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Schneidereit D, Bauer J, Mnuskina S, Nübler S, Cacciani N, Mühlberg A, Kreiss L, Ritter P, Schürmann S, Larsson L, Friedrich O. CAS3D: 3D quantitative morphometry on Second Harmonic Generation image volumes from single skeletal muscle fibers. Comput Biol Med 2024; 178:108618. [PMID: 38925088 DOI: 10.1016/j.compbiomed.2024.108618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 06/28/2024]
Abstract
The CAS3D image processing method intuitively applies a combination of Fourier space and real space 3D analysis algorithms to volumetric images of single skeletal muscle fiber Myosin II Second Harmonic Generation (SHG) XYZ image data. Our developed tool automatically quantifies the myofibrillar orientation in muscle samples by determining the cosine angle sum of intensity gradients in 3D (CAS3D) while determining the mean sarcomere length (SL) and sample orientation. The expected CAS3D values could be reproduced from ideal artificial data sets. Applied random noise in artificial images lowers the detected CAS3D value, and for noise levels below 20%, the correlation can be approximated by a linear function with a slope of -0.006 CAS3D/noise%. The deviations in SL and orientation detection were determined on ideal and noisy artificial data sets and were statistically indistinguishable from 0 (null hypothesis t-test P > 0.1). The software was applied to a previously published data set of single skeletal muscle fiber volumetric SHG image data from a rat intensive care unit (ICU) model of ventilator-induced diaphragm dysfunction (VIDD) with treatment regimens involving the small anti-inflammatory molecules BGP-15, vamorolone, or prednisolone. Our method reliably reproduced the results of the previous work and improved the standard deviation of the cosine angle sum detection in all sample groups from a mean of 0.03 to 0.008. This improvement is achieved by applying analysis algorithms to the whole volumetric images in 3D in contrast to the previously common method of slice-wise XY analysis.
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Affiliation(s)
- Dominik Schneidereit
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany.
| | - Julian Bauer
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Sofia Mnuskina
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Stefanie Nübler
- Medical Faculty, IPASUM, Friedrich-Alexander Universität Erlangen-Nürnberg, Kochstrasse 19, 91054 Erlangen, Germany
| | - Nicola Cacciani
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavaegen 30, 17164 Stockholm, Sweden
| | - Alexander Mühlberg
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Lucas Kreiss
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Paul Ritter
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Sebastian Schürmann
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
| | - Lars Larsson
- Department of Physiology and Pharmacology, Karolinska Institutet, Solnavaegen 30, 17164 Stockholm, Sweden
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander Universität Erlangen-Nürnberg, Paul-Gordan-Strasse 3, 91052 Erlangn, Germany
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2
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Mühlberg A, Ritter P, Langer S, Goossens C, Nübler S, Schneidereit D, Taubmann O, Denzinger F, Nörenberg D, Haug M, Schürmann S, Horstmeyer R, Maier AK, Goldmann WH, Friedrich O, Kreiss L. SEMPAI: a Self-Enhancing Multi-Photon Artificial Intelligence for Prior-Informed Assessment of Muscle Function and Pathology. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2206319. [PMID: 37582656 PMCID: PMC10558688 DOI: 10.1002/advs.202206319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 06/30/2023] [Indexed: 08/17/2023]
Abstract
Deep learning (DL) shows notable success in biomedical studies. However, most DL algorithms work as black boxes, exclude biomedical experts, and need extensive data. This is especially problematic for fundamental research in the laboratory, where often only small and sparse data are available and the objective is knowledge discovery rather than automation. Furthermore, basic research is usually hypothesis-driven and extensive prior knowledge (priors) exists. To address this, the Self-Enhancing Multi-Photon Artificial Intelligence (SEMPAI) that is designed for multiphoton microscopy (MPM)-based laboratory research is presented. It utilizes meta-learning to optimize prior (and hypothesis) integration, data representation, and neural network architecture simultaneously. By this, the method allows hypothesis testing with DL and provides interpretable feedback about the origin of biological information in 3D images. SEMPAI performs multi-task learning of several related tasks to enable prediction for small datasets. SEMPAI is applied on an extensive MPM database of single muscle fibers from a decade of experiments, resulting in the largest joint analysis of pathologies and function for single muscle fibers to date. It outperforms state-of-the-art biomarkers in six of seven prediction tasks, including those with scarce data. SEMPAI's DL models with integrated priors are superior to those without priors and to prior-only approaches.
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Affiliation(s)
- Alexander Mühlberg
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
| | - Paul Ritter
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
- Erlangen Graduate School in Advanced Optical TechnologiesPaul‐Gordan‐Str. 691052ErlangenGermany
| | - Simon Langer
- Pattern Recognition LabDepartment of Computer ScienceFriedrich‐Alexander University Erlangen‐NurembergMartensstr. 391058ErlangenGermany
| | - Chloë Goossens
- Clinical Division and Laboratory of Intensive Care MedicineKU LeuvenUZ Herestraat 49 – P.O. box 7003Leuven3000Belgium
| | - Stefanie Nübler
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
| | - Dominik Schneidereit
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
- Erlangen Graduate School in Advanced Optical TechnologiesPaul‐Gordan‐Str. 691052ErlangenGermany
| | - Oliver Taubmann
- Pattern Recognition LabDepartment of Computer ScienceFriedrich‐Alexander University Erlangen‐NurembergMartensstr. 391058ErlangenGermany
| | - Felix Denzinger
- Pattern Recognition LabDepartment of Computer ScienceFriedrich‐Alexander University Erlangen‐NurembergMartensstr. 391058ErlangenGermany
| | - Dominik Nörenberg
- Department of Radiology and Nuclear MedicineUniversity Medical Center MannheimMedical Faculty MannheimTheodor‐Kutzer‐Ufer 1–368167MannheimGermany
| | - Michael Haug
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
| | - Sebastian Schürmann
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
| | - Roarke Horstmeyer
- Computational Optics LabDepartment of Biomedical EngineeringDuke University101 Science DrDurhamNC27708USA
| | - Andreas K. Maier
- Pattern Recognition LabDepartment of Computer ScienceFriedrich‐Alexander University Erlangen‐NurembergMartensstr. 391058ErlangenGermany
| | - Wolfgang H. Goldmann
- Biophysics GroupDepartment of PhysicsFriedrich‐Alexander University Erlangen‐NurembergHenkestr. 9191052ErlangenGermany
| | - Oliver Friedrich
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
- Erlangen Graduate School in Advanced Optical TechnologiesPaul‐Gordan‐Str. 691052ErlangenGermany
| | - Lucas Kreiss
- Institute of Medical BiotechnologyDepartment of Chemical and Biological EngineeringFriedrich‐Alexander University Erlangen‐NurembergPaul‐Gordan‐Str. 391052ErlangenGermany
- Erlangen Graduate School in Advanced Optical TechnologiesPaul‐Gordan‐Str. 691052ErlangenGermany
- Computational Optics LabDepartment of Biomedical EngineeringDuke University101 Science DrDurhamNC27708USA
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Harriot AD, Altair Morris T, Vanegas C, Kallenbach J, Pinto K, Joca HC, Moutin MJ, Shi G, Ursitti JA, Grosberg A, Ward CW. Detyrosinated microtubule arrays drive myofibrillar malformations in mdx muscle fibers. Front Cell Dev Biol 2023; 11:1209542. [PMID: 37691825 PMCID: PMC10485621 DOI: 10.3389/fcell.2023.1209542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023] Open
Abstract
Altered myofibrillar structure is a consequence of dystrophic pathology that impairs skeletal muscle contractile function and increases susceptibility to contraction injury. In murine Duchenne muscular dystrophy (mdx), myofibrillar alterations are abundant in advanced pathology (>4 months), an age where we formerly established densified microtubule (MT) arrays enriched in detyrosinated (deTyr) tubulin as negative disease modifiers impacting cell mechanics and mechanotransduction. Given the essential role of deTyr-enriched MT arrays in myofibrillar growth, maintenance, and repair, we examined the increased abundance of these arrays as a potential mechanism for these myofibrillar alterations. Here we find an increase in deTyr-tubulin as an early event in dystrophic pathology (4 weeks) with no evidence myofibrillar alterations. At 16 weeks, we show deTyr-enriched MT arrays significantly densified and co-localized to areas of myofibrillar malformation. Profiling the enzyme complexes responsible for deTyr-tubulin, we identify vasohibin 2 (VASH2) and small vasohibin binding protein (SVBP) significantly elevated in the mdx muscle at 4 weeks. Using the genetic increase in VASH2/SVBP expression in 4 weeks wild-type mice we find densified deTyr-enriched MT arrays that co-segregate with myofibrillar malformations similar to those in the 16 weeks mdx. Given that no changes in sarcomere organization were identified in fibers expressing sfGFP as a control, we conclude that disease-dependent densification of deTyr-enriched MT arrays underscores the altered myofibrillar structure in dystrophic skeletal muscle fibers.
