1
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Sahai A, Jones DL, Hughes M, Pu A, Williams K, Iyer SR, Rathinam C, Davis DL, Lovering RM, Gilotra MN. Fibroadipogenic progenitor cell response peaks prior to progressive fatty infiltration after rotator cuff tendon tear. J Orthop Res 2022; 40:2743-2753. [PMID: 35239216 PMCID: PMC9440165 DOI: 10.1002/jor.25321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 02/22/2022] [Accepted: 03/01/2022] [Indexed: 02/04/2023]
Abstract
Fibroadipogenic progenitor (FAP) cells are implicated as a major source of fatty infiltration (FI) in murine rotator cuff (RC) injury, but FAP cell response after RC tear in a rabbit model is unknown. This study determined whether changes in FAP cell count after an RC tear predate muscle degeneration in a clinically relevant rabbit model. We hypothesized increases in FAP cell count correlate temporally with RC degeneration. New Zealand white rabbits (n = 26) were evaluated at 1, 2, 4, and 6 weeks after unilateral full-thickness tenotomy of supraspinatus and infraspinatus tendons. FI area and adipocyte size were histologically analyzed, muscle density was measured by computerized tomography, and quantification of FAP cells was measured by flow cytometry and immunohistochemistry. The percentage of intrafascicular adipocyte area increased over time in supraspinatus muscle samples (p = 0.03), significantly between 1- and 6-week samples (p = 0.04). There were no differences in perifascicular adipocyte area percentages between time points. Peak increase in FAP cell count occurred at 1-week (p = 0.03), with a decrease in the following weeks. There was a negative correlation between supraspinatus adipocyte area and FAP cell count (p < 0.05). On computed tomography (CT) scan, maximal decrease in muscle density was observed in the 4th to 6th weeks. In summary, FAP cell response occurred early after tenotomy and did not correlate temporally with increases in FI. This suggests that FAP cell response may predate degenerative changes, and early targeting of FAPs before adipocyte maturation could blunt FI after RC tear.
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Affiliation(s)
- Amil Sahai
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Derek L. Jones
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Marcus Hughes
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Alex Pu
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Katrina Williams
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Shama R. Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Chozha Rathinam
- Department of Immunology, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Derik L. Davis
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Richard M. Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
| | - Mohit N. Gilotra
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Baltimore, USA
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Iyer SR, Shah SB, Ward CW, Stains JP, Folker ES, Lovering RM. Inhibition of YAP signaling improves recovery in injured skeletal muscle. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r5346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Shama R. Iyer
- OrthopaedicsUniversity of Maryland School of MedicineBaltimoreMD
| | - Sameer B. Shah
- Departments of Orthopaedic Surgery and BioengineeringUniversity of California San DiegoSan DiegoCA
| | | | - Joseph P. Stains
- OrthopaedicsUniversity of Maryland School of MedicineBaltimoreMD
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Sun C, Kannan S, Choi IY, Lim H, Zhang H, Chen GS, Zhang N, Park SH, Serra C, Iyer SR, Lloyd TE, Kwon C, Lovering RM, Lim SB, Andersen P, Wagner KR, Lee G. Human pluripotent stem cell-derived myogenic progenitors undergo maturation to quiescent satellite cells upon engraftment. Cell Stem Cell 2022; 29:610-619.e5. [PMID: 35395188 PMCID: PMC9000524 DOI: 10.1016/j.stem.2022.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/10/2021] [Accepted: 03/09/2022] [Indexed: 12/19/2022]
Abstract
Human pluripotent stem cell (hPSC)-derived myogenic progenitor cell (MPC) transplantation is a promising therapeutic approach for a variety of degenerative muscle disorders. Here, using an MPC-specific fluorescent reporter system (PAX7::GFP), we demonstrate that hPSC-derived MPCs can contribute to the regeneration of myofibers in mice following local injury and in mice deficient of dystrophin (mdx). We also demonstrate that a subset of PAX7::GFP MPCs engraft within the basal lamina of regenerated myofibers, adopt a quiescent state, and contribute to regeneration upon reinjury and in mdx mouse models. This subset of PAX7::GFP MPCs undergo a maturation process and remodel their molecular characteristics to resemble those of late-stage fetal MPCs/adult satellite cells following in vivo engraftment. These in-vivo-matured PAX7::GFP MPCs retain a cell-autonomous ability to regenerate and can repopulate in the niche of secondary recipient mice, providing a proof of principle for future hPSC-based cell therapy for muscle disorders.
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Affiliation(s)
- Congshan Sun
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Genetic Muscle Disorders, The Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Suraj Kannan
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biomedical Engineering and Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - In Young Choi
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - HoTae Lim
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hao Zhang
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Grace S Chen
- Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Nancy Zhang
- Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Seong-Hyun Park
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Carlo Serra
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Genetic Muscle Disorders, The Kennedy Krieger Institute, Baltimore, MD 21205, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Thomas E Lloyd
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chulan Kwon
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biomedical Engineering and Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Su Bin Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Peter Andersen
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Kathryn R Wagner
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Genetic Muscle Disorders, The Kennedy Krieger Institute, Baltimore, MD 21205, USA.
| | - Gabsang Lee
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Abstract
Intermediate filaments (IFs) are a primary structural component of the cytoskeleton extending throughout the muscle cell (myofiber). Mechanotransduction, the process by which mechanical force is translated into a biochemical signal to activate downstream cellular responses, is crucial to myofiber function. Mechanical forces also act on the nuclear cytoskeleton, which is integrated with the myofiber cytoskeleton by the linker of the nucleoskeleton and cytoskeleton (LINC) complexes. Thus, the nucleus serves as the endpoint for the transmission of force through the cell. The nuclear lamina, a dense meshwork of lamin IFs between the nuclear envelope and underlying chromatin, plays a crucial role in responding to mechanical input; myofibers constantly respond to mechanical perturbation via signaling pathways by activation of specific genes. The nucleus is the largest organelle in cells and a master regulator of cell homeostasis, thus an understanding of how it responds to its mechanical environment is of great interest. The importance of the cell nucleus is magnified in skeletal muscle cells due to their syncytial nature and the extreme mechanical environment that muscle contraction creates. In this review, we summarize the bidirectional link between the organization of the nucleoskeleton and the contractile features of skeletal muscle as they relate to muscle function.
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Affiliation(s)
- Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Eric S Folker
- Department of Biology, Boston College, Chestnut Hill, MA, United States
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, United States.,Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
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Rovira Gonzalez YI, Moyer AL, LeTexier NJ, Bratti AD, Feng S, Peña V, Sun C, Pulcastro H, Liu T, Iyer SR, Lovering RM, O'Rourke B, Wagner KR. Mss51 deletion increases endurance and ameliorates histopathology in the mdx mouse model of Duchenne muscular dystrophy. FASEB J 2021; 35:e21276. [PMID: 33423297 DOI: 10.1096/fj.202002106rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/25/2020] [Accepted: 11/30/2020] [Indexed: 11/11/2022]
Abstract
Mitochondrial derangement is an important contributor to the pathophysiology of muscular dystrophies and may be among the earliest cellular deficits. We have previously shown that disruption of Mss51, a mammalian skeletal muscle protein that localizes to the mitochondria, results in enhanced muscle oxygen consumption rate, increased endurance capacity, and improved limb muscle strength in mice with wildtype background. Here, we investigate whether Mss51 deletion in the mdx murine model of Duchenne muscular dystrophy (mdx-Mss51 KO) counteracts the muscle pathology and mitochondrial irregularities observed in mdx mice. We found that mdx-Mss51 KO mice had increased myofiber oxygen consumption rates and an amelioration of muscle histopathology compared to mdx counterparts. This corresponded with greater treadmill endurance and less percent fatigue in muscle physiology, but no improvement in forelimb grip strength or limb muscle force production. These findings suggest that although Mss51 deletion ameliorates the skeletal muscle mitochondrial respiration defects in mdx and improves fatigue resistance in vivo, the lack of improvement in force production suggests that this target alone may be insufficient for a therapeutic effect.
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Affiliation(s)
- Yazmin I Rovira Gonzalez
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.,Cellular and Molecular Medicine Graduate Program, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Adam L Moyer
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.,Cellular and Molecular Medicine Graduate Program, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Nicolas J LeTexier
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA
| | - August D Bratti
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Siyuan Feng
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Vanessa Peña
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Congshan Sun
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.,Departments of Neurology and Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Hannah Pulcastro
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA
| | - Ting Liu
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Brian O'Rourke
- Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kathryn R Wagner
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, USA.,Departments of Neurology and Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
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Abstract
Isolated myofibers are commonly used to understand the function of skeletal muscle in vivo. This can involve single isolated myofibers obtained from dissection or from enzymatic dissociation. Isolation via dissection allows control of sarcomere length and preserves tendon attachment but is labor-intensive, time-consuming and yields few viable myofibers. In contrast, enzymatic dissociation is fast and facile, produces hundreds of myofibers, and more importantly reduces the number of muscles/animals needed for studies. Biomechanical properties of the sarcolemma have been studied using myofibers from the extensor digitorum longus, but this has been limited to dissected myofibers, making data collection slow and difficult. We have modified this tool to perform biomechanical measurements of the sarcolemma in dissociated myofibers from the flexor digitorum brevis.
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Affiliation(s)
- Karla P Garcia-Pelagio
- Departmento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Stephen JP Pratt
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Richard M Lovering
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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Iyer SR, Xu S, Shah SB, Lovering RM. Muscle phenotype of a rat model of Duchenne muscular dystrophy. Muscle Nerve 2020; 62:757-761. [PMID: 32918339 DOI: 10.1002/mus.27061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Our aim was to assess key muscle imaging and contractility parameters in the Duchenne muscular dystrophy (DMD) rat model (Dmd-KO rat), which have not yet been characterized sufficiently. METHODS We performed in-vivo magnetic resonance imaging (MRI) for thigh and leg muscles, and performed hematoxylin and eosin (H&E) staining and in-vivo muscle contractility testing in specific hindlimb muscles. RESULTS MRI prior to testing muscle contractility revealed multiple, unevenly distributed focal hyperintensities in the Dmd-KO rat quadriceps and tibialis anterior muscles. H&E staining showed corresponding areas of inflammation and ongoing regeneration. In-vivo contractile testing showed maximal force generated by Dmd-KO muscles was significantly lower, and susceptibility to injury was ~ two-fold greater in the Dmd-KO rats compared to wild-type (WT) rats. DISCUSSION Together, the MRI findings, histological findings, and the low strength and high susceptibility to injury in muscles support use of the Dmd-KO rat as an animal model of DMD.
