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Mogharehabed F, Czubryt MP. The role of fibrosis in the pathophysiology of muscular dystrophy. Am J Physiol Cell Physiol 2023; 325:C1326-C1335. [PMID: 37781738 DOI: 10.1152/ajpcell.00196.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Muscular dystrophy exerts significant and dramatic impacts on affected patients, including progressive muscle wasting leading to lung and heart failure, and results in severely curtailed lifespan. Although the focus for many years has been on the dysfunction induced by the loss of function of dystrophin or related components of the striated muscle costamere, recent studies have demonstrated that accompanying pathologies, particularly muscle fibrosis, also contribute adversely to patient outcomes. A significant body of research has now shown that therapeutically targeting these accompanying pathologies via their underlying molecular mechanisms may provide novel approaches to patient management that can complement the current standard of care. In this review, we discuss the interplay between muscle fibrosis and muscular dystrophy pathology. A better understanding of these processes will contribute to improved patient care options, restoration of muscle function, and reduced patient morbidity and mortality.
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Affiliation(s)
- Farnaz Mogharehabed
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Michael P Czubryt
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
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2
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Mukherjee R, Tetri LH, Li SJ, Fajardo G, Ostberg NP, Tsegay KB, Gera K, Cornell TT, Bernstein D, Mochly-Rosen D, Haileselassie B. Drp1/p53 interaction mediates p53 mitochondrial localization and dysfunction in septic cardiomyopathy. J Mol Cell Cardiol 2023; 177:28-37. [PMID: 36841153 PMCID: PMC10358757 DOI: 10.1016/j.yjmcc.2023.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 01/15/2023] [Accepted: 01/16/2023] [Indexed: 02/27/2023]
Abstract
BACKGROUND Previous studies have implicated p53-dependent mitochondrial dysfunction in sepsis induced end organ injury, including sepsis-induced myocardial dysfunction (SIMD). However, the mechanisms behind p53 localization to the mitochondria have not been well established. Dynamin-related protein 1 (Drp1), a mediator of mitochondrial fission, may play a role in p53 mitochondrial localization. Here we examined the role of Drp1/p53 interaction in SIMD using in vitro and murine models of sepsis. METHODS H9c2 cardiomyoblasts and BALB/c mice were exposed to lipopolysaccharide (LPS) to model sepsis phenotype. Pharmacologic inhibitors of Drp1 activation (ψDrp1) and of p53 mitochondrial binding (pifithrin μ, PFTμ) were utilized to assess interaction between Drp1 and p53, and the subsequent downstream impact on mitochondrial morphology and function, cardiomyocyte function, and sepsis phenotype. RESULTS Both in vitro and murine models demonstrated an increase in physical Drp1/p53 interaction following LPS treatment, which was associated with increased p53 mitochondrial localization, and mitochondrial dysfunction. This Drp1/p53 interaction was inhibited by ΨDrp1, suggesting that this interaction is dependent on Drp1 activation. Treatment of H9c2 cells with either ΨDrp1 or PFTμ inhibited the LPS mediated localization of Drp1/p53 to the mitochondria, decreased oxidative stress, improved cellular respiration and ATP production. Similarly, treatment of BALB/c mice with either ΨDrp1 or PFTμ decreased LPS-mediated mitochondrial localization of p53, mitochondrial ROS in cardiac tissue, and subsequently improved cardiomyocyte contractile function and survival. CONCLUSION Drp1/p53 interaction and mitochondrial localization is a key prodrome to mitochondrial damage in SIMD and inhibiting this interaction may serve as a therapeutic target.
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Affiliation(s)
- Riddhita Mukherjee
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Laura H Tetri
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Anesthesia, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sin-Jin Li
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Giovanni Fajardo
- Department of Pediatrics, Division of Cardiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nicolai P Ostberg
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kaleb B Tsegay
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kanika Gera
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Timothy T Cornell
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daniel Bernstein
- Department of Pediatrics, Division of Cardiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Bereketeab Haileselassie
- Department of Pediatrics, Division of Critical Care Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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3
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Donen G, Milad N, Bernatchez P. Humanization of the mdx Mouse Phenotype for Duchenne Muscular Dystrophy Modeling: A Metabolic Perspective. J Neuromuscul Dis 2023; 10:1003-1012. [PMID: 37574742 PMCID: PMC10657711 DOI: 10.3233/jnd-230126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2023] [Indexed: 08/15/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a severe form of muscular dystrophy (MD) that is characterized by early muscle wasting and lethal cardiorespiratory failure. While the mdx mouse is the most common model of DMD, it fails to replicate the severe loss of muscle mass and other complications observed in patients, in part due to the multiple rescue pathways found in mice. This led to several attempts at improving DMD animal models by interfering with these rescue pathways through double transgenic approaches, resulting in more severe phenotypes with mixed relevance to the human pathology. As a growing body of literature depicts DMD as a multi-system metabolic disease, improvements in mdx-based modeling of DMD may be achieved by modulating whole-body metabolism instead of muscle homeostasis. This review provides an overview of the established dual-transgenic approaches that exacerbate the mild mdx phenotype by primarily interfering with muscle homeostasis and highlights how advances in DMD modeling coincide with inducing whole-body metabolic changes. We focus on the DBA2/J strain-based D2.mdx mouse with heightened transforming growth factor (TGF)-β signaling and the dyslipidemic mdx/apolipoprotein E (mdx/ApoE) knock-out (KO) mouse, and summarize how these novel models emulate the metabolic changes observed in DMD.
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Affiliation(s)
| | | | - Pascal Bernatchez
- Correspondence to: Dr. Pascal Bernatchez, Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, 2176 Health Sciences mall, room 217, Vancouver BC, V6T 1Z3, Canada. Tel.: +1 604 806 8346 /Ext.66060; E-mail:
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4
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Almikhlafi MA, Karami MM, Jana A, Alqurashi TM, Majrashi M, Alghamdi BS, Ashraf GM. Mitochondrial Medicine: A Promising Therapeutic Option Against Various Neurodegenerative Disorders. Curr Neuropharmacol 2023; 21:1165-1183. [PMID: 36043795 PMCID: PMC10286591 DOI: 10.2174/1570159x20666220830112408] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/05/2022] [Accepted: 07/14/2022] [Indexed: 11/22/2022] Open
Abstract
Abnormal mitochondrial morphology and metabolic dysfunction have been observed in many neurodegenerative disorders (NDDs). Mitochondrial dysfunction can be caused by aberrant mitochondrial DNA, mutant nuclear proteins that interact with mitochondria directly or indirectly, or for unknown reasons. Since mitochondria play a significant role in neurodegeneration, mitochondriatargeted therapies represent a prosperous direction for the development of novel drug compounds that can be used to treat NDDs. This review gives a brief description of how mitochondrial abnormalities lead to various NDDs such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. We further explore the promising therapeutic effectiveness of mitochondria- directed antioxidants, MitoQ, MitoVitE, MitoPBN, and dimebon. We have also discussed the possibility of mitochondrial gene therapy as a therapeutic option for these NDDs.
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Affiliation(s)
- Mohannad A. Almikhlafi
- Department of Pharmacology and Toxicology, College of Pharmacy, Taibah University, Madinah, Saudi Arabia
| | - Mohammed M. Karami
- Department of Physiology, Neuroscience Unit, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ankit Jana
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT) Deemed to be University, Campus-11, Patia, Bhubaneswar, Odisha, 751024, India
| | - Thamer M. Alqurashi
- Department of Pharmacology, Faculty of Medicine, Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohammed Majrashi
- Department of Pharmacology, Faculty of Medicine, University of Jeddah, Jeddah, Saudi Arabia
| | - Badrah S. Alghamdi
- Department of Physiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- The Neuroscience Research Unit, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ghulam Md. Ashraf
- Department of Medical Laboratory Sciences, College of Health Sciences, University of Sharjah, University City, Sharjah 27272, United Arab Emirates
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5
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Sulfur amino acid supplementation displays therapeutic potential in a C. elegans model of Duchenne muscular dystrophy. Commun Biol 2022; 5:1255. [PMID: 36385509 PMCID: PMC9668843 DOI: 10.1038/s42003-022-04212-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 11/01/2022] [Indexed: 11/17/2022] Open
Abstract
Mutations in the dystrophin gene cause Duchenne muscular dystrophy (DMD), a common muscle disease that manifests with muscle weakness, wasting, and degeneration. An emerging theme in DMD pathophysiology is an intramuscular deficit in the gasotransmitter hydrogen sulfide (H2S). Here we show that the C. elegans DMD model displays reduced levels of H2S and expression of genes required for sulfur metabolism. These reductions can be offset by increasing bioavailability of sulfur containing amino acids (L-methionine, L-homocysteine, L-cysteine, L-glutathione, and L-taurine), augmenting healthspan primarily via improved calcium regulation, mitochondrial structure and delayed muscle cell death. Additionally, we show distinct differences in preservation mechanisms between sulfur amino acid vs H2S administration, despite similarities in required health-preserving pathways. Our results suggest that the H2S deficit in DMD is likely caused by altered sulfur metabolism and that modulation of this pathway may improve DMD muscle health via multiple evolutionarily conserved mechanisms. A C. elegans model of Duchenne muscular dystrophy reveals a potential role for disrupted sulfur metabolism in the disease and thus the therapeutic potential of sulfur amino acid supplementation.
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6
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Fralish Z, Lotz EM, Chavez T, Khodabukus A, Bursac N. Neuromuscular Development and Disease: Learning From in vitro and in vivo Models. Front Cell Dev Biol 2021; 9:764732. [PMID: 34778273 PMCID: PMC8579029 DOI: 10.3389/fcell.2021.764732] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/06/2021] [Indexed: 01/02/2023] Open
Abstract
The neuromuscular junction (NMJ) is a specialized cholinergic synaptic interface between a motor neuron and a skeletal muscle fiber that translates presynaptic electrical impulses into motor function. NMJ formation and maintenance require tightly regulated signaling and cellular communication among motor neurons, myogenic cells, and Schwann cells. Neuromuscular diseases (NMDs) can result in loss of NMJ function and motor input leading to paralysis or even death. Although small animal models have been instrumental in advancing our understanding of the NMJ structure and function, the complexities of studying this multi-tissue system in vivo and poor clinical outcomes of candidate therapies developed in small animal models has driven the need for in vitro models of functional human NMJ to complement animal studies. In this review, we discuss prevailing models of NMDs and highlight the current progress and ongoing challenges in developing human iPSC-derived (hiPSC) 3D cell culture models of functional NMJs. We first review in vivo development of motor neurons, skeletal muscle, Schwann cells, and the NMJ alongside current methods for directing the differentiation of relevant cell types from hiPSCs. We further compare the efficacy of modeling NMDs in animals and human cell culture systems in the context of five NMDs: amyotrophic lateral sclerosis, myasthenia gravis, Duchenne muscular dystrophy, myotonic dystrophy, and Pompe disease. Finally, we discuss further work necessary for hiPSC-derived NMJ models to function as effective personalized NMD platforms.
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Affiliation(s)
- Zachary Fralish
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Ethan M Lotz
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Taylor Chavez
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Alastair Khodabukus
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Nenad Bursac
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
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miRNome profiling in Duchenne muscular dystrophy; identification of asymptomatic and manifesting female carriers. Biosci Rep 2021; 41:229711. [PMID: 34472584 PMCID: PMC8450315 DOI: 10.1042/bsr20211325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 11/17/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a fatal neuromuscular disorder that occurs due to inactivating mutations in DMD gene, leading to muscular dystrophy. Prediction of pathological complications of DMD and the identification of female carriers are important research points that aim to reduce disease burden. Herein, we describe a case of a late DMD patient and his immediate female family members, who all carry same DMD mutation and exhibited varied degrees of symptoms. In our study, we sequenced the whole miRNome in leukocytes and plasma of the family members and results were validated using real-time PCR. Our results highlighted the role of miR-409-3p, miR-424-5p, miR-144-3p as microRNAs that show correlation with the extent of severity of muscular weakness and can be used for detection of asymptomatic carriers. Cellular and circulating levels of miR-494-3p had shown significant increase in symptomatic carriers, which may indicate significant roles played by this miRNA in the onset of muscular weakness. Interestingly, circulating levels of miR-206 and miR-410-3p were significantly increased only in the severely symptomatic carrier. In conclusion, our study highlighted several miRNA species, which could be used in predicting the onset of muscle and/or neurological complications in DMD carriers.