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Affiliation(s)
- Anicca D. Harriot
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Tessa Altair Morris
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
| | - Camilo Vanegas
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jacob Kallenbach
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Kaylie Pinto
- Department of Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Humberto C. Joca
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Marie-Jo Moutin
- INSERM U1216 Centre National de la Recherche Scientifique, Grenoble Institut Neurosciences, University Grenoble Alpes, Grenoble, France
| | - Guoli Shi
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jeanine A. Ursitti
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anna Grosberg
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
- Department of Chemical and Biomolecular Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
| | - Christopher W. Ward
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
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Mnuskina S, Bauer J, Wirth-Hücking A, Schneidereit D, Nübler S, Ritter P, Cacciani N, Li M, Larsson L, Friedrich O. Single fibre cytoarchitecture in ventilator-induced diaphragm dysfunction (VIDD) assessed by quantitative morphometry second harmonic generation imaging: Positive effects of BGP-15 chaperone co-inducer and VBP-15 dissociative corticosteroid treatment. Front Physiol 2023; 14:1207802. [PMID: 37440999 PMCID: PMC10333583 DOI: 10.3389/fphys.2023.1207802] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 06/01/2023] [Indexed: 07/15/2023] Open
Abstract
Ventilator-induced diaphragm dysfunction (VIDD) is a common sequela of intensive care unit (ICU) treatment requiring mechanical ventilation (MV) and neuromuscular blockade (NMBA). It is characterised by diaphragm weakness, prolonged respirator weaning and adverse outcomes. Dissociative glucocorticoids (e.g., vamorolone, VBP-15) and chaperone co-inducers (e.g., BGP-15) previously showed positive effects in an ICU-rat model. In limb muscle critical illness myopathy, preferential myosin loss prevails, while myofibrillar protein post-translational modifications are more dominant in VIDD. It is not known whether the marked decline in specific force (force normalised to cross-sectional area) is a pure consequence of altered contractility signaling or whether diaphragm weakness also has a structural correlate through sterical remodeling of myofibrillar cytoarchitecture, how quickly it develops, and to which extent VBP-15 or BGP-15 may specifically recover myofibrillar geometry. To address these questions, we performed label-free multiphoton Second Harmonic Generation (SHG) imaging followed by quantitative morphometry in single diaphragm muscle fibres from healthy rats subjected to five or 10 days of MV + NMBA to simulate ICU treatment without underlying confounding pathology (like sepsis). Rats received daily treatment of either Prednisolone, VBP-15, BGP-15 or none. Myosin-II SHG signal intensities, fibre diameters (FD) as well as the parameters of myofibrillar angular parallelism (cosine angle sum, CAS) and in-register of adjacent myofibrils (Vernier density, VD) were computed from SHG images. ICU treatment caused a decline in FD at day 10 as well as a significant decline in CAS and VD from day 5. Vamorolone effectively recovered FD at day 10, while BGP-15 was more effective at day 5. BGP-15 was more effective than VBP-15 in recovering CAS at day 10 although not to control levels. In-register VD levels were restored at day 10 by both compounds. Our study is the first to provide quantitative insights into VIDD-related myofibrillar remodeling unravelled by SHG imaging, suggesting that both VBP-15 and BGP-15 can effectively ameliorate the structure-related dysfunction in VIDD.
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Affiliation(s)
- Sofia Mnuskina
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Julian Bauer
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Anette Wirth-Hücking
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Dominik Schneidereit
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefanie Nübler
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Paul Ritter
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Nicola Cacciani
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Meishan Li
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Lars Larsson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Neuroscience, Clinical Neurophysiology, Karolinska Institutet, Stockholm, Sweden
- Viron Molecular Medicine Institute, Boston, MA, United States
| | - Oliver Friedrich
- Department of Chemical and Biological Engineering (CBI), Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
- School of Medical Sciences, University of New South Wales, Kensington Campus, Sydney, NSW, Australia
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Schneidereit D, Nübler S, Friedrich O. Second Harmonic Generation Morphometry of Muscle Cytoarchitecture in Living Cells. Methods Mol Biol 2023; 2644:267-285. [PMID: 37142928 DOI: 10.1007/978-1-0716-3052-5_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The architectural structure of cells is essential for the cells' function, which becomes especially apparent in the highly "structure functionally" tuned skeletal muscle cells. Here, structural changes in the microstructure can have a direct impact on performance parameters, such as isometric or tetanic force production. The microarchitecture of the actin-myosin lattice in muscle cells can be detected noninvasively in living cells and in 3D by using second harmonic generation (SHG) microscopy, forgoing the need to alter samples by introducing fluorescent probes into them. Here, we provide tools and step-by-step protocols to guide the processes of obtaining SHG microscopy image data from samples, as well as extracting characteristic values from the image data to quantify the cellular microarchitecture using characteristic patterns of myofibrillar lattice alignments.
