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Falcetta D, Quirim S, Cocchiararo I, Chabry F, Théodore M, Stiefvater A, Lin S, Tintignac L, Ivanek R, Kinter J, Rüegg MA, Sinnreich M, Castets P. CaMKIIβ deregulation contributes to neuromuscular junction destabilization in Myotonic Dystrophy type I. Skelet Muscle 2024; 14:11. [PMID: 38769542 PMCID: PMC11106974 DOI: 10.1186/s13395-024-00345-3] [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: 02/11/2024] [Accepted: 05/13/2024] [Indexed: 05/22/2024] Open
Abstract
BACKGROUND Myotonic Dystrophy type I (DM1) is the most common muscular dystrophy in adults. Previous reports have highlighted that neuromuscular junctions (NMJs) deteriorate in skeletal muscle from DM1 patients and mouse models thereof. However, the underlying pathomechanisms and their contribution to muscle dysfunction remain unknown. METHODS We compared changes in NMJs and activity-dependent signalling pathways in HSALR and Mbnl1ΔE3/ΔE3 mice, two established mouse models of DM1. RESULTS Muscle from DM1 mouse models showed major deregulation of calcium/calmodulin-dependent protein kinases II (CaMKIIs), which are key activity sensors regulating synaptic gene expression and acetylcholine receptor (AChR) recycling at the NMJ. Both mouse models exhibited increased fragmentation of the endplate, which preceded muscle degeneration. Endplate fragmentation was not accompanied by changes in AChR turnover at the NMJ. However, the expression of synaptic genes was up-regulated in mutant innervated muscle, together with an abnormal accumulation of histone deacetylase 4 (HDAC4), a known target of CaMKII. Interestingly, denervation-induced increase in synaptic gene expression and AChR turnover was hampered in DM1 muscle. Importantly, CaMKIIβ/βM overexpression normalized endplate fragmentation and synaptic gene expression in innervated Mbnl1ΔE3/ΔE3 muscle, but it did not restore denervation-induced synaptic gene up-regulation. CONCLUSIONS Our results indicate that CaMKIIβ-dependent and -independent mechanisms perturb synaptic gene regulation and muscle response to denervation in DM1 mouse models. Changes in these signalling pathways may contribute to NMJ destabilization and muscle dysfunction in DM1 patients.
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Affiliation(s)
- Denis Falcetta
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, Geneva, CH-1211, Switzerland
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
- Biozentrum, University of Basel, Spitalstrasse 41, Basel, CH-4056, Switzerland
| | - Sandrine Quirim
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, Geneva, CH-1211, Switzerland
| | - Ilaria Cocchiararo
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, Geneva, CH-1211, Switzerland
| | - Florent Chabry
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, Geneva, CH-1211, Switzerland
| | - Marine Théodore
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
| | - Adeline Stiefvater
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
| | - Shuo Lin
- Biozentrum, University of Basel, Spitalstrasse 41, Basel, CH-4056, Switzerland
| | - Lionel Tintignac
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
| | - Robert Ivanek
- Department of Biomedicine, University Hospital and University of Basel, Hebelstrasse 20, Basel, CH-4053, Switzerland
- Swiss Institute of Bioinformatics, Hebelstrasse 20, Basel, CH-4053, Switzerland
| | - Jochen Kinter
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
| | - Markus A Rüegg
- Biozentrum, University of Basel, Spitalstrasse 41, Basel, CH-4056, Switzerland
| | - Michael Sinnreich
- Neuromuscular Research Group, Departments of Neurology and Biomedicine, University and University Hospital Basel, Klingelbergstrasse 50/70, Basel, CH-4056, Switzerland
| | - Perrine Castets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, Geneva, CH-1211, Switzerland.
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Uda M, Yoshihara T, Ichinoseki‐Sekine N, Baba T. Effects of hindlimb unloading on the mevalonate and mechanistic target of rapamycin complex 1 signaling pathways in a fast-twitch muscle in rats. Physiol Rep 2024; 12:e15969. [PMID: 38453353 PMCID: PMC10920058 DOI: 10.14814/phy2.15969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 02/16/2024] [Accepted: 02/22/2024] [Indexed: 03/09/2024] Open
Abstract
Fast-twitch muscles are less susceptible to disuse atrophy, activate the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway, and increase protein synthesis under prolonged muscle disuse conditions. However, the mechanism underlying prolonged muscle disuse-induced mTORC1 signaling activation remains unclear. The mevalonate pathway activates the mTORC1 signaling pathway via the prenylation and activation of Ras homolog enriched in brain (Rheb). Therefore, we investigated the effects of hindlimb unloading (HU) for 14 days on the mevalonate and mTORC1 signaling pathways in the plantaris muscle, a fast-twitch muscle, in adult male rats. Rats were divided into HU and control groups. The plantaris muscles of both groups were harvested after the treatment period, and the expression and phosphorylation levels of metabolic and intracellular signaling proteins were analyzed using Western blotting. We found that HU increased the expression of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the rate-limiting enzyme of the mevalonate pathway, and activated the mTORC1 signaling pathway without activating AKT, an upstream activator of mTORC1. Furthermore, HU increased prenylated Rheb. Collectively, these findings suggest that the activated mevalonate pathway may be involved in the activation of the Rheb/mTORC1 signaling pathway without AKT activation in fast-twitch muscles under prolonged disuse conditions.
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Affiliation(s)
- Munehiro Uda
- School of NursingHirosaki Gakuin UniversityHirosakiAomoriJapan
| | - Toshinori Yoshihara
- Graduate School of Health and Sports ScienceJuntendo UniversityInzaiChibaJapan
| | - Noriko Ichinoseki‐Sekine
- Graduate School of Health and Sports ScienceJuntendo UniversityInzaiChibaJapan
- Faculty of Liberal ArtsThe Open University of JapanChibaJapan
| | - Takeshi Baba
- School of MedicineJuntendo UniversityInzaiChibaJapan
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Jaime D, Fish LA, Madigan LA, Xi C, Piccoli G, Ewing MD, Blaauw B, Fallon JR. The MuSK-BMP pathway maintains myofiber size in slow muscle through regulation of Akt-mTOR signaling. Skelet Muscle 2024; 14:1. [PMID: 38172960 PMCID: PMC10763067 DOI: 10.1186/s13395-023-00329-9] [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: 02/21/2023] [Accepted: 10/19/2023] [Indexed: 01/05/2024] Open
Abstract
Myofiber size regulation is critical in health, disease, and aging. MuSK (muscle-specific kinase) is a BMP (bone morphogenetic protein) co-receptor that promotes and shapes BMP signaling. MuSK is expressed at all neuromuscular junctions and is also present extrasynaptically in the mouse soleus, whose predominantly oxidative fiber composition is akin to that of human muscle. To investigate the role of the MuSK-BMP pathway in vivo, we generated mice lacking the BMP-binding MuSK Ig3 domain. These ∆Ig3-MuSK mice are viable and fertile with innervation levels comparable to wild type. In 3-month-old mice, myofibers are smaller in the slow soleus, but not in the fast tibialis anterior (TA). Transcriptomic analysis revealed soleus-selective decreases in RNA metabolism and protein synthesis pathways as well as dysregulation of IGF1-Akt-mTOR pathway components. Biochemical analysis showed that Akt-mTOR signaling is reduced in soleus but not TA. We propose that the MuSK-BMP pathway acts extrasynaptically to maintain myofiber size in slow muscle by promoting protein synthetic pathways including IGF1-Akt-mTOR signaling. These results reveal a novel mechanism for regulating myofiber size in slow muscle and introduce the MuSK-BMP pathway as a target for promoting muscle growth and combatting atrophy.
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Grants
- R41 AG073144 NIA NIH HHS
- T32 MH020068 NIMH NIH HHS
- U01 NS064295, R41 AG073144, R21 NS112743, R21 AG073743, P30 GM103410, P30 RR031153, P20 RR018728, S10 RR02763, R25GM083270, 2T32AG041688, and T32 MH20068 NIH HHS
- P30 GM103410 NIGMS NIH HHS
- T32 AG041688 NIA NIH HHS
- P30 RR031153 NCRR NIH HHS
- U01 NS064295 NINDS NIH HHS
- R21 NS112743 NINDS NIH HHS
- P20 RR018728 NCRR NIH HHS
- R21 AG073743 NIA NIH HHS
- R25 GM083270 NIGMS NIH HHS
- National Institutes of Health
- Carney Institute for Brain Sciences
- ALS Finding a Cure
- AFM-Téléthon
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Affiliation(s)
- Diego Jaime
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Lauren A Fish
- Department of Neuroscience, Brown University, Providence, RI, 02912, USA
| | - Laura A Madigan
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Chengjie Xi
- Department of Neuroscience, Brown University, Providence, RI, 02912, USA
| | - Giorgia Piccoli
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Madison D Ewing
- Department of Neuroscience, Brown University, Providence, RI, 02912, USA
| | - Bert Blaauw
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Justin R Fallon
- Department of Neuroscience, Brown University, Providence, RI, 02912, USA.
- Carney Institute for Neuroscience, Brown University, Providence, RI, USA.
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4
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Jeong JS, Kim JW, Kim JH, Kim CY, Ko JW, Kim TW. Korean red ginseng suppresses mitochondrial apoptotic pathway in denervation-induced skeletal muscle atrophy. J Ginseng Res 2024; 48:52-58. [PMID: 38223821 PMCID: PMC10785417 DOI: 10.1016/j.jgr.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 06/08/2023] [Accepted: 07/01/2023] [Indexed: 01/16/2024] Open
Abstract
Background Skeletal muscle denervation leads to motor neuron degeneration, which in turn reduces muscle fiber volumes. Recent studies have revealed that apoptosis plays a role in regulating denervation-associated pathologic muscle wasting. Korean red ginseng (KRG) has various biological activities and is currently widely consumed as a medicinal product worldwide. Among them, ginseng has protective effects against muscle atrophy in in vivo and in vitro. However, the effects of KRG on denervation-induced muscle damage have not been fully elucidated. Methods We induced skeletal muscle atrophy in mice by dissecting the sciatic nerves, administered KRG, and then analyzed the muscles. KRG was administered to the mice once daily for 3 weeks at 100 and 400 mg/kg/day doses after operation. Results KRG treatment significantly increased skeletal muscle weight and tibialis anterior (TA) muscle fiber volume in injured areas and reduced histological alterations in TA muscle. In addition, KRG treatment reduced denervation-induced apoptotic changes in TA muscle. KRG attenuated p53/Bax/cytochrome c/Caspase 3 signaling induced by nerve injury in a dose-dependent manner. Also, KRG decreases protein kinase B/mammalian target of rapamycin pathway, reducing restorative myogenesis. Conclusion Thus, KRG has potential protective role against denervation-induced muscle atrophy. The effect of KRG treatment was accompanied by reduced levels of mitochondria-associated apoptosis.
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Affiliation(s)
- Ji-Soo Jeong
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
| | - Jeong-Won Kim
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
| | - Jin-Hwa Kim
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
| | - Chang-Yeop Kim
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
| | - Je-Won Ko
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
| | - Tae-Won Kim
- College of Veterinary Medicine (BK21 FOUR Program), Chungnam National University, Daejeon, Republic of Korea
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Cocchiararo I, Cattaneo O, Rajendran J, Chabry F, Cornut M, Soldati H, Bigot A, Mamchaoui K, Gibertini S, Bouche A, Ham DJ, Laumonier T, Prola A, Castets P. Identification of a muscle-specific isoform of VMA21 as a potent actor in X-linked myopathy with excessive autophagy pathogenesis. Hum Mol Genet 2023; 32:3374-3389. [PMID: 37756622 PMCID: PMC10695681 DOI: 10.1093/hmg/ddad164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/23/2023] [Accepted: 09/21/2023] [Indexed: 09/29/2023] Open
Abstract
Defective lysosomal acidification is responsible for a large range of multi-systemic disorders associated with impaired autophagy. Diseases caused by mutations in the VMA21 gene stand as exceptions, specifically affecting skeletal muscle (X-linked Myopathy with Excessive Autophagy, XMEA) or liver (Congenital Disorder of Glycosylation). VMA21 chaperones vacuolar (v-) ATPase assembly, which is ubiquitously required for proper lysosomal acidification. The reason VMA21 deficiencies affect specific, but divergent tissues remains unknown. Here, we show that VMA21 encodes a yet-unreported long protein isoform, in addition to the previously described short isoform, which we name VMA21-120 and VMA21-101, respectively. In contrast to the ubiquitous pattern of VMA21-101, VMA21-120 was predominantly expressed in skeletal muscle, and rapidly up-regulated upon differentiation of mouse and human muscle precursors. Accordingly, VMA21-120 accumulated during development, regeneration and denervation of mouse skeletal muscle. In contrast, neither induction nor blockade of autophagy, in vitro and in vivo, strongly affected VMA21 isoform expression. Interestingly, VMA21-101 and VMA21-120 both localized to the sarcoplasmic reticulum of muscle cells, and interacted with the v-ATPase. While VMA21 deficiency impairs autophagy, VMA21-101 or VMA21-120 overexpression had limited impact on autophagic flux in muscle cells. Importantly, XMEA-associated mutations lead to both VMA21-101 deficiency and loss of VMA21-120 expression. These results provide important insights into the clinical diversity of VMA21-related diseases and uncover a muscle-specific VMA21 isoform that potently contributes to XMEA pathogenesis.