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Affiliation(s)
- Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Lovering RM, Iyer SR, Edwards B, Davies KE. Alterations of neuromuscular junctions in Duchenne muscular dystrophy. Neurosci Lett 2020; 737:135304. [PMID: 32818587 DOI: 10.1016/j.neulet.2020.135304] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/09/2020] [Accepted: 08/11/2020] [Indexed: 12/18/2022]
Abstract
The focus of this review is on Duchenne muscular dystrophy (DMD), which is caused by the absence of the protein dystrophin and is characterized as a neuromuscular disease in which muscle weakness, increased susceptibility to muscle injury, and inadequate repair appear to underlie the pathology. Considerable attention has been dedicated to studying muscle fiber damage, but data show that both human patients and animal models for DMD present with fragmented neuromuscular junction (NMJ) morphology. In addition to pre- and post-synaptic abnormalities, studies indicate increased susceptibility of the NMJ to contraction-induced injury, with corresponding functional changes in neuromuscular transmission and nerve-evoked electromyographic activity. Such findings suggest that alterations in the NMJ of dystrophic muscle may play a role in muscle weakness via impairment of neuromuscular transmission. Further work is needed to fully understand the role of the NMJ in the weakness, susceptibility to injury, and progressive wasting associated with DMD.
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Affiliation(s)
- Richard M Lovering
- Departments of Orthopaedics and Physiology, University of Maryland School of Medicine, Baltimore, MD, USA; University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Shama R Iyer
- Departments of Orthopaedics and Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Benjamin Edwards
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Kay E Davies
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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Xu S, Tang S, Li X, Iyer SR, Lovering RM. Abnormalities in Brain and Muscle Microstructure and Neurochemistry of the DMD Rat Measured by in vivo Diffusion Tensor Imaging and High Resolution Localized 1H MRS. Front Neurosci 2020; 14:739. [PMID: 32760246 PMCID: PMC7372970 DOI: 10.3389/fnins.2020.00739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 06/22/2020] [Indexed: 12/03/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked disorder caused by the lack of dystrophin with progressive degeneration of skeletal muscles. Most studies regarding DMD understandably focus on muscle, but dystrophin is also expressed in the central nervous system, potentially resulting in cognitive and behavioral changes. Animal models are being used for developing more comprehensive neuromonitoring protocols and clinical image acquisition procedures. The recently developed DMD rat is an animal model that parallels the progressive muscle wasting seen in DMD. Here, we studied the brain and temporalis muscle structure and neurochemistry of wild type (WT) and dystrophic (DMD) rats using magnetic resonance imaging and spectroscopy. Both structural and neurochemistry alterations were observed in the DMD rat brain and the temporalis muscle. There was a decrease in absolute brain volume (WT = 1579 mm3; DMD = 1501 mm3; p = 0.039, Cohen’s d = 1.867), but not normalized (WT = 4.27; DMD = 4.02; p = 0.306) brain volume. Diffusion tensor imaging (DTI) revealed structural alterations in the DMD temporalis muscle, with increased mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD). In the DMD rat thalamus, DTI revealed an increase in fractional anisotropy (FA) and a decrease in RD. Smaller normalized brain volume correlated to severity of muscle dystrophy (r = −0.975). Neurochemical changes in the DMD rat brain included increased GABA and NAA in the prefrontal cortex, and GABA in the hippocampus. Such findings could indicate disturbed motor and sensory signaling, resulting in a dysfunctional GABAergic neurotransmission, and an unstable osmoregulation in the dystrophin-null brain.
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Affiliation(s)
- Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.,Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Shiyu Tang
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.,Center for Advanced Imaging Research, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Xin Li
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, United States
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Iyer SR, Scheiber AL, Yarowsky P, Frank Henn R, Otsuru S, Lovering RM. Exosomes Isolated From Platelet-rich Plasma And Mesenchymal Stem Cells Promote Functional Recovery After Muscle Injury. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000679516.67474.56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Iyer SR, Scheiber AL, Yarowsky P, Henn RF, Otsuru S, Lovering RM. Exosomes Isolated From Platelet-Rich Plasma and Mesenchymal Stem Cells Promote Recovery of Function After Muscle Injury. Am J Sports Med 2020; 48:2277-2286. [PMID: 32543878 DOI: 10.1177/0363546520926462] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Clinical use of platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) has gained momentum as treatment for muscle injuries. Exosomes, or small cell-derived vesicles, could be helpful if they could deliver the same or better physiological effect without cell transplantation into the muscle. HYPOTHESIS Local delivery of exosomes derived from PRP (PRP-exos) or MSCs (MSC-exos) to injured muscles hastens recovery of contractile function. STUDY DESIGN Controlled laboratory study. METHODS In a rat model, platelets were isolated from blood, and MSCs were isolated from bone marrow and expanded in culture; exosomes from both were isolated through ultracentrifugation. The tibialis anterior muscles were injured in vivo using maximal lengthening contractions. Muscles were injected with PRP-exos or MSC-exos (immediately after injury and 5 and 10 days after injury); controls received an equal volume of saline. Histological and biochemical analysis was performed on tissues for all groups. RESULTS Injury resulted in a significant loss of maximal isometric torque (66% ± 3%) that gradually recovered over 2 weeks. Both PRP-exos and MSC-exos accelerated recovery, with similar faster recovery of contractile function over the saline-treated group at 5, 10, and 15 days after injury (P < .001). A significant increase in centrally nucleated fibers was seen with both types of exosome groups by day 15 (P < .01). Genes involved in skeletal muscle regeneration were modulated by different exosomes. Muscles treated with PRP-exos had increased expression of Myogenin gene (P < .05), whereas muscles treated with MSC-exos had reduced expression of TGF-β (P < .05) at 10 days after muscle injury. CONCLUSION Exosomes derived from PRP or MSCs can facilitate recovery after a muscle strain injury in a small-animal model likely because of factors that can modulate inflammation, fibrosis, and myogenesis. CLINICAL RELEVANCE Given their small size, low immunogenicity, and ease with which they can be obtained, exosomes could represent a novel therapy for many orthopaedic ailments.
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Affiliation(s)
- Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Amanda L Scheiber
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Paul Yarowsky
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - R Frank Henn
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Satoru Otsuru
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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12
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Sun C, Choi IY, Rovira Gonzalez YI, Andersen P, Talbot CC, Iyer SR, Lovering RM, Wagner KR, Lee G. Duchenne muscular dystrophy hiPSC-derived myoblast drug screen identifies compounds that ameliorate disease in mdx mice. JCI Insight 2020; 5:134287. [PMID: 32343677 DOI: 10.1172/jci.insight.134287] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/23/2020] [Indexed: 12/18/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy. In the present study, when human induced pluripotent stem cells (hiPSCs) were differentiated into myoblasts, the myoblasts derived from DMD patient hiPSCs (DMD hiPSC-derived myoblasts) exhibited an identifiable DMD-relevant phenotype: myogenic fusion deficiency. Based on this model, we developed a DMD hiPSC-derived myoblast screening platform employing a high-content imaging (BD Pathway 855) approach to generate parameters describing morphological as well as myogenic marker protein expression. Following treatment of the cells with 1524 compounds from the Johns Hopkins Clinical Compound Library, compounds that enhanced myogenic fusion of DMD hiPSC-derived myoblasts were identified. The final hits were ginsenoside Rd and fenofibrate. Transcriptional profiling revealed that ginsenoside Rd is functionally related to FLT3 signaling, while fenofibrate is linked to TGF-β signaling. Preclinical tests in mdx mice showed that treatment with these 2 hit compounds can significantly ameliorate some of the skeletal muscle phenotypes caused by dystrophin deficiency, supporting their therapeutic potential. Further study revealed that fenofibrate could inhibit mitochondrion-induced apoptosis in DMD hiPSC-derived cardiomyocytes. We have developed a platform based on DMD hiPSC-derived myoblasts for drug screening and identified 2 promising small molecules with in vivo efficacy.
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Affiliation(s)
- Congshan Sun
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Center for Genetic Muscle Disorders, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland, USA
| | | | - Yazmin I Rovira Gonzalez
- Center for Genetic Muscle Disorders, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland, USA.,Cellular and Molecular Medicine Graduate Program, and
| | - Peter Andersen
- Institute for Cell Engineering.,Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - C Conover Talbot
- The Johns Hopkins School of Medicine Institute for Basic Biomedical Sciences, Baltimore, Maryland, USA
| | | | - Richard M Lovering
- Department of Orthopaedics and.,Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kathryn R Wagner
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Center for Genetic Muscle Disorders, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Gabsang Lee
- Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Institute for Cell Engineering
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Gilbert-Honick J, Iyer SR, Somers SM, Takasuka H, Lovering RM, Wagner KR, Mao HQ, Grayson WL. Engineering 3D skeletal muscle primed for neuromuscular regeneration following volumetric muscle loss. Biomaterials 2020; 255:120154. [PMID: 32562942 DOI: 10.1016/j.biomaterials.2020.120154] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/02/2020] [Accepted: 05/27/2020] [Indexed: 12/14/2022]
Abstract
Volumetric muscle loss (VML) overwhelms the native regenerative capabilities of skeletal muscle and has few effective treatments to regain lost muscle mass and function. Tissue engineered muscle constructs designed to promote neuromuscular regeneration are a promising therapeutic avenue. To date, there has been no engineered muscle construct for VML treatment that has incorporated a pharmacologic agent to promote neuromuscular regeneration. Here, we have modified electrospun fibrin microfiber bundles, which have demonstrated muscle regenerative potential, with the heparan sulfate proteoglycan, agrin, to stimulate innervation post-VML. Myoblasts cultured on microfiber bundles with either soluble or chemically tethered agrin demonstrated statistically significant increased clustering of acetylcholine receptors (AChRs) with soluble agrin displaying AChR clusters throughout the myofiber bundles, and tethered agrin displaying AChR clusters only at 10 μm from the substrate surface. Following implantation into murine VML defects for 4 weeks, constructs pre-treated with soluble or tethered agrin resulted in statistically significant increased neuromuscular junctions, regenerating myofibers, vascular infiltration, neural infiltration, and nuclear yes-associated protein (YAP) expression within the defect site compared to the control without agrin. The agrin-tethered microfiber bundles provided sustained agrin signaling within the regenerating site during the 4-week post-implantation periods and further augmented the density of regenerating myofibers in regenerated tissue with statistical significance compared to constructs with soluble agrin. These data demonstrate the neuromuscular regenerative potential of engineered muscle constructs pre-treated to induce AChR clustering with locally delivered agrin at the site of VML regeneration.
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Affiliation(s)
- Jordana Gilbert-Honick
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Shama R Iyer
- Department of Orthopedic Surgery, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
| | - Sarah M Somers
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hannah Takasuka
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Richard M Lovering
- Department of Orthopedic Surgery, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
| | - Kathryn R Wagner
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD 21205, USA; Graduate Program in Cellular and Molecular Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Departments of Neurology and Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hai-Quan Mao
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Materials Science & Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Institute for NanoBioTechnology (INBT), Johns Hopkins University School of Engineering, Baltimore, MD 21218, USA
| | - Warren L Grayson
- Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Materials Science & Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Institute for NanoBioTechnology (INBT), Johns Hopkins University School of Engineering, Baltimore, MD 21218, USA.