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8
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Ebrahimi M, Lad H, Fusto A, Tiper Y, Datye A, Nguyen CT, Jacques E, Moyle LA, Nguyen T, Musgrave B, Chávez-Madero C, Bigot A, Chen C, Turner S, Stewart BA, Pegoraro E, Vitiello L, Gilbert PM. De novo revertant fiber formation and therapy testing in a 3D culture model of Duchenne muscular dystrophy skeletal muscle. Acta Biomater 2021; 132:227-244. [PMID: 34048976 DOI: 10.1016/j.actbio.2021.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 12/18/2022]
Abstract
The biological basis of Duchenne muscular dystrophy (DMD) pathology is only partially characterized and there are still few disease-modifying therapies available, therein underlying the value of strategies to model and study DMD. Dystrophin, the causative gene of DMD, is responsible for linking the cytoskeleton of muscle fibers to the extracellular matrix beyond the sarcolemma. We posited that disease-associated phenotypes not yet captured by two-dimensional culture methods would arise by generating multinucleated muscle cells within a three-dimensional (3D) extracellular matrix environment. Herein we report methods to produce 3D human skeletal muscle microtissues (hMMTs) using clonal, immortalized myoblast lines established from healthy and DMD donors. We also established protocols to evaluate immortalized hMMT self-organization and myotube maturation, as well as calcium handling, force generation, membrane stability (i.e., creatine kinase activity and Evans blue dye permeability) and contractile apparatus organization following electrical-stimulation. In examining hMMTs generated with a cell line wherein the dystrophin gene possessed a duplication of exon 2, we observed rare dystrophin-positive myotubes, which were not seen in 2D cultures. Further, we show that treating DMD hMMTs with a β1-integrin activating antibody, improves contractile apparatus maturation and stability. Hence, immortalized myoblast-derived DMD hMMTs offer a pre-clinical system with which to investigate the potential of duplicated exon skipping strategies and those that protect muscle cells from contraction-induced injury. STATEMENT OF SIGNIFICANCE: Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disorder that is caused by mutation of the dystrophin gene. The biological basis of DMD pathology is only partially characterized and there is no cure for this fatal disease. Here we report a method to produce 3D human skeletal muscle microtissues (hMMTs) using immortalized human DMD and healthy myoblasts. Morphological and functional assessment revealed DMD-associated pathophysiology including impaired calcium handling and de novo formation of dystrophin-positive revertant muscle cells in immortalized DMD hMMTs harbouring an exon 2 duplication, a feature of many DMD patients that has not been recapitulated in culture prior to this report. We further demonstrate that this "DMD in a dish" system can be used as a pre-clinical assay to test a putative DMD therapeutic and study the mechanism of action.
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Affiliation(s)
- Majid Ebrahimi
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Heta Lad
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Aurora Fusto
- Department of Neuroscience, University of Padua, Padua, 35128, Italy
| | - Yekaterina Tiper
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Asiman Datye
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Christine T Nguyen
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S3G5, Canada; Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L1C6, Canada
| | - Erik Jacques
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Louise A Moyle
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Thy Nguyen
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Brennen Musgrave
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Carolina Chávez-Madero
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada
| | - Anne Bigot
- Sorbonne Universite, INSERM, Association Institut de Myologie, Centre de Recherche en Myologie, Paris UMRS974, France
| | - Chun Chen
- Pliant Therapeutics, Inc, South San Francisco, California 94080, USA
| | - Scott Turner
- Pliant Therapeutics, Inc, South San Francisco, California 94080, USA
| | - Bryan A Stewart
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S3G5, Canada; Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L1C6, Canada
| | - Elena Pegoraro
- Department of Neuroscience, University of Padua, Padua, 35128, Italy
| | - Libero Vitiello
- Department of Biology, University of Padua, Padua 35131, Italy; Interuniversity Institute of Myology (IIM), Italy
| | - Penney M Gilbert
- Donnelly Centre, University of Toronto, Toronto, ON M5S3E1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S3G9, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S3G5, Canada.
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9
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Silvera S, Wilkinson JA, LeBlanc PJ. Characterization of neutral sphingomyelinase activity and isoform expression in rodent skeletal muscle mitochondria. Mitochondrion 2021; 59:184-189. [PMID: 34089907 DOI: 10.1016/j.mito.2021.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/04/2021] [Accepted: 06/01/2021] [Indexed: 12/01/2022]
Abstract
Skeletal muscle is composed of fiber types that differ in mitochondrial content, antioxidant capacity, and susceptibility to apoptosis. Ceramides have been linked to oxidative stress-mediated apoptotic intracellular signalling and the enzyme neutral sphingomyelinase (nSMase) is, in part, responsible for generating these ceramides through the hydrolysis of sphingomyelin. Despite the role of ceramides in mediating apoptosis, there is a gap in the literature regarding nSMase in skeletal muscle mitochondria. This study aimed to characterize total nSMase activity and individual isoform expression in isolated subsarcolemmal (SS) mitochondria from soleus, diaphragm, plantaris, and extensor digitorum longus (EDL). Total nSMase activity did not differ between muscle types. nSMase2 content was detectable in all muscles and higher in EDL, soleus, and plantaris compared to diaphragm whereas nSMase3 was undetectable in all muscles. Finally, total nSMase activity positively correlated to nSMase2 protein content in soleus but not the other muscles. These findings suggest that nSMase associated with SS mitochondria may play a role in intracellular signalling processes involving ceramides in skeletal muscle and nSMase2 may be the key isoform, specifically in slow twitch muscle like soleus. Further studies are needed to fully elucidate the specific contribution of nSMase, along with the role of the various isoforms and mitochondrial subpopulation in generating mitochondrial ceramides in skeletal muscle, and its potential effects on mediating apoptosis.
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Affiliation(s)
- Sebastian Silvera
- Center for Bone and Muscle Health, Faculty of Applied Health Science, Brock University, Canada
| | - Jennifer A Wilkinson
- Center for Bone and Muscle Health, Faculty of Applied Health Science, Brock University, Canada
| | - Paul J LeBlanc
- Center for Bone and Muscle Health, Faculty of Applied Health Science, Brock University, Canada.
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10
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Sagar S, Kapoor H, Chaudhary N, Roy SS. Cellular and mitochondrial calcium communication in obstructive lung disorders. Mitochondrion 2021; 58:184-199. [PMID: 33766748 DOI: 10.1016/j.mito.2021.03.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 03/03/2021] [Accepted: 03/15/2021] [Indexed: 12/14/2022]
Abstract
Calcium (Ca2+) signalling is well known to dictate cellular functioning and fate. In recent years, the accumulation of Ca2+ in the mitochondria has emerged as an important factor in Chronic Respiratory Diseases (CRD) such as Asthma and Chronic Obstructive Pulmonary Disease (COPD). Various reports underline an aberrant increase in the intracellular Ca2+, leading to mitochondrial ROS generation, and further activation of the apoptotic pathway in these diseases. Mitochondria contribute to Ca2+ buffering which in turn regulates mitochondrial metabolism and ATP production. Disruption of this Ca2+ balance leads to impaired cellular processes like apoptosis or necrosis and thus contributes to the pathophysiology of airway diseases. This review highlights the key role of cytoplasmic and mitochondrial Ca2+ signalling in regulating CRD, such as asthma and COPD. A better understanding of the dysregulation of mitochondrial Ca2+ homeostasis in these diseases could provide cues for the development of advanced therapeutic interventions in these diseases.
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Affiliation(s)
- Shakti Sagar
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Himanshi Kapoor
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India
| | - Nisha Chaudhary
- Multidisciplinary Center for Advanced Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Soumya Sinha Roy
- CSIR-Institute of Genomics & Integrative Biology, New Delhi, India; Academy of Scientific & Innovative Research (AcSIR), Ghaziabad 201002, India.
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Stocco A, Smolina N, Sabatelli P, Šileikytė J, Artusi E, Mouly V, Cohen M, Forte M, Schiavone M, Bernardi P. Treatment with a triazole inhibitor of the mitochondrial permeability transition pore fully corrects the pathology of sapje zebrafish lacking dystrophin. Pharmacol Res 2021; 165:105421. [PMID: 33429034 DOI: 10.1016/j.phrs.2021.105421] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 12/28/2022]
Abstract
High-throughput screening identified isoxazoles as potent but metabolically unstable inhibitors of the mitochondrial permeability transition pore (PTP). Here we have studied the effects of a metabolically stable triazole analog, TR001, which maintains the PTP inhibitory properties with an in vitro potency in the nanomolar range. We show that TR001 leads to recovery of muscle structure and function of sapje zebrafish, a severe model of Duchenne muscular dystrophy (DMD). PTP inhibition fully restores the otherwise defective respiration in vivo, allowing normal development of sapje individuals in spite of lack of dystrophin. About 80 % sapje zebrafish treated with TR001 are alive and normal at 18 days post fertilization (dpf), a point in time when not a single untreated sapje individual survives. Time to 50 % death of treated zebrafish increases from 5 to 28 dpf, a sizeable number of individuals becoming young adults in spite of the persistent lack of dystrophin expression. TR001 improves respiration of myoblasts and myotubes from DMD patients, suggesting that PTP-dependent dysfunction also occurs in the human disease and that mitochondrial therapy of DMD with PTP-inhibiting triazoles is a viable treatment option.
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Affiliation(s)
- Anna Stocco
- Department of Biomedical Sciences and CNR Neuroscience Institute, University of Padova, Padova, Italy
| | - Natalia Smolina
- Department of Biomedical Sciences and CNR Neuroscience Institute, University of Padova, Padova, Italy
| | - Patrizia Sabatelli
- CNR-Institute of Molecular Genetics "Luigi Luca Cavalli-Sforza"-Unit of Bologna, Bologna, Italy; IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Justina Šileikytė
- Vollum Institute and Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Edoardo Artusi
- Department of Biomedical Sciences and CNR Neuroscience Institute, University of Padova, Padova, Italy
| | - Vincent Mouly
- Center for Research in Myology UMRS 974, Sorbonne Université, INSERM, Myology Institute, Paris, France
| | - Michael Cohen
- Vollum Institute and Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Michael Forte
- Vollum Institute and Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Marco Schiavone
- Department of Biomedical Sciences and CNR Neuroscience Institute, University of Padova, Padova, Italy.
| | - Paolo Bernardi
- Department of Biomedical Sciences and CNR Neuroscience Institute, University of Padova, Padova, Italy.
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Kourakis S, Timpani CA, de Haan JB, Gueven N, Fischer D, Rybalka E. Targeting Nrf2 for the treatment of Duchenne Muscular Dystrophy. Redox Biol 2021; 38:101803. [PMID: 33246292 PMCID: PMC7695875 DOI: 10.1016/j.redox.2020.101803] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 11/02/2020] [Accepted: 11/15/2020] [Indexed: 12/15/2022] Open
Abstract
Imbalances in redox homeostasis can result in oxidative stress, which is implicated in various pathological conditions including the fatal neuromuscular disease Duchenne Muscular Dystrophy (DMD). DMD is a complicated disease, with many druggable targets at the cellular and molecular level including calcium-mediated muscle degeneration; mitochondrial dysfunction; oxidative stress; inflammation; insufficient muscle regeneration and dysregulated protein and organelle maintenance. Previous investigative therapeutics tended to isolate and focus on just one of these targets and, consequently, therapeutic activity has been limited. Nuclear erythroid 2-related factor 2 (Nrf2) is a transcription factor that upregulates many cytoprotective gene products in response to oxidants and other toxic stressors. Unlike other strategies, targeted Nrf2 activation has the potential to simultaneously modulate separate pathological features of DMD to amplify therapeutic benefits. Here, we review the literature providing theoretical context for targeting Nrf2 as a disease modifying treatment against DMD.