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Affiliation(s)
- Ilaria Cocchiararo
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Olivia Cattaneo
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Jayasimman Rajendran
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Florent Chabry
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Mélanie Cornut
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Hadrien Soldati
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Anne Bigot
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, 47 Bd de l'Hôpital, 75013 Paris, France
| | - Kamel Mamchaoui
- Centre de Recherche en Myologie, Inserm, Institut de Myologie, Sorbonne Université, 47 Bd de l'Hôpital, 75013 Paris, France
| | - Sara Gibertini
- Neuromuscular Diseases and Neuroimmunology Unit, Muscle Cell Biology Lab, Fondazione IRCCS Istituto Neurologico “C. Besta”, Via Amadeo 42, 20133 Milano, Italy
| | - Axelle Bouche
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
- Department of Orthopaedic Surgery, Geneva University Hospitals and Faculty of Medicine, University Medical Center, 1 rue Michel Servet, 1211, Geneva, Switzerland
| | - Daniel J Ham
- Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Thomas Laumonier
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
- Department of Orthopaedic Surgery, Geneva University Hospitals and Faculty of Medicine, University Medical Center, 1 rue Michel Servet, 1211, Geneva, Switzerland
| | - Alexandre Prola
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
| | - Perrine Castets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, CH-1211 Geneva, Switzerland
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Ishihara H, Otani Y, Tanaka K, Miyajima H, Ngo HX, Fujitani M. Blocking insulin-like growth factor 1 receptor signaling pathway inhibits neuromuscular junction regeneration after botulinum toxin-A treatment. Cell Death Dis 2023; 14:609. [PMID: 37717026 PMCID: PMC10505167 DOI: 10.1038/s41419-023-06128-w] [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: 09/13/2022] [Revised: 08/25/2023] [Accepted: 09/06/2023] [Indexed: 09/18/2023]
Abstract
Botulinum toxin-A (BTX) administration into muscle is an established treatment for conditions with excessive muscle contraction. However, botulinum therapy has short-term effectiveness, and high-dose injection of BTX could induce neutralizing antibodies against BTX. Therefore, prolonging its effects could be beneficial in a clinical situation. Insulin-like growth factor-1 receptor (IGF1R) and its ligands, insulin-like growth factor (IGF) -I and II, regulate the physiological and pathological processes of the nervous system. It has been suggested that IGF1R is involved in the process after BTX administration, but the specific regeneration mechanism remains unclear. Therefore, this study aimed to determine how inhibition of IGF1R signaling pathway affects BTX-induced muscle paralysis. The results showed that anti-IGF1R antibody administration inhibited the recovery from BTX-induced neurogenic paralysis, and the synaptic components at the neuromuscular junction (NMJ), mainly post-synaptic components, were significantly affected by the antibody. In addition, the wet weight or frequency distribution of the cross-sectional area of the muscle fibers was regulated by IGF1R, and sequential antibody administration following BTX treatment increased the number of Pax7+-satellite cells in the gastrocnemius (GC) muscle, independent of NMJ recovery. Moreover, BTX treatment upregulated mammalian target of rapamycin (mTOR)/S6 kinase signaling pathway, HDAC4, Myog, Fbxo32/MAFbx/Atrogin-1 pathway, and transcription of synaptic components, but not autophagy. Finally, IGF1R inhibition affected only mTOR/S6 kinase translational signaling in the GC muscle. In conclusion, the IGF1R signaling pathway is critical for NMJ regeneration via specific translational signals. IGF1R inhibition could be highly beneficial in clinical practice by decreasing the number of injections and total dose of BTX due to the prolonged duration of the effect.
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Affiliation(s)
- Hiroki Ishihara
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
- Department of Rehabilitation, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
| | - Yoshinori Otani
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
| | - Kazuki Tanaka
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
- Department of Rehabilitation, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
| | - Hisao Miyajima
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
| | - Huy Xuan Ngo
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
- Department of Oral and Maxillofacial Surgery, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan
| | - Masashi Fujitani
- Department of Anatomy and Neuroscience, Faculty of Medicine, Shimane University, 89-1 Enya-cho, Izumo-shi, Shimane, 693-8501, Japan.
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7
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Martín AI, Moreno-Rupérez Á, Nebot E, Granado M, Jaque D, Nieto-Bona MP, López-Calderón A, Priego T. Time-Dependent Changes in Muscle IGF1-IGFBP5-PAPP System after Sciatic Denervation. Int J Mol Sci 2023; 24:14112. [PMID: 37762414 PMCID: PMC10531309 DOI: 10.3390/ijms241814112] [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: 07/24/2023] [Revised: 09/08/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Denervation-induced muscle atrophy is a frequent cause of skeletal muscle diseases. However, the role of the most important muscle growth factor, insulin-like growth factor (IGF-1), in this process is poorly understood. IGF-1 activity is controlled by six IGF-1 binding proteins (IGFBPs). In skeletal muscle, IGFBP-5 seems to have an important role in atrophic processes. Furthermore, pappalysins (PAPP-A) modulate muscle growth by increasing IGF-1 bioavailability through IGFBP cleavage. We aimed to study the time-dependent changes in the IGF1-IGFBP5-PAPP system and its regulators in gastrocnemius muscle after sciatic denervation. Gastrocnemius atrophy and overexpression of IGF-1 was observed from day 3 post-denervation. The proteolytic factors measured were elevated from day 1 post-denervation onwards. Expression of both IGFBP-5 and pappalysins were increased on days 1 and 3. Subsequently, on days 7 to 14 pappalysins returned to control levels while IGFBP-5 remained elevated. The ratio IGFBP-5/PAPP-A was correlated with the main proteolytic markers. All data suggest that the initial increase of pappalysins could facilitate the IGF-1 action on muscle growth, whereas their subsequent decrease could lead to further muscle wasting.
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Affiliation(s)
- Ana Isabel Martín
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain; (A.I.M.); (Á.M.-R.); (E.N.); (A.L.-C.)
| | - Álvaro Moreno-Rupérez
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain; (A.I.M.); (Á.M.-R.); (E.N.); (A.L.-C.)
| | - Elena Nebot
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain; (A.I.M.); (Á.M.-R.); (E.N.); (A.L.-C.)
| | - Miriam Granado
- Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Calle Arzobispo Morcillo 2, 28029 Madrid, Spain;
| | - Daniel Jaque
- Nanomaterials for Bioimaging Group (NanoBIG), Departamento de Física de Materiales, Facultad de Ciencias, Universidad Autónoma de Madrid, Avenida Francisco Tomas y Valiente, 28049 Madrid, Spain;
| | - M. Paz Nieto-Bona
- Departamento de Ciencias Básicas de la Salud, Facultad CC Salud, Universidad Rey Juan Carlos, Avenida de Atenas sn, 20922 Madrid, Spain;
| | - Asunción López-Calderón
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain; (A.I.M.); (Á.M.-R.); (E.N.); (A.L.-C.)
| | - Teresa Priego
- Departamento de Fisiología, Facultad de Enfermería, Fisioterapia y Podología, Universidad Complutense de Madrid, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
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Lax A, Soler F, Fernandez del Palacio MJ, Pascual-Oliver S, Ballester MR, Fuster JJ, Pascual-Figal D, Asensio-Lopez MDC. Silencing of microRNA-106b-5p prevents doxorubicin-mediated cardiotoxicity through modulation of the PR55α/YY1/sST2 signaling axis. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 32:704-720. [PMID: 37234747 PMCID: PMC10208836 DOI: 10.1016/j.omtn.2023.04.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 04/28/2023] [Indexed: 05/28/2023]
Abstract
Clinical use of doxorubicin (Dox), an anthracycline with potent anti-tumor effects, is limited because of its highly chemotherapy-induced cardiotoxicity (CIC). After myocardial infarction (MI), we have recently identified Yin Yang-1 (YY1) and histone deacetylase 4 (HDAC4) as two factors involved in the overexpression of the isoform soluble suppression of tumorigenicity 2 (sST2) protein, which acts as a decoy receptor blocking the favorable effects of IL-33. Therefore, high levels of sST2 are associated with increased fibrosis, remodeling, and worse cardiovascular outcomes. No data exist on the role of the YY1/HDAC4/sST2 axis in CIC. This study aimed to evaluate the pathophysiological implication of the molecular YY1/HDAC4/sST2 axis in remodeling that is developed in patients treated with Dox as well as to suggest a novel molecular therapy to prevent anthracycline-induced cardiotoxicity. Here, we have characterized a novel nexus between miR106b-5p (miR-106b) levels and the YY1/HDAC4 axis in relation to the cardiac expression of sST2 using two experimental models with Dox-induced cardiotoxicity. The addition of Dox (5 μM) to human induced pluripotent stem cell-derived cardiomyocytes induced cellular apoptotic death via upregulation of miR-106b-5p (miR-106b), which was confirmed by specific mimic sequences. A functional blockage of miR-106b using the locked nucleic acid antagomir inhibited Dox-induced cardiotoxicity.
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Affiliation(s)
- Antonio Lax
- Biomedical Research Institute Virgen de la Arrixaca (IMIB-Arrixaca), University of Murcia, 30120 Murcia, Spain
| | - Fernando Soler
- Biomedical Research Institute Virgen de la Arrixaca (IMIB-Arrixaca), University of Murcia, 30120 Murcia, Spain
| | | | - Silvia Pascual-Oliver
- Biomedical Research Institute Virgen de la Arrixaca (IMIB-Arrixaca), University of Murcia, 30120 Murcia, Spain
| | - Miriam Ruiz Ballester
- Biomedical Research Institute Virgen de la Arrixaca (IMIB-Arrixaca), University of Murcia, 30120 Murcia, Spain
| | - Jose Javier Fuster
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain
| | - Domingo Pascual-Figal
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), 28029 Madrid, Spain
- Cardiology Department, Hospital Virgen de la Arrixaca, IMIB-Arrixaca and University of Murcia, 30120 Murcia, Spain
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain
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9
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Uemichi K, Shirai T, Takemasa T. Combined effects of functional overload and denervation on skeletal muscle mass and its regulatory proteins in mice. Physiol Rep 2023; 11:e15689. [PMID: 37161590 PMCID: PMC10169777 DOI: 10.14814/phy2.15689] [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: 03/21/2023] [Revised: 03/29/2023] [Accepted: 03/31/2023] [Indexed: 05/11/2023] Open
Abstract
Skeletal muscle is a highly pliable tissue and various adaptations such as muscle hypertrophy or atrophy are induced by overloading or disuse, respectively. However, the combined effect of overloading and disuse on the quantitative adaptation of skeletal muscle is unknown. Thus, the aim of this study was to investigate the effects of the combined stimuli of overloading and disuse on mouse skeletal muscle mass and the expression of regulatory factors for muscle protein anabolism or catabolism. Male mice from the Institute Cancer Research were subjected to denervation concomitant with unilateral functional overload or functional overload concomitant with unilateral denervation. Disuse and functional overload were induced by sciatic nerve transection (denervation) and synergist ablation, respectively, and the plantaris muscle was harvested 14 days after the operation. Our results showed that denervation attenuated functional overload-induced muscle hypertrophy and functional overload partially ameliorated the denervation-induced muscle atrophy. P70S6K phosphorylation, an indicator of mechanistic target of rapamycin complex 1 (mTORC1) activation, was not increased by unilateral functional overload in denervated muscles or by unilateral denervation in functional overloaded muscles. Denervation did not affect the increase of LC3-II, a marker of autophagy activation, and ubiquitinated protein expression upon unilateral functional overload. Also, functional overload did not affect ubiquitinated protein expression during unilateral denervation. Thus, our findings suggest that functional overload-induced muscle hypertrophy or denervation-induced muscle atrophy was attenuated by the combined stimuli of overload and denervation.
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Affiliation(s)
- Kazuki Uemichi
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan
| | - Takanaga Shirai
- Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan
| | - Tohru Takemasa
- Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan
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10
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Lv X, Tang W, Qin J, Wang W, Dong J, Wei Y. The crosslinks between ferroptosis and autophagy in asthma. Front Immunol 2023; 14:1140791. [PMID: 37063888 PMCID: PMC10090423 DOI: 10.3389/fimmu.2023.1140791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/17/2023] [Indexed: 03/31/2023] Open
Abstract
Autophagy is an evolutionarily conserved cellular process capable of degrading various biological molecules and organelles via the lysosomal pathway. Ferroptosis is a type of oxidative stress-dependent regulated cell death associated with the iron accumulation and lipid peroxidation. The crosslinks between ferroptosis and autophagy have been focused on since the dependence of ferroptosis on autophagy was discovered. Although the research and theories on the relationship between autophagy and ferroptosis remain scattered and fragmented, the crosslinks between these two forms of regulated cell death are closely related to the treatment of various diseases. Thereof, asthma as a chronic inflammatory disease has a tight connection with the occurrence of ferroptosis and autophagy since the crosslinked signal pathways may be the crucial regulators or exactly regulated by cells and secretion in the immune system. In addition, non-immune cells associated with asthma are also closely related to autophagy and ferroptosis. Further studies of cross-linking asthma inflammation with crosslinked signaling pathways may provide us with several key molecules that regulate asthma through specific regulators. The crosslinks between autophagy and ferroptosis provide us with a new perspective to interpret and understand the manifestations of asthma, potential drug discovery targets, and new therapeutic options to effectively intervene in the imbalance caused by abnormal inflammation in asthma. Herein, we introduce the main molecular mechanisms of ferroptosis, autophagy, and asthma, describe the role of crosslinks between ferroptosis and autophagy in asthma based on their common regulatory cells or molecules, and discuss potential drug discovery targets and therapeutic applications in the context of immunomodulatory and symptom alleviation.