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14
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Wang Q, Hernandez-Ochoa EO, Blum ID, Granger JM, Yang J, Viswanathan MC, Aja S, Liu N, Antonescu CM, Florea LD, Conover Talbot C, Mohr D, Wagner KR, Regot S, Lovering RM, Wu MN, Cammarato AR, Schneider MF, Bever GS, Anderson ME. CaMKII oxidation is a performance-disease tradeoff in vertebrate evolution. J Mol Cell Cardiol 2020. [DOI: 10.1016/j.yjmcc.2019.11.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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15
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Howarth HM, Kadoor A, Salem R, Nicolds B, Adachi S, Kanaris A, Lovering RM, Brown JM, Shah SB. Nerve lengthening and subsequent end-to-end repair yield more favourable outcomes compared with autograft repair of rat sciatic nerve defects. J Tissue Eng Regen Med 2019; 13:2266-2278. [PMID: 31670904 DOI: 10.1002/term.2980] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/17/2019] [Accepted: 10/04/2019] [Indexed: 12/31/2022]
Abstract
Outcomes of end-to-end nerve repairs are more successful compared with outcomes of repairs bridged by nerve grafts. However, end-to-end repairs are not always possible for large nerve gaps, as excessive tension may cause catastrophic failure. In this study, we built on previous nerve-lengthening studies to test the hypotheses that gradual lengthening of the proximal stump across a large nerve gap enables an end-to-end repair and such a repair results in more favourable regenerative outcomes than autografts, which represent the gold standard in bridging nerve gaps. To test these, we compared structural and functional outcomes in Lewis rats after repair of sciatic nerve gaps using either autografts or a novel compact internal fixator device, which was used to lengthen proximal nerve stumps towards the distal stump over 2 weeks, prior to end-to-end repair. Twelve weeks after the initial injury, outcomes following nerve lengthening/end-to-end repair were either comparable or superior in every measure compared with repair by autografting. The sciatic functional index was not significantly different between groups at 12 weeks. However, we observed a reduced rate of contracture and corresponding significant increase in paw length in the lengthening group. This functional improvement was consistent with structural regeneration; axonal growth distal to the injury was denser and more evenly distributed compared with the autograft group, suggesting substantial regeneration into both tibial and peroneal branches of the sciatic nerve. Our findings show that end-to-end repairs following nerve lengthening are possible for large gaps and that this strategy may be superior to graft-based repairs.
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Affiliation(s)
- Holly M Howarth
- Department of Bioengineering, University of California, San Diego, La Jolla, CA
| | - Adarsh Kadoor
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA
| | - Rayeheh Salem
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA
| | - Brogan Nicolds
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA
| | - Stephanie Adachi
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA
| | - Achilles Kanaris
- Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD
| | - Justin M Brown
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA
| | - Sameer B Shah
- Department of Bioengineering, University of California, San Diego, La Jolla, CA.,Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, CA.,Research Service, VA San Diego Healthcare System, San Diego, CA
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16
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Muriel JM, O'Neill A, Kerr JP, Kleinhans-Welte E, Lovering RM, Bloch RJ. Keratin 18 is an integral part of the intermediate filament network in murine skeletal muscle. Am J Physiol Cell Physiol 2019; 318:C215-C224. [PMID: 31721615 DOI: 10.1152/ajpcell.00279.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Intermediate filaments (IFs) contribute to force transmission, cellular integrity, and signaling in skeletal muscle. We previously identified keratin 19 (Krt19) as a muscle IF protein. We now report the presence of a second type I muscle keratin, Krt18. Krt18 mRNA levels are about half those for Krt19 and only 1:1,000th those for desmin; the protein was nevertheless detectable in immunoblots. Muscle function, measured by maximal isometric force in vivo, was moderately compromised in Krt18-knockout (Krt18-KO) or dominant-negative mutant mice (Krt18 DN), but structure was unaltered. Exogenous Krt18, introduced by electroporation, was localized in a reticulum around the contractile apparatus in wild-type muscle and to a lesser extent in muscle lacking Krt19 or desmin or both proteins. Exogenous Krt19, which was either reticular or aggregated in controls, became reticular more frequently in Krt19-null than in Krt18-null, desmin-null, or double-null muscles. Desmin was assembled into the reticulum normally in all genotypes. Notably, all three IF proteins appeared in overlapping reticular structures. We assessed the effect of Krt18 on susceptibility to injury in vivo by electroporating siRNA into tibialis anterior (TA) muscles of control and Krt19-KO mice and testing 2 wk later. Results showed a 33% strength deficit (reduction in maximal torque after injury) compared with siRNA-treated controls. Conversely, electroporation of siRNA to Krt19 into Krt18-null TA yielded a strength deficit of 18% after injury compared with controls. Our results suggest that Krt18 plays a complementary role to Krt19 in skeletal muscle in both assembling keratin-based filaments and transducing contractile force.
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Affiliation(s)
- Joaquin M Muriel
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Andrea O'Neill
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jaclyn P Kerr
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Emily Kleinhans-Welte
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Robert J Bloch
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
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17
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Iyer SR, Shah SB, Ward CW, Stains JP, Spangenburg EE, Folker ES, Lovering RM. Differential YAP nuclear signaling in healthy and dystrophic skeletal muscle. Am J Physiol Cell Physiol 2019; 317:C48-C57. [PMID: 30995108 DOI: 10.1152/ajpcell.00432.2018] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mechanical forces regulate muscle development, hypertrophy, and homeostasis. Force-transmitting structures allow mechanotransduction at the sarcolemma, cytoskeleton, and nuclear envelope. There is growing evidence that Yes-associated protein (YAP) serves as a nuclear relay of mechanical signals and can induce a range of downstream signaling cascades. Dystrophin is a sarcolemma-associated protein, and its absence underlies the pathology in Duchenne muscular dystrophy. We tested the hypothesis that the absence of dystrophin in muscle would result in reduced YAP signaling in response to loading. Following in vivo contractile loading in muscles of healthy (wild-type; WT) mice and mice lacking dystrophin (mdx), we performed Western blots of whole and fractionated muscle homogenates to examine the ratio of phospho (cytoplasmic) YAP to total YAP and nuclear YAP, respectively. We show that in vivo contractile loading induced a robust increase in YAP expression and its nuclear localization in WT muscles. Surprisingly, in mdx muscles, active YAP expression was constitutively elevated and unresponsive to load. Results from qRT-PCR analysis support the hyperactivation of YAP in vivo in mdx muscles, as evidenced by increased gene expression of YAP downstream targets. In vitro assays of isolated myofibers plated on substrates with high stiffness showed YAP nuclear labeling for both genotypes, indicating functional YAP signaling in mdx muscles. We conclude that while YAP signaling can occur in the absence of dystrophin, dystrophic muscles have altered mechanotransduction, whereby constitutively active YAP results in a failure to respond to load, which could be attributed to the increased state of "pre-stress" with increased cytoskeletal and extracellular matrix stiffness.
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Affiliation(s)
- Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Sameer B Shah
- Department of Orthopaedic Surgery, University of California San Diego , La Jolla, California.,Department of Bioengineering, University of California San Diego , La Jolla, California
| | - Christopher W Ward
- Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Joseph P Stains
- Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Espen E Spangenburg
- Department of Physiology, East Carolina Diabetes and Obesity Institute, East Carolina University , Greenville, North Carolina
| | - Eric S Folker
- Department of Biology, Boston College , Chestnut Hill, Massachusetts
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland.,Department of Physiology, University of Maryland School of Medicine , Baltimore, Maryland
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18
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Tarpey MD, Valencia AP, Jackson KC, Amorese AJ, Balestrieri NP, Renegar RH, Pratt SJP, Ryan TE, McClung JM, Lovering RM, Spangenburg EE. Induced in vivo knockdown of the Brca1 gene in skeletal muscle results in skeletal muscle weakness. J Physiol 2019; 597:869-887. [PMID: 30556208 PMCID: PMC6355718 DOI: 10.1113/jp276863] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/19/2018] [Indexed: 12/22/2022] Open
Abstract
KEY POINTS Breast cancer 1 early onset gene codes for the DNA repair enzyme, breast cancer type 1 susceptibility protein (BRCA1). The gene is prone to mutations that cause a loss of protein function. BRCA1/Brca1 has recently been found to regulate several cellular pathways beyond DNA repair and is expressed in skeletal muscle. Skeletal muscle specific knockout of Brca1 in mice caused a loss of muscle quality, identifiable by reductions in muscle force production and mitochondrial respiratory capacity. Loss of muscle quality was associated with a shift in muscle phenotype and an accumulation of mitochondrial DNA mutations. These results demonstrate that BRCA1 is necessary for skeletal muscle function and that increased mitochondrial DNA mutations may represent a potential underlying mechanism. ABSTRACT Recent evidence suggests that the breast cancer 1 early onset gene (BRCA1) influences numerous peripheral tissues, including skeletal muscle. The present study aimed to determine whether induced-loss of the breast cancer type 1 susceptibility protein (Brca1) alters skeletal muscle function. We induced genetic ablation of exon 11 in the Brca1 gene specifically in the skeletal muscle of adult mice to generate skeletal muscle-specific Brca1 homozygote knockout (Brca1KOsmi ) mice. Brca1KOsmi exhibited kyphosis and decreased maximal isometric force in limb muscles compared to age-matched wild-type mice. Brca1KOsmi skeletal muscle shifted toward an oxidative muscle fibre type and, in parallel, increased myofibre size and reduced capillary numbers. Unexpectedly, myofibre bundle mitochondrial respiration was reduced, whereas contraction-induced lactate production was elevated in Brca1KOsmi muscle. Brca1KOsmi mice accumulated mitochondrial DNA mutations and exhibited an altered mitochondrial morphology characterized by distorted and enlarged mitochondria, and these were more susceptible to swelling. In summary, skeletal muscle-specific loss of Brca1 leads to a myopathy and mitochondriopathy characterized by reductions in skeletal muscle quality and a consequent kyphosis. Given the substantial impact of BRCA1 mutations on cancer development risk in humans, a parallel loss of BRCA1 function in patient skeletal muscle cells would potentially result in implications for human health.