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Affiliation(s)
- Stephanie Kourakis
- College of Health and Biomedicine, Victoria University, Melbourne, Victoria, Australia.
| | - Cara A Timpani
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia; Australian Institute for Musculoskeletal Science, Victoria University, St Albans, Victoria, Australia.
| | - Judy B de Haan
- Oxidative Stress Laboratory, Basic Science Domain, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia; Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Australia.
| | - Nuri Gueven
- School of Pharmacy and Pharmacology, University of Tasmania, Hobart, Tasmania, Australia.
| | - Dirk Fischer
- Division of Developmental- and Neuropediatrics, University Children's Hospital Basel (UKBB), University of Basel, Basel, Switzerland.
| | - Emma Rybalka
- College of Health and Biomedicine, Victoria University, Melbourne, Victoria, Australia; Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia; Australian Institute for Musculoskeletal Science, Victoria University, St Albans, Victoria, Australia.
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13
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Physical exertion exacerbates decline in the musculature of an animal model of Duchenne muscular dystrophy. Proc Natl Acad Sci U S A 2019; 116:3508-3517. [PMID: 30755520 DOI: 10.1073/pnas.1811379116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a genetic disorder caused by loss of the protein dystrophin. In humans, DMD has early onset, causes developmental delays, muscle necrosis, loss of ambulation, and death. Current animal models have been challenged by their inability to model the early onset and severity of the disease. It remains unresolved whether increased sarcoplasmic calcium observed in dystrophic muscles follows or leads the mechanical insults caused by the muscle's disrupted contractile machinery. This knowledge has important implications for patients, as potential physiotherapeutic treatments may either help or exacerbate symptoms, depending on how dystrophic muscles differ from healthy ones. Recently we showed how burrowing dystrophic (dys-1) C. elegans recapitulate many salient phenotypes of DMD, including loss of mobility and muscle necrosis. Here, we report that dys-1 worms display early pathogenesis, including dysregulated sarcoplasmic calcium and increased lethality. Sarcoplasmic calcium dysregulation in dys-1 worms precedes overt structural phenotypes (e.g., mitochondrial, and contractile machinery damage) and can be mitigated by reducing calmodulin expression. To learn how dystrophic musculature responds to altered physical activity, we cultivated dys-1 animals in environments requiring high intensity or high frequency of muscle exertion during locomotion. We find that several muscular parameters (e.g., size) improve with increased activity. However, longevity in dystrophic animals was negatively associated with muscular exertion, regardless of effort duration. The high degree of phenotypic conservation between dystrophic worms and humans provides a unique opportunity to gain insight into the pathology of the disease as well as the initial assessment of potential treatment strategies.
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Romero-Garcia S, Prado-Garcia H. Mitochondrial calcium: Transport and modulation of cellular processes in homeostasis and cancer (Review). Int J Oncol 2019; 54:1155-1167. [PMID: 30720054 DOI: 10.3892/ijo.2019.4696] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 12/06/2018] [Indexed: 11/05/2022] Open
Abstract
In addition to their role in providing cellular energy, mitochondria fulfill a key function in cellular calcium management. The present review provides an integrative view of cellular and mitochondrial calcium homeostasis, and discusses how calcium regulates mitochondrial dynamics and functionality, thus affecting various cellular processes. Calcium crosstalk exists in the domain created between the endoplasmic reticulum and mitochondria, which is known as the mitochondria‑associated membrane (MAM), and controls cellular homeostasis. Calcium signaling participates in numerous biochemical and cellular processes, where calcium concentration, temporality and durability are part of a regulated, finely tuned interplay in non‑transformed cells. In addition, cancer cells modify their MAMs, which consequently affects calcium homeostasis to support mesenchymal transformation, migration, invasiveness, metastasis and autophagy. Alterations in calcium homeostasis may also support resistance to apoptosis, which is a serious problem facing current chemotherapeutic treatments. Notably, mitochondrial dynamics are also affected by mitochondrial calcium concentration to promote cancer survival responses. Dysregulated levels of mitochondrial calcium, alongside other signals, promote mitoflash generation in tumor cells, and an increased frequency of mitoflashes may induce epithelial‑to‑mesenchymal transition. Therefore, cancer cells remodel their calcium balance through numerous mechanisms that support their survival and growth.
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Affiliation(s)
- Susana Romero-Garcia
- Department of Chronic-Degenerative Diseases, National Institute of Respiratory Diseases 'Ismael Cosío Villegas', CP 14080 Mexico City, Mexico
| | - Heriberto Prado-Garcia
- Department of Chronic-Degenerative Diseases, National Institute of Respiratory Diseases 'Ismael Cosío Villegas', CP 14080 Mexico City, Mexico
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15
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Ramalho TC, de Castro AA, Tavares TS, Silva MC, Silva DR, Cesar PH, Santos LA, da Cunha EFF, Nepovimova E, Kuca K. Insights into the pharmaceuticals and mechanisms of neurological orphan diseases: Current Status and future expectations. Prog Neurobiol 2018; 169:135-157. [PMID: 29981392 DOI: 10.1016/j.pneurobio.2018.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 06/30/2018] [Indexed: 12/20/2022]
Abstract
Several rare or orphan diseases have been characterized that singly affect low numbers of people, but cumulatively reach ∼6%-10% of the population in Europe and in the United States. Human genetics has shown to be broadly effective when evaluating subjacent genetic defects such as orphan genetic diseases, but on the other hand, a modest progress has been achieved toward comprehending the molecular pathologies and designing new therapies. Chemical genetics, placed at the interface of chemistry and genetics, could be employed to understand the molecular mechanisms of subjacent illnesses and for the discovery of new remediation processes. This review debates current progress in chemical genetics, and how a variety of compounds and reaction mechanisms can be used to study and ultimately treat rare genetic diseases. We focus here on a study involving Amyotrophic lateral sclerosis (ALS), Duchenne Muscular Dystrophy (DMD), Spinal muscular atrophy (SMA) and Familial Amyloid Polyneuropathy (FAP), approaching different treatment methods and the reaction mechanisms of several compounds, trying to elucidate new routes capable of assisting in the treatment profile.
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Affiliation(s)
- Teodorico C Ramalho
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil; Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Hradec Kralove, Czech Republic.
| | | | - Tássia S Tavares
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Maria C Silva
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Daniela R Silva
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Pedro H Cesar
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Lucas A Santos
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Elaine F F da Cunha
- Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, Brazil
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic.
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Schiavone M, Zulian A, Menazza S, Petronilli V, Argenton F, Merlini L, Sabatelli P, Bernardi P. Alisporivir rescues defective mitochondrial respiration in Duchenne muscular dystrophy. Pharmacol Res 2017; 125:122-131. [DOI: 10.1016/j.phrs.2017.09.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 09/05/2017] [Accepted: 09/05/2017] [Indexed: 01/09/2023]
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17
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Pauly M, Angebault-Prouteau C, Dridi H, Notarnicola C, Scheuermann V, Lacampagne A, Matecki S, Fauconnier J. ER stress disturbs SR/ER-mitochondria Ca 2+ transfer: Implications in Duchenne muscular dystrophy. Biochim Biophys Acta Mol Basis Dis 2017. [PMID: 28625916 DOI: 10.1016/j.bbadis.2017.06.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Besides its role in calcium (Ca2+) homeostasis, the sarco-endoplamic reticulum (SR/ER) controls protein folding and is tethered to mitochondria. Under pathophysiological conditions the unfolded protein response (UPR) is associated with disturbance in SR/ER-mitochondria crosstalk. Here, we investigated whether ER stress altered SR/ER-mitochondria links, Ca2+ handling and muscle damage in WT (Wild Type) and mdx mice, the murine model of Duchenne Muscular Dystrophy (DMD). In WT mice, the SR/ER-mitochondria links were decreased in isolated FDB muscle fibers after injection of ER stress activator tunicamycin (TM). Ca2+ imaging revealed an increase of cytosolic Ca2+ transient and a decrease of mitochondrial Ca2+ uptake. The force generating capacity of muscle dropped after TM. This impaired contractile function was accompanied by an increase in autophagy markers and calpain-1 activation. Conversely, ER stress inhibitors restored SR/ER-mitochondria links, mitochondrial Ca2+ uptake and improved diaphragm contractility in mdx mice. Our findings demonstrated that ER stress-altered SR/ER-mitochondria links, disturbed Ca2+ handling and muscle function in WT and mdx mice. Thus, ER stress may open up a prospect of new therapeutic targets in DMD.
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Affiliation(s)
- Marion Pauly
- Inserm U1055, Hypoxie et Physiopathologies, Université Grenoble Alpes, Grenoble, France; Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | | | - Haikel Dridi
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | - Cécile Notarnicola
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | - Valérie Scheuermann
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | - Alain Lacampagne
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | - Stefan Matecki
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France
| | - Jérémy Fauconnier
- Inserm U1046, UMR CNRS 9214, Université Montpellier, CHRU Montpellier, Montpellier, France.
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18
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Saüc S, Frieden M. Neurological and Motor Disorders: TRPC in the Skeletal Muscle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:557-575. [PMID: 28900933 DOI: 10.1007/978-3-319-57732-6_28] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transient receptor potential canonical (TRPC) channels belong to the large family of TRPs that are mostly nonselective cation channels with a great variety of gating mechanisms. TRPC are composed of seven members that can all be activated downstream of agonist-induced phospholipase C stimulation, but some members are also stretch-activated and/or are part of the store-operated Ca2+ entry (SOCE) pathway. Skeletal muscles generate contraction via an explosive increase of cytosolic Ca2+ concentration resulting almost exclusively from sarcoplasmic reticulum Ca2+ channel opening. Even if neglected for a long time, it is now commonly accepted that Ca2+ entry via SOCE and other routes is essential to sustain contractions of the skeletal muscle. In addition, Ca2+ influx is required during muscle regeneration, and alteration of the influx is associated with myopathies. In this chapter, we review the implication of TRPC channels at different stages of muscle regeneration, in adult muscle fibers, and discuss their implication in myopathies.
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Affiliation(s)
- Sophie Saüc
- Department of Cell Physiology and Metabolism, University of Geneva, 1 rue Michel Servet, 1211, Geneva, Switzerland
| | - Maud Frieden
- Department of Cell Physiology and Metabolism, University of Geneva, 1 rue Michel Servet, 1211, Geneva, Switzerland.
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19
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Farini A, Sitzia C, Cassinelli L, Colleoni F, Parolini D, Giovanella U, Maciotta S, Colombo A, Meregalli M, Torrente Y. Inositol 1,4,5-trisphosphate (IP3)-dependent Ca2+ signaling mediates delayed myogenesis in Duchenne muscular dystrophy fetal muscle. Development 2016; 143:658-69. [DOI: 10.1242/dev.126193] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disorder characterized by muscle wasting and premature death. The defective gene is dystrophin, a structural protein, absence of which causes membrane fragility and myofiber necrosis. Several lines of evidence showed that in adult DMD patients dystrophin is involved in signaling pathways that regulate calcium homeostasis and differentiation programs. However, secondary aspects of the disease, such as inflammation and fibrosis development, might represent a bias in the analysis. Because fetal muscle is not influenced by gravity and does not suffer from mechanical load and/or inflammation, we investigated 12-week-old fetal DMD skeletal muscles, highlighting for the first time early alterations in signaling pathways mediated by the absence of dystrophin itself. We found that PLC/IP3/IP3R/Ryr1/Ca2+ signaling is widely active in fetal DMD skeletal muscles and, through the calcium-dependent PKCα protein, exerts a fundamental regulatory role in delaying myogenesis and in myofiber commitment. These data provide new insights into the origin of DMD pathology during muscle development.
