Wang Y, Steil L, Bergmann N, Radke MH, Ofenbauer A, Gesell-Salazar M, Balogh A, Kempa S, Tursun B, Robbins CT, Völker U, Chen W, Nelson L, Gotthardt M. Proteomic and Transcriptomic Changes in Hibernating Grizzly Bears Reveal Metabolic and Signaling Pathways that Protect against Muscle Atrophy. Sci Rep 2019; 9:19976. [PMID: 31882638 PMCID: PMC6934745 DOI: 10.1038/s41598-019-56007-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/05/2019] [Indexed: 12/31/2022] Open
Abstract
Muscle atrophy is a physiological response to disuse and malnutrition, but hibernating bears are largely resistant to this phenomenon. Unlike other mammals, they efficiently reabsorb amino acids from urine, periodically activate muscle contraction, and their adipocytes differentially responds to insulin. The contribution of myocytes to the reduced atrophy remains largely unknown. Here we show how metabolism and atrophy signaling are regulated in skeletal muscle of hibernating grizzly bear. Metabolic modeling of proteomic changes suggests an autonomous increase of non-essential amino acids (NEAA) in muscle and treatment of differentiated myoblasts with NEAA is sufficient to induce hypertrophy. Our comparison of gene expression in hibernation versus muscle atrophy identified several genes differentially regulated during hibernation, including Pdk4 and Serpinf1. Their trophic effects extend to myoblasts from non-hibernating species (including C. elegans), as documented by a knockdown approach. Together, these changes reflect evolutionary favored adaptations that, once translated to the clinics, could help improve atrophy treatment.
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Affiliation(s)
- D A Mugahid
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - T G Sengul
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - X You
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Y Wang
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - L Steil
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - N Bergmann
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - M H Radke
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - A Ofenbauer
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - M Gesell-Salazar
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - A Balogh
- Experimental and Clinical Research Center, Charité & Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - S Kempa
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - B Tursun
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - C T Robbins
- School of the Environment and School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - U Völker
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Greifswald, Greifswald, Germany
| | - W Chen
- Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - L Nelson
- College of Veterinary Medicine and Department of Veterinary Clinical Science, Washington State University, Pullman, Washington, USA
| | - M Gotthardt
- Neuromuscular and Cardiovascular Cell Biology, Max Delbrück Center for Molecular Medicine, Berlin, Germany. .,Charité Universitätsmedizin Berlin, Berlin, Germany. .,DZHK (German Center for Cardiovascular Research), partner site Berlin, Berlin, Germany.
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49
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Heliste J, Chheda H, Paatero I, Salminen TA, Akimov Y, Paavola J, Elenius K, Aittokallio T. Genetic and functional implications of an exonic TRIM55 variant in heart failure. J Mol Cell Cardiol 2019; 138:222-233. [PMID: 31866377 DOI: 10.1016/j.yjmcc.2019.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 12/09/2019] [Accepted: 12/12/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND To tackle the missing heritability of sporadic heart failure, we screened for novel heart failure-associated genetic variants in the Finnish population and functionally characterized a novel variant in vitro and in vivo. METHODS AND RESULTS Heart failure-associated variants were screened in genotyping array data of the FINRISK study, consisting of 994 cases and 20,118 controls. Based on logistic regression analysis, a potentially damaging variant in TRIM55 (rs138811034), encoding an E140K variant, was selected for validations. In HL-1 cardiomyocytes, we used CRISPR/Cas9 technology to introduce the variant in the endogenous locus, and additionally TRIM55 wildtype or E140K was overexpressed from plasmid. Functional responses were profiled using whole-genome RNA sequencing, RT-PCR and Western analyses, cell viability and cell cycle assays and cell surface area measurements. In zebrafish embryos, cardiac contractility was measured using videomicroscopy after CRISPR-mediated knockout of trim55a or plasmid overexpression of TRIM55 WT or E140K. Genes related to muscle contraction and cardiac stress were highly regulated in Trim55 E140K/- cardiomyocytes. When compared to the WT/WT cells, the variant cells demonstrated reduced viability, significant hypertrophic response to isoproterenol, p21 protein overexpression and impaired cell cycle progression. In zebrafish embryos, the deletion of trim55a or overexpression of TRIM55 E140K reduced cardiac contractility as compared to embryos with wildtype genotype or overexpression of WT TRIM55, respectively. CONCLUSIONS A previously uncharacterized TRIM55 E140K variant demonstrated a number of functional implications for cardiomyocyte functions in vitro and in vivo. These findings suggest a novel role for TRIM55 polymorphism in predisposing to heart failure.