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Affiliation(s)
- Xiaodi Lv
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Weifeng Tang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Jingjing Qin
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Wenqian Wang
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Jingcheng Dong
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
- *Correspondence: Ying Wei, ; Jingcheng Dong,
| | - Ying Wei
- Department of Integrative Medicine, Huashan Hospital, Fudan University, Shanghai, China
- Institutes of Integrative Medicine, Fudan University, Shanghai, China
- *Correspondence: Ying Wei, ; Jingcheng Dong,
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11
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Uemichi K, Shirai T, Matsuno R, Iwata T, Tanimura R, Takemasa T. The role of the mechanistic target of rapamycin complex 1 in the regulation of mitochondrial adaptation during skeletal muscle atrophy under denervation or calorie restriction in mice. Appl Physiol Nutr Metab 2023; 48:241-255. [PMID: 36786420 DOI: 10.1139/apnm-2022-0336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Mechanistic target of rapamycin complex 1 (mTORC1) is a protein complex that regulates skeletal muscle protein synthesis and hypertrophy. mTORC1-mediated signaling activities are activated during denervation-induced skeletal muscle atrophy and suppressed during calorie restriction-induced atrophy. Mitochondria control the qualitative plasticity of skeletal muscles primarily through biogenesis, fusion, and fission. We recently showed that mTORC1 activation contributes toward mitochondrial homeostasis. In this study, we examined the role of mTORC1 in mitochondrial adaptation during denervation- or calorie restriction-induced skeletal muscle atrophy. Seven-week-old Institute of Cancer Research mice were subjected to 14 days of denervation or calorie restriction combined with the administration of the mTORC1 inhibitor-"rapamycin". Our results showed that although mTORC1 inhibition did not alter mitochondrial biogenesis, content and enzyme activity, it suppressed the activation of dynamin-related protein 1 (DRP1), a mitochondrial fission-related protein in denervated muscle, and reduced DRP1 expression in calorie-restricted muscle. Furthermore, calorie restriction-induced mitochondrial fragmentation was partially suppressed by mTORC1 inhibition. Taken together, our results indicate that mTORC1 activation upon denervation and inhibition upon calorie restriction contributes to qualitative changes in muscle plasticity by at least partially regulating the mitochondrial fission response.
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Affiliation(s)
- Kazuki Uemichi
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Takanaga Shirai
- Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan.,Faculty of Health and Sports Sciences, University of Tsukuba, Tsukuba, Japan
| | - Ryunosuke Matsuno
- School of Physical Education, Health and Sports Sciences, University of Tsukuba, Tsukuba, Japan.,Terumo Corporation, Tokyo, Japan
| | - Tomohiro Iwata
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Riku Tanimura
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Tohru Takemasa
- Faculty of Health and Sports Sciences, University of Tsukuba, Tsukuba, Japan
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12
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Jaime D, Fish LA, Madigan LA, Ewing MD, Fallon JR. The MuSK-BMP pathway maintains myofiber size in slow muscle through regulation of Akt- mTOR signaling. RESEARCH SQUARE 2023:rs.3.rs-2613527. [PMID: 36909467 PMCID: PMC10002845 DOI: 10.21203/rs.3.rs-2613527/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Myofiber size regulation is critical in health, disease, and aging. MuSK (muscle-specific kinase) is a BMP (bone morphogenetic protein) co-receptor that promotes and shapes BMP signaling. MuSK is expressed at all neuromuscular junctions and is also present extrasynaptically in the slow soleus muscle. To investigate the role of the MuSK-BMP pathway in vivo we generated mice lacking the BMP-binding MuSK Ig3 domain. These ΔIg3-MuSKmice are viable and fertile with innervation levels comparable to wild type. In 3-month-old mice myofibers are smaller in the slow soleus, but not in the fast tibialis anterior (TA). Transcriptomic analysis revealed soleus-selective decreases in RNA metabolism and protein synthesis pathways as well as dysregulation of IGF1-Akt-mTOR pathway components. Biochemical analysis showed that Akt-mTOR signaling is reduced in soleus but not TA. We propose that the MuSK-BMP pathway acts extrasynaptically to maintain myofiber size in slow muscle by promoting protein synthetic pathways including IGF1-Akt-mTOR signaling. These results reveal a novel mechanism for regulating myofiber size in slow muscle and introduce the MuSK-BMP pathway as a target for promoting muscle growth and combatting atrophy.
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13
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Muscle 4EBP1 activation modifies the structure and function of the neuromuscular junction in mice. Nat Commun 2022; 13:7792. [PMID: 36526657 PMCID: PMC9758177 DOI: 10.1038/s41467-022-35547-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022] Open
Abstract
Dysregulation of mTOR complex 1 (mTORC1) activity drives neuromuscular junction (NMJ) structural instability during aging; however, downstream targets mediating this effect have not been elucidated. Here, we investigate the roles of two mTORC1 phosphorylation targets for mRNA translation, ribosome protein S6 kinase 1 (S6K1) and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1), in regulating NMJ structural instability induced by aging and sustained mTORC1 activation. While myofiber-specific deletion of S6k1 has no effect on NMJ structural integrity, 4EBP1 activation in murine muscle induces drastic morphological remodeling of the NMJ with enhancement of synaptic transmission. Mechanistically, structural modification of the NMJ is attributed to increased satellite cell activation and enhanced post-synaptic acetylcholine receptor (AChR) turnover upon 4EBP1 activation. Considering that loss of post-synaptic myonuclei and reduced NMJ turnover are features of aging, targeting 4EBP1 activation could induce NMJ renewal by expanding the pool of post-synaptic myonuclei as an alternative intervention to mitigate sarcopenia.
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14
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Wu SH, Lu IC, Yang SM, Hsieh CF, Chai CY, Tai MH, Huang SH. Spinal Irisin Gene Delivery Attenuates Burn Injury-Induced Muscle Atrophy by Promoting Axonal Myelination and Innervation of Neuromuscular Junctions. Int J Mol Sci 2022; 23:ijms232415899. [PMID: 36555538 PMCID: PMC9784798 DOI: 10.3390/ijms232415899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 12/10/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022] Open
Abstract
Muscle loss and weakness after a burn injury are typically the consequences of neuronal dysregulation and metabolic change. Hypermetabolism has been noted to cause muscle atrophy. However, the mechanism underlying the development of burn-induced motor neuropathy and its contribution to muscle atrophy warrant elucidation. Current therapeutic interventions for burn-induced motor neuropathy demonstrate moderate efficacy and have side effects, which limit their usage. We previously used a third-degree burn injury rodent model and found that irisin-an exercise-induced myokine-exerts a protective effect against burn injury-induced sensory and motor neuropathy by attenuating neuronal damage in the spinal cord. In the current study, spinal irisin gene delivery was noted to attenuate burn injury-induced sciatic nerve demyelination and reduction of neuromuscular junction innervation. Spinal overexpression of irisin leads to myelination rehabilitation and muscular innervation through the modulation of brain-derived neurotrophic factor and glial-cell-line-derived neurotrophic factor expression along the sciatic nerve to the muscle tissues and thereby modulates the Akt/mTOR pathway and metabolic derangement and prevents muscle atrophy.
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Affiliation(s)
- Sheng-Hua Wu
- Department of Anesthesiology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung 801, Taiwan
- Department of Anesthesiology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
| | - I-Cheng Lu
- Department of Anesthesiology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
- Department of Anesthesiology, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 812, Taiwan
| | - Shih-Ming Yang
- Institute of Biomedical Sciences, National Sun Yat-Sun University, Kaohsiung 804, Taiwan
| | - Chia-Fang Hsieh
- Department of Anesthesiology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung 801, Taiwan
| | - Chee-Yin Chai
- Institute of Biomedical Sciences, National Sun Yat-Sun University, Kaohsiung 804, Taiwan
- Department of Pathology, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
| | - Ming-Hong Tai
- Institute of Biomedical Sciences, National Sun Yat-Sun University, Kaohsiung 804, Taiwan
- Correspondence: (M.-H.T.); (S.-H.H.)
| | - Shu-Hung Huang
- Department of Surgery, Division of Plastic Surgery, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
- Department of Surgery, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Regeneration Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Surgery, Division of Plastic Surgery, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 812, Taiwan
- Correspondence: (M.-H.T.); (S.-H.H.)
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15
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Abstract
Skeletal muscle mass is a very plastic characteristic of skeletal muscle and is regulated by signaling pathways that control the balance between anabolic and catabolic processes. The serine/threonine kinase mechanistic/mammalian target of rapamycin (mTOR) has been shown to be critically important in the regulation of skeletal muscle mass through its regulation of protein synthesis and degradation pathways. In this commentary, recent advances in the understanding of the role of mTORC1 in the regulation of muscle mass under conditions that induce hypertrophy and atrophy will be highlighted.
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Affiliation(s)
- Sue C Bodine
- Department of Internal Medicine, Division of Endocrinology and Metabolism, University of Iowa Carver College of Medicine, 200 Hawkins Drive, Iowa City, IA 52242, USA
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16
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Kaiser MS, Milan G, Ham DJ, Lin S, Oliveri F, Chojnowska K, Tintignac LA, Mittal N, Zimmerli CE, Glass DJ, Zavolan M, Rüegg MA. Dual roles of mTORC1-dependent activation of the ubiquitin-proteasome system in muscle proteostasis. Commun Biol 2022; 5:1141. [PMID: 36302954 PMCID: PMC9613904 DOI: 10.1038/s42003-022-04097-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 10/11/2022] [Indexed: 12/02/2022] Open
Abstract
Muscle size is controlled by the PI3K-PKB/Akt-mTORC1-FoxO pathway, which integrates signals from growth factors, energy and amino acids to activate protein synthesis and inhibit protein breakdown. While mTORC1 activity is necessary for PKB/Akt-induced muscle hypertrophy, its constant activation alone induces muscle atrophy. Here we show that this paradox is based on mTORC1 activity promoting protein breakdown through the ubiquitin-proteasome system (UPS) by simultaneously inducing ubiquitin E3 ligase expression via feedback inhibition of PKB/Akt and proteasome biogenesis via Nuclear Factor Erythroid 2-Like 1 (Nrf1). Muscle growth was restored by reactivation of PKB/Akt, but not by Nrf1 knockdown, implicating ubiquitination as the limiting step. However, both PKB/Akt activation and proteasome depletion by Nrf1 knockdown led to an immediate disruption of proteome integrity with rapid accumulation of damaged material. These data highlight the physiological importance of mTORC1-mediated PKB/Akt inhibition and point to juxtaposed roles of the UPS in atrophy and proteome integrity. Exploring the relationship between mTORC1 and the ubiquitin-proteasome system, light is shed on the paradox between mTORC1-mediated muscle hypertrophy induced by PKB/Akt and the muscle atrophy induced by mTORC1 alone.
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Affiliation(s)
- Marco S Kaiser
- Biozentrum, University of Basel, Basel, Switzerland.,BIOREBA AG, Christoph Merian-Ring 7, 4153, Reinach, Switzerland
| | - Giulia Milan
- Biozentrum, University of Basel, Basel, Switzerland. .,Department of Biomedicine, University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland.
| | - Daniel J Ham
- Biozentrum, University of Basel, Basel, Switzerland.
| | - Shuo Lin
- Biozentrum, University of Basel, Basel, Switzerland
| | | | - Kathrin Chojnowska
- Biozentrum, University of Basel, Basel, Switzerland.,AstraZeneca AG, Neuhofstrasse 34, 6340, Baar, Switzerland
| | - Lionel A Tintignac
- Biozentrum, University of Basel, Basel, Switzerland.,Neuromuscular Research Group, Departments of Neurology and Biomedicine, University of Basel, University Hospital Basel, Basel, Switzerland
| | | | - Christian E Zimmerli
- Biozentrum, University of Basel, Basel, Switzerland.,Department of Molecular Sociology, Max Planck Institute of Biophysics, Max-von-Laue-Straße 3, 60438, Frankfurt am Main, Germany
| | - David J Glass
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA.,Regeneron Pharmaceuticals, Tarrytown, NY, USA
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17
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Bai L, Tu WY, Xiao Y, Zhang K, Shen C. Motoneurons innervation determines the distinct gene expressions in multinucleated myofibers. Cell Biosci 2022; 12:140. [PMID: 36042463 PMCID: PMC9429338 DOI: 10.1186/s13578-022-00876-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 08/09/2022] [Indexed: 11/22/2022] Open
Abstract
Background Neuromuscular junctions (NMJs) are peripheral synapses connecting motoneurons and skeletal myofibers. At the postsynaptic side in myofibers, acetylcholine receptor (AChR) proteins are clustered by the neuronal agrin signal. Meanwhile, several nuclei in each myofiber are specially enriched around the NMJ for postsynaptic gene transcription. It remains mysterious that how gene expressions in these synaptic nuclei are systematically regulated, especially by motoneurons. Results We found that synaptic nuclei have a distinctive chromatin structure and gene expression profiling. Synaptic nuclei are formed during NMJ development and maintained by motoneuron innervation. Transcriptome analysis revealed that motoneuron innervation determines the distinct expression patterns in the synaptic region and non-synaptic region in each multinucleated myofiber, probably through epigenetic regulation. Myonuclei in synaptic and non-synaptic regions have different responses to denervation. Weighted gene co-expression network analysis revealed that the histone lysine demethylases Kdm1a is a negative regulator of synaptic gene expression. Inhibition of Kdm1a promotes AChR expression but impairs motor functions. Conclusion These results demonstrate that motoneurons innervation determines the distinct gene expressions in multinucleated myofibers. Thus, dysregulation of nerve-controlled chromatin structure and muscle gene expression might cause muscle weakness and atrophy in motoneuron degenerative disorders. Supplementary Information The online version contains supplementary material available at 10.1186/s13578-022-00876-6.