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Affiliation(s)
- Andrea Farini
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Clementina Sitzia
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Letizia Cassinelli
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Federica Colleoni
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Daniele Parolini
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Umberto Giovanella
- Consiglio Nazionale delle Ricerche, Istituto per lo Studio delle Macromolecole (CNR-ISMAC), via Bassini 15, Milano 20133, Italy
| | - Simona Maciotta
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Augusto Colombo
- Servizio ‘Legge 194’ Dipartimento BDN-Fondazione IRCCS, Policlinico Mangiagalli-Regina Elena, Via Francesco Sforza 35, Milan 20122, Italy
| | - Mirella Meregalli
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
| | - Yvan Torrente
- Laboratorio di Cellule Staminali, Dipartimento di Fisiopatologia medico-chirurgica e dei Trapianti, Università degli Studi di Milano, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Centro Dino Ferrari, Via Francesco Sforza 35, Milan 20122, Centro Dino Ferrari, Italy
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Rybalka E, Timpani CA, Stathis CG, Hayes A, Cooke MB. Metabogenic and Nutriceutical Approaches to Address Energy Dysregulation and Skeletal Muscle Wasting in Duchenne Muscular Dystrophy. Nutrients 2015; 7:9734-67. [PMID: 26703720 PMCID: PMC4690050 DOI: 10.3390/nu7125498] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 10/29/2015] [Accepted: 11/13/2015] [Indexed: 12/21/2022] Open
Abstract
Duchenne Muscular Dystrophy (DMD) is a fatal genetic muscle wasting disease with no current cure. A prominent, yet poorly treated feature of dystrophic muscle is the dysregulation of energy homeostasis which may be associated with intrinsic defects in key energy systems and promote muscle wasting. As such, supplementative nutriceuticals that target and augment the bioenergetical expansion of the metabolic pathways involved in cellular energy production have been widely investigated for their therapeutic efficacy in the treatment of DMD. We describe the metabolic nuances of dystrophin-deficient skeletal muscle and review the potential of various metabogenic and nutriceutical compounds to ameliorate the pathological and clinical progression of the disease.
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Affiliation(s)
- Emma Rybalka
- Centre for Chronic Disease, College of Health & Biomedicine, Victoria University, Melbourne 8001, Australia.
- Institute of Sport, Exercise & Healthy Living, Victoria University, Melbourne 8001, Australia.
- Australian Institute of Musculoskeletal Science, Western Health, Melbourne 3021, Australia.
| | - Cara A Timpani
- Centre for Chronic Disease, College of Health & Biomedicine, Victoria University, Melbourne 8001, Australia.
- Institute of Sport, Exercise & Healthy Living, Victoria University, Melbourne 8001, Australia.
| | - Christos G Stathis
- Centre for Chronic Disease, College of Health & Biomedicine, Victoria University, Melbourne 8001, Australia.
- Institute of Sport, Exercise & Healthy Living, Victoria University, Melbourne 8001, Australia.
- Australian Institute of Musculoskeletal Science, Western Health, Melbourne 3021, Australia.
| | - Alan Hayes
- Centre for Chronic Disease, College of Health & Biomedicine, Victoria University, Melbourne 8001, Australia.
- Institute of Sport, Exercise & Healthy Living, Victoria University, Melbourne 8001, Australia.
- Australian Institute of Musculoskeletal Science, Western Health, Melbourne 3021, Australia.
| | - Matthew B Cooke
- Centre for Chronic Disease, College of Health & Biomedicine, Victoria University, Melbourne 8001, Australia.
- Institute of Sport, Exercise & Healthy Living, Victoria University, Melbourne 8001, Australia.
- Australian Institute of Musculoskeletal Science, Western Health, Melbourne 3021, Australia.
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21
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Dystrophin induced cognitive impairment: mechanisms, models and therapeutic strategies. Ann Neurosci 2015; 22:108-18. [PMID: 26130916 PMCID: PMC4480258 DOI: 10.5214/ans.0972.7531.221210] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 01/19/2015] [Accepted: 03/05/2015] [Indexed: 12/13/2022] Open
Abstract
Existence of conserved domains in dystrophin and its associated complexes provide an opportunity to understand the role of dystrophin associated signalling and its association with neuronal metabolism in a variety of model organisms. We critically reviewed the studies till 2013 through established search engines and databases. Thus, we review the role of dystrophin and its isoforms in different animal models at developmental stages in the neuronal metabolism to enhance the therapeutic strategies. Dystrophin interacts with other proteins in such a way that, when affected, it results in co-morbidities including autism and other neuropsychiatric disorders. It is speculated that various signalling molecules may converge to disrupt neuronal metabolism not adequately studied. TGF-β, RhoGAP and CAM mediated signalling molecules are the chief cause of mortalities due to respiratory and cardiac involvement but remain underevaluated targets for cognitive impairment in DMD/BMD. Manipulation of these signalling pathways could be potent intervention in dystrophin induced cognitive impairment while complementary therapeutic approaches may also be helpful in the treatment of cognitive impairment associated with DMD/BMD.
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22
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Schöneich C, Dremina E, Galeva N, Sharov V. Apoptosis in differentiating C2C12 muscle cells selectively targets Bcl-2-deficient myotubes. Apoptosis 2014; 19:42-57. [PMID: 24129924 DOI: 10.1007/s10495-013-0922-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Muscle cell apoptosis accompanies normal muscle development and regeneration, as well as degenerative diseases and aging. C2C12 murine myoblast cells represent a common model to study muscle differentiation. Though it was already shown that myogenic differentiation of C2C12 cells is accompanied by enhanced apoptosis in a fraction of cells, either the cell population sensitive to apoptosis or regulatory mechanisms for the apoptotic response are unclear so far. In the current study we characterize apoptotic phenotypes of different types of C2C12 cells at all stages of differentiation, and report here that myotubes of differentiated C2C12 cells with low levels of anti-apoptotic Bcl-2 expression are particularly vulnerable to apoptosis even though they are displaying low levels of pro-apoptotic proteins Bax, Bak and Bad. In contrast, reserve cells exhibit higher levels of Bcl-2 and high resistance to apoptosis. The transfection of proliferating myoblasts with Bcl-2 prior to differentiation did not protect against spontaneous apoptosis accompanying differentiation of C2C12 cells but led to Bcl-2 overexpression in myotubes and to significant protection from apoptotic cell loss caused by exposure to hydrogen peroxide. Overall, our data advocate for a Bcl-2-dependent mechanism of apoptosis in differentiated muscle cells. However, downstream processes for spontaneous and hydrogen peroxide induced apoptosis are not completely similar. Apoptosis in differentiating myoblasts and myotubes is regulated not through interaction of Bcl-2 with pro-apoptotic Bcl-2 family proteins such as Bax, Bak, and Bad.
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23
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Fujak A, Haaker G, Funk J. [Current care strategies for Duchenne muscular dystrophy]. DER ORTHOPADE 2014; 43:636-42. [PMID: 24906240 DOI: 10.1007/s00132-013-2217-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND The medical care of patients with Duchenne muscular dystrophy (DMD) is an interdisciplinary and multifaceted task. The vast majority of those affected show a nearly constant course which is reflected in a corresponding stage-oriented treatment concept. Although there is still no causal therapy available for DMD, the course and in particular the quality of life of patients can be decisively improved by established medical practices. THERAPEUTIC STRATEGIES The orthopedic problems of DMD patients include contractures of the upper and lower extremities as well as sitting instability due to progressive scoliosis with pelvic imbalance. The orthopedic treatment incorporates conservative measures, such as physiotherapy, provision of orthotic devices and wheelchairs as well as surgery to resolve contractures of the lower extremities and surgical stabilization of the spine. Furthermore, in these patients orthopedic surgeons and trauma surgeons are confronted with the treatment and prophylaxis of fractures induced by osteoporosis. An early onset of glucocorticoid therapy markedly delays the loss of motor abilities. TREATMENT ASPECTS An important aspect in the care of DMD patients is the timely prophylaxis and treatment of respiratory insufficiency with regular sessions of breathing therapy, learning breathing and coughing techniques and the sufficiently early start of non-invasive mechanically assisted ventilation. Of similar relevance are also the early recognition and cardioprotective treatment of cardiomyopathy. CONCLUSION The orthopedic surgeon accompanies the patient and family through all stages of the disease and must be appropriately informed on current management and treatment strategies even outside the limits of the personal field of specialization.
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Affiliation(s)
- A Fujak
- Orthopädische Klinik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Rathsberger Str. 57, 91054, Erlangen, Deutschland,
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24
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Hollinger K, Selsby JT. The physiological response of protease inhibition in dystrophic muscle. Acta Physiol (Oxf) 2013; 208:234-44. [PMID: 23648220 DOI: 10.1111/apha.12114] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Revised: 03/25/2013] [Accepted: 04/29/2013] [Indexed: 01/06/2023]
Abstract
Duchenne muscular dystrophy (DMD) is caused by the production of a non-functional dystrophin gene product and a failure to accumulate functional dystrophin protein in muscle cells. This leads to membrane instability, loss of Ca(2+) homoeostasis and widespread cellular injury. Associated with these changes are increased protease activities in a variety of proteolytic systems. As such, there have been numerous investigations directed towards determining the therapeutic potential of protease inhibition. In this review, evidence from genetic and/or pharmacological inhibition of proteases as a treatment strategy for DMD is systematically evaluated. Specifically, we review the potential roles of calpain, proteasome, caspase, matrix metalloproteinase and serine protease inhibition as therapeutic approaches for DMD. We conclude that despite early results to the contrary, inhibition of calpain proteases is unlikely to be successful. Conversely, evidence suggests that inhibition of proteasome, matrix metalloproteinases and serine proteases does appear to decrease disease severity. An important caveat to these conclusions, however, is that the fundamental cause of DMD, dystrophin deficiency, is not corrected by this strategy. Hence, this should not be viewed as a cure, but rather, protease inhibitors should be considered for inclusion in a therapeutic cocktail. Physiological Relevance. Selective modulation of protease activity has the potential to profoundly change intracellular physiology resulting in a possible treatment for DMD. However, alteration of protease activities could also lead to worsening of disease progression by promoting the accumulation of substrates in the cell. The balance of benefit and potential damage caused by protease inhibition in human DMD patients is largely unexplored.
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Affiliation(s)
- K. Hollinger
- Department of Animal Science; Iowa State University; Ames; IA; USA
| | - J. T. Selsby
- Department of Animal Science; Iowa State University; Ames; IA; USA
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25
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Harisseh R, Chatelier A, Magaud C, Déliot N, Constantin B. Involvement of TRPV2 and SOCE in calcium influx disorder in DMD primary human myotubes with a specific contribution of α1-syntrophin and PLC/PKC in SOCE regulation. Am J Physiol Cell Physiol 2013; 304:C881-94. [DOI: 10.1152/ajpcell.00182.2012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Calcium homeostasis is critical for several vital functions in excitable and nonexcitable cells and has been shown to be impaired in many pathologies including Duchenne muscular dystrophy (DMD). Various studies using murine models showed the implication of calcium entry in the dystrophic phenotype. However, alteration of store-operated calcium entry (SOCE) and transient receptor potential vanilloid 2 (TRPV2)-dependant cation entry has not been investigated yet in human skeletal muscle cells. We pharmacologically characterized basal and store-operated cation entries in primary cultures of myotubes prepared from muscle of normal and DMD patients and found, for the first time, an increased SOCE in DMD myotubes. Moreover, this increase cannot be explained by an over expression of the well-known SOCE actors: TRPC1/4, Orai1, and stromal interaction molecule 1 (STIM1) mRNA and proteins. Thus we investigated the modes of regulation of this cation entry. We firstly demonstrated the important role of the scaffolding protein α1-syntrophin, which regulates SOCE in primary human myotubes through its PDZ domain. We also studied the implication of phospholipase C (PLC) and protein kinase C (PKC) in SOCE and showed that their inhibition restores normal levels of SOCE in DMD human myotubes. In addition, the involvement of TRPV2 in calcium deregulation in DMD human myotubes was explored. We showed an abnormal elevation of TRPV2-dependant cation entry in dystrophic primary human myotubes compared with normal ones. These findings show that calcium homeostasis mishandling in DMD myotubes depends on SOCE under the influence of Ca2+/PLC/PKC pathway and α1-syntrophin regulation as well as on TRPV2-dependant cation influx.