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Affiliation(s)
- Dominik Schneidereit
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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Gineste C, Youhanna S, Vorrink SU, Henriksson S, Hernández A, Cheng AJ, Chaillou T, Buttgereit A, Schneidereit D, Friedrich O, Hultenby K, Bruton JD, Ivarsson N, Sandblad L, Lauschke VM, Westerblad H. Enzymatically dissociated muscle fibers display rapid dedifferentiation and impaired mitochondrial calcium control. iScience 2022; 25:105654. [PMID: 36479146 PMCID: PMC9720020 DOI: 10.1016/j.isci.2022.105654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 07/19/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
Cells rapidly lose their physiological phenotype upon disruption of their extracellular matrix (ECM)-intracellular cytoskeleton interactions. By comparing adult mouse skeletal muscle fibers, isolated either by mechanical dissection or by collagenase-induced ECM digestion, we investigated acute effects of ECM disruption on cellular and mitochondrial morphology, transcriptomic signatures, and Ca2+ handling. RNA-sequencing showed striking differences in gene expression patterns between the two isolation methods with enzymatically dissociated fibers resembling myopathic phenotypes. Mitochondrial appearance was grossly similar in the two groups, but 3D electron microscopy revealed shorter and less branched mitochondria following enzymatic dissociation. Repeated contractions resulted in a prolonged mitochondrial Ca2+ accumulation in enzymatically dissociated fibers, which was partially prevented by cyclophilin inhibitors. Of importance, muscle fibers of mice with severe mitochondrial myopathy show pathognomonic mitochondrial Ca2+ accumulation during repeated contractions and this accumulation was concealed with enzymatic dissociation, making this an ambiguous method in studies of native intracellular Ca2+ fluxes.
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Affiliation(s)
- Charlotte Gineste
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sonia Youhanna
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sabine U. Vorrink
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sara Henriksson
- Umeå Core Facility for Electron Microscopy, Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Andrés Hernández
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Arthur J. Cheng
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Thomas Chaillou
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Andreas Buttgereit
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University of Erlangen-Nürnberg, 91052 Erlangen, Germany
| | - Dominik Schneidereit
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University of Erlangen-Nürnberg, 91052 Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander University of Erlangen-Nürnberg, 91052 Erlangen, Germany
| | - Kjell Hultenby
- Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, 141 86 Huddinge, Sweden
| | - Joseph D. Bruton
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Niklas Ivarsson
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Linda Sandblad
- Umeå Core Facility for Electron Microscopy, Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Volker M. Lauschke
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
- University of Tübingen, Tübingen, Germany
| | - Håkan Westerblad
- Department of Physiology and Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden
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Ritter P, Nübler S, Buttgereit A, Smith LR, Mühlberg A, Bauer J, Michael M, Kreiß L, Haug M, Barton E, Friedrich O. Myofibrillar Lattice Remodeling Is a Structural Cytoskeletal Predictor of Diaphragm Muscle Weakness in a Fibrotic mdx ( mdx Cmah-/-) Model. Int J Mol Sci 2022; 23:ijms231810841. [PMID: 36142754 PMCID: PMC9500669 DOI: 10.3390/ijms231810841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/24/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a degenerative genetic myopathy characterized by complete absence of dystrophin. Although the mdx mouse lacks dystrophin, its phenotype is milder compared to DMD patients. The incorporation of a null mutation in the Cmah gene led to a more DMD-like phenotype (i.e., more fibrosis). Although fibrosis is thought to be the major determinant of ‘structural weakness’, intracellular remodeling of myofibrillar geometry was shown to be a major cellular determinant thereof. To dissect the respective contribution to muscle weakness, we assessed biomechanics and extra- and intracellular architecture of whole muscle and single fibers from extensor digitorum longus (EDL) and diaphragm. Despite increased collagen contents in both muscles, passive stiffness in mdx Cmah−/− diaphragm was similar to wt mice (EDL muscles were twice as stiff). Isometric twitch and tetanic stresses were 50% reduced in mdx Cmah−/− diaphragm (15% in EDL). Myofibrillar architecture was severely compromised in mdx Cmah−/− single fibers of both muscle types, but more pronounced in diaphragm. Our results show that the mdx Cmah−/− genotype reproduces DMD-like fibrosis but is not associated with changes in passive visco-elastic muscle stiffness. Furthermore, detriments in active isometric force are compatible with the pronounced myofibrillar disarray of the dystrophic background.
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Affiliation(s)
- Paul Ritter
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Correspondence:
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Andreas Buttgereit
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Lucas R. Smith
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95618, USA
| | - Alexander Mühlberg
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Julian Bauer
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Mena Michael
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Lucas Kreiß
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Michael Haug
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Elisabeth Barton
- College of Health & Human Performance, University of Florida, Gainesville, FL 32611, USA
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- School of Medical Sciences, University of New South Wales, Wallace Wurth Building, 18 High Str., Sydney, NSW 2052, Australia
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8
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Haug M, Reischl B, Nübler S, Kiriaev L, Mázala DAG, Houweling PJ, North KN, Friedrich O, Head SI. Absence of the Z-disc protein α-actinin-3 impairs the mechanical stability of Actn3KO mouse fast-twitch muscle fibres without altering their contractile properties or twitch kinetics. Skelet Muscle 2022; 12:14. [PMID: 35733150 PMCID: PMC9219180 DOI: 10.1186/s13395-022-00295-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 05/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A common polymorphism (R577X) in the ACTN3 gene results in the complete absence of the Z-disc protein α-actinin-3 from fast-twitch muscle fibres in ~ 16% of the world's population. This single gene polymorphism has been subject to strong positive selection pressure during recent human evolution. Previously, using an Actn3KO mouse model, we have shown in fast-twitch muscles, eccentric contractions at L0 + 20% stretch did not cause eccentric damage. In contrast, L0 + 30% stretch produced a significant ~ 40% deficit in maximum force; here, we use isolated single fast-twitch skeletal muscle fibres from the Actn3KO mouse to investigate the mechanism underlying this. METHODS Single fast-twitch fibres are separated from the intact muscle by a collagenase digest procedure. We use label-free second harmonic generation (SHG) imaging, ultra-fast video microscopy and skinned fibre measurements from our MyoRobot automated biomechatronics system to study the morphology, visco-elasticity, force production and mechanical strength of single fibres from the Actn3KO mouse. Data are presented as means ± SD and tested for significance using ANOVA. RESULTS We show that the absence of α-actinin-3 does not affect the visco-elastic properties or myofibrillar force production. Eccentric contractions demonstrated that chemically skinned Actn3KO fibres are mechanically weaker being prone to breakage when eccentrically stretched. Furthermore, SHG images reveal disruptions in the myofibrillar alignment of Actn3KO fast-twitch fibres with an increase in Y-shaped myofibrillar branching. CONCLUSIONS The absence of α-actinin-3 from the Z-disc in fast-twitch fibres disrupts the organisation of the myofibrillar proteins, leading to structural weakness. This provides a mechanistic explanation for our earlier findings that in vitro intact Actn3KO fast-twitch muscles are significantly damaged by L0 + 30%, but not L0 + 20%, eccentric contraction strains. Our study also provides a possible mechanistic explanation as to why α-actinin-3-deficient humans have been reported to have a faster decline in muscle function with increasing age, that is, as sarcopenia reduces muscle mass and force output, the eccentric stress on the remaining functional α-actinin-3 deficient fibres will be increased, resulting in fibre breakages.
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Affiliation(s)
- Michael Haug
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia.,School of Medical Science, University of New South Wales, Sydney, NSW, Australia
| | - Davi A G Mázala
- Department of Kinesiology, College of Health Professions, Towson University, Towson, MD, USA
| | - Peter J Houweling
- Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Kathryn N North
- Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.,School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia.,School of Medical Science, University of New South Wales, Sydney, NSW, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia. .,School of Medical Science, University of New South Wales, Sydney, NSW, Australia. .,Murdoch Children's Research Institute, Melbourne, VIC, Australia.