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18
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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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19
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Tinline-Goodfellow CT, Fung HJW, Estafanos S, Bailleul C, Lees MJ. Is denervation-induced TFEB translocation hitting an mTOR nerve? J Physiol 2022; 600:3403-3404. [PMID: 35781286 DOI: 10.1113/jp283409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
| | - Hugo J W Fung
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Stephanie Estafanos
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Celine Bailleul
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Matthew J Lees
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
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20
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Roy A, Kumar A. Supraphysiological activation of TAK1 promotes skeletal muscle growth and mitigates neurogenic atrophy. Nat Commun 2022; 13:2201. [PMID: 35459245 PMCID: PMC9033787 DOI: 10.1038/s41467-022-29752-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 03/30/2022] [Indexed: 12/25/2022] Open
Abstract
Skeletal muscle mass is regulated through coordinated activation of multiple signaling pathways. TAK1 signalosome has been found to be activated in various conditions of muscle atrophy and hypertrophy. However, the role and mechanisms by which TAK1 regulates skeletal muscle mass remain less understood. Here, we demonstrate that supraphysiological activation of TAK1 in skeletal muscle of adult mice stimulates translational machinery, protein synthesis, and myofiber growth. TAK1 causes phosphorylation of elongation initiation factor 4E (eIF4E) independent of mTOR. Inactivation of TAK1 disrupts neuromuscular junction morphology and causes deregulation of Smad signaling. Using genetic approaches, we demonstrate that TAK1 prevents excessive loss of muscle mass during denervation. TAK1 favors the nuclear translocation of Smad4 and cytoplasmic retention of Smad6. TAK1 is also required for the phosphorylation of eIF4E in denervated skeletal muscle. Collectively, our results demonstrate that TAK1 supports skeletal muscle growth and prevents neurogenic muscle atrophy in adult mice. TGF-β-activated kinase 1 (TAK1) is essential for the maintenance of skeletal muscle mass through incompletely understood mechanisms. Here the authors show that supraphysiological activation of TAK1 leads to muscle hypertrophy through the elongation initiation factor 4E (eIF4E) involved in protein synthesis, and prevents denervation-induced atrophy in mice.
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Affiliation(s)
- Anirban Roy
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX, USA
| | - Ashok Kumar
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX, USA.
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21
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Jones EJ, Chiou S, Atherton PJ, Phillips BE, Piasecki M. Ageing and exercise-induced motor unit remodelling. J Physiol 2022; 600:1839-1849. [PMID: 35278221 PMCID: PMC9314090 DOI: 10.1113/jp281726] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 02/14/2022] [Indexed: 11/08/2022] Open
Abstract
A motor unit (MU) comprises the neuron cell body, its corresponding axon and each of the muscle fibres it innervates. Many studies highlight age-related reductions in the number of MUs, yet the ability of a MU to undergo remodelling and to expand to rescue denervated muscle fibres is also a defining feature of MU plasticity. Remodelling of MUs involves two coordinated processes: (i) axonal sprouting and new branching growth from adjacent surviving neurons, and (ii) the formation of key structures around the neuromuscular junction to resume muscle-nerve communication. These processes rely on neurotrophins and coordinated signalling in muscle-nerve interactions. To date, several neurotrophins have attracted focus in animal models, including brain-derived neurotrophic factor and insulin-like growth factors I and II. Exercise in older age has demonstrated benefits in multiple physiological systems including skeletal muscle, yet evidence suggests this may also extend to peripheral MU remodelling. There is, however, a lack of research in humans due to methodological limitations which are easily surmountable in animal models. To improve mechanistic insight of the effects of exercise on MU remodelling with advancing age, future research should focus on combining methodological approaches to explore the in vivo physiological function of the MU alongside alterations of the localised molecular environment.
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Affiliation(s)
- Eleanor J. Jones
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Shin‐Yi Chiou
- School of SportExercise, and Rehabilitation Sciences, MRC‐Versus Arthritis Centre for Musculoskeletal Ageing Research, Centre for Human Brain HealthUniversity of BirminghamBirminghamUK
| | - Philip J. Atherton
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Bethan E. Phillips
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Mathew Piasecki
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
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22
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Fan H, He J, Bai Y, He Q, Zhang T, Zhang J, Yang G, Xu Z, Hu J, Yao G. Baicalin improves the functions of granulosa cells and the ovary in aged mice through the mTOR signaling pathway. J Ovarian Res 2022; 15:34. [PMID: 35300716 PMCID: PMC8932175 DOI: 10.1186/s13048-022-00965-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Accepted: 02/28/2022] [Indexed: 12/18/2022] Open
Abstract
Background The mammalian follicle is the basic functional unit of the ovary, and its normal development is required to obtaining oocytes capable of fertilization. As women get older or decline in ovarian function due to certain pathological factors, the growth and development of follicles becomes abnormal, which ultimately leads to infertility and other related female diseases. Kuntai capsules are currently used in clinical practice to improve ovarian function, and they contain the natural compound Baicalin, which is a natural compound with important biological activities. At present, the role and mechanism of Baicalin in the development of ovarian follicles is unclear. Methods Human primary granulosa cells collected from follicular fluid, and then cultured and treated with Baicalin or its normal control, assessed for viability, subjected to RT-PCR, western blotting, flow cytometry, and hormone analyses. The estrus cycle and oocytes of CD-1 mice were studied after Baicalin administration and compared with controls. Ovaries were collected from the mice and subjected to hematoxylin-eosin staining and immunohistochemistry analysis. Results We showed that Baicalin had a dose-dependent effect on granulosa cells cultured in vitro. A low concentration of Baicalin (for example, 10 μM) helped to maintain the viability of granulosa cells; however, at a concentration exceeding 50 μM, it exerted a toxic effect. A low concentration significantly improved the viability of granulosa cells and inhibited cell apoptosis, which may be related to the resultant upregulation of Bcl-2 expression and downregulation of Bax and Caspase 3. By constructing a hydrogen peroxide-induced cell oxidative stress damage model, we found that Baicalin reversed the cell damage caused by hydrogen peroxide. In addition, Baicalin increased the secretion of estradiol and progesterone by upregulating P450arom and stAR. The results of the in vivo experiment showed that the intragastric administration of Baicalin to aged mice improved the estrous cycle and oocyte quality. Furthermore, we observed that Baicalin enhanced the viability of granulosa cells through the mTOR pathway, which in turn improve ovarian function. Conclusion These results indicate that Baicalin could improve the viability of ovarian granulosa cells and the secretion of steroid hormones and thus could help to improve degenerating ovarian function and delay ovarian aging. Supplementary Information The online version contains supplementary material available at 10.1186/s13048-022-00965-7.
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Affiliation(s)
- Huiying Fan
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Jiahuan He
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yucheng Bai
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Qina He
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Tongwei Zhang
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Junya Zhang
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Guang Yang
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Ziwen Xu
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Jingyi Hu
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Guidong Yao
- Center for Reproductive Medicine, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China. .,Henan Key Laboratory of Reproduction and Genetics, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
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23
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Cicatiello AG, Sagliocchi S, Nappi A, Di Cicco E, Miro C, Murolo M, Stornaiuolo M, Dentice M. Thyroid hormone regulates glutamine metabolism and anaplerotic fluxes by inducing mitochondrial glutamate aminotransferase GPT2. Cell Rep 2022; 38:110409. [PMID: 35196498 PMCID: PMC8889437 DOI: 10.1016/j.celrep.2022.110409] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/29/2021] [Accepted: 01/27/2022] [Indexed: 12/27/2022] Open
Abstract
Thyroid hormones (THs) are key metabolic regulators coordinating short- and long-term energy needs. In skeletal muscle, THs modulate energy metabolism in pathophysiological conditions. Indeed, hypo- and hyperthyroidism are leading causes of muscle weakness and strength; however, the metabolic pathways underlying these effects are still poorly understood. Using molecular, biochemical, and isotope-tracing approaches combined with mass spectrometry and denervation experiments, we find that THs regulate glutamine metabolism and anaplerotic fluxes by up-regulating the glutamate pyruvate transaminase 2 (GPT2) gene. In humans, GPT2 autosomal recessive mutations cause a neurological syndrome characterized by intellectual disability, microcephaly, and progressive motor symptoms. Here, we demonstrate a role of the TH/GPT2 axis in skeletal muscle in which it regulates muscle weight and fiber diameter in resting and atrophic conditions and results in protection from muscle loss during atrophy. These results describe an anabolic route by which THs rewire glutamine metabolism toward the maintenance of muscle mass. THs induce the expression of the mitochondrial GPT2 gene in skeletal muscle The GPT2 up-regulation by THs enhances anaplerotic cycles and α-KG production GPT2 is reduced during muscle atrophy and is reactivated by THs treatment GPT2 KO+/– mice undergo muscle loss that is partially attenuated by THs
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Affiliation(s)
| | - Serena Sagliocchi
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Annarita Nappi
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Emery Di Cicco
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Caterina Miro
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Melania Murolo
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Mariano Stornaiuolo
- Department of Pharmacy, University of Naples "Federico II", Naples, NA 80138 Italy
| | - Monica Dentice
- Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, NA 80138 Italy; CEINGE-Biotecnologie Avanzate Scarl, Naples, NA 80131, Italy.
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24
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Geremia A, Sartori R, Baraldo M, Nogara L, Balmaceda V, Dumitras GA, Ciciliot S, Scalabrin M, Nolte H, Blaauw B. Activation of Akt-mTORC1 signalling reverts cancer-dependent muscle wasting. J Cachexia Sarcopenia Muscle 2022; 13:648-661. [PMID: 34741441 PMCID: PMC8818597 DOI: 10.1002/jcsm.12854] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 10/04/2021] [Accepted: 10/07/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Cancer-related muscle wasting occurs in most cancer patients. An important regulator of adult muscle mass and function is the Akt-mTORC1 pathway. While Akt-mTORC1 signalling is important for adult muscle homeostasis, it is also a major target of numerous cancer treatments. Which role Akt-mTORC1 signalling plays during cancer cachexia in muscle is currently not known. Here, we aimed to determine how activation or inactivation of the pathway affects skeletal muscle during cancer cachexia. METHODS We used inducible, muscle-specific Raptor ko (mTORC1) mice to determine the effect of reduced mTOR signalling during cancer cachexia. On the contrary, in order to understand if skeletal muscles maintain their anabolic capacity and if activation of Akt-mTORC1 signalling can reverse cancer cachexia, we generated mice in which we can inducibly activate Akt specifically in skeletal muscles. RESULTS We found that mTORC1 signalling is impaired during cancer cachexia, using the Lewis lung carcinoma and C26 colon cancer model, and is accompanied by a reduction in protein synthesis rates of 57% (P < 0.01). Further reduction of mTOR signalling, as seen in Raptor ko animals, leads to a 1.5-fold increase in autophagic flux (P > 0.001), but does not further increase muscle wasting. On the other hand, activation of Akt-mTORC1 signalling in already cachectic animals completely reverses the 15-20% loss in muscle mass and force (P < 0.001). Interestingly, Akt activation only in skeletal muscle completely normalizes the transcriptional deregulation observed in cachectic muscle, despite having no effect on tumour size or spleen mass. In addition to stimulating muscle growth, it is also sufficient to prevent the increase in protein degradation normally observed in muscles from tumour-bearing animals. CONCLUSIONS Here, we show that activation of Akt-mTORC1 signalling is sufficient to completely revert cancer-dependent muscle wasting. Intriguingly, these results show that skeletal muscle maintains its anabolic capacities also during cancer cachexia, possibly giving a rationale behind some of the beneficial effects observed in exercise in cancer patients.
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Affiliation(s)
- Alessia Geremia
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
| | | | - Martina Baraldo
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Leonardo Nogara
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
| | | | - Georgia Ana Dumitras
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
| | | | - Marco Scalabrin
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Hendrik Nolte
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Bert Blaauw
- Veneto Institute of Molecular Medicine (VIMM), Padua, Italy.,Department of Biomedical Sciences, University of Padua, Padua, Italy
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25
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Mechanism of Gegen Qinlian Decoction Regulating ABTB1 Expression in Colorectal Cancer Metastasis Based on PI3K/AKT/FOXO1 Pathway. BIOMED RESEARCH INTERNATIONAL 2022; 2022:8131531. [PMID: 35111848 PMCID: PMC8803423 DOI: 10.1155/2022/8131531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/03/2021] [Accepted: 12/14/2021] [Indexed: 12/25/2022]
Abstract
It was to investigate the role of Gegen Qinlian decoction (GQD) in the regulation of ABTB1 gene based on PI3K/AKT/FOXO1 signaling pathway in colorectal cancer (CRC) metastasis. In this study, 10 cases of the CRC mouse model were established by inoculating CT26 cells into the spleen of mice, which were divided into the experimental group and the control group, 5 cases in each group; the control group was intragastrically administered with normal saline 0.3 mL/d, and the experimental group was intragastrically administered with GQD 0.2 mL/d at a ratio of 0.2 g medicinal materials/10 g for 10 days and sacrificed, and pathological sections were made. The expression density of signaling pathway PI3K/AKT/FOXO1 as well as gene ABTB1 was detected in the sections of the two groups, and the mechanism of action of this gene in the two groups of mice was studied. It was found that the densities of p-PI3K, p-AKT, and p-FOXO1 in the experimental group of mice were 26.55 g/cm3, 70.2 g/cm3, and 24.36 g/cm3, respectively, which were significantly increased compared with the control group, P < 0.05; the density of ABTB1 was 35.4 g/cm3, which was significantly increased compared with the control group, P < 0.05; the proliferation and migration ability of CRC cells in the experimental group were significantly decreased, P < 0.05. GQD can promote the expression of ABTB1 by activating the PI3K/AKT/FOXO1 signaling pathway, in order to inhibit the proliferation and growth ability of CRC cells.