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Affiliation(s)
- Rania Harisseh
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers/Centre National de la Recherche Scientifique FRE-3511 Poitiers, France
| | - Aurélien Chatelier
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers/Centre National de la Recherche Scientifique FRE-3511 Poitiers, France
| | - Christophe Magaud
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers/Centre National de la Recherche Scientifique FRE-3511 Poitiers, France
| | - Nadine Déliot
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers/Centre National de la Recherche Scientifique FRE-3511 Poitiers, France
| | - Bruno Constantin
- Institut de Physiologie et Biologie Cellulaires, Université de Poitiers/Centre National de la Recherche Scientifique FRE-3511 Poitiers, France
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Dystrophin/α1-syntrophin scaffold regulated PLC/PKC-dependent store-operated calcium entry in myotubes. Cell Calcium 2012; 52:445-56. [DOI: 10.1016/j.ceca.2012.08.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 07/16/2012] [Accepted: 08/06/2012] [Indexed: 11/17/2022]
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Le Borgne F, Guyot S, Logerot M, Beney L, Gervais P, Demarquoy J. Exploration of lipid metabolism in relation with plasma membrane properties of Duchenne muscular dystrophy cells: influence of L-carnitine. PLoS One 2012; 7:e49346. [PMID: 23209572 PMCID: PMC3507830 DOI: 10.1371/journal.pone.0049346] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 10/10/2012] [Indexed: 01/04/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) arises as a consequence of mutations in the dystrophin gene. Dystrophin is a membrane-spanning protein that connects the cytoskeleton and the basal lamina. The most distinctive features of DMD are a progressive muscular dystrophy, a myofiber degeneration with fibrosis and metabolic alterations such as fatty infiltration, however, little is known on lipid metabolism changes arising in Duchenne patient cells. Our goal was to identify metabolic changes occurring in Duchenne patient cells especially in terms of L-carnitine homeostasis, fatty acid metabolism both at the mitochondrial and peroxisomal level and the consequences on the membrane structure and function. In this paper, we compared the structural and functional characteristics of DMD patient and control cells. Using radiolabeled L-carnitine, we found, in patient muscle cells, a marked decrease in the uptake and the intracellular level of L-carnitine. Associated with this change, a decrease in the mitochondrial metabolism can be seen from the analysis of mRNA encoding for mitochondrial proteins. Probably, associated with these changes in fatty acid metabolism, alterations in the lipid composition of the cells were identified: with an increase in poly unsaturated fatty acids and a decrease in medium chain fatty acids, mono unsaturated fatty acids and in cholesterol contents. Functionally, the membrane of cells lacking dystrophin appeared to be less fluid, as determined at 37°C by fluorescence anisotropy. These changes may, at least in part, be responsible for changes in the phospholipids and cholesterol profile in cell membranes and ultimately may reduce the fluidity of the membrane. A supplementation with L-carnitine partly restored the fatty acid profile by increasing saturated fatty acid content and decreasing the amounts of MUFA, PUFA, VLCFA. L-carnitine supplementation also restored muscle membrane fluidity. This suggests that regulating lipid metabolism in DMD cells may improve the function of cells lacking dystrophin.
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Affiliation(s)
- Françoise Le Borgne
- Laboratoire Bio-PeroxIL, Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique, Université de Bourgogne - Faculté des Sciences Gabriel, Dijon, France
| | - Stéphane Guyot
- UMR A 02.102 Procédés Alimentaires et Microbiologiques, Equipe Procédés Microbiologiques et Biotechnologiques, AgroSup Dijon/Université de Bourgogne, bât Erasme, Dijon, France
| | - Morgan Logerot
- Laboratoire Bio-PeroxIL, Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique, Université de Bourgogne - Faculté des Sciences Gabriel, Dijon, France
| | - Laurent Beney
- UMR A 02.102 Procédés Alimentaires et Microbiologiques, Equipe Procédés Microbiologiques et Biotechnologiques, AgroSup Dijon/Université de Bourgogne, bât Erasme, Dijon, France
| | - Patrick Gervais
- UMR A 02.102 Procédés Alimentaires et Microbiologiques, Equipe Procédés Microbiologiques et Biotechnologiques, AgroSup Dijon/Université de Bourgogne, bât Erasme, Dijon, France
| | - Jean Demarquoy
- Laboratoire Bio-PeroxIL, Biochimie du Peroxysome, Inflammation et Métabolisme Lipidique, Université de Bourgogne - Faculté des Sciences Gabriel, Dijon, France
- * E-mail:
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Morgenroth VH, Hache LP, Clemens PR. Insights into bone health in Duchenne muscular dystrophy. BONEKEY REPORTS 2012; 1:9. [PMID: 23951421 DOI: 10.1038/bonekey.2012.5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Accepted: 11/05/2011] [Indexed: 12/22/2022]
Abstract
Poor bone health is a significant problem for patients with Duchenne muscular dystrophy (DMD), a progressive, disabling disease. Although the primary focus of DMD disease pathogenesis is degeneration of striated muscle, impairment of bone health likely has a role in the disease that has only been superficially examined to date. Deficiency of bone mineral density and increased incidence of bone fractures are well-recognized clinical components of the DMD phenotype. Furthermore, therapy with corticosteroids, an approved treatment for DMD that prolongs ambulation, may have multiple effects on bone health in DMD patients. This review examines the evidence in preclinical models and in human DMD disease that provides insight into the role performed by bone in the disease pathogenesis and phenotype of DMD. The information reviewed here points toward the need for mechanistic and therapeutic studies to optimize bone health in DMD patients.
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Chen F, Cao J, Liu Q, Qin J, Kong J, Wang Y, Li Y, Geng J, Li Q, Yang L, Xiang AP, Zhang C. Comparative study of myocytes from normal and mdx mice iPS cells. J Cell Biochem 2012; 113:678-84. [DOI: 10.1002/jcb.23397] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Rodríguez J, Navallas J, Gila L, Rodríguez I, Malanda A. The peak-to-peak ratio of single-fibre potentials is little influenced by changes in the electrode positions close to the muscle fibre. J Electromyogr Kinesiol 2010; 21:423-32. [PMID: 20451410 DOI: 10.1016/j.jelekin.2010.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 04/06/2010] [Accepted: 04/06/2010] [Indexed: 11/29/2022] Open
Abstract
In a series of previous works we studied the ratio between the amplitudes of the second and first phases (the peak-to-peak ratio) of single fibre action potential (SFAPs) using the Dimitrov-Dimitrova SFAP convolutional model as a reference. From experimental potentials extracted from both healthy and diseased muscles, we determined typical peak-to-peak ratio (PPR) values and ranges for both normal and pathological conditions. In addition, we investigated the changes observed in the PPR of consecutive potentials recorded at different fibre-to-electrode distances. However, our results were not conclusive due to insufficient data. The objective of the present work was to obtain a more concrete description of the relation between PPR and radial distance. To this end, we recorded 135 sets of consecutive SFAPs from the m. tibialis anterior of four normal subjects. The needle was intentionally moved whilst recording each SFAP set. We found that PPR was largely independent of small changes in electrode position when the electrode was close to the fibre and sufficiently far from the neuromuscular and/or fibre-tendon junctions. In the discussion, we provide evidence that this result is in agreement with the generation of extracellular potentials considering the spatial extension of the intracellular action potential (IAP) along the fibre.
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Affiliation(s)
- Javier Rodríguez
- Public University of Navarra, Department of Electrical and Electronic Engineering, 31006 Pamplona, Spain.
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Cárdenas C, Juretić N, Bevilacqua JA, García IE, Figueroa R, Hartley R, Taratuto AL, Gejman R, Riveros N, Molgó J, Jaimovich E. Abnormal distribution of inositol 1,4,5‐trisphosphate receptors in human muscle can be related to altered calcium signals and gene expression in Duchenne dystrophy‐derived cells. FASEB J 2010; 24:3210-21. [DOI: 10.1096/fj.09-152017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- César Cárdenas
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Department of PhysiologyUniversity of Pennsylvania Philadelphia Pennsylvania USA
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Nevenka Juretić
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Jorge A. Bevilacqua
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Programa de Anatomía y Biología del DesarrolloInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Departamento de Neurología y NeurocirugíaHospital Clínico Universidad de Chile Independencia Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Isaac E. García
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Reinaldo Figueroa
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Ricardo Hartley
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Ana L. Taratuto
- Departamento de NeuropatologíaInstituto de Investigaciones NeurológicasFLENI Buenos Aires Argentina
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Roger Gejman
- Departamento de Anatomía PatológicaFacultad de MedicinaPontificia Universidad Católica de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Nora Riveros
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Jordi Molgó
- Department of PhysiologyUniversity of Pennsylvania Philadelphia Pennsylvania USA
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
| | - Enrique Jaimovich
- Centro de Estudios Moleculares de la CélulaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile Santiago Chile
- Centre National de la Recherche ScientifiqueInstitut de Neurobiologie Alfred FessardFRC2118Laboratoire de Neurobiologie Cellulaire et Moléculaire UPR9040 Gif sur Yvette France
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Rodríguez J, Navallas J, Gila L, Rodríguez I, Malanda A. Relationship between the rise-time of single-fibre action potentials and radial distance in human muscle fibres. Clin Neurophysiol 2010; 121:214-20. [DOI: 10.1016/j.clinph.2009.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 10/02/2009] [Accepted: 10/15/2009] [Indexed: 10/20/2022]
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Itagaki K, Menconi M, Antoniu B, Zhang Q, Gonnella P, Soybel D, Hauser C, Hasselgren PO. Dexamethasone stimulates store-operated calcium entry and protein degradation in cultured L6 myotubes through a phospholipase A(2)-dependent mechanism. Am J Physiol Cell Physiol 2010; 298:C1127-39. [PMID: 20107037 DOI: 10.1152/ajpcell.00309.2009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Muscle wasting in various catabolic conditions is at least in part regulated by glucocorticoids. Increased calcium levels have been reported in atrophying muscle. Mechanisms regulating calcium homeostasis in muscle wasting, in particular the role of glucocorticoids, are poorly understood. Here we tested the hypothesis that glucocorticoids increase intracellular calcium concentrations in skeletal muscle and stimulate store-operated calcium entry (SOCE) and that these effects of glucocorticoids may at least in part be responsible for glucocorticoid-induced protein degradation. Treatment of cultured myotubes with dexamethasone, a frequently used in vitro model of muscle wasting, resulted in increased intracellular calcium concentrations determined by fura-2 AM fluorescence measurements. When SOCE was measured by using calcium "add-back" to muscle cells after depletion of intracellular calcium stores, results showed that SOCE was increased 15-25% by dexamethasone and that this response to dexamethasone was inhibited by the store-operated calcium channel blocker BTP2. Dexamethasone treatment stimulated the activity of calcium-independent phospholipase A(2) (iPLA(2)), and dexamethasone-induced increase in SOCE was reduced by the iPLA(2) inhibitor bromoenol lactone (BEL). In additional experiments, treatment of myotubes with the store-operated calcium channel inhibitor gadolinium ion or BEL reduced dexamethasone-induced increase in protein degradation. Taken together, the results suggest that glucocorticoids increase calcium concentrations in myocytes and stimulate iPLA(2)-dependent SOCE and that glucocorticoid-induced muscle protein degradation may at least in part be regulated by increased iPLA(2) activity, SOCE, and cellular calcium levels.
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Affiliation(s)
- Kiyoshi Itagaki
- Dept. of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Arabadzhiev TI, Dimitrov GV, Chakarov VE, Dimitrov AG, Dimitrova NA. Effects of changes in intracellular action potential on potentials recorded by single-fiber, macro, and belly-tendon electrodes. Muscle Nerve 2008; 37:700-12. [PMID: 18506714 DOI: 10.1002/mus.21024] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Some myopathies are accompanied by abnormal calcium homeostasis. Electromyography (EMG) in such patients shows signs of normal or myopathic EMG when detected by a single-fiber electrode and abnormally increased values in macro EMG. As calcium accumulation might be accompanied by changes in intracellular action potential (IAP) and muscle-fiber propagation velocity, we simulated the effects of such changes on motor unit potentials (MUPs) recorded by different kinds of electrodes. We found that: (1) the requirements for what potential can be accepted as a single-fiber action potential (SFAP) are too rigorous; (2) macro MUP amplitude can increase while SFAP amplitude can decrease when there is an increase in the spatial length of IAP spike; and (3) changes in the second phase of a belly-tendon-detected MUP or M wave could be used for noninvasive detection of increased IAP depolarizing (negative) after-potential.