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9
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Kiriaev L, Kueh S, Morley JW, North KN, Houweling PJ, Head SI. Lifespan Analysis of Dystrophic mdx Fast-Twitch Muscle Morphology and Its Impact on Contractile Function. Front Physiol 2021; 12:771499. [PMID: 34950049 PMCID: PMC8689589 DOI: 10.3389/fphys.2021.771499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/08/2021] [Indexed: 11/13/2022] Open
Abstract
Duchenne muscular dystrophy is caused by the absence of the protein dystrophin from skeletal muscle and is characterized by progressive cycles of necrosis/regeneration. Using the dystrophin deficient mdx mouse model, we studied the morphological and contractile chronology of dystrophic skeletal muscle pathology in fast-twitch Extensor Digitorum Longus muscles from animals 4–22 months of age containing 100% regenerated muscle fibers. Catastrophically, the older age groups lost ∼80% of their maximum force after one eccentric contraction (EC) of 20% strain with the greatest loss of ∼92% recorded in senescent 22-month-old mdx mice. In old age groups, there was minimal force recovery ∼24% after 120 min, correlated with a dramatic increase in the number and complexity of branched fibers. This data supports our two-phase model where a “tipping point” is reached when branched fibers rupture irrevocably on EC. These findings have important implications for pre-clinical drug studies and genetic rescue strategies.
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Affiliation(s)
- Leonit Kiriaev
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
- *Correspondence: Leonit Kiriaev,
| | - Sindy Kueh
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - John W. Morley
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Kathryn N. North
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| | - Peter J. Houweling
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| | - Stewart I. Head
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
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10
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Kiriaev L, Houweling PJ, North KN, Head SI. Loss of α-actinin-3 confers protection from eccentric contraction damage in fast-twitch EDL muscles from aged mdx dystrophic mice by reducing pathological fibre branching. Hum Mol Genet 2021; 31:1417-1429. [PMID: 34761268 PMCID: PMC9071495 DOI: 10.1093/hmg/ddab326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/27/2021] [Accepted: 11/02/2021] [Indexed: 11/14/2022] Open
Abstract
The common null polymorphism (R577X) in the ACTN3 gene is present in over 1.5 billion people worldwide and results in the absence of the protein α-actinin-3 from the Z-discs of fast-twitch skeletal muscle fibres. We have previously reported that this polymorphism is a modifier of dystrophin deficient Duchenne Muscular Dystrophy. To investigate the mechanism underlying this we use a double knockout (dk)Actn3KO/mdx (dKO) mouse model which lacks both dystrophin and sarcomere α-actinin-3. We used dKO mice and mdx dystrophic mice at 12 months (aged) to investigate the correlation between morphological changes to the fast-twitch dKO EDL and the reduction in force deficit produced by an in vitro eccentric contraction protocol. In the aged dKO mouse we found a marked reduction in fibre branching complexity that correlated with protection from eccentric contraction induced force deficit. Complex branches in the aged dKO EDL fibres (28%) were substantially reduced compared to aged mdx EDL fibres (68%) and this correlates with a graded force loss over three eccentric contractions for dKO muscles (~35% after first contraction, ~ 66% overall) compared to an abrupt drop in mdx upon the first eccentric contraction (~73% after first contraction, ~ 89% after three contractions). In dKO protection from eccentric contraction damage was linked with a doubling of SERCA1 pump density the EDL. We propose that the increased oxidative metabolism of fast-twitch glycolytic fibres characteristic of the null polymorphism (R577X) and increase in SR Ca2+ pump proteins reduces muscle fibre branching and decreases susceptibility to eccentric injury in the dystrophinopathies.
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Affiliation(s)
- Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Peter J Houweling
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Kathryn N North
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, NSW, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia
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11
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Kiriaev L, Kueh S, Morley JW, Houweling PJ, Chan S, North KN, Head SI. Dystrophin-negative slow-twitch soleus muscles are not susceptible to eccentric contraction induced injury over the lifespan of the mdx mouse. Am J Physiol Cell Physiol 2021; 321:C704-C720. [PMID: 34432537 DOI: 10.1152/ajpcell.00122.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 08/09/2021] [Indexed: 11/22/2022]
Abstract
Duchenne muscular dystrophy (DMD) is the second most common fatal genetic disease in humans and is characterized by the absence of a functional copy of the protein dystrophin from skeletal muscle. In dystrophin-negative humans and rodents, regenerated skeletal muscle fibers show abnormal branching. The number of fibers with branches and the complexity of branching increases with each cycle of degeneration/regeneration. Previously, using the mdx mouse model of DMD, we have proposed that once the number and complexity of branched fibers present in dystrophic fast-twitch EDL muscle surpasses a stable level, we term the "tipping point," the branches, in and of themselves, mechanically weaken the muscle by rupturing when subjected to high forces during eccentric contractions. Here, we use the slow-twitch soleus muscle from the dystrophic mdx mouse to study prediseased "periambulatory" dystrophy at 2-3 wk, the peak regenerative "adult" phase at 6-9 wk, and "old" at 58-112 wk. Using isolated mdx soleus muscles, we examined contractile function and response to eccentric contraction correlated with the amount and complexity of regenerated branched fibers. The intact muscle was enzymatically dispersed into individual fibers in order to count fiber branching and some muscles were optically cleared to allow laser scanning confocal microscopy. We demonstrate throughout the lifespan of the mdx mouse that dystrophic slow-twitch soleus muscle is no more susceptible to eccentric contraction-induced injury than age-matched littermate controls and that this is correlated with a reduction in the number and complexity of branched fibers compared with fast-twitch dystrophic EDL muscles.