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26
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Emmert ME, Aggarwal P, Shay-Winkler K, Lee SJ, Goh Q, Cornwall R. Sex-specific role of myostatin signaling in neonatal muscle growth, denervation atrophy, and neuromuscular contractures. eLife 2022; 11:81121. [PMID: 36314781 PMCID: PMC9873256 DOI: 10.7554/elife.81121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 10/31/2022] [Indexed: 01/27/2023] Open
Abstract
Neonatal brachial plexus injury (NBPI) causes disabling and incurable muscle contractures that result from impaired longitudinal growth of denervated muscles. This deficit in muscle growth is driven by increased proteasome-mediated protein degradation, suggesting a dysregulation of muscle proteostasis. The myostatin (MSTN) pathway, a prominent muscle-specific regulator of proteostasis, is a putative signaling mechanism by which neonatal denervation could impair longitudinal muscle growth, and thus a potential target to prevent NBPI-induced contractures. Through a mouse model of NBPI, our present study revealed that pharmacologic inhibition of MSTN signaling induces hypertrophy, restores longitudinal growth, and prevents contractures in denervated muscles of female but not male mice, despite inducing hypertrophy of normally innervated muscles in both sexes. Additionally, the MSTN-dependent impairment of longitudinal muscle growth after NBPI in female mice is associated with perturbation of 20S proteasome activity, but not through alterations in canonical MSTN signaling pathways. These findings reveal a sex dimorphism in the regulation of neonatal longitudinal muscle growth and contractures, thereby providing insights into contracture pathophysiology, identifying a potential muscle-specific therapeutic target for contracture prevention, and underscoring the importance of sex as a biological variable in the pathophysiology of neuromuscular disorders.
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Affiliation(s)
- Marianne E Emmert
- Department of Medical Sciences, University of Cincinnati College of MedicineCincinnatiUnited States
| | - Parul Aggarwal
- Division of Orthopaedic Surgery, Cincinnati Children’s Hospital Medical CenterCincinnatiUnited States
| | - Kritton Shay-Winkler
- Division of Orthopaedic Surgery, Cincinnati Children’s Hospital Medical CenterCincinnatiUnited States
| | - Se-Jin Lee
- The Jackson LaboratoryFarmingtonUnited States,Department of Genetics and Genome Sciences, University of Connecticut School of MedicineFarmingtonUnited States
| | - Qingnian Goh
- Division of Orthopaedic Surgery, Cincinnati Children’s Hospital Medical CenterCincinnatiUnited States,Department of Orthopaedic Surgery, University of Cincinnati College of MedicineCincinnatiUnited States
| | - Roger Cornwall
- Division of Orthopaedic Surgery, Cincinnati Children’s Hospital Medical CenterCincinnatiUnited States,Department of Orthopaedic Surgery, University of Cincinnati College of MedicineCincinnatiUnited States,Division of Developmental Biology, Cincinnati Children’s Hospital Medical CenterCincinnatiUnited States,Department of Pediatrics, University of Cincinnati College of MedicineCincinnatiUnited States
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27
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You JS, Chen J. Aging Does Not Exacerbate Muscle Loss During Denervation and Lends Unique Muscle-Specific Atrophy Resistance With Akt Activation. Front Physiol 2021; 12:779547. [PMID: 34916960 PMCID: PMC8669767 DOI: 10.3389/fphys.2021.779547] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 11/09/2021] [Indexed: 01/10/2023] Open
Abstract
Sarcopenia, or age-related skeletal muscle atrophy and weakness, imposes significant clinical and economic burdens on affected patients and societies. Neurological degeneration, such as motoneuron death, has been recognized as a key contributor to sarcopenia. However, little is known about how aged/sarcopenic muscle adapts to this denervation stress. Here, we show that mice at 27months of age exhibit clear signs of sarcopenia but no accelerated denervation-induced muscle atrophy when compared to 8-month-old mice. Surprisingly, aging lends unique atrophy resistance to tibialis anteria muscle, accompanied by an increase in the cascade of mammalian target of rapamycin complex 1 (mTORC1)-independent anabolic events involving Akt signaling, rRNA biogenesis, and protein synthesis during denervation. These results expand our understanding of age-dependent stress responses and may help develop better countermeasures to sarcopenia.
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Affiliation(s)
- Jae-Sung You
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Jie Chen
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
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28
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Albadrani H, Ammar T, Bader M, Renaud JM. Angiotensin 1-7 prevents the excessive force loss resulting from 14- and 28-day denervation in mouse EDL and soleus muscle. J Gen Physiol 2021; 153:212748. [PMID: 34739541 PMCID: PMC8576869 DOI: 10.1085/jgp.201912556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 06/30/2021] [Accepted: 08/11/2021] [Indexed: 11/20/2022] Open
Abstract
Denervation leads to muscle atrophy, which is described as muscle mass and force loss, the latter exceeding expectation from mass loss. The objective of this study was to determine the efficiency of angiotensin (Ang) 1–7 at reducing muscle atrophy in mouse extensor digitorum longus (EDL) and soleus following 14- and 28-d denervation periods. Some denervated mice were treated with Ang 1–7 or diminazene aceturate (DIZE), an ACE2 activator, to increase Ang 1–7 levels. Ang 1–7/DIZE treatment had little effect on muscle mass loss and fiber cross-sectional area reduction. Ang 1–7 and DIZE fully prevented the loss of tetanic force normalized to cross-sectional area and accentuated the increase in twitch force in denervated muscle. However, they did not prevent the shift of the force–frequency relationship toward lower stimulation frequencies. The Ang 1–7/DIZE effects on twitch and tetanic force were completely blocked by A779, a MasR antagonist, and were not observed in MasR−/− muscles. Ang 1–7 reduced the extent of membrane depolarization, fully prevented the loss of membrane excitability, and maintained the action potential overshoot in denervated muscles. Ang 1–7 had no effect on the changes in α-actin, myosin, or MuRF-1, atrogin-1 protein content or the content of total or phosphorylated Akt, S6, and 4EPB. This is the first study that provides evidence that Ang 1–7 maintains normal muscle function in terms of maximum force and membrane excitability during 14- and 28-d periods after denervation.
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Affiliation(s)
- Hind Albadrani
- University of Ottawa, Department of Cellular and Molecular Medicine, Ottawa, Ontario, Canada.,Majmaah University, Department of Medical Laboratory Sciences, Al Majma'ah, Saudi Arabia
| | - T Ammar
- University of Ottawa, Department of Cellular and Molecular Medicine, Ottawa, Ontario, Canada
| | - Michael Bader
- Max-Delbrück Center for Molecular Medicine, Berlin-Buch, Germany.,University of Lübeck, Institute for Biology, Lübeck, Germany.,Charité University Medicine, Berlin, Germany.,German Center for Cardiovascular Research, Berlin, Germany
| | - Jean-Marc Renaud
- University of Ottawa, Department of Cellular and Molecular Medicine, Ottawa, Ontario, Canada
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29
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Hodson N, Mazzulla M, Holowaty MNH, Kumbhare D, Moore DR. RPS6 phosphorylation occurs to a greater extent in the periphery of human skeletal muscle fibers, near focal adhesions, after anabolic stimuli. Am J Physiol Cell Physiol 2021; 322:C94-C110. [PMID: 34852208 DOI: 10.1152/ajpcell.00357.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Following anabolic stimuli (mechanical loading and/or amino acid provision) the mechanistic target of rapamycin complex 1 (mTORC1), a master regulator of protein synthesis, translocates toward the cell periphery. However, it is unknown if mTORC1-mediated phosphorylation events occur in these peripheral regions or prior to translocation (i.e. in central regions). We therefore aimed to determine the cellular location of a mTORC1-mediated phosphorylation event, RPS6Ser240/244, in human skeletal muscle following anabolic stimuli. Fourteen young, healthy males either ingested a protein-carbohydrate beverage (0.25g/kg protein, 0.75g/kg carbohydrate) alone (n=7;23±5yrs;76.8±3.6kg;13.6±3.8%BF, FED) or following a whole-body resistance exercise bout (n=7;22±2yrs;78.1±3.6kg;12.2±4.9%BF, EXFED). Vastus lateralis muscle biopsies were obtained at rest (PRE) and 120 and 300min following anabolic stimuli. RPS6Ser240/244 phosphorylation measured by immunofluorescent staining or immunoblot was positively correlated (r=0.76, p<0.001). Peripheral staining intensity of p-RPS6Ser240/244 increased above PRE in both FED and EXFED at 120min (~54% and ~138% respectively, p<0.05) but was greater in EXFED at both post-stimuli time points (p<0.05). The peripheral-central ratio of p-RPS6240/244 staining displayed a similar pattern, even when corrected for total RPS6 distribution, suggesting RPS6 phosphorylation occurs to a greater extent in the periphery of fibers. Moreover, p-RPS6Ser240/244 intensity within paxillin-positive regions, a marker of focal adhesion complexes, was elevated at 120min irrespective of stimulus (p=0.006) before returning to PRE at 300min. These data confirm that RPS6Ser240/244 phosphorylation occurs in the region of human muscle fibers to which mTOR translocates following anabolic stimuli and identifies focal adhesion complexes as a potential site of mTORC1 regulation in vivo.
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Affiliation(s)
- Nathan Hodson
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Michael Mazzulla
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | - Maksym N H Holowaty
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
| | | | - Daniel R Moore
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada
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30
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Aby K, Antony R, Eichholz M, Srinivasan R, Li Y. Enhanced pro-BDNF-p75NTR pathway activity in denervated skeletal muscle. Life Sci 2021; 286:120067. [PMID: 34678261 PMCID: PMC8595791 DOI: 10.1016/j.lfs.2021.120067] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 10/07/2021] [Accepted: 10/15/2021] [Indexed: 12/29/2022]
Abstract
AIMS Brain derived neurotrophic factor (BDNF) and the related receptors TrkB and p75NTR are expressed in skeletal muscle, yet their functions remain to be fully understood. Skeletal muscle denervation, which occurs in spinal injury, peripheral neuropathies, and aging, negatively affects muscle mass and function. In this study, we wanted to understand the role of BDNF, TrkB, and p75NTR in denervation-induced adverse effects on skeletal muscle. MAIN METHODS Mice with unilateral sciatic denervation were used. Protein levels of pro- and mature BDNF, TrkB, p75NTR, activations of their downstream signaling pathways, and inflammation in the control and denervated muscle were measured with Western blot and tissue staining. Treatment with a p75NTR inhibitor and BDNF skeletal muscle specific knockout in mice were used to examine the role of p75NTR and pro-BDNF. KEY FINDINGS In denervated muscle, pro-BDNF and p75NTR were significantly upregulated, and JNK and NF-kB, two major downstream signaling pathways of p75NTR, were activated, along with muscle atrophy and inflammation. Inhibition of p75NTR using LM11A-31 significantly reduced JNK activation and inflammatory cytokines in the denervated muscle. Moreover, skeletal muscle specific knockout of BDNF reduced pro-BDNF level, JNK activation and inflammation in the denervated muscle. SIGNIFICANCE These results reveal for the first time that the upregulation of pro-BDNF and activation of p75NTR pathway are involved in denervation-induced inflammation in skeletal muscle. The results suggest that inhibition of pro-BDNF-p75NTR pathway can be a new target to treat skeletal muscle inflammation.
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Affiliation(s)
- Katherine Aby
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA
| | - Ryan Antony
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA
| | - Mary Eichholz
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA
| | - Rekha Srinivasan
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA
| | - Yifan Li
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD 57069, USA.
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31
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Yang BA, Castor-Macias J, Fraczek P, Cornett A, Brown LA, Kim M, Brooks SV, Lombaert IMA, Lee JH, Aguilar CA. Sestrins regulate muscle stem cell metabolic homeostasis. Stem Cell Reports 2021; 16:2078-2088. [PMID: 34388363 PMCID: PMC8452514 DOI: 10.1016/j.stemcr.2021.07.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 01/20/2023] Open
Abstract
The health and homeostasis of skeletal muscle are preserved by a population of tissue-resident muscle stem cells (MuSCs) that maintain a state of mitotic and metabolic quiescence in adult tissues. The capacity of MuSCs to preserve the quiescent state declines with aging and metabolic insults, promoting premature activation and stem cell exhaustion. Sestrins are a class of stress-inducible proteins that act as antioxidants and inhibit the activation of the mammalian target of rapamycin complex 1 (mTORC1) signaling complex. Despite these pivotal roles, the role of Sestrins has not been explored in adult stem cells. We show that SESTRIN1,2 loss results in hyperactivation of the mTORC1 complex, increased propensity to enter the cell cycle, and shifts in metabolic flux. Aged SESTRIN1,2 knockout mice exhibited loss of MuSCs and a reduced ability to regenerate injured muscle. These findings demonstrate that Sestrins help maintain metabolic pathways in MuSCs that protect quiescence against aging.