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Affiliation(s)
- Juho Heliste
- Institute for Molecular Medicine Finland, FIMM, University of Helsinki, Biomedicum 2U, Tukholmankatu 8, FI-00290 Helsinki, Finland; Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20014 Turku, Finland; Turku Doctoral Programme of Molecular Medicine, University of Turku, Turku, Finland
| | - Himanshu Chheda
- Institute for Molecular Medicine Finland, FIMM, University of Helsinki, Biomedicum 2U, Tukholmankatu 8, FI-00290 Helsinki, Finland
| | - Ilkka Paatero
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, Tykistökatu 6, FI-20520 Turku, Finland
| | - Tiina A Salminen
- Structural Bioinformatics Laboratory, Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Tykistökatu 6, FI-20520 Turku, Finland
| | - Yevhen Akimov
- Institute for Molecular Medicine Finland, FIMM, University of Helsinki, Biomedicum 2U, Tukholmankatu 8, FI-00290 Helsinki, Finland
| | - Jere Paavola
- Unit of Cardiovascular Research, Minerva Foundation Institute for Medical Research, Biomedicum 2U, Tukholmankatu 8, FI-00290 Helsinki, Finland
| | - Klaus Elenius
- Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20014 Turku, Finland; Turku Bioscience Centre, University of Turku and Åbo Akademi University, Tykistökatu 6, FI-20520 Turku, Finland; Medicity Research Laboratories, University of Turku, Tykistökatu 6, FI-20520 Turku, Finland; Department of Oncology, Turku University Hospital, PO Box 52, FI-20521 Turku, Finland
| | - Tero Aittokallio
- Institute for Molecular Medicine Finland, FIMM, University of Helsinki, Biomedicum 2U, Tukholmankatu 8, FI-00290 Helsinki, Finland; Department of Mathematics and Statistics, University of Turku, Vesilinnantie 5, FI-20014 Turku, Finland.
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50
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Adams V, Bowen TS, Werner S, Barthel P, Amberger C, Konzer A, Graumann J, Sehr P, Lewis J, Provaznik J, Benes V, Büttner P, Gasch A, Mangner N, Witt CC, Labeit D, Linke A, Labeit S. Small-molecule-mediated chemical knock-down of MuRF1/MuRF2 and attenuation of diaphragm dysfunction in chronic heart failure. J Cachexia Sarcopenia Muscle 2019; 10:1102-1115. [PMID: 31140761 PMCID: PMC6818456 DOI: 10.1002/jcsm.12448] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Chronic heart failure (CHF) leads to diaphragm myopathy that significantly impairs quality of life and worsens prognosis. In this study, we aimed to assess the efficacy of a recently discovered small-molecule inhibitor of MuRF1 in treating CHF-induced diaphragm myopathy and loss of contractile function. METHODS Myocardial infarction was induced in mice by ligation of the left anterior descending coronary artery. Sham-operated animals (sham) served as controls. One week post-left anterior descending coronary artery ligation animals were randomized into two groups-one group was fed control rodent chow, whereas the other group was fed a diet containing 0.1% of the compound ID#704946-a recently described MuRF1-interfering small molecule. Echocardiography confirmed development of CHF after 10 weeks. Functional and molecular analysis of the diaphragm was subsequently performed. RESULTS Chronic heart failure induced diaphragm fibre atrophy and contractile dysfunction by ~20%, as well as decreased activity of enzymes involved in mitochondrial energy production (P < 0.05). Treatment with compound ID#704946 in CHF mice had beneficial effects on the diaphragm: contractile function was protected, while mitochondrial enzyme activity and up-regulation of the MuRF1 and MuRF2 was attenuated after infarct. CONCLUSIONS Our murine CHF model presented with diaphragm fibre atrophy, impaired contractile function, and reduced mitochondrial enzyme activities. Compound ID#704946 rescued from this partially, possibly by targeting MuRF1/MuRF2. However, at this stage of our study, we refrain to claim specific mechanism(s) and targets of compound ID#704946, because the nature of changes after 12 weeks of feeding is likely to be complex and is not necessarily caused by direct mechanistic effects.
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Affiliation(s)
- Volker Adams
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - T Scott Bowen
- School of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Sarah Werner
- University Clinic of Cardiology, Heart Center Leipzig, Leipzig, Germany
| | - Peggy Barthel
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | | | - Anne Konzer
- Scientific Service Group Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,German Centre for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Rhine-Main, Germany
| | - Johannes Graumann
- Scientific Service Group Biomolecular Mass Spectrometry, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,German Centre for Cardiovascular Research (DZHK), Partner Site Rhine-Main, Rhine-Main, Germany
| | - Peter Sehr
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Joe Lewis
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jan Provaznik
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Vladimir Benes
- European Molecular Biology Laboratory, Heidelberg, Germany
| | - Petra Büttner
- University Clinic of Cardiology, Heart Center Leipzig, Leipzig, Germany
| | - Alexander Gasch
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Norman Mangner
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - Christian C Witt
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Dittmar Labeit
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany.,Myomedix GmbH, Neckargemünd, Germany
| | - Axel Linke
- Laboratory of Molecular and Experimental Cardiology, TU Dresden, Heart Center Dresden, Dresden, Germany
| | - Siegfried Labeit
- Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany.,Myomedix GmbH, Neckargemünd, Germany
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