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MESH Headings
- Age Factors
- Animals
- Disease Models, Animal
- Dystrophin/deficiency
- Dystrophin/genetics
- Kinetics
- Male
- Mice, Inbred mdx
- Muscle Contraction
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle Fibers, Fast-Twitch/pathology
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle Fibers, Slow-Twitch/pathology
- Muscle Strength
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/physiopathology
- Mutation
- Mice
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Affiliation(s)
- Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Sindy Kueh
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - John W Morley
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Peter J Houweling
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Stephen Chan
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Kathryn N North
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
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12
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Goossens C, Weckx R, Derde S, Van Helleputte L, Schneidereit D, Haug M, Reischl B, Friedrich O, Van Den Bosch L, Van den Berghe G, Langouche L. Impact of prolonged sepsis on neural and muscular components of muscle contractions in a mouse model. J Cachexia Sarcopenia Muscle 2021; 12:443-455. [PMID: 33465304 PMCID: PMC8061378 DOI: 10.1002/jcsm.12668] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/19/2020] [Accepted: 12/16/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Prolonged critically ill patients frequently develop debilitating muscle weakness that can affect both peripheral nerves and skeletal muscle. In-depth knowledge on the temporal contribution of neural and muscular components to muscle weakness is currently incomplete. METHODS We used a fluid-resuscitated, antibiotic-treated, parenterally fed murine model of prolonged (5 days) sepsis-induced muscle weakness (caecal ligation and puncture; n = 148). Electromyography (EMG) measurements were performed in two nerve-muscle complexes, combined with histological analysis of neuromuscular junction denervation, axonal degeneration, and demyelination. In situ muscle force measurements distinguished neural from muscular contribution to reduced muscle force generation. In myofibres, imaging and biomechanics were combined to evaluate myofibrillar contractile calcium sensitivity, sarcomere organization, and fibre structural properties. Myosin and actin protein content and titin gene expression were measured on the whole muscle. RESULTS Five days of sepsis resulted in increased EMG latency (P = 0.006) and decreased EMG amplitude (P < 0.0001) in the dorsal caudal tail nerve-tail complex, whereas only EMG amplitude was affected in the sciatic nerve-gastrocnemius muscle complex (P < 0.0001). Myelin sheath abnormalities (P = 0.2), axonal degeneration (number of axons; P = 0.4), and neuromuscular junction denervation (P = 0.09) were largely absent in response to sepsis, but signs of axonal swelling [higher axon area (P < 0.0001) and g-ratio (P = 0.03)] were observed. A reduction in maximal muscle force was present after indirect nerve stimulation (P = 0.007) and after direct muscle stimulation (P = 0.03). The degree of force reduction was similar with both stimulations (P = 0.2), identifying skeletal muscle, but not peripheral nerves, as the main contributor to muscle weakness. Myofibrillar calcium sensitivity of the contractile apparatus was unaffected by sepsis (P ≥ 0.6), whereas septic myofibres displayed disorganized sarcomeres (P < 0.0001) and altered myofibre axial elasticity (P < 0.0001). Septic myofibres suffered from increased rupturing in a passive stretching protocol (25% more than control myofibres; P = 0.04), which was associated with impaired myofibre active force generation (P = 0.04), linking altered myofibre integrity to function. Sepsis also caused a reduction in muscle titin gene expression (P = 0.04) and myosin and actin protein content (P = 0.05), but not the myosin-to-actin ratio (P = 0.7). CONCLUSIONS Prolonged sepsis-induced muscle weakness may predominantly be related to a disruption in myofibrillar cytoarchitectural structure, rather than to neural abnormalities.
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Affiliation(s)
- Chloë Goossens
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Ruben Weckx
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Sarah Derde
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Lawrence Van Helleputte
- Experimental Neurology and Leuven Brain Institute, Department of Neurosciences, KU Leuven, Leuven, Belgium.,Laboratory of Neurobiology, VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Dominik Schneidereit
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Haug
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Ludo Van Den Bosch
- Experimental Neurology and Leuven Brain Institute, Department of Neurosciences, KU Leuven, Leuven, Belgium.,Laboratory of Neurobiology, VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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13
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Schneidereit D, Bröllochs A, Ritter P, Kreiß L, Mokhtari Z, Beilhack A, Krönke G, Ackermann JA, Faas M, Grüneboom A, Schürmann S, Friedrich O. An advanced optical clearing protocol allows label-free detection of tissue necrosis via multiphoton microscopy in injured whole muscle. Am J Cancer Res 2021; 11:2876-2891. [PMID: 33456578 PMCID: PMC7806485 DOI: 10.7150/thno.51558] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/12/2020] [Indexed: 01/27/2023] Open
Abstract
Rationale: Structural remodeling or damage as a result of disease or injury is often not evenly distributed throughout a tissue but strongly depends on localization and extent of damaging stimuli. Skeletal muscle as a mechanically active organ can express signs of local or even systemic myopathic damage, necrosis, or repair. Conventionally, muscle biopsies (patients) or whole muscles (animal models) are mechanically sliced and stained to assess structural alterations histologically. Three-dimensional tissue information can be obtained by applying deep imaging modalities, e.g. multiphoton or light-sheet microscopy. Chemical clearing approaches reduce scattering, e.g. through matching refractive tissue indices, to overcome optical penetration depth limits in thick tissues. Methods: Here, we optimized a range of different clearing protocols. We find aqueous solution-based protocols employing (20-80%) 2,2'-thiodiethanol (TDE) to be advantageous over organic solvents (dibenzyl ether, cinnamate) regarding the preservation of muscle morphology, ease-of-use, hazard level, and costs. Results: Applying TDE clearing to a mouse model of local cardiotoxin (CTX)-induced muscle necrosis, a complete loss of myosin-II signals was observed in necrotic areas with little change in fibrous collagen or autofluorescence (AF) signals. The 3D aspect of myofiber integrity could be assessed, and muscle necrosis in whole muscle was quantified locally via the ratios of detected AF, forward- and backward-scattered Second Harmonic Generation (fSHG, bSHG) signals. Conclusion: TDE optical clearing is a versatile tool to study muscle architecture in conjunction with label-free multiphoton imaging in 3D in injury/myopathy models and might also be useful in studying larger biofabricated constructs in regenerative medicine.
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14
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Effect of myofibril architecture on the active contraction of dystrophic muscle. A mathematical model. J Mech Behav Biomed Mater 2020; 114:104214. [PMID: 33234495 DOI: 10.1016/j.jmbbm.2020.104214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 10/27/2020] [Accepted: 11/15/2020] [Indexed: 11/23/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a muscle degenerative disease caused by a mutation in the dystrophin gene. The lack of dystrophin leads to persistent inflammation, degeneration/regeneration cycles of muscle fibers, Ca2+ dysregulation, incompletely regenerated fibers, necrosis, fibrotic tissue replacement, and alterations in the fiber ultrastructure i.e., myofibril misalignment and branched fibers. This work aims to develop a comprehensive chemo-mechanical model of muscle-skeletal tissue accounting for dispersion in myofibrillar orientations, in addition to the disorders in sarcomere pattern and the fiber branching. The model results confirm a significant correlation between the myofibrillar dispersion and the reduction of isometric force in the dystrophic muscle and indicate that the reduction of contraction velocity in the dystrophic muscle seems to be associated with the local disorders in the sarcomere patterns of the myofibrils. Also, the implemented model can predict the force-velocity response to both concentric and eccentric loading. The resulting model represents an original approach to account for defects in the muscle ultrastructure caused by pathologies as DMD.
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15
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Pollmann C, Haug M, Reischl B, Prölß G, Pöschel T, Rupitsch SJ, Clemen CS, Schröder R, Friedrich O. Growing Old Too Early: Skeletal Muscle Single Fiber Biomechanics in Ageing R349P Desmin Knock-in Mice Using the MyoRobot Technology. Int J Mol Sci 2020; 21:ijms21155501. [PMID: 32752098 PMCID: PMC7432536 DOI: 10.3390/ijms21155501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/21/2020] [Accepted: 07/28/2020] [Indexed: 11/16/2022] Open
Abstract
Muscle biomechanics relies on active motor protein assembly and passive strain transmission through cytoskeletal structures. The desmin filament network aligns myofibrils at the z-discs, provides nuclear–sarcolemmal anchorage and may also serve as memory for muscle repositioning following large strains. Our previous analyses of R349P desmin knock-in mice, an animal model for the human R350P desminopathy, already depicted pre-clinical changes in myofibrillar arrangement and increased fiber bundle stiffness. As the effect of R349P desmin on axial biomechanics in fully differentiated single muscle fibers is unknown, we used our MyoRobot to compare passive visco-elasticity and active contractile biomechanics in single fibers from fast- and slow-twitch muscles from adult to senile mice, hetero- or homozygous for the R349P desmin mutation with wild type littermates. We demonstrate that R349P desmin presence predominantly increased axial stiffness in both muscle types with a pre-aged phenotype over wild type fibers. Axial viscosity and Ca2+-mediated force were largely unaffected. Mutant single fibers showed tendencies towards faster unloaded shortening over wild type fibers. Effects of aging seen in the wild type appeared earlier in the mutant desmin fibers. Our single-fiber experiments, free of extracellular matrix, suggest that compromised muscle biomechanics is not exclusively attributed to fibrosis but also originates from an impaired intermediate filament network.