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Affiliation(s)
- Benjamin A Yang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jesus Castor-Macias
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Paula Fraczek
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ashley Cornett
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA; Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Lemuel A Brown
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Myungjin Kim
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Susan V Brooks
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Isabelle M A Lombaert
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA; Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jun Hee Lee
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carlos A Aguilar
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA; Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI 48109, USA.
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Deleyto-Seldas N, Efeyan A. The mTOR-Autophagy Axis and the Control of Metabolism. Front Cell Dev Biol 2021; 9:655731. [PMID: 34277603 PMCID: PMC8281972 DOI: 10.3389/fcell.2021.655731] [Citation(s) in RCA: 117] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 05/19/2021] [Indexed: 12/12/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR), master regulator of cellular metabolism, exists in two distinct complexes: mTOR complex 1 and mTOR complex 2 (mTORC1 and 2). MTORC1 is a master switch for most energetically onerous processes in the cell, driving cell growth and building cellular biomass in instances of nutrient sufficiency, and conversely, allowing autophagic recycling of cellular components upon nutrient limitation. The means by which the mTOR kinase blocks autophagy include direct inhibition of the early steps of the process, and the control of the lysosomal degradative capacity of the cell by inhibiting the transactivation of genes encoding structural, regulatory, and catalytic factors. Upon inhibition of mTOR, autophagic recycling of cellular components results in the reactivation of mTORC1; thus, autophagy lies both downstream and upstream of mTOR. The functional relationship between the mTOR pathway and autophagy involves complex regulatory loops that are significantly deciphered at the cellular level, but incompletely understood at the physiological level. Nevertheless, genetic evidence stemming from the use of engineered strains of mice has provided significant insight into the overlapping and complementary metabolic effects that physiological autophagy and the control of mTOR activity exert during fasting and nutrient overload.
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Affiliation(s)
- Nerea Deleyto-Seldas
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Center (CNIO), Madrid, Spain
| | - Alejo Efeyan
- Metabolism and Cell Signaling Laboratory, Spanish National Cancer Research Center (CNIO), Madrid, Spain
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33
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Soendenbroe C, Andersen JL, Mackey AL. Muscle-nerve communication and the molecular assessment of human skeletal muscle denervation with aging. Am J Physiol Cell Physiol 2021; 321:C317-C329. [PMID: 34161153 DOI: 10.1152/ajpcell.00174.2021] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Muscle fiber denervation is a major contributor to the decline in physical function observed with aging. Denervation can occur through breakdown of the neuromuscular junctions (NMJ) itself, affecting only that particular fiber, or through the death of a motor neuron, which can lead to a loss of all the muscle fibers in that motor unit. In this review, we discuss the muscle-nerve relationship, where signaling from both the motor neuron and the muscle fiber is required for maximal preservation of neuromuscular function in old age. Physical activity is likely to be the most important single factor that can contribute to this preservation. Furthermore, we propose that inactivity is not an innocent bystander, but plays an active role in denervation through the production of signals hostile to neuron survival. Investigating denervation in human muscle tissue samples is challenging due to the shared protein profile of regenerating and denervated muscle fibers. In this review, we provide a detailed overview of the key traits observed in immunohistochemical preparations of muscle biopsies from healthy, young, and elderly individuals. Overall, a combination of assessing tissue samples, circulating biomarkers, and electrophysiological assessments in humans will prove fruitful in the quest to gain more understanding of denervation of skeletal muscle. In addition, cell culture models represent a valuable tool in the search for key signaling factors exchanged between muscle and nerve, and which exercise has the capacity to alter.
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Affiliation(s)
- Casper Soendenbroe
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Jesper L Andersen
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Abigail L Mackey
- Department of Orthopedic Surgery, Institute of Sports Medicine Copenhagen, Copenhagen University Hospital - Bispebjerg and Frederiksberg, Copenhagen, Denmark.,Xlab, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Medicine, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
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34
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Memme JM, Slavin M, Moradi N, Hood DA. Mitochondrial Bioenergetics and Turnover during Chronic Muscle Disuse. Int J Mol Sci 2021; 22:ijms22105179. [PMID: 34068411 PMCID: PMC8153634 DOI: 10.3390/ijms22105179] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 12/15/2022] Open
Abstract
Periods of muscle disuse promote marked mitochondrial alterations that contribute to the impaired metabolic health and degree of atrophy in the muscle. Thus, understanding the molecular underpinnings of muscle mitochondrial decline with prolonged inactivity is of considerable interest. There are translational applications to patients subjected to limb immobilization following injury, illness-induced bed rest, neuropathies, and even microgravity. Studies in these patients, as well as on various pre-clinical rodent models have elucidated the pathways involved in mitochondrial quality control, such as mitochondrial biogenesis, mitophagy, fission and fusion, and the corresponding mitochondrial derangements that underlie the muscle atrophy that ensues from inactivity. Defective organelles display altered respiratory function concurrent with increased accumulation of reactive oxygen species, which exacerbate myofiber atrophy via degradative pathways. The preservation of muscle quality and function is critical for maintaining mobility throughout the lifespan, and for the prevention of inactivity-related diseases. Exercise training is effective in preserving muscle mass by promoting favourable mitochondrial adaptations that offset the mitochondrial dysfunction, which contributes to the declines in muscle and whole-body metabolic health. This highlights the need for further investigation of the mechanisms in which mitochondria contribute to disuse-induced atrophy, as well as the specific molecular targets that can be exploited therapeutically.
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Affiliation(s)
| | | | | | - David A. Hood
- Correspondence: ; Tel.: +1-(416)-736-2100 (ext. 66640)
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35
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You JS, Kim K, Steinert ND, Chen J, Hornberger TA. mTORC1 mediates fiber type-specific regulation of protein synthesis and muscle size during denervation. Cell Death Discov 2021; 7:74. [PMID: 33846288 PMCID: PMC8042034 DOI: 10.1038/s41420-021-00460-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/18/2021] [Accepted: 03/25/2021] [Indexed: 02/07/2023] Open
Abstract
Skeletal muscle denervation occurs in diverse conditions and causes severe muscle atrophy. Signaling by mammalian target of rapamycin complex 1 (mTORC1) plays a central role in the maintenance of skeletal muscle mass by regulating net protein balance; yet, its role in denervation-induced atrophy is unclear. In this study, by using skeletal muscle-specific and inducible raptor knockout mice, we demonstrate that signaling through mTORC1 is activated during denervation and plays an essential role in mitigating the atrophy of non-type IIB muscle fibers. Measurements of protein synthesis rates of individual fibers suggest that denervation increases protein synthesis specifically in non-type IIB muscle fibers and that mTORC1 is required for this event. Furthermore, denervation induced a more pronounced increase in the level of phosphorylated ribosomal S6 protein in non-type IIB muscle fibers than in type IIB muscle fibers. Collectively, our results unveil a novel role for mTORC1 in mediating a fiber type-specific regulation of muscle size and protein synthesis during denervation.
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Affiliation(s)
- Jae-Sung You
- Department of Comparative Biosciences in the School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Kookjoo Kim
- Department of Comparative Biosciences in the School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Nathaniel D Steinert
- Department of Comparative Biosciences in the School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Jie Chen
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Troy A Hornberger
- Department of Comparative Biosciences in the School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.
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36
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Schiaffino S, Reggiani C, Akimoto T, Blaauw B. Molecular Mechanisms of Skeletal Muscle Hypertrophy. J Neuromuscul Dis 2021; 8:169-183. [PMID: 33216041 PMCID: PMC8075408 DOI: 10.3233/jnd-200568] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Skeletal muscle hypertrophy can be induced by hormones and growth factors acting directly as positive regulators of muscle growth or indirectly by neutralizing negative regulators, and by mechanical signals mediating the effect of resistance exercise. Muscle growth during hypertrophy is controlled at the translational level, through the stimulation of protein synthesis, and at the transcriptional level, through the activation of ribosomal RNAs and muscle-specific genes. mTORC1 has a central role in the regulation of both protein synthesis and ribosomal biogenesis. Several transcription factors and co-activators, including MEF2, SRF, PGC-1α4, and YAP promote the growth of the myofibers. Satellite cell proliferation and fusion is involved in some but not all muscle hypertrophy models.
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Affiliation(s)
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Italy.,Science and Research Centre Koper, Institute for Kinesiology Research, Koper, Slovenia
| | | | - Bert Blaauw
- Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Biomedical Sciences, University of Padova, Italy
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37
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Okun JG, Rusu PM, Chan AY, Wu Y, Yap YW, Sharkie T, Schumacher J, Schmidt KV, Roberts-Thomson KM, Russell RD, Zota A, Hille S, Jungmann A, Maggi L, Lee Y, Blüher M, Herzig S, Keske MA, Heikenwalder M, Müller OJ, Rose AJ. Liver alanine catabolism promotes skeletal muscle atrophy and hyperglycaemia in type 2 diabetes. Nat Metab 2021; 3:394-409. [PMID: 33758419 DOI: 10.1038/s42255-021-00369-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 02/18/2021] [Indexed: 01/31/2023]
Abstract
Both obesity and sarcopenia are frequently associated in ageing, and together may promote the progression of related conditions such as diabetes and frailty. However, little is known about the pathophysiological mechanisms underpinning this association. Here we show that systemic alanine metabolism is linked to glycaemic control. We find that expression of alanine aminotransferases is increased in the liver in mice with obesity and diabetes, as well as in humans with type 2 diabetes. Hepatocyte-selective silencing of both alanine aminotransferase enzymes in mice with obesity and diabetes retards hyperglycaemia and reverses skeletal muscle atrophy through restoration of skeletal muscle protein synthesis. Mechanistically, liver alanine catabolism driven by chronic glucocorticoid and glucagon signalling promotes hyperglycaemia and skeletal muscle wasting. We further provide evidence for amino acid-induced metabolic cross-talk between the liver and skeletal muscle in ex vivo experiments. Taken together, we reveal a metabolic inter-tissue cross-talk that links skeletal muscle atrophy and hyperglycaemia in type 2 diabetes.
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Affiliation(s)
- Jürgen G Okun
- Division of Inherited Metabolic Diseases, University Children's Hospital, Heidelberg, Germany
| | - Patricia M Rusu
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Andrea Y Chan
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Yuqin Wu
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Yann W Yap
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Thomas Sharkie
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Jonas Schumacher
- Division of Molecular Metabolic Control, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Kathrin V Schmidt
- Division of Inherited Metabolic Diseases, University Children's Hospital, Heidelberg, Germany
| | - Katherine M Roberts-Thomson
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - Ryan D Russell
- Department of Health and Human Performance, College of Health Professions, University of Texas Rio Grande Valley, Brownsville, TX, USA
| | - Annika Zota
- Division of Molecular Metabolic Control, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Institute for Diabetes and Cancer (IDC), Helmholtz Center Munich, Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine I, Heidelberg University Hospital and Chair Molecular Metabolic Control, Technical University Munich, Neuherberg, Germany
| | - Susanne Hille
- Department of Internal Medicine III, University of Kiel, Kiel, Germany
- German Center for Cardiovascular Research (DZHK), Heidelberg and Kiel sites, Germany
| | - Andreas Jungmann
- German Center for Cardiovascular Research (DZHK), Heidelberg and Kiel sites, Germany
- Department of Internal Medicine III, University Hospital Heidelberg, Heidelberg, Germany
| | - Ludovico Maggi
- Division of Molecular Metabolic Control, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Young Lee
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Matthias Blüher
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig, Leipzig, Germany
| | - Stephan Herzig
- Division of Molecular Metabolic Control, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Institute for Diabetes and Cancer (IDC), Helmholtz Center Munich, Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine I, Heidelberg University Hospital and Chair Molecular Metabolic Control, Technical University Munich, Neuherberg, Germany
| | - Michelle A Keske
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - Mathias Heikenwalder
- Division of Chronic Inflammation and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Oliver J Müller
- Department of Internal Medicine III, University of Kiel, Kiel, Germany
- German Center for Cardiovascular Research (DZHK), Heidelberg and Kiel sites, Germany
| | - Adam J Rose
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.
- Division of Molecular Metabolic Control, German Cancer Research Center (DKFZ), Heidelberg, Germany.
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38
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Ohkawara B, Ito M, Ohno K. Secreted Signaling Molecules at the Neuromuscular Junction in Physiology and Pathology. Int J Mol Sci 2021; 22:ijms22052455. [PMID: 33671084 PMCID: PMC7957818 DOI: 10.3390/ijms22052455] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/22/2021] [Accepted: 02/25/2021] [Indexed: 02/08/2023] Open
Abstract
Signal transduction at the neuromuscular junction (NMJ) is affected in many human diseases, including congenital myasthenic syndromes (CMS), myasthenia gravis, Lambert–Eaton myasthenic syndrome, Isaacs’ syndrome, Schwartz–Jampel syndrome, Fukuyama-type congenital muscular dystrophy, amyotrophic lateral sclerosis, and sarcopenia. The NMJ is a prototypic cholinergic synapse between the motor neuron and the skeletal muscle. Synaptogenesis of the NMJ has been extensively studied, which has also been extrapolated to further understand synapse formation in the central nervous system. Studies of genetically engineered mice have disclosed crucial roles of secreted molecules in the development and maintenance of the NMJ. In this review, we focus on the secreted signaling molecules which regulate the clustering of acetylcholine receptors (AChRs) at the NMJ. We first discuss the signaling pathway comprised of neural agrin and its receptors, low-density lipoprotein receptor-related protein 4 (Lrp4) and muscle-specific receptor tyrosine kinase (MuSK). This pathway drives the clustering of acetylcholine receptors (AChRs) to ensure efficient signal transduction at the NMJ. We also discuss three secreted molecules (Rspo2, Fgf18, and connective tissue growth factor (Ctgf)) that we recently identified in the Wnt/β-catenin and fibroblast growth factors (FGF) signaling pathways. The three secreted molecules facilitate the clustering of AChRs by enhancing the agrin-Lrp4-MuSK signaling pathway.