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Affiliation(s)
- Todor I Arabadzhiev
- Centre of Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 105, Sofia 1113, Bulgaria.
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Li Y, Zhang C, Xiong F, Yu MJ, Peng FL, Shang YC, Zhao CP, Xu YF, Liu ZS, Zhou C, Wu JL. Comparative study of mesenchymal stem cells from C57BL/10 and mdx mice. BMC Cell Biol 2008; 9:24. [PMID: 18489762 PMCID: PMC2415111 DOI: 10.1186/1471-2121-9-24] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 05/19/2008] [Indexed: 12/20/2022] Open
Abstract
Background Human mesenchymal stem cells (MSCs) have been studied and applied extensively because of their ability to self-renew and differentiate into various cell types. Since most human diseases models are murine, mouse MSCs should have been studied in detail. The mdx mouse – a Duchenne muscular dystrophy model – was produced by introducing a point mutation in the dystrophin gene. To understand the role of dystrophin in MSCs, we compared MSCs from mdx and C57BL/10 mice, focusing particularly on the aspects of light and electron microscopic morphology, immunophenotyping, and differentiation potential. Results Our study showed that at passage 10, mdx-MSCs exhibited increased heterochromatin, larger vacuoles, and more lysosomes under electron microscopy compared to C57BL/10-MSCs. C57BL/10-MSCs formed a few myotubes, while mdx-MSCs did not at the same passages. By passage 21, mdx-MSCs but not C57BL/10-MSCs had gradually lost their proliferative ability. In addition, a significant difference in the expression of CD34, not Sca-1 and CD11b, was observed between the MSCs from the 2 mice. Conclusion Our current study reveals that the MSCs from the 2 mice, namely, C57BL/10 and mdx, exhibit differences in proliferative and myogenic abilities. The results suggest that the changes in mouse MSC behavior may be influenced by lack of dystrophin protein in mdx mouse.
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Affiliation(s)
- Yong Li
- Department of Neurology, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, ProC.
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Vandebrouck A, Sabourin J, Rivet J, Balghi H, Sebille S, Kitzis A, Raymond G, Cognard C, Bourmeyster N, Constantin B. Regulation of capacitative calcium entries by α1‐syntrophin: association of TRPC1 with dystrophin complex and the PDZ domain of α1‐syntrophin. FASEB J 2007; 21:608-17. [PMID: 17202249 DOI: 10.1096/fj.06-6683com] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Calcium mishandling in Duchenne dystrophic muscle suggested that dystrophin, a membrane-associated cytoskeleton protein, might regulate calcium signaling cascade such as calcium influx pathway. It was previously shown that abnormal calcium entries involve uncontrolled stretch-activated currents and store-operated Ca2+ currents supported by TRPC1 channels. Moreover, our recent work demonstrated that reintroduction of minidystrophin in dystrophic myotubes restores normal capacitative calcium entries (CCEs). However, until now, no molecular link between the dystrophin complex and calcium entry channels has been described. This study is the first to show by coimmunoprecipitation assays the molecular association of TRPC1 with dystrophin and alpha1-syntrophin in muscle cells. TRPC1 was also associated with alpha1-syntrophin in dystrophic muscle cells independently of dystrophin. Furthermore, glutathione S-transferase (GST) pull-down assays showed that TRPC1 binds to the alpha1-syntrophin PDZ domain. Transfected recombinant alpha1-syntrophin formed a complex with TRPC1 channels and restored normal CCEs in dystrophic muscle cells. We suggest that normal regulation of CCEs in skeletal muscle depends on the association between TRPC1 channels and alpha1-syntrophin that may anchor the store-operated channels to the dystrophin-associated protein complex (DAPC). The loss of this molecular association could participate in the calcium alterations observed in dystrophic muscle cells. This study provides a new model for the regulation of calcium influx by interaction with the scaffold of the DAPC in muscle cells.
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Affiliation(s)
- Aurélie Vandebrouck
- Institut de Physiologie et Biologie Cellulaires, CNRS, UMR-6187, University of Poitiers, 86022 Poitiers, France
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Hopf FW, Turner PR, Steinhardt RA. Calcium misregulation and the pathogenesis of muscular dystrophy. Subcell Biochem 2007; 45:429-464. [PMID: 18193647 DOI: 10.1007/978-1-4020-6191-2_16] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Although the exact nature of the relationship between calcium and the pathogenesis of Duchenne muscular dystrophy (DMD) is not fully understood, this is an important issue which has been addressed in several recent reviews (Alderton and Steinhardt, 2000a, Gailly, 2002, Allen et al., 2005). A key question when trying to understand the cellular basis of DMD is how the absence or low level of expression of dystrophin, a cytoskeletal protein, results in the slow but progressive necrosis of muscle fibres. Although loss of cytoskeletal and sarcolemmal integrity which results from the absence of dystrophin clearly plays a key role in the pathogenesis associated with DMD, a number of lines of evidence also establish a role for misregulation of calcium ions in the DMD pathology, particularly in the cytoplasmic space just under the sarcolemma. A number of calcium-permeable channels have been identified which can exhibit greater activity in dystrophic muscle cells, and exIsting evidence suggests that these may represent different variants of the same channel type (perhaps the transient receptor potential channel, TRPC). In addition, a prominent role for calcium-activated proteases in the DMD pathology has been established, as well as modulation of other intracellular regulatory proteins and signaling pathways. Whether dystrophin and its associated proteins have a direct role in the regulation of calcium ions, calcium channels or intracellular calcium stores, or indirectly alters calcium regulation through enhancement of membrane tearing, remains unclear. Here we focus on areas of consensus or divergence amongst the existing literature, and propose areas where future research would be especially valuable.
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Affiliation(s)
- F W Hopf
- Ernest Gallo Clinic and Research Center, University of California, San Francisco, 5858 Horton St., Suite 200, Emeryville, CA 94608, USA.
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Rolland JF, De Luca A, Burdi R, Andreetta F, Confalonieri P, Conte Camerino D. Overactivity of exercise-sensitive cation channels and their impaired modulation by IGF-1 in mdx native muscle fibers: beneficial effect of pentoxifylline. Neurobiol Dis 2006; 24:466-74. [PMID: 17010631 DOI: 10.1016/j.nbd.2006.08.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 08/01/2006] [Accepted: 08/14/2006] [Indexed: 11/17/2022] Open
Abstract
Cell-attached patch-clamp recordings on native striated myofibers from adult dystrophic mdx mice revealed a higher occurrence and open probability compared to non-dystrophic wild-type myofibers of a 30 pS voltage-insensitive Ca2+-permeable channel, inhibited by Gd3+, streptomycin and ruthenium red. Myofibers from in vivo exercised animals had higher channel occurrence and/or open probability. Insulin-like growth factor 1 (3.3 nM) induced and/or enhanced channel activity, via PI3 kinase, in wild-type but not in mdx myofibers. Interestingly, in both genotypes the current was silenced by db-cAMP or pentoxifylline, a phosphodiesterase inhibitor. The channel activity/occurrence in pentoxifylline-treated exercised mdx (50 mg/kg/day i.p. for 4-8 weeks) overlapped that of exercised wild-type mice. Thus, a growth factor-sensitive current, likely due to a TRP channel, is activated in vivo by exercise in native striated fibers; its deregulation in the absence of dystrophin may contribute to Ca2+ homeostasis alteration. The possibility to pharmacologically counteract abnormal channel activity discloses important therapeutic application.
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Affiliation(s)
- Jean-François Rolland
- Unit of Pharmacology, Department of Pharmacobiology, Faculty of Pharmacy, University of Bari, Bari, Italy
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Moussa CEH, Fu Q, Kumar P, Shtifman A, Lopez JR, Allen PD, LaFerla F, Weinberg D, Magrane J, Aprahamian T, Walsh K, Rosen KM, Querfurth HW. Transgenic expression of B‐APP in fast‐twitch skeletal muscle leads to calcium dyshomeostasis and IBM‐like pathology. FASEB J 2006; 20:2165-7. [PMID: 16940437 DOI: 10.1096/fj.06-5763fje] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Intracellular deposition of the beta-amyloid (Abeta) peptide is an increasingly recognized pathological hallmark associated with neurodegeneration and muscle wasting in Alzheimer's disease (AD) and inclusion body myositis (IBM), respectively. Previous reports have implicated dysregulation of beta-amyloid precursor protein (betaAPP) expression in IBM. Accumulation of full-length betaAPP, its various proteolytic derivatives including Abeta, and phospho-tau into vacuolated inclusions is an early pathogenic event. We previously reported on a statistical tendency favoring fast twitch fiber involvement in IBM, reminiscent of the tissue specific patterns of misfolded protein deposition seen in neurodegenerative diseases. To test this principle, we generated an animal model in which human wild-type (WT) betaAPP expression was limited to postnatal type II skeletal muscle. Hemizygous transgenic mice harboring increased levels of holo betaAPP751 and Abeta in skeletal muscle fibers became significantly weaker with age compared with nontransgenic littermates and exhibited typical myopathic features. A subpopulation of dissociated muscle fibers from transgenic mice exhibited a 2-fold increase in resting calcium and membrane depolarization compared with nontransgenic littermates. Taken together, these data indicate that overexpression of human betaAPP in fast twitch skeletal muscle of transgenic mice is sufficient for the development of some features characteristic of IBM, including abnormal tau histochemistry. The increase in resting calcium and depolarization are novel findings, suggesting both a mechanism for the weakness and an avenue for therapeutic intervention in IBM.
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Affiliation(s)
- Charbel E-H Moussa
- Department of Neurology, Caritas St. Elizabeth's Medical Center of Boston, Tufts University School of Medicine, 736 Cambridge St., Boston, MA, USA
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40
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Constantin B, Sebille S, Cognard C. New insights in the regulation of calcium transfers by muscle dystrophin-based cytoskeleton: implications in DMD. J Muscle Res Cell Motil 2006; 27:375-86. [PMID: 16897576 DOI: 10.1007/s10974-006-9085-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Accepted: 06/28/2006] [Indexed: 01/18/2023]
Abstract
Calcium mishandling in Duchenne muscular dystrophy (DMD) suggested that dystrophin, a membrane-associated cytoskeleton protein, may regulate calcium-signalling cascades such as calcium entries. Calcium overload in human DMD myotubes is dependent on their contractile activity suggesting the involvement of channels being activated during contraction and/or calcium release. Forced expression of mini-dystrophin in dystrophin-deficient myotubes, reactivates appropriate sarcolemmal expression of dystrophin-associated proteins and restores normal calcium handling in the cytosol. Furthermore, the recombinant mini-dystrophin reduced the store-operated calcium influx across the sarcolemma, and the mitochondrial calcium uptake during this influx. A slow component of calcium release dependent on IP3R, as well as the production of IP3, were also reduced to normal levels by expression of mini-dystrophin. Our studies provide a new model for the convergent regulation of transmembrane calcium influx and IP3-dependent calcium release by the dystrophin-based cytoskeleton (DBC). We also suggest molecular association of such channels with DBC which may provide the scaffold for assembling a multiprotein-signalling complex that modulates the channel activity. This suggests that the loss of this molecular association could participate in the alteration of calcium homeostasis observed in DMD muscle cells.
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Affiliation(s)
- Bruno Constantin
- Institut de Physiologie et Biologie Cellulaires, CNRS, UMR-6187, University of Poitiers, 86022, Poitiers, France.