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Affiliation(s)
- Michael D. Tarpey
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Ana P. Valencia
- School of Public HealthDepartment of KinesiologyUniversity of MarylandCollege ParkMDUSA
| | - Kathryn C. Jackson
- School of Public HealthDepartment of KinesiologyUniversity of MarylandCollege ParkMDUSA
| | - Adam J. Amorese
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | | | - Randall H. Renegar
- Department of Anatomy and Cell BiologyBrody School of Medicine at East Carolina UniversityGreenvilleNCUSA
| | - Stephen J. P. Pratt
- School of MedicineDepartment of OrthopedicsUniversity of MarylandBaltimoreMDUSA
| | - Terence E. Ryan
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Joseph M. McClung
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
- East Carolina Diabetes and Obesity InstituteBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
| | - Richard M. Lovering
- School of MedicineDepartment of OrthopedicsUniversity of MarylandBaltimoreMDUSA
| | - Espen E. Spangenburg
- Department of PhysiologyBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
- East Carolina Diabetes and Obesity InstituteBrody School of MedicineEast Carolina UniversityGreenvilleNCUSA
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19
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Harriot A, Coleman A, Iyer SR, Venagas C, Shi G, Lovering RM, Joca HC, Stains JP, Ward CW. Increased Microtubule Density and Level of Detyrosination Occur Coincident with Sarcomere Malformations in Diseased and Aging Skeletal Muscle. Biophys J 2019. [DOI: 10.1016/j.bpj.2018.11.2188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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20
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Gerlinger-Romero F, Addinsall AB, Lovering RM, Foletta VC, van der Poel C, Della-Gatta PA, Russell AP. Non-invasive Assessment of Dorsiflexor Muscle Function in Mice. J Vis Exp 2019. [PMID: 30735157 DOI: 10.3791/58696] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Assessment of skeletal muscle contractile function is an important measurement for both clinical and research purposes. Numerous conditions can negatively affect skeletal muscle. This can result in a loss of muscle mass (atrophy) and/or loss of muscle quality (reduced force per unit of muscle mass), both of which are prevalent in chronic disease, muscle-specific disease, immobilization, and aging (sarcopenia). Skeletal muscle function in animals can be evaluated by a range of different tests. All tests have limitations related to the physiological testing environment, and the selection of a specific test often depends on the nature of the experiments. Here, we describe an in vivo, non-invasive technique involving a helpful and easy assessment of force frequency-curve (FFC) in mice that can be performed on the same animal over time. This permits monitoring of disease progression and/or efficacy of a potential therapeutic treatment.
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Affiliation(s)
| | - Alex B Addinsall
- Centre for Molecular and Medical Research, School of Medicine, Deakin University
| | | | - Victoria C Foletta
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University
| | | | - Paul A Della-Gatta
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University
| | - Aaron P Russell
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University
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21
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Valencia AP, Lai JK, Iyer SR, Mistretta KL, Spangenburg EE, Davis DL, Lovering RM, Gilotra MN. Fatty Infiltration Is a Prognostic Marker of Muscle Function After Rotator Cuff Tear. Am J Sports Med 2018; 46:2161-2169. [PMID: 29750541 PMCID: PMC6397750 DOI: 10.1177/0363546518769267] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Massive rotator cuff tears (RCTs) begin as primary tendon injuries and cause a myriad of changes in the muscle, including atrophy, fatty infiltration (FI), and fibrosis. However, it is unclear which changes are most closely associated with muscle function. PURPOSE To determine if FI of the supraspinatus muscle after acute RCT relates to short-term changes in muscle function. STUDY DESIGN Controlled laboratory study. METHODS Unilateral RCTs were induced in female rabbits via tenotomy of the supraspinatus and infraspinatus. Maximal isometric force and rate of fatigue were measured in the supraspinatus in vivo at 6 and 12 weeks after tenotomy. Computed tomography scanning was performed, followed by histologic analysis of myofiber size, FI, and fibrosis. RESULTS Tenotomy resulted in supraspinatus weakness, reduced myofiber size, FI, and fibrosis, but no differences were evident between 6 and 12 weeks after tenotomy except for increased collagen content at 12 weeks. FI was a predictor of supraspinatus weakness and was strongly correlated to force, even after accounting for muscle cross-sectional area. While muscle atrophy accounted for the loss in force in tenotomized muscles with minimal FI, it did not account for the greater loss in force in tenotomized muscles with the most FI. Collagen content was not strongly correlated with maximal isometric force, even when normalized to muscle size. CONCLUSION After RCT, muscle atrophy results in the loss of contractile force from the supraspinatus, but exacerbated weakness is observed with increased FI. Therefore, the level of FI can help predict contractile function of torn rotator cuff muscles. CLINICAL RELEVANCE Markers to predict contractile function of RCTs will help determine the appropriate treatment to improve functional recovery after RCTs.
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Affiliation(s)
- Ana P. Valencia
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
- Department of Kinesiology, School of Public Health, University of Maryland, Baltimore, Maryland, USA
| | - Jim K. Lai
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Shama R. Iyer
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Katherine L. Mistretta
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Espen E. Spangenburg
- Department of Physiology, East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Derik L. Davis
- Department of Diagnostic Radiology and Nuclear Medicine, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Richard M. Lovering
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Mohit N. Gilotra
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
- Department of Orthopaedics, Baltimore Veteran Affairs Medical Center, Baltimore, Maryland, USA
- Address correspondence to Mohit N. Gilotra, MD, Department of Orthopaedics, School of Medicine and VA Maryland Health Care System, University of Maryland, AHB, Rm 540, 100 Penn St, Baltimore, MD 21201, USA ()
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22
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Iyer SR, Shah SB, Ward CW, Folker ES, Lovering RM. Yap as an Indicator of Nuclear Mechanotransduction in Mature Myofibers. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000536905.47203.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Lerner M, Iyer SR, Stains JP, Henn F, Bennett CH, Lovering RM. Use of Mesenchymal Stem Cells to Treat Muscle Strain Injuries. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000538229.94153.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Lovering RM, Iyer SR, Zhuo J, Roys S, Zhu W, Xu S. Assessment of Muscle Injury Using Diffusion Kurtosis MRI and1 H MRS. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000536484.25043.58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Gilbert-Honick J, Iyer SR, Somers SM, Lovering RM, Wagner K, Mao HQ, Grayson WL. Engineering functional and histological regeneration of vascularized skeletal muscle. Biomaterials 2018; 164:70-79. [PMID: 29499437 DOI: 10.1016/j.biomaterials.2018.02.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/01/2018] [Accepted: 02/02/2018] [Indexed: 12/18/2022]
Abstract
Tissue engineering strategies to treat patients with volumetric muscle loss (VML) aim to recover the structure and contractile function of lost muscle tissue. Here, we assessed the capacity of novel electrospun fibrin hydrogel scaffolds seeded with murine myoblasts to regenerate the structure and function of damaged muscle within VML defects to the mouse tibialis anterior muscle. The electrospun fibrin scaffolds provide pro-myogenic alignment and stiffness cues, myomimetic hierarchical structure, suturability, and scale-up capabilities. Myoblast-seeded scaffolds enabled remarkable muscle regeneration with high myofiber and vascular densities after 2 and 4 weeks, mimicking that of native skeletal muscle, while acellular scaffolds lacked muscle regeneration. Both myoblast-seeded and acellular scaffolds fully recovered muscle contractile function to uninjured values after 2 and 4 weeks. Electrospun scaffolds pre-vascularized with co-cultured human endothelial cells and human adipose-derived stem cells implanted into VML defects for 2 weeks anastomosed with host vasculature and were perfused with host red blood cells. These data demonstrate the significant potential of electrospun fibrin scaffolds seeded with myoblasts to fully regenerate the structure and function of volumetric muscle defects and these scaffolds offer a promising treatment option for patients with VML.
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Affiliation(s)
- Jordana Gilbert-Honick
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Sarah M Somers
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Kathryn Wagner
- The Hugo W. Moser Research Institute, Kennedy Krieger Institute, Baltimore, MD, 21205, USA; Graduate Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA; Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Hai-Quan Mao
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Materials Science & Engineering, Johns Hopkins University School of Engineering, Baltimore, MD, 21218, USA; Institute for NanoBioTechnology (INBT), Johns Hopkins University School of Engineering, Baltimore, MD 21218, USA
| | - Warren L Grayson
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Materials Science & Engineering, Johns Hopkins University School of Engineering, Baltimore, MD, 21218, USA; Institute for NanoBioTechnology (INBT), Johns Hopkins University School of Engineering, Baltimore, MD 21218, USA.
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26
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Jackson KC, Tarpey MD, Valencia AP, Iñigo MR, Pratt SJ, Patteson DJ, McClung JM, Lovering RM, Thomson DM, Spangenburg EE. Induced Cre-mediated knockdown of Brca1 in skeletal muscle reduces mitochondrial respiration and prevents glucose intolerance in adult mice on a high-fat diet. FASEB J 2018; 32:3070-3084. [PMID: 29401626 DOI: 10.1096/fj.201700464r] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The breast cancer type 1 susceptibility protein (Brca1) is a regulator of DNA repair in mammary gland cells; however, recent cell culture evidence suggests that Brca1 influences other processes, including those in nonmammary cells. In this study, we sought to determine whether Brca1 is necessary for metabolic regulation of skeletal muscle using a novel in vivo mouse model. We developed an inducible skeletal muscle-specific Brca1knockout (BRCA1KOsmi) model to test whether Brca1 expression is necessary for maintenance of metabolic function of skeletal muscle when exposed to a high-fat diet (HFD). Our data demonstrated that deletion of Brca1 prevented HFD-induced alterations in glucose and insulin tolerance. Irrespective of diet, BRCA1KOsmi mice exhibited significantly lower ADP-stimulated complex I mitochondrial respiration rates compared to age-matched wild-type (WT) mice. The data show that Brca1 has the ability to localize to the mitochondria in skeletal muscle and that BRCA1KOsmi mice exhibit higher whole-body CO2 production, respiratory exchange ratio, and energy expenditure, compared with the WT mice. Our results demonstrate that loss of Brca1 in skeletal muscle leads to dysregulated metabolic function, characterized by decreased mitochondrial respiration. Thus, any condition that results in loss of Brca1 function could induce metabolic imbalance in skeletal muscle.-Jackson, K. C., Tarpey, M. D., Valencia, A. P., Iñigo, M. R., Pratt, S. J., Patteson, D. J., McClung, J. M., Lovering, R. M., Thomson, D. M., Spangenburg, E. E. Induced Cre-mediated knockdown of Brca1 in skeletal muscle reduces mitochondrial respiration and prevents glucose intolerance in adult mice on a high-fat diet.