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Affiliation(s)
- Bisei Ohkawara
- Correspondence: ; Tel.: +81-52-744-2447; Fax: +81-52-744-2449
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39
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He J, Liu J, Huang Y, Tang X, Xiao H, Hu Z. Oxidative Stress, Inflammation, and Autophagy: Potential Targets of Mesenchymal Stem Cells-Based Therapies in Ischemic Stroke. Front Neurosci 2021; 15:641157. [PMID: 33716657 PMCID: PMC7952613 DOI: 10.3389/fnins.2021.641157] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 01/26/2021] [Indexed: 12/14/2022] Open
Abstract
Ischemic stroke is a leading cause of death worldwide; currently available treatment approaches for ischemic stroke are to restore blood flow, which reduce disability but are time limited. The interruption of blood flow in ischemic stroke contributes to intricate pathophysiological processes. Oxidative stress and inflammatory activity are two early events in the cascade of cerebral ischemic injury. These two factors are reciprocal causation and directly trigger the development of autophagy. Appropriate autophagy activity contributes to brain recovery by reducing oxidative stress and inflammatory activity, while autophagy dysfunction aggravates cerebral injury. Abundant evidence demonstrates the beneficial impact of mesenchymal stem cells (MSCs) and secretome on cerebral ischemic injury. MSCs reduce oxidative stress through suppressing reactive oxygen species (ROS) and reactive nitrogen species (RNS) generation and transferring healthy mitochondria to damaged cells. Meanwhile, MSCs exert anti-inflammation properties by the production of cytokines and extracellular vesicles, inhibiting proinflammatory cytokines and inflammatory cells activation, suppressing pyroptosis, and alleviating blood–brain barrier leakage. Additionally, MSCs regulation of autophagy imbalances gives rise to neuroprotection against cerebral ischemic injury. Altogether, MSCs have been a promising candidate for the treatment of ischemic stroke due to their pleiotropic effect.
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Affiliation(s)
- Jialin He
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jianyang Liu
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Yan Huang
- National Health Commission Key Laboratory of Birth Defect for Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
| | - Xiangqi Tang
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Han Xiao
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Zhiping Hu
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
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40
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Gorza L, Sorge M, Seclì L, Brancaccio M. Master Regulators of Muscle Atrophy: Role of Costamere Components. Cells 2021; 10:cells10010061. [PMID: 33401549 PMCID: PMC7823551 DOI: 10.3390/cells10010061] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 12/11/2022] Open
Abstract
The loss of muscle mass and force characterizes muscle atrophy in several different conditions, which share the expression of atrogenes and the activation of their transcriptional regulators. However, attempts to antagonize muscle atrophy development in different experimental contexts by targeting contributors to the atrogene pathway showed partial effects in most cases. Other master regulators might independently contribute to muscle atrophy, as suggested by our recent evidence about the co-requirement of the muscle-specific chaperone protein melusin to inhibit unloading muscle atrophy development. Furthermore, melusin and other muscle mass regulators, such as nNOS, belong to costameres, the macromolecular complexes that connect sarcolemma to myofibrils and to the extracellular matrix, in correspondence with specific sarcomeric sites. Costameres sense a mechanical load and transduce it both as lateral force and biochemical signals. Recent evidence further broadens this classic view, by revealing the crucial participation of costameres in a sarcolemmal “signaling hub” integrating mechanical and humoral stimuli, where mechanical signals are coupled with insulin and/or insulin-like growth factor stimulation to regulate muscle mass. Therefore, this review aims to enucleate available evidence concerning the early involvement of costamere components and additional putative master regulators in the development of major types of muscle atrophy.
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Affiliation(s)
- Luisa Gorza
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy
- Correspondence:
| | - Matteo Sorge
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
| | - Laura Seclì
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
| | - Mara Brancaccio
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Torino, Italy; (M.S.); (L.S.); (M.B.)
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41
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Okamura T, Okada H, Hashimoto Y, Majima S, Senmaru T, Nakanishi N, Asano M, Yamazaki M, Hamaguchi M, Fukui M. Let-7e-5p Regulates IGF2BP2, and Induces Muscle Atrophy. Front Endocrinol (Lausanne) 2021; 12:791363. [PMID: 35002969 PMCID: PMC8741024 DOI: 10.3389/fendo.2021.791363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/06/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND AIMS To understand the role of microRNAs in muscle atrophy caused by androgen-depletion, we performed microarray analysis of microRNA expression in the skeletal muscles of Sham, orchiectomized (ORX), and androgen-treated ORX mice. METHODS To clarify role and mechanisms of let-7e-5p in the muscle, the effect of let-7e-5p overexpression or knockdown on the expression of myosin heavy chain, glucose uptake, and mitochondrial function was investigated in C2C12 myotube cells. Moreover, we examined serum let-7e-5p levels among male subjects with type 2 diabetes. RESULTS We found that the expression of the miRNA, lethal (let)-7e-5p was significantly lower in ORX mice than that in Sham mice (p = 0.027); however, let-7e-5p expression in androgen-treated ORX mice was higher (p = 0.047). Suppression of let-7e-5p significantly upregulated the expression of myosin heavy chain, glucose uptake, and mitochondrial function. Real-time PCR revealed a possible regulation involving let-7e-5p and Igf2bp2 mRNA and protein in C2C12 cells. The serum let-7e-5p levels were significantly lower, which might be in compensation, in subjects with decreased muscle mass compared to subjects without decreased muscle mass. Let-7e-5p downregulates the expression of Igf2bp2 in myotube cells and inhibits the growth of the myosin heavy chain. CONCLUSIONS Based on our study, serum level of let-7e-5p may be used as a potential diagnostic marker for muscle atrophy.
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Affiliation(s)
- Takuro Okamura
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hiroshi Okada
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
- Department of Diabetes and Endocrinology, Matsushita Memorial Hospital, Moriguchi, Japan
| | - Yoshitaka Hashimoto
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Saori Majima
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Takafumi Senmaru
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Naoko Nakanishi
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Mai Asano
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Masahiro Yamazaki
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Masahide Hamaguchi
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Michiaki Fukui
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
- *Correspondence: Michiaki Fukui,
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42
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Tu WY, Xu W, Zhang K, Shen C. Whole-mount staining of neuromuscular junctions in adult mouse diaphragms with a sandwich-like apparatus. J Neurosci Methods 2020; 350:109016. [PMID: 33316317 DOI: 10.1016/j.jneumeth.2020.109016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/22/2020] [Accepted: 11/26/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Investigation of neuromuscular junction (NMJ) morphology by immunochemistry can provide important insights into the physiological and pathological status of neuromuscular disorders. Sectioning and muscle fiber tearing are commonly required to prepare experimentally accessible samples, while muscles that are flat and thin can be investigated with whole-mount immunohistochemistry for a comprehensive overview of the entire innervation pattern. The diaphragm is important for respiratory function and one of the flat muscles frequently used for studying neuromuscular development as well as neuromuscular pathology. Nevertheless, techniques for reliable whole-mount immunolabeling of adult diaphragms are lacking, mainly due to the poor tissue permeability of labeling reagents. An effective approach for researchers to be able to comprehensively visualize and characterize NMJ defects of the adult diaphragm in mouse models is therefore of clear importance. NEW METHOD This protocol demonstrates that the diaphragm can be thinned and spread out under even pressure using two Perspex boards for better whole-mount immunostaining. RESULTS The expanded mouse diaphragm allows the comprehensive assessment of a number of NMJ phenotypes. COMPARISON WITH EXISTING METHODS Most peer-reviewed and online protocols can be applied to the embryonic diaphragm but fail to show the entire innervation pattern in the adult diaphragm. Our method provides a convenient approach and present a clear innervation pattern that increases the reliability of the assessment of NMJ phenotypes in the diaphragm. CONCLUSIONS This simple method for whole-mount immunostaining of the adult diaphragm will allow researchers to perform a detailed analysis of the neuromuscular system in mouse models.
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Affiliation(s)
- Wen-Yo Tu
- Department of Neurobiology, The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China.
| | - Wentao Xu
- Department of Neurobiology, The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China
| | - Kejing Zhang
- Department of Neurobiology, The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China
| | - Chengyong Shen
- Department of Neurobiology, The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China; Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, School of Medicine, Zhejiang University, Zhejiang, China.
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Rodríguez Cruz PM, Cossins J, Beeson D, Vincent A. The Neuromuscular Junction in Health and Disease: Molecular Mechanisms Governing Synaptic Formation and Homeostasis. Front Mol Neurosci 2020; 13:610964. [PMID: 33343299 PMCID: PMC7744297 DOI: 10.3389/fnmol.2020.610964] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 10/30/2020] [Indexed: 12/28/2022] Open
Abstract
The neuromuscular junction (NMJ) is a highly specialized synapse between a motor neuron nerve terminal and its muscle fiber that are responsible for converting electrical impulses generated by the motor neuron into electrical activity in the muscle fibers. On arrival of the motor nerve action potential, calcium enters the presynaptic terminal, which leads to the release of the neurotransmitter acetylcholine (ACh). ACh crosses the synaptic gap and binds to ACh receptors (AChRs) tightly clustered on the surface of the muscle fiber; this leads to the endplate potential which initiates the muscle action potential that results in muscle contraction. This is a simplified version of the events in neuromuscular transmission that take place within milliseconds, and are dependent on a tiny but highly structured NMJ. Much of this review is devoted to describing in more detail the development, maturation, maintenance and regeneration of the NMJ, but first we describe briefly the most important molecules involved and the conditions that affect their numbers and function. Most important clinically worldwide, are myasthenia gravis (MG), the Lambert-Eaton myasthenic syndrome (LEMS) and congenital myasthenic syndromes (CMS), each of which causes specific molecular defects. In addition, we mention the neurotoxins from bacteria, snakes and many other species that interfere with neuromuscular transmission and cause potentially fatal diseases, but have also provided useful probes for investigating neuromuscular transmission. There are also changes in NMJ structure and function in motor neuron disease, spinal muscle atrophy and sarcopenia that are likely to be secondary but might provide treatment targets. The NMJ is one of the best studied and most disease-prone synapses in the nervous system and it is amenable to in vivo and ex vivo investigation and to systemic therapies that can help restore normal function.
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Affiliation(s)
- Pedro M Rodríguez Cruz
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Judith Cossins
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - David Beeson
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
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Alves PKN, Cruz A, Silva WJ, Labeit S, Moriscot AS. Leucine Supplementation Decreases HDAC4 Expression and Nuclear Localization in Skeletal Muscle Fiber of Rats Submitted to Hindlimb Immobilization. Cells 2020; 9:cells9122582. [PMID: 33276563 PMCID: PMC7761616 DOI: 10.3390/cells9122582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 11/19/2020] [Accepted: 11/26/2020] [Indexed: 02/07/2023] Open
Abstract
In this study we surveyed a rat skeletal muscle RNA-Seq for genes that are induced by hindlimb immobilization and, in turn, become attenuated by leucine supplementation. This approach, in search of leucine-atrophy protection mediating genes, identified histone deacetylase 4 (HDAC4) as highly responsive to both hindlimb immobilization and leucine supplementation. We then examined the impact of leucine on HDAC4 expression, tissue localization, and target genes. A total of 76 male Wistar rats (~280 g) were submitted to hindlimb immobilization and/or leucine supplementation for 3, 7 and 12 days. These animals were euthanized, and soleus muscle was removed for further analysis. RNA-Seq analysis of hindlimb immobilized rats indicated a sharp induction (log2 = 3.4) of HDAC4 expression which was attenuated by leucine supplementation (~50%). Real-time PCR and protein expression analysis by Western blot confirmed increased HDAC4 mRNA after 7 days of hindlimb immobilization and mitigation of induction by leucine supplementation. Regarding the HDAC4 localization, the proportion of positive nuclei was higher in the immobilized group and decreased after leucine supplementation. Also, we found a marked decrease of myogenin and MAFbx-atrogin-1 mRNA levels upon leucine supplementation, while CAMKII and DACH2 mRNA levels were increased by leucine supplementation. Our data suggest that HDAC4 inhibition might be involved in the anti-atrophic effects of leucine.
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Affiliation(s)
- Paula K. N. Alves
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508000, Brazil; (P.K.N.A.); (A.C.); (W.J.S.)
| | - André Cruz
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508000, Brazil; (P.K.N.A.); (A.C.); (W.J.S.)
| | - William J. Silva
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508000, Brazil; (P.K.N.A.); (A.C.); (W.J.S.)
| | - Siegfried Labeit
- Faculty for Clinical Medicine Mannheim of the University of Heidelberg, Institute for Integrative Pathophysiology, Universitätsmedizin Mannheim, 68169 Mannheim, Germany;
- Myomedix GmbH, 69151 Neckargemund, Germany
| | - Anselmo S. Moriscot
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo 05508000, Brazil; (P.K.N.A.); (A.C.); (W.J.S.)