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Affiliation(s)
- Charlotte Pollmann
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Bavaria, Germany; (C.P.); (B.R.); (G.P.); (O.F.)
| | - Michael Haug
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Bavaria, Germany; (C.P.); (B.R.); (G.P.); (O.F.)
- Graduate School in Advanced Optical Technologies, Paul-Gordan-Str. 6, 91052 Erlangen, Bavaria, Germany
- School of Medical Sciences, University of New South Wales, Wallace Wurth Building, 18 High St, Sydney, NSW 2052, Australia
- Correspondence:
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Bavaria, Germany; (C.P.); (B.R.); (G.P.); (O.F.)
| | - Gerhard Prölß
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Bavaria, Germany; (C.P.); (B.R.); (G.P.); (O.F.)
| | - Thorsten Pöschel
- Institute of Multi Scale Simulation of Particulate Systems, Friedrich-Alexander-University Erlangen-Nürnberg, Nägelbachstr. 49b, 91052 Erlangen, Bavaria, Germany;
| | - Stefan J Rupitsch
- Institute of Sensor Technology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3/5, 91052 Erlangen, Bavaria, Germany;
| | - Christoph S Clemen
- German Aerospace Center (DLR), Institute of Aerospace Medicine, Linder Höhe, 51147 Cologne, North Rhine-Westphalia, Germany;
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Bavaria, Germany;
- Insitute of Vegetative Physiology, Medical Faculty, University of Cologne, Center of Physiology and Pathophysiology, Robert-Koch-Street 39, 50931 Cologne, North Rhine-Westphalia, Germany
| | - Rolf Schröder
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Bavaria, Germany;
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, Bavaria, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Bavaria, Germany; (C.P.); (B.R.); (G.P.); (O.F.)
- Graduate School in Advanced Optical Technologies, Paul-Gordan-Str. 6, 91052 Erlangen, Bavaria, Germany
- School of Medical Sciences, University of New South Wales, Wallace Wurth Building, 18 High St, Sydney, NSW 2052, Australia
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, Bavaria, Germany
- Victor Chang Cardiac Research Institute, Lowy Packer Building, 405 Liverpool St, Sydney, NSW 2010, Australia
- Optical Imaging Centre Erlangen OICE, Cauerstr. 3, 91058 Erlangen, Bavaria, Germany
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16
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Hristu R, Eftimie LG, Stanciu SG, Tranca DE, Paun B, Sajin M, Stanciu GA. Quantitative second harmonic generation microscopy for the structural characterization of capsular collagen in thyroid neoplasms. BIOMEDICAL OPTICS EXPRESS 2018; 9:3923-3936. [PMID: 30338165 PMCID: PMC6191628 DOI: 10.1364/boe.9.003923] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 05/11/2023]
Abstract
Quantitative second harmonic generation microscopy was used to investigate collagen organization in the fibrillar capsules of human benign and malignant thyroid nodules. We demonstrate that the combination of texture analysis and second harmonic generation images of collagen can be used to differentiate between capsules surrounding the thyroid follicular adenoma and papillary carcinoma nodules. Our findings indicate that second harmonic generation microscopy can provide quantitative information about the collagenous capsule surrounding both the thyroid and thyroid nodules, which may complement traditional histopathological examination.
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Affiliation(s)
- Radu Hristu
- Center for Microcopy-Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | - Lucian G Eftimie
- Center for Microcopy-Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
- Central University Emergency Military Hospital, Pathology Department, 134 Calea Plevnei, 010825 Bucharest, Romania
- Carol Davila University of Medicine and Pharmacy, 37 Dionisie Lupu, 030167 Bucharest, Romania
| | - Stefan G Stanciu
- Center for Microcopy-Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | - Denis E Tranca
- Center for Microcopy-Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
| | - Bogdan Paun
- Faculty of Energetics, University Politehnica of Bucharest, 313 Splaiul Independentei, 060042 Bucharest, Romania
- Currently with Faculty of Automation and Computer Science, Technical University of Cluj-Napoca, 26-28 George Baritiu St, 40002 Cluj-Napoca, Romania
| | - Maria Sajin
- Carol Davila University of Medicine and Pharmacy, 37 Dionisie Lupu, 030167 Bucharest, Romania
| | - George A Stanciu
- Center for Microcopy-Microanalysis and Information Processing, University Politehnica of Bucharest, Bucharest, Romania
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17
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Kravic B, Harbauer AB, Romanello V, Simeone L, Vögtle FN, Kaiser T, Straubinger M, Huraskin D, Böttcher M, Cerqua C, Martin ED, Poveda-Huertes D, Buttgereit A, Rabalski AJ, Heuss D, Rudolf R, Friedrich O, Litchfield D, Marber M, Salviati L, Mougiakakos D, Neuhuber W, Sandri M, Meisinger C, Hashemolhosseini S. In mammalian skeletal muscle, phosphorylation of TOMM22 by protein kinase CSNK2/CK2 controls mitophagy. Autophagy 2018; 14:311-335. [PMID: 29165030 DOI: 10.1080/15548627.2017.1403716] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In yeast, Tom22, the central component of the TOMM (translocase of outer mitochondrial membrane) receptor complex, is responsible for the recognition and translocation of synthesized mitochondrial precursor proteins, and its protein kinase CK2-dependent phosphorylation is mandatory for TOMM complex biogenesis and proper mitochondrial protein import. In mammals, the biological function of protein kinase CSNK2/CK2 remains vastly elusive and it is unknown whether CSNK2-dependent phosphorylation of TOMM protein subunits has a similar role as that in yeast. To address this issue, we used a skeletal muscle-specific Csnk2b/Ck2β-conditional knockout (cKO) mouse model. Phenotypically, these skeletal muscle Csnk2b cKO mice showed reduced muscle strength and abnormal metabolic activity of mainly oxidative muscle fibers, which point towards mitochondrial dysfunction. Enzymatically, active muscle lysates from skeletal muscle Csnk2b cKO mice phosphorylate murine TOMM22, the mammalian ortholog of yeast Tom22, to a lower extent than lysates prepared from controls. Mechanistically, CSNK2-mediated phosphorylation of TOMM22 changes its binding affinity for mitochondrial precursor proteins. However, in contrast to yeast, mitochondrial protein import seems not to be affected in vitro using mitochondria isolated from muscles of skeletal muscle Csnk2b cKO mice. PINK1, a mitochondrial health sensor that undergoes constitutive import under physiological conditions, accumulates within skeletal muscle Csnk2b cKO fibers and labels abnormal mitochondria for removal by mitophagy as demonstrated by the appearance of mitochondria-containing autophagosomes through electron microscopy. Mitophagy can be normalized by either introduction of a phosphomimetic TOMM22 mutant in cultured myotubes, or by in vivo electroporation of phosphomimetic Tomm22 into muscles of mice. Importantly, transfection of the phosphomimetic Tomm22 mutant in muscle cells with ablated Csnk2b restored their oxygen consumption rate comparable to wild-type levels. In sum, our data show that mammalian CSNK2-dependent phosphorylation of TOMM22 is a critical switch for mitophagy and reveal CSNK2-dependent physiological implications on metabolism, muscle integrity and behavior.