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Affiliation(s)
- Kathryn C Jackson
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland, USA
| | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Ana P Valencia
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland, USA
| | - Melissa R Iñigo
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland, USA.,Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Stephen J Pratt
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Daniel J Patteson
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; and
| | - Richard M Lovering
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - David M Thomson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah, USA
| | - Espen E Spangenburg
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland, USA.,Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA.,East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, North Carolina, USA; and
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Abstract
Duchenne muscular dystrophy (DMD), caused by the absence of the protein dystrophin, is characterized as a neuromuscular disease in which muscle weakness, increased susceptibility to muscle injury, and inadequate repair appear to underlie the pathology. Considerable attention has been dedicated to studying muscle fiber damage, but there is little information to determine if damage from contraction-induced injury also occurs at or near the nerve terminal axon. Interestingly, both human patients and the mouse model for DMD (the mdx mouse) present fragmented neuromuscular junction (NMJ) morphology. Studies of mdx mice have revealed presynaptic and postsynaptic abnormalities, nerve terminal discontinuity, as well as increased susceptibility of the NMJ to contraction-induced injury with corresponding functional changes in neuromuscular transmission and nerve-evoked electromyography. Focusing on the NMJ as a contributor to functional deficits in the muscle represents a paradigm shift from the more prevalent myocentric perspectives. Further studies are needed to determine the extent to which the nerve-muscle interaction is disrupted in DMD and the role of the NMJ in the dystrophic progression. This chapter lists the tools needed for nerve terminal and NMJ structural analysis using fluorescence imaging, and provides a step-by-step outline for how to stain, image, and analyze the NMJ in skeletal muscle, with specific attention to mdx muscle.
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Affiliation(s)
- Stephen J P Pratt
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore School of Medicine, Baltimore, MD, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland, Baltimore School of Medicine, 100 Penn St., AHB, Room 540, Baltimore, MD, 21201, USA
| | - Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
- Research Division, Veterans Administration San Diego Healthcare System, San Diego, CA, 92121, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland, Baltimore School of Medicine, 100 Penn St., AHB, Room 540, Baltimore, MD, 21201, USA.
- Department of Physiology, University of Maryland, Baltimore School of Medicine, Baltimore, MD, USA.
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Ryu D, Zhang H, Ropelle ER, Sorrentino V, Mázala DAG, Mouchiroud L, Marshall PL, Campbell MD, Ali AS, Knowels GM, Bellemin S, Iyer SR, Wang X, Gariani K, Sauve AA, Cantó C, Conley KE, Walter L, Lovering RM, Chin ER, Jasmin BJ, Marcinek DJ, Menzies KJ, Auwerx J. NAD+ repletion improves muscle function in muscular dystrophy and counters global PARylation. Sci Transl Med 2017; 8:361ra139. [PMID: 27798264 DOI: 10.1126/scitranslmed.aaf5504] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 09/12/2016] [Indexed: 12/25/2022]
Abstract
Neuromuscular diseases are often caused by inherited mutations that lead to progressive skeletal muscle weakness and degeneration. In diverse populations of normal healthy mice, we observed correlations between the abundance of mRNA transcripts related to mitochondrial biogenesis, the dystrophin-sarcoglycan complex, and nicotinamide adenine dinucleotide (NAD+) synthesis, consistent with a potential role for the essential cofactor NAD+ in protecting muscle from metabolic and structural degeneration. Furthermore, the skeletal muscle transcriptomes of patients with Duchene's muscular dystrophy (DMD) and other muscle diseases were enriched for various poly[adenosine 5'-diphosphate (ADP)-ribose] polymerases (PARPs) and for nicotinamide N-methyltransferase (NNMT), enzymes that are major consumers of NAD+ and are involved in pleiotropic events, including inflammation. In the mdx mouse model of DMD, we observed significant reductions in muscle NAD+ levels, concurrent increases in PARP activity, and reduced expression of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD+ biosynthesis. Replenishing NAD+ stores with dietary nicotinamide riboside supplementation improved muscle function and heart pathology in mdx and mdx/Utr-/- mice and reversed pathology in Caenorhabditis elegans models of DMD. The effects of NAD+ repletion in mdx mice relied on the improvement in mitochondrial function and structural protein expression (α-dystrobrevin and δ-sarcoglycan) and on the reductions in general poly(ADP)-ribosylation, inflammation, and fibrosis. In combination, these studies suggest that the replenishment of NAD+ may benefit patients with muscular dystrophies or other neuromuscular degenerative conditions characterized by the PARP/NNMT gene expression signatures.
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Affiliation(s)
- Dongryeol Ryu
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Hongbo Zhang
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Eduardo R Ropelle
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.,Laboratory of Molecular Biology of Exercise, School of Applied Science, University of Campinas, CEP 13484-350 Limeira, São Paulo, Brazil
| | - Vincenzo Sorrentino
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Davi A G Mázala
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD 20742, USA
| | - Laurent Mouchiroud
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Philip L Marshall
- Interdisciplinary School of Health Sciences, University of Ottawa Brain and Mind Research Institute and Centre for Neuromuscular Disease, Ottawa, Ontario K1H 8M5, Canada
| | - Matthew D Campbell
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Amir Safi Ali
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Gary M Knowels
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Stéphanie Bellemin
- Centre de Génétique et de Physiologie Moléculaires et Cellulaires, Université Claude Bernard Lyon 1, CNRS UMR 5534, 69622 Villeurbanne, France
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Xu Wang
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Karim Gariani
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Anthony A Sauve
- Department of Pharmacology, Weill Cornell Medical School, New York, NY 10065, USA
| | - Carles Cantó
- Nestlé Institute of Health Sciences, 1015 Lausanne, Switzerland
| | - Kevin E Conley
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Ludivine Walter
- Centre de Génétique et de Physiologie Moléculaires et Cellulaires, Université Claude Bernard Lyon 1, CNRS UMR 5534, 69622 Villeurbanne, France
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Eva R Chin
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, MD 20742, USA
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - David J Marcinek
- Department of Radiology, University of Washington, Seattle, WA 98195, USA
| | - Keir J Menzies
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland. .,Interdisciplinary School of Health Sciences, University of Ottawa Brain and Mind Research Institute and Centre for Neuromuscular Disease, Ottawa, Ontario K1H 8M5, Canada
| | - Johan Auwerx
- Laboratory of Integrative and Systems Physiology, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
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Valencia AP, Iyer SR, Spangenburg EE, Gilotra MN, Lovering RM. Impaired contractile function of the supraspinatus in the acute period following a rotator cuff tear. BMC Musculoskelet Disord 2017; 18:436. [PMID: 29121906 PMCID: PMC5679320 DOI: 10.1186/s12891-017-1789-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 10/26/2017] [Indexed: 01/16/2023] Open
Abstract
Background Rotator cuff (RTC) tears are a common clinical problem resulting in adverse changes to the muscle, but there is limited information comparing histopathology to contractile function. This study assessed supraspinatus force and susceptibility to injury in the rat model of RTC tear, and compared these functional changes to histopathology of the muscle. Methods Unilateral RTC tears were induced in male rats via tenotomy of the supraspinatus and infraspinatus. Maximal tetanic force and susceptibility to injury of the supraspinatus muscle were measured in vivo at day 2 and day 15 after tenotomy. Supraspinatus muscles were weighed and harvested for histologic analysis of the neuromuscular junction (NMJ), intramuscular lipid, and collagen. Results Tenotomy resulted in eventual atrophy and weakness. Despite no loss in muscle mass at day 2 there was a 30% reduction in contractile force, and a decrease in NMJ continuity and size. Reduced force persisted at day 15, a time point when muscle atrophy was evident but NMJ morphology was restored. At day 15, torn muscles had decreased collagen-packing density and were also more susceptible to contraction-induced injury. Conclusion Muscle size and histopathology are not direct indicators of overall RTC contractile health. Changes in NMJ morphology and collagen organization were associated with changes in contractile function and thus may play a role in response to injury. Although our findings are limited to the acute phase after a RTC tear, the most salient finding is that RTC tenotomy results in increased susceptibility to injury of the supraspinatus.
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Affiliation(s)
- Ana P Valencia
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Rm 540, 100 Penn St., Baltimore, MD, 21201, USA.,Department of Kinesiology, University of Maryland School of Public Health, College Park, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Rm 540, 100 Penn St., Baltimore, MD, 21201, USA
| | - Espen E Spangenburg
- Department of Physiology, East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, USA
| | - Mohit N Gilotra
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Rm 540, 100 Penn St., Baltimore, MD, 21201, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Rm 540, 100 Penn St., Baltimore, MD, 21201, USA.
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Sanchez B, Iyer SR, Li J, Kapur K, Xu S, Rutkove SB, Lovering RM. Non-invasive assessment of muscle injury in healthy and dystrophic animals with electrical impedance myography. Muscle Nerve 2017; 56:E85-E94. [PMID: 28056487 DOI: 10.1002/mus.25559] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/30/2016] [Accepted: 01/04/2017] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Dystrophic muscle is particularly susceptible to eccentric contraction-induced injury. We tested the hypothesis that electrical impedance myography (EIM) can detect injury induced by maximal-force lengthening contractions. METHODS We induced injury in the quadriceps of wild-type (WT) and dystrophic (mdx) mice with eccentric contractions using an established model. RESULTS mdx quadriceps had significantly greater losses in peak twitch and tetany compared with losses in WT quadriceps. Injured muscle showed a significant increase in EIM characteristic frequency in both WT (177 ± 7.7%) and mdx (167 ± 7.8%) quadriceps. EIM also revealed decreased extracellular resistance for both WT and mdx quadriceps after injury. DISCUSSION Our results show overall agreement between muscle function and EIM measurements of injured muscle, indicating that EIM is a viable tool to assess injury in dystrophic muscle. Muscle Nerve 56: E85-E94, 2017.
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Affiliation(s)
- Benjamin Sanchez
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Room 540, 100 Penn Street, Baltimore, Maryland, 21201, USA
| | - Jia Li
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Kush Kapur
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.,Boston Children's Hospital, Boston, Massachusetts, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Seward B Rutkove
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, AHB, Room 540, 100 Penn Street, Baltimore, Maryland, 21201, USA
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31
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Love JM, Bober BG, Orozco E, White AT, Bremner SN, Lovering RM, Schenk S, Shah SB. mTOR regulates peripheral nerve response to tensile strain. J Neurophysiol 2017; 117:2075-2084. [PMID: 28250148 PMCID: PMC5434482 DOI: 10.1152/jn.00257.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 02/09/2017] [Accepted: 02/25/2017] [Indexed: 01/26/2023] Open
Abstract
While excessive tensile strain can be detrimental to nerve function, strain can be a positive regulator of neuronal outgrowth. We used an in vivo rat model of sciatic nerve strain to investigate signaling mechanisms underlying peripheral nerve response to deformation. Nerves were deformed by 11% and did not demonstrate deficits in compound action potential latency or amplitude during or after 6 h of strain. As revealed by Western blotting, application of strain resulted in significant upregulation of mammalian target of rapamycin (mTOR) and S6 signaling in nerves, increased myelin basic protein (MBP) and β-actin levels, and increased phosphorylation of neurofilament subunit H (NF-H) compared with unstrained (sham) contralateral nerves (P < 0.05 for all comparisons, paired two-tailed t-test). Strain did not alter neuron-specific β3-tubulin or overall nerve tubulin levels compared with unstrained controls. Systemic rapamycin treatment, thought to selectively target mTOR complex 1 (mTORC1), suppressed mTOR/S6 signaling, reduced levels of MBP and overall tubulin, and decreased NF-H phosphorylation in nerves strained for 6 h, revealing a role for mTOR in increasing MBP expression and NF-H phosphorylation, and maintaining tubulin levels. Consistent with stretch-induced increases in MBP, immunolabeling revealed increased S6 signaling in Schwann cells of stretched nerves compared with unstretched nerves. In addition, application of strain to cultured adult dorsal root ganglion neurons showed an increase in axonal protein synthesis based on a puromycin incorporation assay, suggesting that neuronal translational pathways also respond to strain. This work has important implications for understanding mechanisms underlying nerve response to strain during development and regeneration.NEW & NOTEWORTHY Peripheral nerves experience tensile strain (stretch) during development and movement. Excessive strain impairs neuronal function, but moderate strains are accommodated by nerves and can promote neuronal growth; mechanisms underlying these phenomena are not well understood. We demonstrated that levels of several structural proteins increase following physiological levels of nerve strain and that expression of a subset of these proteins is regulated by mTOR. Our work has important implications for understanding nerve development and strain-based regenerative strategies.