- Correspondence:
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A Role for Caveolin-3 in the Pathogenesis of Muscular Dystrophies. Int J Mol Sci 2020; 21:ijms21228736. [PMID: 33228026 PMCID: PMC7699313 DOI: 10.3390/ijms21228736] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
Caveolae are the cholesterol-rich small invaginations of the plasma membrane present in many cell types including adipocytes, endothelial cells, epithelial cells, fibroblasts, smooth muscles, skeletal muscles and cardiac muscles. They serve as specialized platforms for many signaling molecules and regulate important cellular processes like energy metabolism, lipid metabolism, mitochondria homeostasis, and mechano-transduction. Caveolae can be internalized together with associated cargo. The caveolae-dependent endocytic pathway plays a role in the withdrawal of many plasma membrane components that can be sent for degradation or recycled back to the cell surface. Caveolae are formed by oligomerization of caveolin proteins. Caveolin-3 is a muscle-specific isoform, whose malfunction is associated with several diseases including diabetes, cancer, atherosclerosis, and cardiovascular diseases. Mutations in Caveolin-3 are known to cause muscular dystrophies that are collectively called caveolinopathies. Altered expression of Caveolin-3 is also observed in Duchenne’s muscular dystrophy, which is likely a part of the pathological process leading to muscle weakness. This review summarizes the major functions of Caveolin-3 in skeletal muscles and discusses its involvement in the pathology of muscular dystrophies.
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Chaby LE, Sadik N, Burson NA, Lloyd S, O'Donnel K, Winters J, Conti AC, Liberzon I, Perrine SA. Repeated stress exposure in mid-adolescence attenuates behavioral, noradrenergic, and epigenetic effects of trauma-like stress in early adult male rats. Sci Rep 2020; 10:17935. [PMID: 33087769 PMCID: PMC7578655 DOI: 10.1038/s41598-020-74481-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/30/2020] [Indexed: 12/11/2022] Open
Abstract
Stress in adolescence can regulate vulnerability to traumatic stress in adulthood through region-specific epigenetic activity and catecholamine levels. We hypothesized that stress in adolescence would increase adult trauma vulnerability by impairing extinction-retention, a deficit in PTSD, by (1) altering class IIa histone deacetylases (HDACs), which integrate effects of stress on gene expression, and (2) enhancing norepinephrine in brain regions regulating cognitive effects of trauma. We investigated the effects of adolescent-stress on adult vulnerability to severe stress using the single-prolonged stress (SPS) model in male rats. Rats were exposed to either (1) adolescent-stress (33-35 postnatal days) then SPS (58-60 postnatal days; n = 14), or (2) no adolescent-stress and SPS (58-60 postnatal days; n = 14), or (3) unstressed conditions (n = 8). We then measured extinction-retention, norepinephrine, HDAC4, and HDAC5. As expected, SPS exposure induced an extinction-retention deficit. Adolescent-stress prior to SPS eliminated this deficit, suggesting adolescent-stress conferred resiliency to adult severe stress. Adolescent-stress also conferred region-specific resilience to norepinephrine changes. HDAC4 and HDAC5 were down-regulated following SPS, and these changes were also modulated by adolescent-stress. Regulation of HDAC levels was consistent with the pattern of cognitive effects of SPS; only animals exposed to SPS without adolescent-stress exhibited reduced HDAC4 and HDAC5 in the prelimbic cortex, hippocampus, and striatum. Thus, HDAC regulation caused by severe stress in adulthood interacts with stress history such that seemingly conflicting reports describing effects of adolescent stress on adult PTSD vulnerability may stem in part from dynamic HDAC changes following trauma that are shaped by adolescent stress history.
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MESH Headings
- Adolescent
- Adolescent Behavior/physiology
- Adolescent Behavior/psychology
- Animals
- Brain/metabolism
- Disease Models, Animal
- Epigenesis, Genetic
- Extinction, Psychological/physiology
- Histone Deacetylases/metabolism
- Humans
- Male
- Norepinephrine/metabolism
- Psychology, Adolescent
- Rats, Sprague-Dawley
- Retention, Psychology/physiology
- Stress Disorders, Post-Traumatic/etiology
- Stress Disorders, Post-Traumatic/genetics
- Stress Disorders, Post-Traumatic/metabolism
- Stress Disorders, Post-Traumatic/psychology
- Stress, Psychological
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Affiliation(s)
- Lauren E Chaby
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA.
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA.
| | - Nareen Sadik
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA
| | - Nicole A Burson
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA
| | - Scott Lloyd
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA
- Research Service, John D. Dingell VA Medical Center, Detroit, MI, USA
| | - Kelly O'Donnel
- Department of Psychology, University of Colorado, Colorado Springs, CO, USA
| | - Jesse Winters
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA
| | - Alana C Conti
- Research Service, John D. Dingell VA Medical Center, Detroit, MI, USA
- Department of Neurosurgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Israel Liberzon
- Department of Psychiatry, Texas A&M College of Medicine, Bryan, TX, USA
| | - Shane A Perrine
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI, USA
- Research Service, John D. Dingell VA Medical Center, Detroit, MI, USA
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The neuromuscular junction is a focal point of mTORC1 signaling in sarcopenia. Nat Commun 2020; 11:4510. [PMID: 32908143 PMCID: PMC7481251 DOI: 10.1038/s41467-020-18140-1] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 08/05/2020] [Indexed: 12/21/2022] Open
Abstract
With human median lifespan extending into the 80s in many developed countries, the societal burden of age-related muscle loss (sarcopenia) is increasing. mTORC1 promotes skeletal muscle hypertrophy, but also drives organismal aging. Here, we address the question of whether mTORC1 activation or suppression is beneficial for skeletal muscle aging. We demonstrate that chronic mTORC1 inhibition with rapamycin is overwhelmingly, but not entirely, positive for aging mouse skeletal muscle, while genetic, muscle fiber-specific activation of mTORC1 is sufficient to induce molecular signatures of sarcopenia. Through integration of comprehensive physiological and extensive gene expression profiling in young and old mice, and following genetic activation or pharmacological inhibition of mTORC1, we establish the phenotypically-backed, mTORC1-focused, multi-muscle gene expression atlas, SarcoAtlas (https://sarcoatlas.scicore.unibas.ch/), as a user-friendly gene discovery tool. We uncover inter-muscle divergence in the primary drivers of sarcopenia and identify the neuromuscular junction as a focal point of mTORC1-driven muscle aging.
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Castets P, Ham DJ, Rüegg MA. The TOR Pathway at the Neuromuscular Junction: More Than a Metabolic Player? Front Mol Neurosci 2020; 13:162. [PMID: 32982690 PMCID: PMC7485269 DOI: 10.3389/fnmol.2020.00162] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/05/2020] [Indexed: 12/18/2022] Open
Abstract
The neuromuscular junction (NMJ) is the chemical synapse connecting motor neurons and skeletal muscle fibers. NMJs allow all voluntary movements, and ensure vital functions like breathing. Changes in the structure and function of NMJs are hallmarks of numerous pathological conditions that affect muscle function including sarcopenia, the age-related loss of muscle mass and function. However, the molecular mechanisms leading to the morphological and functional perturbations in the pre- and post-synaptic compartments of the NMJ remain poorly understood. Here, we discuss the role of the metabolic pathway associated to the kinase TOR (Target of Rapamycin) in the development, maintenance and alterations of the NMJ. This is of particular interest as the TOR pathway has been implicated in aging, but its role at the NMJ is still ill-defined. We highlight the respective functions of the two TOR-associated complexes, TORC1 and TORC2, and discuss the role of localized protein synthesis and autophagy regulation in motor neuron terminals and sub-synaptic regions of muscle fibers and their possible effects on NMJ maintenance.
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Affiliation(s)
- Perrine Castets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Shen Y, Zhang Q, Huang Z, Zhu J, Qiu J, Ma W, Yang X, Ding F, Sun H. Isoquercitrin Delays Denervated Soleus Muscle Atrophy by Inhibiting Oxidative Stress and Inflammation. Front Physiol 2020; 11:988. [PMID: 32903465 PMCID: PMC7435639 DOI: 10.3389/fphys.2020.00988] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 07/20/2020] [Indexed: 12/19/2022] Open
Abstract
Although denervated muscle atrophy is common, the underlying molecular mechanism remains unelucidated. We have previously found that oxidative stress and inflammatory response may be early events that trigger denervated muscle atrophy. Isoquercitrin is a biologically active flavonoid with antioxidative and anti-inflammatory properties. The present study investigated the effect of isoquercitrin on denervated soleus muscle atrophy and its possible molecular mechanisms. We found that isoquercitrin was effective in alleviating soleus muscle mass loss following denervation in a dose-dependent manner. Isoquercitrin demonstrated the optimal protective effect at 20 mg/kg/d, which was the dose used in subsequent experiments. To further explore the protective effect of isoquercitrin on denervated soleus muscle atrophy, we analyzed muscle proteolysis via the ubiquitin-proteasome pathway, mitophagy, and muscle fiber type conversion. Isoquercitrin significantly inhibited the denervation-induced overexpression of two muscle-specific ubiquitin ligases—muscle RING finger 1 (MuRF1) and muscle atrophy F-box (MAFbx), and reduced the degradation of myosin heavy chains (MyHCs) in the target muscle. Following isoquercitrin treatment, mitochondrial vacuolation and autophagy were inhibited, as evidenced by reduced level of autophagy-related proteins (ATG7, BNIP3, LC3B, and PINK1); slow-to-fast fiber type conversion in the target muscle was delayed via triggering expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α); and the production of reactive oxygen species (ROS) in the target muscle was reduced, which might be associated with the upregulation of antioxidant factors (SOD1, SOD2, NRF2, NQO1, and HO1) and the downregulation of ROS production-related factors (Nox2, Nox4, and DUOX1). Furthermore, isoquercitrin treatment reduced the levels of inflammatory factors—interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α)—in the target muscle and inactivated the JAK/STAT3 signaling pathway. Overall, isoquercitrin may alleviate soleus muscle atrophy and mitophagy and reverse the slow-to-fast fiber type conversion following denervation via inhibition of oxidative stress and inflammatory response. Our study findings enrich the knowledge regarding the molecular regulatory mechanisms of denervated muscle atrophy and provide a scientific basis for isoquercitrin as a protective drug for the prevention and treatment of denervated muscle atrophy.
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Affiliation(s)
- Yuntian Shen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Qiuyu Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Ziwei Huang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Jianwei Zhu
- Department of Orthopedics, Affiliated Hospital of Nantong University, Nantong, China
| | - Jiayi Qiu
- School of Nursing, Nantong University, Nantong, China
| | - Wenjing Ma
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Xiaoming Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Fei Ding
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Hualin Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China
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Tokinoya K, Shirai T, Ota Y, Takemasa T, Takekoshi K. Denervation-induced muscle atrophy suppression in renalase-deficient mice via increased protein synthesis. Physiol Rep 2020; 8:e14475. [PMID: 32741114 PMCID: PMC7395909 DOI: 10.14814/phy2.14475] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/17/2020] [Accepted: 05/12/2020] [Indexed: 12/20/2022] Open
Abstract
Denervation-induced muscle atrophy increases signaling through both protein degradation and synthesis pathways. Renalase is a flavin adenine dinucleotide-dependent amine oxidase that inhibits apoptosis and inflammation and promotes cell survival. This study aimed to elucidate the effect of renalase on denervation-induced muscle atrophy. We used 7-week-old renalase knock-out (KO) mice (a model of denervation-induced muscle atrophy) and wild-type (WT) mice (KO: n = 6, weight = 20-26 g; WT: n = 5, weight = 19-23 g). After their left legs were denervated, these mice were killed 1 week later. KO mice had lighter muscle weight than the WT mice. We observed an increase in molecular signaling through protein degradation pathway as well as oxidative stress in denervated muscles compared with that in sham-operated muscles in both WT and KO mice. Additionally, we also observed the main effect of renalase in WT and KO mice. Mitochondrial oxidative phosphorylation protein content was lower in denervated muscles than in sham-operated muscles in both WT and KO mice. However, a significant difference was noted in the reaction with Akt and p70S6K (components of the protein synthesis pathway) between WT and KO mice. In conclusion, mice with renalase deficiency demonstrated an attenuation of denervation-induced muscle atrophy. This might be related to catecholamines because signaling through the protein synthesis pathway was increased following denervation in renalase KO mice compared with that in WT mice, despite showing no change in signaling through protein degradation pathways.
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Affiliation(s)
- Katsuyuki Tokinoya
- Doctoral Program in Sports MedicineGraduate School of Comprehensive Human SciencesUniversity of TsukubaTsukubaJapan
- Research Fellow of the Japan Society for the Promotion of ScienceTokyoJapan
| | - Takanaga Shirai
- Graduate School of Comprehensive Human SciencesUniversity of TsukubaTsukubaJapan
| | - Yuya Ota
- Graduate School of Comprehensive Human SciencesUniversity of TsukubaTsukubaJapan
| | - Tohru Takemasa
- Faculty of Health and Sport SciencesUniversity of TsukubaTsukubaJapan
| | - Kazuhiro Takekoshi
- Division of Clinical MedicineFaculty of MedicineUniversity of TsukubaTsukubaJapan
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