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41
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Balghi H, Sebille S, Mondin L, Cantereau A, Constantin B, Raymond G, Cognard C. Mini-dystrophin expression down-regulates IP3-mediated calcium release events in resting dystrophin-deficient muscle cells. ACTA ACUST UNITED AC 2006; 128:219-30. [PMID: 16847098 PMCID: PMC2151532 DOI: 10.1085/jgp.200609559] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We present here evidence for the enhancement, at rest, of an inositol 1,4,5-trisphosphate (IP3)–mediated calcium signaling pathway in myotubes from dystrophin-deficient cell lines (SolC1(−)) as compared to a cell line from the same origin but transfected with mini-dystrophin (SolD(+)). With confocal microscopy, the number of sites discharging calcium (release site density [RSD]) was quantified and found more elevated in SolC1(−) than in SolD(+) myotubes. Variations of membrane potential had no significant effect on this difference, and higher resting [Ca2+]i in SolC1(−) (Marchand, E., B. Constantin, H. Balghi, M.C. Claudepierre, A. Cantereau, C. Magaud, A. Mouzou, G. Raymond, S. Braun, and C. Cognard. 2004. Exp. Cell Res. 297:363–379) cannot explain alone higher RSD. The exposure with SR Ca2+ channel inhibitors (ryanodine and 2-APB) and phospholipase C inhibitor (U73122) significantly reduced RSD in both cell types but with a stronger effect in dystrophin-deficient SolC1(−) myotubes. Immunocytochemistry allowed us to localize ryanodine receptors (RyRs) as well as IP3 receptors (IP3Rs), IP3R-1 and IP3R-2 isoforms, indicating the presence of both RyRs-dependent and IP3-dependent release systems in both cells. We previously reported evidence for the enhancement, through a Gi protein, of the IP3-mediated calcium signaling pathway in SolC1(−) as compared to SolD(+) myotubes during a high K+ stimulation (Balghi, H., S. Sebille, B. Constantin, S. Patri, V. Thoreau, L. Mondin, E. Mok, A. Kitzis, G. Raymond, and C. Cognard. 2006. J. Gen. Physiol. 127:171–182). Here we show that, at rest, these regulation mechanisms are also involved in the modulation of calcium release activities. The enhancement of resting release activity may participate in the calcium overload observed in dystrophin-deficient myotubes, and our findings support the hypothesis of the regulatory role of mini-dystrophin on intracellular signaling.
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MESH Headings
- Animals
- Calcium/metabolism
- Calcium Channel Blockers/pharmacology
- Calcium Channels/analysis
- Calcium Channels/physiology
- Calcium Signaling/physiology
- Cell Line
- Chelating Agents/pharmacology
- Cytoplasm/metabolism
- Down-Regulation
- Dystrophin/deficiency
- Dystrophin/genetics
- Dystrophin/physiology
- Egtazic Acid/analogs & derivatives
- Egtazic Acid/pharmacology
- Estrenes/pharmacology
- Inositol 1,4,5-Trisphosphate Receptors
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Mice
- Mice, Inbred C3H
- Mice, Knockout
- Microscopy, Confocal
- Muscle, Skeletal/cytology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Nuclear Envelope/metabolism
- Phosphodiesterase Inhibitors/pharmacology
- Potassium/pharmacology
- Pyrrolidinones/pharmacology
- Receptors, Cytoplasmic and Nuclear/analysis
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/physiology
- Ryanodine/pharmacology
- Ryanodine Receptor Calcium Release Channel/metabolism
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Affiliation(s)
- Haouaria Balghi
- Institut de Physiologie et Biologie Cellulaires, CNRS UMR 6187, Université de Poitiers, 86022 Poitiers, France
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Lansman JB, Franco-Obregón A. MECHANOSENSITIVE ION CHANNELS IN SKELETAL MUSCLE: A LINK IN THE MEMBRANE PATHOLOGY OF MUSCULAR DYSTROPHY. Clin Exp Pharmacol Physiol 2006; 33:649-56. [PMID: 16789935 DOI: 10.1111/j.1440-1681.2006.04393.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Mechanosensitive (MS) channels are expressed abundantly in skeletal muscle at all stages of development. In recordings from membrane patches, MS channels are constitutively active at the resting potential. The channels are selective for cations and have a large single-channel conductance (approximately 25 pS in physiological saline) and a high Ca2+ permeability (relative permeability of Ca2+ to K+ (PCa/PK) = 7). 2. Mechanosensitive channel activity recorded from the surface of myotubes from dystrophic mdx mice was substantially greater than the activity recorded from wild-type myotubes. Increased channel activity in the mutant results from the induction in a subpopulation of channels of a novel MS gating mode characterized by markedly prolonged channel openings and inactivation in response to membrane stretch. 3. Membrane stretch or a strong depolarization causes an irreversible switch to the stretch-inactivated gating mode in mdx myotubes. A stretch-induced shift in MS channel gating mode may contribute to stretch-induced elevations in [Ca2+]i during the early stages of disease pathogenesis. 4. Abnormalities of MS channel behaviour are also detected in recordings from patches on flexor digitorum brevis fibres acutely isolated from mdx mice. Mechanosensitive channel opening probability is higher in mdx fibres at all developmental stages. In addition, channel numbers are persistently elevated during postnatal development, failing to undergo a normal process of downregulation during the first 3 postnatal weeks. 5. Two distinct mechanisms may contribute to elevations of [Ca2+]i in dystrophin-deficient skeletal muscle: (i) a membrane stress-dependent switch of MS channels into to a prolonged opening mode; and (ii) a loss of developmental downregulation leading to persistent MS channel expression during postnatal muscle development.
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Affiliation(s)
- Jeffry B Lansman
- Department of Cellular and Molecular Pharmacology, UCSF School of Medicine, San Francisco, California 94143-0450, USA.
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43
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Basset O, Boittin FX, Cognard C, Constantin B, Ruegg U. Bcl-2 overexpression prevents calcium overload and subsequent apoptosis in dystrophic myotubes. Biochem J 2006; 395:267-76. [PMID: 16393138 PMCID: PMC1422769 DOI: 10.1042/bj20051265] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a lethal disease caused by the lack of the cytoskeletal protein dystrophin. Altered calcium homoeostasis and increased calcium concentrations in dystrophic fibres may be responsible for the degeneration of muscle occurring in DMD. In the present study, we used subsarcolemmal- and mitochondrial-targeted aequorin to study the effect of the antiapoptotic Bcl-2 protein overexpression on carbachol-induced near-plasma membrane and mitochondrial calcium responses in myotubes derived from control C57 and dystrophic (mdx) mice. We show that Bcl-2 overexpression decreases subsarcolemmal and mitochondrial calcium overload that occurs during activation of nicotinic acetylcholine receptors in dystrophic myotubes. Moreover, our results suggest that overexpressed Bcl-2 protein may prevent near-plasma membrane and mitochondrial calcium overload by inhibiting IP3Rs (inositol 1,4,5-trisphosphate receptors), which we have shown previously to be involved in abnormal calcium homoeostasis in dystrophic myotubes. Most likely as a consequence, the inhibition of IP3R function by Bcl-2 also inhibits calcium-dependent apoptosis in these cells.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Calcium/metabolism
- Calcium Channels
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Cells, Cultured
- Gene Expression
- Inositol 1,4,5-Trisphosphate/pharmacology
- Inositol 1,4,5-Trisphosphate Receptors
- Mice
- Mice, Inbred C57BL
- Mice, Inbred mdx
- Mitochondria/metabolism
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/pathology
- Muscular Dystrophy, Animal/metabolism
- Muscular Dystrophy, Animal/pathology
- Protein Transport
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Staurosporine/pharmacology
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Affiliation(s)
- Olivier Basset
- *Laboratory of Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - François-Xavier Boittin
- *Laboratory of Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - Christian Cognard
- †Institut de Physiologie et Biologie Cellulaire, CNRS-UMR6187, University of Poitiers, 86022 Poitiers Cedex, France
| | - Bruno Constantin
- †Institut de Physiologie et Biologie Cellulaire, CNRS-UMR6187, University of Poitiers, 86022 Poitiers Cedex, France
| | - Urs T. Ruegg
- *Laboratory of Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
- To whom correspondence should be addressed (email )
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44
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Balghi H, Sebille S, Constantin B, Patri S, Thoreau V, Mondin L, Mok E, Kitzis A, Raymond G, Cognard C. Mini-dystrophin expression down-regulates overactivation of G protein-mediated IP3 signaling pathway in dystrophin-deficient muscle cells. ACTA ACUST UNITED AC 2006; 127:171-82. [PMID: 16446505 PMCID: PMC2151485 DOI: 10.1085/jgp.200509456] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present here evidence for the enhancement of an inositol 1,4,5-trisphosphate (IP3) mediated calcium signaling pathway in myotubes from dystrophin-deficient cell lines (SolC1(−)) as compared to a cell line from the same origin but transfected with mini-dystrophin (SolD(+)). With confocal microscopy, we demonstrated that calcium rise, induced by the perifusion of a solution containing a high potassium concentration, was higher in SolC1(−) than in SolD(+) myotubes. The analysis of amplitude and kinetics of the calcium increase in SolC1(−) and in SolD(+) myotubes during the exposure with SR Ca2+ channel inhibitors (ryanodine and 2-APB) suggested the presence of two mechanisms of SR calcium release: (1) a fast SR calcium release that depended on ryanodine receptors and (2) a slow SR calcium release mediated by IP3 receptors. Detection analyses of mRNAs (reverse transcriptase [RT]-PCR) and proteins (Western blot and immunolocalization) demonstrated the presence of the three known isoforms of IP3 receptors in both SolC1(−) and SolD(+) myotubes. Furthermore, analysis of the kinetics of the rise in calcium revealed that the slow IP3-dependent release may be increased in the SolC1(−) as compared to the SolD(+), suggesting an inhibitory effect of mini-dystrophin in this signaling pathway. Upon incubation with pertussis toxin (PTX), an inhibitory effect similar to that of the IP3R inhibitor (2-APB) was observed on K+-evoked calcium release. This result suggests the involvement of a Gi protein upstream of the IP3 pathway in these stimulation conditions. A hypothetical model is depicted in which both Gi protein and IP3 production could be involved in K+-evoked calcium release as well as a possible interaction with mini-dystrophin. Our findings demonstrate the existence of a potential relationship between mini-dystrophin and SR calcium release as well as a regulatory role of mini-dystrophin on intracellular signaling.
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MESH Headings
- Animals
- Blotting, Western
- Calcium/metabolism
- Calcium Channels/analysis
- Calcium Channels/chemistry
- Calcium Channels/drug effects
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Calcium Channels/physiology
- Calcium Signaling
- Cell Line
- Down-Regulation
- Dystrophin/analysis
- Dystrophin/deficiency
- Dystrophin/genetics
- Dystrophin/physiology
- GTP-Binding Protein alpha Subunits, Gi-Go/physiology
- GTP-Binding Proteins/physiology
- Gene Expression
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Mice
- Mice, Inbred C3H
- Microscopy, Confocal
- Muscle Fibers, Skeletal/metabolism
- Pertussis Toxin/pharmacology
- Potassium/pharmacology
- RNA, Messenger/analysis
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Ryanodine Receptor Calcium Release Channel/physiology
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Affiliation(s)
- Haouaria Balghi
- Institut de Physiologie et Biologie Cellulaires, CNRS UMR 6187, Université de Poitiers, France
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45
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Vandebrouck A, Ducret T, Basset O, Sebille S, Raymond G, Ruegg U, Gailly P, Cognard C, Constantin B. Regulation of store-operated calcium entries and mitochondrial uptake by minidystrophin expression in cultured myotubes. FASEB J 2005; 20:136-8. [PMID: 16254044 DOI: 10.1096/fj.04-3633fje] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Defective expression of dystrophin in muscle cells is the primary feature of Duchenne muscular dystrophy (DMD), which is accompanied by fiber necrosis and intracellular calcium mishandling. These features led to the hypothesis that dystrophin could control calcium movements. Calcium mishandling in human DMD myotubes is dependent on contraction and/or calcium release activity, suggesting the involvement of channels being activated during these processes. Forced expression of minidystrophin at the plasma membrane of dystrophin-deficient Sol8 myotubes reactivates appropriate sarcolemmal expression of dystrophin-associated proteins and results in normal calcium homeostasis. In active dystrophic myotubes, store-operated calcium channels could be responsible for a sustained calcium influx in muscle cells. We show here that depletion of calcium stores (sarcoplasmic reticulum) by repetitive activation of calcium release and blockade of SERCA leads to a calcium influx. In myotubes expressing recombinant minidystrophin, these store-dependent influxes were reduced to a level similar to that observed in myotubes expressing native dystrophin. High store-dependent calcium influxes in dystrophin-deficient myotubes were associated with sustained cytosolic calcium transients and high intramitochondrial entries, while lower store-dependent calcium influx in myotubes expressing minidystrophin resulted in shorter calcium transients and reduced calcium uptake into mitochondria. We propose that minidystrophin negatively regulates sarcolemmal store-dependent calcium channels, which reduces store-dependent calcium influx, as well as its mitochondrial uptake. Forced expression of minidystrophin in dystrophic cells might restore the regulation of sarcolemmal store-dependent channels, which could protect against calcium mishandling.