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Affiliation(s)
- James M Love
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Brian G Bober
- Department of Bioengineering, University of California-San Diego, La Jolla, California
| | - Elisabeth Orozco
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Amanda T White
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California
| | - Shannon N Bremner
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Simon Schenk
- Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California
| | - Sameer B Shah
- Department of Bioengineering, University of California-San Diego, La Jolla, California; .,Department of Orthopaedic Surgery, University of California-San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
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Iyer SR, Xu S, Stains JP, Bennett CH, Lovering RM. Superparamagnetic Iron Oxide Nanoparticles in Musculoskeletal Biology. Tissue Eng Part B Rev 2017; 23:373-385. [PMID: 27998240 DOI: 10.1089/ten.teb.2016.0437] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The use of platelet-rich plasma and mesenchymal stem cells has garnered much attention in orthopedic medicine, focusing on the biological aspects of cell function. However, shortly after systemic delivery, or even a local injection, few of the transplanted stem cells or platelets remain at the target site. Improvement in delivery, and the ability to track and monitor injected cells, would greatly improve clinical translation. Nanoparticles can effectively and quickly label most cells in vitro, and evidence to date suggests such labeling does not compromise the proliferation or differentiation of cells. A specific type of nanoparticle, the superparamagnetic iron oxide nanoparticle (SPION), is already employed as a magnetic resonance imaging (MRI) contrast agent. SPIONs can be coupled with cells or bioactive molecules (antibodies, proteins, drugs, etc.) to form an injectable complex for in vivo use. The biocompatibility, magnetic properties, small size, and custom-made surface coatings also enable SPIONs to be used for delivering and monitoring of small molecules, drugs, and cells, specifically to muscle, bone, or cartilage. Because SPIONs consist of cores made of iron oxides, targeting of SPIONs to a specific muscle, bone, or joint in the body can be enhanced with the help of applied gradient magnetic fields. Moreover, MRI has a high sensitivity to SPIONs and can be used for noninvasive determination of successful delivery and monitoring distribution in vivo. Gaps remain in understanding how the physical and chemical properties of nanomaterials affect biological systems. Nonetheless, SPIONs hold great promise for regenerative medicine, and progress is being made rapidly toward clinical applications in orthopedic medicine.
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Affiliation(s)
- Shama R Iyer
- 1 Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Su Xu
- 2 Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine , Baltimore, Maryland
| | - Joseph P Stains
- 1 Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Craig H Bennett
- 1 Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland
| | - Richard M Lovering
- 1 Department of Orthopaedics, University of Maryland School of Medicine , Baltimore, Maryland.,3 Department of Physiology, University of Maryland School of Medicine , Baltimore, Maryland
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Iyer SR, Shah SB, Valencia AP, Schneider MF, Hernández-Ochoa EO, Stains JP, Blemker SS, Lovering RM. Altered nuclear dynamics in MDX myofibers. J Appl Physiol (1985) 2016; 122:470-481. [PMID: 27979987 DOI: 10.1152/japplphysiol.00857.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/02/2016] [Accepted: 12/06/2016] [Indexed: 01/17/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a genetic disorder in which the absence of dystrophin leads to progressive muscle degeneration and weakness. Although the genetic basis is known, the pathophysiology of dystrophic skeletal muscle remains unclear. We examined nuclear movement in wild-type (WT) and muscular dystrophy mouse model for DMD (MDX) (dystrophin-null) mouse myofibers. We also examined expression of proteins in the linkers of nucleoskeleton and cytoskeleton (LINC) complex, as well as nuclear transcriptional activity via histone H3 acetylation and polyadenylate-binding nuclear protein-1. Because movement of nuclei is not only LINC dependent but also microtubule dependent, we analyzed microtubule density and organization in WT and MDX myofibers, including the application of a unique 3D tool to assess microtubule core structure. Nuclei in MDX myofibers were more mobile than in WT myofibers for both distance traveled and velocity. MDX muscle shows reduced expression and labeling intensity of nesprin-1, a LINC protein that attaches the nucleus to the microtubule and actin cytoskeleton. MDX nuclei also showed altered transcriptional activity. Previous studies established that microtubule structure at the cortex is disrupted in MDX myofibers; our analyses extend these findings by showing that microtubule structure in the core is also disrupted. In addition, we studied malformed MDX myofibers to better understand the role of altered myofiber morphology vs. microtubule architecture in the underlying susceptibility to injury seen in dystrophic muscles. We incorporated morphological and microtubule architectural concepts into a simplified finite element mathematical model of myofiber mechanics, which suggests a greater contribution of myofiber morphology than microtubule structure to muscle biomechanical performance.NEW & NOTEWORTHY Microtubules provide the means for nuclear movement but show altered organization in the muscular dystrophy mouse model (MDX) (dystrophin-null) muscle. Here, MDX myofibers show increased nuclear movement, altered transcriptional activity, and altered linkers of nucleoskeleton and cytoskeleton complex expression compared with healthy myofibers. Microtubule architecture was incorporated in finite element modeling of passive stretch, revealing a role of fiber malformation, commonly found in MDX muscle. The results suggest that alterations in microtubule architecture in MDX muscle affect nuclear movement, which is essential for muscle function.
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Affiliation(s)
- Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California San Diego, La Jolla, California
| | - Ana P Valencia
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Martin F Schneider
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Erick O Hernández-Ochoa
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Joseph P Stains
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Silvia S Blemker
- Department of Biomedical Engineering and Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia; and
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; .,Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
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Lyons JS, Iyer SR, Lovering RM, Ward CW, Stains JP. Novel multi-functional fluid flow device for studying cellular mechanotransduction. J Biomech 2016; 49:4173-4179. [PMID: 27887728 DOI: 10.1016/j.jbiomech.2016.11.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 11/09/2016] [Accepted: 11/12/2016] [Indexed: 11/15/2022]
Abstract
Cells respond to their mechanical environment by initiating multiple mechanotransduction signaling pathways. Defects in mechanotransduction have been implicated in a number of pathologies; thus, there is need for convenient and efficient methods for studying the mechanisms underlying these processes. A widely used and accepted technique for mechanically stimulating cells in culture is the introduction of fluid flow on cell monolayers. Here, we describe a novel, multifunctional fluid flow device for exposing cells to fluid flow in culture. This device integrates with common lab equipment including routine cell culture plates and peristaltic pumps. Further, it allows the fluid flow treated cells to be examined with outcomes at the cell and molecular level. We validated the device using the biologic response of cultured UMR-106 osteoblast-like cells in comparison to a commercially available system of laminar sheer stress to track live cell calcium influx in response to fluid flow. In addition, we demonstrate the fluid flow-dependent activation of phospho-ERK in these cells, consistent with the findings in other fluid flow devices. This device provides a low cost, multi-functional alternative to currently available systems, while still providing the ability to generate physiologically relevant conditions for studying processes involved in mechanotransduction in vitro.
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Affiliation(s)
- James S Lyons
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | | | - Joseph P Stains
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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35
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Valencia AP, Iyer SR, Gilotra MN, Lovering RM. Effects of Rotator Cuff Tear on Supraspinatus Muscle Contractility. Med Sci Sports Exerc 2016. [DOI: 10.1249/01.mss.0000486766.03871.63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Iyer S, Gupta A, Valencia AP, Stains JP, Lovering RM. Eccentric Contractions Promote Osteoclast Activity in the Tibia. Med Sci Sports Exerc 2016. [DOI: 10.1249/01.mss.0000485929.66262.ea] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hernández-Ochoa EO, Vanegas C, Iyer SR, Lovering RM, Schneider MF. Alternating bipolar field stimulation identifies muscle fibers with defective excitability but maintained local Ca(2+) signals and contraction. Skelet Muscle 2016; 6:6. [PMID: 26855765 PMCID: PMC4743112 DOI: 10.1186/s13395-016-0076-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/05/2016] [Indexed: 11/25/2022] Open
Abstract
Background Most cultured enzymatically dissociated adult myofibers exhibit spatially uniform (UNI) contractile responses and Ca2+ transients over the entire myofiber in response to electric field stimuli of either polarity applied via bipolar electrodes. However, some myofibers only exhibit contraction and Ca2+ transients at alternating (ALT) ends in response to alternating polarity field stimulation. Here, we present for the first time the methodology for identification of ALT myofibers in primary cultures and isolated muscles, as well as a study of their electrophysiological properties. Results We used high-speed confocal microscopic Ca2+ imaging, electric field stimulation, microelectrode recordings, immunostaining, and confocal microscopy to characterize the properties of action potential-induced Ca2+ transients, contractility, resting membrane potential, and staining of T-tubule voltage-gated Na+ channel distribution applied to cultured adult myofibers. Here, we show for the first time, with high temporal and spatial resolution, that normal control myofibers with UNI responses can be converted to ALT response myofibers by TTX addition or by removal of Na+ from the bathing medium, with reappearance of the UNI response on return of Na+. Our results suggest disrupted excitability as the cause of ALT behavior and indicate that the ALT response is due to local depolarization-induced Ca2+ release, whereas the UNI response is triggered by action potential propagation over the entire myofiber. Consistent with this interpretation, local depolarizing monopolar stimuli give uniform (propagated) responses in UNI myofibers, but only local responses at the electrode in ALT myofibers. The ALT responses in electrically inexcitable myofibers are consistent with expectations of current spread between bipolar stimulating electrodes, entering (hyperpolarizing) one end of a myofiber and leaving (depolarizing) the other end of the myofiber. ALT responses were also detected in some myofibers within intact isolated whole muscles from wild-type and MDX mice, demonstrating that ALT responses can be present before enzymatic dissociation. Conclusions We suggest that checking for ALT myofiber responsiveness by looking at the end of a myofiber during alternating polarity stimuli provides a test for compromised excitability of myofibers, and could be used to identify inexcitable, damaged or diseased myofibers by ALT behavior in healthy and diseased muscle. Electronic supplementary material The online version of this article (doi:10.1186/s13395-016-0076-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Erick O Hernández-Ochoa
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Maryland, Baltimore, 108 N. Greene Street, Baltimore, MD 21201 USA
| | - Camilo Vanegas
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Maryland, Baltimore, 108 N. Greene Street, Baltimore, MD 21201 USA
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201 USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201 USA
| | - Martin F Schneider
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Maryland, Baltimore, 108 N. Greene Street, Baltimore, MD 21201 USA
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Hernández-Ochoa EO, Pratt SJP, Lovering RM, Schneider MF. Critical Role of Intracellular RyR1 Calcium Release Channels in Skeletal Muscle Function and Disease. Front Physiol 2016; 6:420. [PMID: 26793121 PMCID: PMC4709859 DOI: 10.3389/fphys.2015.00420] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 12/21/2015] [Indexed: 01/25/2023] Open
Abstract
The skeletal muscle Ca2+ release channel, also known as ryanodine receptor type 1 (RyR1), is the largest ion channel protein known and is crucial for effective skeletal muscle contractile activation. RyR1 function is controlled by Cav1.1, a voltage gated Ca2+ channel that works mainly as a voltage sensor for RyR1 activity during skeletal muscle contraction and is also fine-tuned by Ca2+, several intracellular compounds (e.g., ATP), and modulatory proteins (e.g., calmodulin). Dominant and recessive mutations in RyR1, as well as acquired channel alterations, are the underlying cause of various skeletal muscle diseases. The aim of this mini review is to summarize several current aspects of RyR1 function, structure, regulation, and to describe the most common diseases caused by hereditary or acquired RyR1 malfunction.