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Affiliation(s)
- Bojana Kravic
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Angelika B Harbauer
- b Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Biology , University of Freiburg , Germany
| | - Vanina Romanello
- c Department of Biomedical Science , University of Padova , Padova , Italy
| | - Luca Simeone
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - F-Nora Vögtle
- l Institute of Biochemistry and Molecular Biology, ZBMZ, BIOSS (Centre for Biological Signalling Studies), Faculty of Medicine , University of Freiburg , Germany
| | - Tobias Kaiser
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Marion Straubinger
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Danyil Huraskin
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Martin Böttcher
- d Department of Internal Medicine, Hematology and Oncology, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Cristina Cerqua
- e Clinical Genetics Unit, Department of Woman and Child Health , University of Padova, IRP Città della Speranza , Padova , Italy
| | - Eva Denise Martin
- f King's College London BHF Centre of Research Excellence, The Rayne Institute , St Thomas' Hospital , London , United Kingdom
| | - Daniel Poveda-Huertes
- b Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Biology , University of Freiburg , Germany
| | - Andreas Buttgereit
- g Institute of Medical Biotechnology , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | | | - Dieter Heuss
- i Department of Neurology , University Hospital of Erlangen, Medical Faculty, Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Rüdiger Rudolf
- j University of Applied Sciences Mannheim , Mannheim , Germany
| | - Oliver Friedrich
- g Institute of Medical Biotechnology , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | | | - Michael Marber
- f King's College London BHF Centre of Research Excellence, The Rayne Institute , St Thomas' Hospital , London , United Kingdom
| | - Leonardo Salviati
- e Clinical Genetics Unit, Department of Woman and Child Health , University of Padova, IRP Città della Speranza , Padova , Italy
| | - Dimitrios Mougiakakos
- d Department of Internal Medicine, Hematology and Oncology, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Winfried Neuhuber
- k Institute of Anatomy, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
| | - Marco Sandri
- c Department of Biomedical Science , University of Padova , Padova , Italy
| | - Chris Meisinger
- l Institute of Biochemistry and Molecular Biology, ZBMZ, BIOSS (Centre for Biological Signalling Studies), Faculty of Medicine , University of Freiburg , Germany
| | - Said Hashemolhosseini
- a Institute of Biochemistry, Medical Faculty , Friedrich-Alexander-University of Erlangen-Nürnberg , Erlangen , Germany
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18
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Schneidereit D, Nübler S, Prölß G, Reischl B, Schürmann S, Müller OJ, Friedrich O. Optical prediction of single muscle fiber force production using a combined biomechatronics and second harmonic generation imaging approach. LIGHT, SCIENCE & APPLICATIONS 2018; 7:79. [PMID: 30374401 PMCID: PMC6199289 DOI: 10.1038/s41377-018-0080-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/19/2018] [Accepted: 09/24/2018] [Indexed: 05/22/2023]
Abstract
Skeletal muscle is an archetypal organ whose structure is tuned to match function. The magnitude of order in muscle fibers and myofibrils containing motor protein polymers determines the directed force output of the summed force vectors and, therefore, the muscle's power performance on the structural level. Structure and function can change dramatically during disease states involving chronic remodeling. Cellular remodeling of the cytoarchitecture has been pursued using noninvasive and label-free multiphoton second harmonic generation (SHG) microscopy. Hereby, structure parameters can be extracted as a measure of myofibrillar order and thus are suggestive of the force output that a remodeled structure can still achieve. However, to date, the parameters have only been an indirect measure, and a precise calibration of optical SHG assessment for an exerted force has been elusive as no technology in existence correlates these factors. We engineered a novel, automated, high-precision biomechatronics system into a multiphoton microscope allows simultaneous isometric Ca2+-graded force or passive viscoelasticity measurements and SHG recordings. Using this MechaMorph system, we studied force and SHG in single EDL muscle fibers from wt and mdx mice; the latter serves as a model for compromised force and abnormal myofibrillar structure. We present Ca2+-graded isometric force, pCa-force curves, passive viscoelastic parameters and 3D structure in the same fiber for the first time. Furthermore, we provide a direct calibration of isometric force to morphology, which allows noninvasive prediction of the force output of single fibers from only multiphoton images, suggesting a potential application in the diagnosis of myopathies.
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Affiliation(s)
- Dominik Schneidereit
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
| | - Gerhard Prölß
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Sebastian Schürmann
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver J Müller
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, 24105 Kiel, Germany
- DZHK (German Center for Cardiovascular Research) Partner Site Hamburg/Kiel/Lübeck, Kiel, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
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19
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Friedrich O, Diermeier S, Larsson L. Weak by the machines: muscle motor protein dysfunction - a side effect of intensive care unit treatment. Acta Physiol (Oxf) 2018; 222. [PMID: 28387014 DOI: 10.1111/apha.12885] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/12/2017] [Accepted: 04/04/2017] [Indexed: 12/25/2022]
Abstract
Intensive care interventions involve periods of mechanical ventilation, sedation and complete mechanical silencing of patients. Critical illness myopathy (CIM) is an ICU-acquired myopathy that is associated with limb muscle weakness, muscle atrophy, electrical silencing of muscle and motor proteinopathy. The hallmark of CIM is a preferential muscle myosin loss due to increased catabolic and reduced anabolic activity. The ubiquitin proteasome pathway plays an important role, apart from recently identified novel mechanisms affecting non-lysosomal protein degradation or autophagy. CIM is not reproduced by pure disuse atrophy, denervation atrophy, steroid-induced atrophy or septic myopathy, although combinations of high-dose steroids and denervation can mimic CIM. New animal models of critical illness and ICU treatment (i.e. mechanical ventilation and complete immobilization) provide novel insights regarding the time course of protein synthesis and degradation alterations, and the role of protective chaperone activities in the process of myosin loss. Altered mechano-signalling seems involved in triggering a major part of myosin loss in experimental CIM models, and passive loading of muscle potently ameliorates the CIM phenotype. We provide a systematic overview of similarities and distinct differences in the signalling pathways involved in triggering muscle atrophy in CIM and isolated trigger factors. As preferential myosin loss is mostly determined from biochemistry analyses providing no spatial resolution of myosin loss processes within myofibres, we also provide first results monitoring myosin signal intensities during experimental ICU intervention using multi-photon Second Harmonic Generation microscopy. Our results confirm that myosin loss is an evenly distributed process within myofibres rather than being confined to hot spots.