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Affiliation(s)
- A Vandebrouck
- Institut de Physiologie et Biologie Cellulaires, CNRS, UMR-6187, University of Poitiers, Poitiers, France
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46
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Zimowska M, Constantin B, Papy-Garcia D, Raymond G, Cognard C, Caruelle JP, Moraczewski J, Martelly I. Novel glycosaminoglycan mimetic (RGTA, RGD120) contributes to enhance skeletal muscle satellite cell fusion by increasing intracellular Ca2+ and calpain activity. J Cell Physiol 2005; 205:237-45. [PMID: 15887234 DOI: 10.1002/jcp.20403] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Glycosaminoglycans (GAG) are classes of molecules that play an important role in cellular processes. The use of GAG mimetics called regenerating agent (RGTA) represents a tool to investigate the effect of GAG moiety on cellular behavior. A first member of the RGTA family (RG1192), a dextran polymers with defined amounts of sulfate, carboxymethyl, as well as hydrophobic groups (benzylamide), was shown to stimulate skeletal muscle repair after damage and myoblast differentiation. To obtain a comprehensive insight into the mechanism of action of GAG mimetics, we investigated the effect on myoblast differentiation of a novel RGTA, named RGD120, which was devoid of hydrophobic substitution and had ionic charge similar to heparin. Myoblasts isolated from adult rat skeletal muscles and grown in primary cultures were used in this study. We found that chronic treatment with RGD120 increased the growth of adult myoblasts and induced their precocious fusion into myotubes in vitro. It also partially overcame the inhibitory effect of the calpain inhibitor N-acetyl-leu-leu-norleucinal (ALLN) on these events. Western blot and zymography analyses revealed that milli calpain was slightly increased by RGD120 chronic treatment. In addition, using fluorescent probes (Indo-1 and Boc-leu-met-MAC), we demonstrated that RGD120 added to prefusing myoblast cultures accelerates myoblast fusion into myotubes, induced an increase of cytosolic free calcium concentration, and concomitantly an increase of intracellular calpain protease activity. Altogether, these results suggested that the efficiency of RGD120 in stimulating myogenesis might be in part explained through its effect on calcium mobilization as well as on the calpain amount and activity.
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MESH Headings
- Animals
- Blotting, Western
- Calcium/metabolism
- Calpain/analysis
- Calpain/metabolism
- Cell Differentiation
- Cell Extracts/pharmacology
- Cell Fusion
- Cells, Cultured
- Dose-Response Relationship, Drug
- Fluorescence
- Glycosaminoglycans/chemistry
- Glycosaminoglycans/pharmacology
- Immunohistochemistry
- Male
- Molecular Mimicry
- Muscle, Skeletal/cytology
- Myoblasts, Skeletal/cytology
- Myoblasts, Skeletal/drug effects
- Myoblasts, Skeletal/physiology
- Rats
- Rats, Wistar
- Satellite Cells, Skeletal Muscle/cytology
- Spectrometry, Fluorescence
- Time Factors
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Affiliation(s)
- M Zimowska
- Department of Cytology, Faculty of Biology, Warsaw University, Poland
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47
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Fraysse B, Liantonio A, Cetrone M, Burdi R, Pierno S, Frigeri A, Pisoni M, Camerino C, De Luca A. The alteration of calcium homeostasis in adult dystrophic mdx muscle fibers is worsened by a chronic exercise in vivo. Neurobiol Dis 2004; 17:144-54. [PMID: 15474352 DOI: 10.1016/j.nbd.2004.06.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2003] [Revised: 05/14/2004] [Accepted: 06/03/2004] [Indexed: 11/24/2022] Open
Abstract
Chronic exercise in vivo aggravates dystrophy in mdx mice. Calcium homeostasis was evaluated ex vivo by micro-spectrofluorometry on tendon-to-tendon dissected extensor digitorum longus (EDL) muscle fibers. Resting cytosolic calcium ([Ca2+]i) and sarcolemmal permeability through Gd3+ -sensitive mechanosensitive calcium (MsCa) channel were significantly higher in mdx vs. wild-type fibers. The exercise further enhanced [Ca2+]i in mdx fibers and increased sarcolemmal permeability by activating nifedipine-sensitive leak calcium channels. The two genotypes did not differ in caffeine sensitivity and in the excitation-calcium release (ECaR) coupling mechanism by K+ depolarization. The exercise produced a similar adaptation of activation curve of ECaR and of sensitivity to caffeine. However, the inactivation of ECaR of mdx fibers did not adapt to exercise. No fiber phenotype transition occurred in exercised muscle. We provide the first evidence that an in vivo exercise worsens the impaired calcium homeostasis of dystrophic fibers, supporting the role of enhanced calcium entrance in dystrophic progression.
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Affiliation(s)
- Bodvael Fraysse
- Unit of Pharmacology, Department of Pharmacobiology, Faculty of Pharmacy, University of Bari, Bari, Italy
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48
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Marchand E, Constantin B, Balghi H, Claudepierre MC, Cantereau A, Magaud C, Mouzou A, Raymond G, Braun S, Cognard C. Improvement of calcium handling and changes in calcium-release properties after mini- or full-length dystrophin forced expression in cultured skeletal myotubes. Exp Cell Res 2004; 297:363-79. [PMID: 15212940 DOI: 10.1016/j.yexcr.2004.02.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2003] [Revised: 01/30/2004] [Indexed: 10/26/2022]
Abstract
Dystrophin is a cytoskeletal protein normally expressed underneath the sarcolemma of muscle fibers. The lack of dystrophin in Duchenne muscular Dystrophy (DMD) muscles results in fiber necrosis, which was proposed to be mediated by chronic calcium mishandling. The extensive comparison of dystrophic cells from human or mdx mice with normal muscles have suggested that the lack of dystrophin may alter the resting calcium permeability and steady-state levels of calcium, but this latter observation remains controversial. It is also not clear, whether calcium mishandling is resulting from the dystrophic process or if dystrophin can directly regulate calcium handling in muscle cells. This prompted us to determine if transfection of full-length dystrophin or Becker Muscular Dystrophy (BMD) minidystrophin, a candidate for viral-mediated gene therapy, could change calcium handling properties. We took advantage of specific properties of Sol8 cell line showing the absence of dystrophin expression together with a drastic calcium mishandling. Here, we show that full-length dystrophin allowed the recovery of a low resting intracellular-free calcium concentration together with lower calcium transients. We also show for the first time that stable expression of minidystrophin was able to restore normal calcium handling in Sol8 myotubes through a better control of steady-state levels, calcium transients, and subcellular calcium events. It suggests that dystrophin could play a regulatory role on calcium homeostasis apparatus and that functional links exist between calcium signaling and cytoskeleton.
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MESH Headings
- Animals
- Calcium/metabolism
- Carbocyanines
- Cells, Cultured
- Dystrophin/genetics
- Dystrophin/metabolism
- Fluorescent Dyes
- Green Fluorescent Proteins
- Homeostasis
- Immunohistochemistry
- Luminescent Proteins
- Mice
- Mice, Inbred C3H
- Microinjections
- Microscopy, Confocal
- Muscle Fibers, Skeletal/cytology
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/pathology
- Muscle, Skeletal/cytology
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Dystrophy, Duchenne/pathology
- Plasmids
- Retroviridae/genetics
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Affiliation(s)
- Eric Marchand
- Institut de Physiologie et Biologie Cellulaire, UMR CNRS/Université de Poitiers 6187, Pôle Biologie Santé, 86022 Poitiers cedex, France
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49
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Deval E, Levitsky DO, Marchand E, Cantereau A, Raymond G, Cognard C. Na(+)/Ca(2+) exchange in human myotubes: intracellular calcium rises in response to external sodium depletion are enhanced in DMD. Neuromuscul Disord 2002; 12:665-73. [PMID: 12207936 DOI: 10.1016/s0960-8966(02)00022-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study aims to investigate the sodium/calcium exchanger expression in human co-cultured skeletal muscle cells and to compare the effects of Na(+)/Ca(2+) exchange activity in normal and dystrophic (Duchenne's muscular dystrophy) human co-cultured myotubes. For this purpose, variations of intracellular calcium concentration ([Ca(2+)](int)) were monitored, as the variations of the fluorescence ratio of indo-1 probe, in response to external sodium depletion. External sodium withdrawal induced [Ca(2+)](int) rises within several seconds in both normal and Duchenne's muscular dystrophy myotubes. These Na(+)-free-induced [Ca(2+)](int) elevations were attributed to the reverse mode of the Na(+)/Ca(2+) exchange mechanism since the phenomenon was dependent on extracellular calcium concentration ([Ca(2+)](ext)), and since it was sensitive to external Ni(2+) ions. Amplitudes of Na(+)-free-induced [Ca(2+)](int) rises were significantly greater in Duchenne's muscular dystrophy cells than in normal ones. Such a difference disappeared when the sarcoplasmic reticulum was pharmacologically blocked, suggesting that the reverse mode of the Na(+)/Ca(2+) exchange mechanism was able to generate enhanced calcium-induced calcium-release in Duchenne's muscular dystrophy myotubes. Immunostaining images of Na(+)/Ca(2+) exchanger (NCX) isoforms, obtained by confocal microscopy, revealed the presence of NCX1 and NCX3 at the sarcolemmal level of both normal and Duchenne's muscular dystrophy myotubes. No differences were observed in the location of NCX isoforms expression between normal and Duchenne's muscular dystrophy co-cultured myotubes.
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Affiliation(s)
- Emmanuel Deval
- Laboratoire des Biomembranes et Signalisation Cellulaire, UMR CNRS 6558, Université de Poitiers, 40 avenue du Recteur Pineau, 86022 Cedex, Poitiers, France
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Vandebrouck C, Duport G, Raymond G, Cognard C. Hypotonic medium increases calcium permeant channels activity in human normal and dystrophic myotubes. Neurosci Lett 2002; 323:239-43. [PMID: 11959428 DOI: 10.1016/s0304-3940(02)00148-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Duchenne muscular dystrophy (DMD) is characterized by the absence of dystrophin and an elevated intracellular calcium level. Single-channel recordings were performed with the cell-attached configuration of the patch-clamp technique. The present study shows, on human co-cultured normal and dystrophic muscle cells, the evidence for an increased activity of calcium permeant cationic mechano-sensitive channels under hypotonic medium stimulation. This activity was particularly enhanced in DMD cells. The hypotonic medium induced drastic changes in the single-channel activity characteristics, which are: a large increase of the calcium over potassium permeability ratio; and a great enhancement of the quantity of current crossing through these channels. These channels could contribute to a significant calcium entry, which could participate in the abnormal calcium homeostasis observed in DMD muscle.
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MESH Headings
- Adolescent
- Adult
- Calcium/metabolism
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Cation Transport Proteins/drug effects
- Cation Transport Proteins/metabolism
- Cations/pharmacology
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Cells, Cultured
- Child
- Child, Preschool
- Gadolinium/pharmacology
- Humans
- Hypotonic Solutions/pharmacology
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Middle Aged
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/pathology
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscle, Skeletal/physiopathology
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/physiopathology
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Affiliation(s)
- Clarisse Vandebrouck
- Laboratoire de Biomembranes et Signalisation Cellulaire, UMR CNRS/Université de Poitiers 6558, 86022 Poitiers Cedex, France.
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