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Affiliation(s)
- Erick O Hernández-Ochoa
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine Baltimore, MD, USA
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA
| | - Martin F Schneider
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine Baltimore, MD, USA
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Valencia AP, Iyer SR, Pratt SJP, Gilotra MN, Lovering RM. A method to test contractility of the supraspinatus muscle in mouse, rat, and rabbit. J Appl Physiol (1985) 2015; 120:310-7. [PMID: 26586911 DOI: 10.1152/japplphysiol.00788.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/17/2015] [Indexed: 01/06/2023] Open
Abstract
The rotator cuff (RTC) muscles not only generate movement but also provide important shoulder joint stability. RTC tears, particularly in the supraspinatus muscle, are a common clinical problem. Despite some biological healing after RTC repair, persistent problems include poor functional outcomes with high retear rates after surgical repair. Animal models allow further exploration of the sequela of RTC injury such as fibrosis, inflammation, and fatty infiltration, but there are few options regarding contractility for mouse, rat, and rabbit. Histological findings can provide a "direct measure" of damage, but the most comprehensive measure of the overall health of the muscle is contractile force. However, information regarding normal supraspinatus size and contractile function is scarce. Animal models provide the means to compare muscle histology, imaging, and contractility within individual muscles in various models of injury and disease, but to date, most testing of animal contractile force has been limited primarily to hindlimb muscles. Here, we describe an in vivo method to assess contractility of the supraspinatus muscle and describe differences in methods and representative outcomes for mouse, rat, and rabbit.
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Affiliation(s)
- Ana P Valencia
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and Department of Kinesiology, University of Maryland School of Public Health, College Park, Maryland
| | - Shama R Iyer
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Mohit N Gilotra
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland; and
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Pratt SJP, Valencia AP, Le GK, Shah SB, Lovering RM. Pre- and postsynaptic changes in the neuromuscular junction in dystrophic mice. Front Physiol 2015; 6:252. [PMID: 26441672 PMCID: PMC4563167 DOI: 10.3389/fphys.2015.00252] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/28/2015] [Indexed: 01/05/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a devastating neuromuscular disease in which weakness, increased susceptibility to muscle injury, and inadequate repair appear to underlie the pathology. While most attention has focused within the muscle fiber, we recently demonstrated in mdx mice (murine model for DMD) significant morphologic alterations at the motor endplate of the neuromuscular junction (NMJ) and corresponding NMJ transmission failure after injury. Here we extend these initial observations at the motor endplate to gain insight into the pre- vs. postsynaptic morphology, as well as the subsynaptic nuclei in healthy (WT) vs. mdx mice. We quantified the discontinuity and branching of the terminal nerve in adult mice. We report mdx- and age-dependent changes for discontinuity and an increase in branching when compared to WT. To examine mdx- and age-dependent changes in the relative localization of pre- and postsynaptic structures, we calculated NMJ occupancy, defined as the ratio of the footprint occupied by presynaptic vesicles vs. that of the underlying motor endplate. The normally congruent coupling between presynaptic and postsynaptic morphology was altered in mdx mice, independent of age. Finally we found an almost two-fold increase in the number of nuclei and an increase in density (nuclei/area) underlying the NMJ. These outcomes suggest substantial remodeling of the NMJ during dystrophic progression. This remodeling reflects plasticity in both pre- and postsynaptic contributors to NMJ structure, and thus perhaps also NM transmission and muscle function.
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Affiliation(s)
- Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA
| | - Ana P Valencia
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA ; Department of Kinesiology, University of Maryland School of Public Health College Park, MD, USA
| | - Gloribel K Le
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA
| | - Sameer B Shah
- Departments of Orthopaedic Surgery and Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine Baltimore, MD, USA
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41
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Xu S, Shi D, Pratt SJP, Zhu W, Marshall A, Lovering RM. Abnormalities in brain structure and biochemistry associated with mdx mice measured by in vivo MRI and high resolution localized (1)H MRS. Neuromuscul Disord 2015; 25:764-72. [PMID: 26236031 DOI: 10.1016/j.nmd.2015.07.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 06/21/2015] [Accepted: 07/06/2015] [Indexed: 01/16/2023]
Abstract
Duchenne muscular dystrophy (DMD), an X-linked disorder caused by the lack of dystrophin, is characterized by the progressive wasting of skeletal muscles. To date, what is known about dystrophin function is derived from studies of dystrophin-deficient animals, with the most common model being the mdx mouse. Most studies on patients with DMD and in mdx mice have focused on skeletal muscle and the development of therapies to reverse, or at least slow, the severe muscle wasting and progressive degeneration. However, dystrophin is also expressed in the CNS. Both mdx mice and patients with DMD can have cognitive and behavioral changes, but studies in the dystrophic brain are limited. We examined the brain structure and metabolites of mature wild type (WT) and mdx mice using magnetic resonance imaging and spectroscopy (MRI/MRS). Both structural and metabolic alterations were observed in the mdx brain. Enlarged lateral ventricles were detected in mdx mice when compared to WT. Diffusion tensor imaging (DTI) revealed elevations in diffusion diffusivities in the prefrontal cortex and a reduction of fractional anisotropy in the hippocampus. Metabolic changes included elevations in phosphocholine and glutathione, and a reduction in γ-aminobutyric acid in the hippocampus. In addition, an elevation in taurine was observed in the prefrontal cortex. Such findings indicate a regional structural change, altered cellular antioxidant defenses, a dysfunction of GABAergic neurotransmission, and a perturbed osmoregulation in the brain lacking dystrophin.
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Affiliation(s)
- Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Da Shi
- Department of Diagnostic Radiology and Nuclear Medicine, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Stephen J P Pratt
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Wenjun Zhu
- Department of Diagnostic Radiology and Nuclear Medicine, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Andrew Marshall
- Department of Diagnostic Radiology and Nuclear Medicine, School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Richard M Lovering
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, MD, USA.
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Roche JA, Tulapurkar ME, Mueller AL, van Rooijen N, Hasday JD, Lovering RM, Bloch RJ. Myofiber damage precedes macrophage infiltration after in vivo injury in dysferlin-deficient A/J mouse skeletal muscle. Am J Pathol 2015; 185:1686-98. [PMID: 25920768 PMCID: PMC4450316 DOI: 10.1016/j.ajpath.2015.02.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 12/31/2014] [Accepted: 02/12/2015] [Indexed: 12/16/2022]
Abstract
Mutations in the dysferlin gene (DYSF) lead to human muscular dystrophies known as dysferlinopathies. The dysferlin-deficient A/J mouse develops a mild myopathy after 6 months of age, and when younger models the subclinical phase of the human disease. We subjected the tibialis anterior muscle of 3- to 4-month-old A/J mice to in vivo large-strain injury (LSI) from lengthening contractions and studied the progression of torque loss, myofiber damage, and inflammation afterward. We report that myofiber damage in A/J mice occurs before inflammatory cell infiltration. Peak edema and inflammation, monitored by magnetic resonance imaging and by immunofluorescence labeling of neutrophils and macrophages, respectively, develop 24 to 72 hours after LSI, well after the appearance of damaged myofibers. Cytokine profiles 72 hours after injury are consistent with extensive macrophage infiltration. Dysferlin-sufficient A/WySnJ mice show much less myofiber damage and inflammation and lesser cytokine levels after LSI than do A/J mice. Partial suppression of macrophage infiltration by systemic administration of clodronate-incorporated liposomes fails to suppress LSI-induced damage or to accelerate torque recovery in A/J mice. The findings from our studies suggest that, although macrophage infiltration is prominent in dysferlin-deficient A/J muscle after LSI, it is the consequence and not the cause of progressive myofiber damage.
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Affiliation(s)
- Joseph A Roche
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland.
| | - Mohan E Tulapurkar
- Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Amber L Mueller
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Nico van Rooijen
- Clodronateliposomes.com, Amsterdam, the Netherlands; Department of Molecular Cell Biology, Faculty of Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Jeffrey D Hasday
- Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Richard M Lovering
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Robert J Bloch
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland
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43
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Hernández-Ochoa EO, Pratt SJP, Garcia-Pelagio KP, Schneider MF, Lovering RM. Disruption of action potential and calcium signaling properties in malformed myofibers from dystrophin-deficient mice. Physiol Rep 2015; 3:3/4/e12366. [PMID: 25907787 PMCID: PMC4425971 DOI: 10.14814/phy2.12366] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Duchenne muscular dystrophy (DMD), the most common and severe muscular dystrophy, is caused by the absence of dystrophin. Muscle weakness and fragility (i.e., increased susceptibility to damage) are presumably due to structural instability of the myofiber cytoskeleton, but recent studies suggest that the increased presence of malformed/branched myofibers in dystrophic muscle may also play a role. We have previously studied myofiber morphology in healthy wild-type (WT) and dystrophic (MDX) skeletal muscle. Here, we examined myofiber excitability using high-speed confocal microscopy and the voltage-sensitive indicator di-8-butyl-amino-naphthyl-ethylene-pyridinium-propyl-sulfonate (di-8-ANEPPS) to assess the action potential (AP) properties. We also examined AP-induced Ca2+ transients using high-speed confocal microscopy with rhod-2, and assessed sarcolemma fragility using elastimetry. AP recordings showed an increased width and time to peak in malformed MDX myofibers compared to normal myofibers from both WT and MDX, but no significant change in AP amplitude. Malformed MDX myofibers also exhibited reduced AP-induced Ca2+ transients, with a further Ca2+ transient reduction in the branches of malformed MDX myofibers. Mechanical studies indicated an increased sarcolemma deformability and instability in malformed MDX myofibers. The data suggest that malformed myofibers are functionally different from myofibers with normal morphology. The differences seen in AP properties and Ca2+ signals suggest changes in excitability and remodeling of the global Ca2+ signal, both of which could underlie reported weakness in dystrophic muscle. The biomechanical changes in the sarcolemma support the notion that malformed myofibers are more susceptible to damage. The high prevalence of malformed myofibers in dystrophic muscle may contribute to the progressive strength loss and fragility seen in dystrophic muscles.
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Affiliation(s)
- Erick O Hernández-Ochoa
- Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Karla P Garcia-Pelagio
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Martin F Schneider
- Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
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Mázala DAG, Pratt SJP, Chen D, Molkentin JD, Lovering RM, Chin ER. SERCA1 overexpression minimizes skeletal muscle damage in dystrophic mouse models. Am J Physiol Cell Physiol 2015; 308:C699-709. [PMID: 25652448 DOI: 10.1152/ajpcell.00341.2014] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 02/01/2015] [Indexed: 02/04/2023]
Abstract
Duchenne muscular dystrophy (DMD) is characterized by progressive muscle wasting secondary to repeated muscle damage and inadequate repair. Elevations in intracellular free Ca²⁺ have been implicated in disease progression, and sarcoplasmic/endoplasmic reticulum Ca²⁺-ATPase 1 (SERCA1) overexpression has been shown to ameliorate the dystrophic phenotype in mdx mice. The purpose of this study was to assess the effects of SERCA1 overexpression in the more severe mdx/Utr(-/-) mouse model of DMD. Mice overexpressing SERCA1 were crossed with mdx/Utr ± mice to generate mdx/Utr(-/-)/+SERCA1 mice and compared with wild-type (WT), WT/+SERCA1, mdx/+SERCA1, and genotype controls. Mice were assessed at ∼12 wk of age for changes in Ca²⁺ handling, muscle mass, quadriceps torque, markers of muscle damage, and response to repeated eccentric contractions. SERCA1-overexpressing mice had a two- to threefold increase in maximal sarcoplasmic reticulum Ca²⁺-ATPase activity compared with WT which was associated with normalization in body mass for both mdx/+SERCA1 and mdx/Utr(-/-)/+SERCA1. Torque deficit in the quadriceps after eccentric injury was 2.7-fold greater in mdx/Utr(-/-) vs. WT mice, but only 1.5-fold greater in mdx/Utr(-/-)/+SERCA1 vs. WT mice, an attenuation of 44%. Markers of muscle damage (% centrally nucleated fibers, necrotic area, and serum creatine kinase levels) were higher in both mdx and mdx/Utr(-/-) vs. WT, and all were attenuated by overexpression of SERCA1. These data indicate that SERCA1 overexpression ameliorates functional impairments and cellular markers of damage in a more severe mouse model of DMD. These findings support targeting intracellular Ca²⁺ control as a therapeutic approach for DMD.
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Affiliation(s)
- Davi A G Mázala
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryand
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryand; and
| | - Dapeng Chen
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryand
| | - Jeffery D Molkentin
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryand; and
| | - Eva R Chin
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryand; Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryand; and Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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Abstract
Background: Muscle strains are one of the most common injuries treated by physicians. Standard conservative therapy for acute muscle strains usually involves short-term rest, ice, and nonsteroidal anti-inflammatory medications, but there is no clear consensus regarding treatments to accelerate recovery. Recently, clinical use of platelet-rich plasma (PRP) has gained momentum as an option for therapy and is appealing for many reasons, most notably because it provides growth factors in physiological proportions and it is autologous, safe, easily accessible, and potentially beneficial. Local delivery of PRP to injured muscles can hasten recovery of function. However, specific targeting of PRP to sites of tissue damage in vivo is a major challenge that can limit its efficacy. Hypothesis: Location of PRP delivery can be monitored and controlled in vivo with noninvasive tools. Study Design: Controlled laboratory study. Methods: Superparamagnetic iron oxide nanoparticles (SPIONs) can be visualized by both magnetic resonance imaging (MRI) (in vivo) and fluorescence microscopy (after tissue harvesting). PRP was labeled with SPIONs and administered by intramuscular injections of SPION-containing platelets. MRI was used to monitor the ability to manipulate and retain the location of PRP in vivo by placement of an external magnet. Platelets were isolated from whole blood and incubated with SPIONs. Following SPION incubation with PRP, a magnetic field was used to manipulate platelet location in culture dishes. In vivo, the tibialis anterior (TA) muscles of anesthetized Sprague-Dawley rats were injected with SPION-containing platelets, and MRI was used to track platelet position with and without a magnet worn over the TA muscles for 4 days. Results: The method used to isolate PRP yielded a high concentration (almost 4-fold increase) of platelets. In vitro experiments showed that the platelets successfully took up SPIONs and then rapidly responded to an applied magnetic field. Platelets without SPIONs did not respond to the magnetic field. In vivo experiments showed that the SPION-containing platelets can be noninvasively maintained at a specific site with the application of a magnetic field. Conclusion: PRP may be a useful product in the clinical treatment of muscle injuries, but one problem with using it as a therapeutic tool is retaining PRP at the site of injury. This study proposes a potential solution, with findings that support this method at the cell, whole muscle, and in vivo levels. Controlling the location of PRP will allow the clustering of PRP to enrich the target area with growth factors and will prevent loss of platelets over time at the site of injury.
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Affiliation(s)
- Tara Talaie
- Department of Orthopaedics, University of Maryland School of Medicine
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine
| | - Camilo Vanegas
- Department of Orthopaedics, University of Maryland School of Medicine
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine
| | - R Frank Henn
- Department of Orthopaedics, University of Maryland School of Medicine
| | - Paul Yarowsky
- Department of Pharmacology, University of Maryland School of Medicine
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García-Pelagio KP, Muriel J, O'Neill A, Desmond PF, Lovering RM, Lund L, Bond M, Bloch RJ. Myopathic changes in murine skeletal muscle lacking synemin. Am J Physiol Cell Physiol 2015; 308:C448-62. [PMID: 25567810 DOI: 10.1152/ajpcell.00331.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Diseases of striated muscle linked to intermediate filament (IF) proteins are associated with defects in the organization of the contractile apparatus and its links to costameres, which connect the sarcomeres to the cell membrane. Here we study the role in skeletal muscle of synemin, a type IV IF protein, by examining mice null for synemin (synm-null). Synm-null mice have a mild skeletal muscle phenotype. Tibialis anterior (TA) muscles show a significant decrease in mean fiber diameter, a decrease in twitch and tetanic force, and an increase in susceptibility to injury caused by lengthening contractions. Organization of proteins associated with the contractile apparatus and costameres is not significantly altered in the synm-null. Elastimetry of the sarcolemma and associated contractile apparatus in extensor digitorum longus myofibers reveals a reduction in tension consistent with an increase in sarcolemmal deformability. Although fatigue after repeated isometric contractions is more marked in TA muscles of synm-null mice, the ability of the mice to run uphill on a treadmill is similar to controls. Our results suggest that synemin contributes to linkage between costameres and the contractile apparatus and that the absence of synemin results in decreased fiber size and increased sarcolemmal deformability and susceptibility to injury. Thus synemin plays a moderate but distinct role in fast twitch skeletal muscle.
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Affiliation(s)
- Karla P García-Pelagio
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Joaquin Muriel
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Andrea O'Neill
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Patrick F Desmond
- Program in Biochemistry and Molecular Biology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Richard M Lovering
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Linda Lund
- Merrick School of Business, University of Baltimore, Baltimore, Maryland; and
| | - Meredith Bond
- College of Sciences and Health Professions, Cleveland State University, Cleveland, Ohio
| | - Robert J Bloch
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, Maryland;
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47
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Garcia-Pelagio K, Muriel J, ÓNeill A, Desmond P, Lovering RM, Lund L, Bond M, Bloch R. Myopathic Changes in Murine Skeletal Muscle Lacking Synemin. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.2319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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48
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Hernández-Ochoa EO, Vanegas C, Pratt SJ, Lovering RM, Schneider MF. Characterization of Dual Mutant RyR1D-S100A1KO Mice with Disrupted CaM and S100A1 Binding to CaMBD2 and Lacking S100A1 Expression. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.1487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Abstract
In patients with muscle injury or muscle disease, assessment of muscle damage is typically limited to clinical signs, such as tenderness, strength, range of motion, and more recently, imaging studies. Biological markers can also be used in measuring muscle injury, such as increased creatine kinase levels in the blood, but these are not always correlated with loss in muscle function (i.e. loss of force production). This is even true of histological findings from animals, which provide a "direct measure" of damage, but do not account for loss of function. The most comprehensive measure of the overall health of the muscle is contractile force. To date, animal models testing contractile force have been limited to the muscle groups moving the ankle. Here we describe an in vivo animal model for the quadriceps, with abilities to measure torque, produce a reliable muscle injury, and follow muscle recovery within the same animal over time. We also describe a second model used for direct measurement of force from an isolated quadriceps muscle in situ.
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Affiliation(s)
- Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD
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Matthews CC, Lovering RM, Bowen TG, Fishman PS. Tetanus toxin preserves skeletal muscle contractile force and size during limb immobilization. Muscle Nerve 2014; 50:759-66. [DOI: 10.1002/mus.24231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 02/19/2014] [Accepted: 02/27/2014] [Indexed: 01/09/2023]
Affiliation(s)
- Christopher C. Matthews
- Research Service, VA Maryland Health Care System; 10 North Greene Street Baltimore Maryland 21201 USA
- Department of Neurology; School of Medicine, University of Maryland; Baltimore Maryland USA
| | - Richard M. Lovering
- Department of Orthopaedics; School of Medicine, University of Maryland; Baltimore Maryland USA
| | - Thomas G. Bowen
- Research Service, VA Maryland Health Care System; 10 North Greene Street Baltimore Maryland 21201 USA
| | - Paul S. Fishman
- Research Service, VA Maryland Health Care System; 10 North Greene Street Baltimore Maryland 21201 USA
- Department of Neurology; School of Medicine, University of Maryland; Baltimore Maryland USA
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