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Affiliation(s)
- O. Friedrich
- Institute of Medical Biotechnology; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Advanced Optical Technologie (SAOT); Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
| | - S. Diermeier
- Institute of Medical Biotechnology; Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
- Erlangen Graduate School in Advanced Optical Technologie (SAOT); Friedrich-Alexander-University Erlangen-Nürnberg; Erlangen Germany
| | - L. Larsson
- Department of Physiology & Pharmacology; Karolinska Institutet; Stockholm Sweden
- Section of Clinical Neurophysiology; Department of Clinical Neuroscience; Karolinska Institutet; Stockholm Sweden
- Department of Biobehavioral Health; The Pennsylvania State University; University Park PA USA
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20
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Diermeier S, Buttgereit A, Schürmann S, Winter L, Xu H, Murphy RM, Clemen CS, Schröder R, Friedrich O. Preaged remodeling of myofibrillar cytoarchitecture in skeletal muscle expressing R349P mutant desmin. Neurobiol Aging 2017; 58:77-87. [PMID: 28715662 DOI: 10.1016/j.neurobiolaging.2017.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/02/2017] [Accepted: 06/06/2017] [Indexed: 12/14/2022]
Abstract
The majority of hereditary and acquired myopathies are clinically characterized by progressive muscle weakness. We hypothesized that ongoing derangement of skeletal muscle cytoarchitecture at the single fiber level may precede and be responsible for the progressive muscle weakness. Here, we analyzed the effects of aging in wild-type (wt) and heterozygous (het) and homozygous (hom) R349P desmin knock-in mice. The latter harbor the ortholog of the most frequently encountered human R350P desmin missense mutation. We quantitatively analyzed the subcellular cytoarchitecture of fast- and slow-twitch muscles from young, intermediate, and aged wt as well as desminopathy mice. We recorded multiphoton second harmonic generation and nuclear fluorescence signals in single muscle fibers to compare aging-related effects in all genotypes. The analysis of wt mice revealed that the myofibrillar cytoarchitecture remained stable with aging in fast-twitch muscles, whereas slow-twitch muscle fibers displayed structural derangements during aging. In contrast, the myofibrillar cytoarchitecture and nuclear density were severely compromised in fast- and slow-twitch muscle fibers of hom R349P desmin mice at all ages. Het mice only showed a clear degradation in their fiber structure in fast-twitch muscles from the adult to the presenescent age bin. Our study documents distinct signs of normal and R349P mutant desmin-related remodeling of the 3D myofibrillar architecture during aging, which provides a structural basis for the progressive muscle weakness.
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Affiliation(s)
- Stefanie Diermeier
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany; SAOT, Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany; Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Andreas Buttgereit
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany; Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Sebastian Schürmann
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany; SAOT, Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany; Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Lilli Winter
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Hongyang Xu
- Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
| | - Robyn M Murphy
- Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
| | - Christoph S Clemen
- Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany; Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany
| | - Rolf Schröder
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany; Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany; SAOT, Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany; Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
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21
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Early signs of architectural and biomechanical failure in isolated myofibers and immortalized myoblasts from desmin-mutant knock-in mice. Sci Rep 2017; 7:1391. [PMID: 28469177 PMCID: PMC5431221 DOI: 10.1038/s41598-017-01485-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/29/2017] [Indexed: 01/25/2023] Open
Abstract
In striated muscle, desmin intermediate filaments interlink the contractile myofibrillar apparatus with mitochondria, nuclei, and the sarcolemma. The desmin network’s pivotal role in myocytes is evident since mutations in the human desmin gene cause severe myopathies and cardiomyopathies. Here, we investigated skeletal muscle pathology in myofibers and myofibrils isolated from young hetero- and homozygous R349P desmin knock-in mice, which carry the orthologue of the most frequent human desmin missense mutation R350P. We demonstrate that mutant desmin alters myofibrillar cytoarchitecture, markedly disrupts the lateral sarcomere lattice and distorts myofibrillar angular axial orientation. Biomechanical assessment revealed a high predisposition to stretch-induced damage in fiber bundles of R349P mice. Notably, Ca2+-sensitivity and passive myofibrillar tension were decreased in heterozygous fiber bundles, but increased in homozygous fiber bundles compared to wildtype mice. In a parallel approach, we generated and subsequently subjected immortalized heterozygous R349P desmin knock-in myoblasts to magnetic tweezer experiments that revealed a significantly increased sarcolemmal lateral stiffness. Our data suggest that mutated desmin already markedly impedes myocyte structure and function at pre-symptomatic stages of myofibrillar myopathies.
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22
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Cully TR, Murphy RM, Roberts L, Raastad T, Fassett RG, Coombes JS, Jayasinghe I, Launikonis BS. Human skeletal muscle plasmalemma alters its structure to change its Ca 2+-handling following heavy-load resistance exercise. Nat Commun 2017; 8:14266. [PMID: 28193999 PMCID: PMC5316829 DOI: 10.1038/ncomms14266] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 12/08/2016] [Indexed: 01/30/2023] Open
Abstract
High-force eccentric exercise results in sustained increases in cytoplasmic Ca2+ levels ([Ca2+]cyto), which can cause damage to the muscle. Here we report that a heavy-load strength training bout greatly alters the structure of the membrane network inside the fibres, the tubular (t-) system, causing the loss of its predominantly transverse organization and an increase in vacuolation of its longitudinal tubules across adjacent sarcomeres. The transverse tubules and vacuoles displayed distinct Ca2+-handling properties. Both t-system components could take up Ca2+ from the cytoplasm but only transverse tubules supported store-operated Ca2+ entry. The retention of significant amounts of Ca2+ within vacuoles provides an effective mechanism to reduce the total content of Ca2+ within the fibre cytoplasm. We propose this ability can reduce or limit resistance exercise-induced, Ca2+-dependent damage to the fibre by the reduction of [Ca2+]cyto to help maintain fibre viability during the period associated with delayed onset muscle soreness.
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Affiliation(s)
- Tanya R. Cully
- School of Biomedical Sciences, The University of Queensland,
Brisbane, Queensland
4072, Australia
| | - Robyn M. Murphy
- Department of Biochemistry & Genetics, La Trobe Institute for
Molecular Science, La Trobe University, Melbourne, Victoria
3086, Australia
| | - Llion Roberts
- School of Human Movement and Nutritional Sciences, The University of
Queensland, Brisbane, Queensland
4072, Australia
- Centre of Excellence for Applied Sport Science Research, Queensland
Academy of Sport, Brisbane, Queensland
4111, Australia
| | - Truls Raastad
- Norwegian School of Sport Sciences, Oslo
N-0806, Norway
| | - Robert G. Fassett
- School of Human Movement and Nutritional Sciences, The University of
Queensland, Brisbane, Queensland
4072, Australia
| | - Jeff S. Coombes
- School of Human Movement and Nutritional Sciences, The University of
Queensland, Brisbane, Queensland
4072, Australia
| | - Izzy Jayasinghe
- School of Biomedical Sciences, The University of Queensland,
Brisbane, Queensland
4072, Australia
- School of Biomedical Sciences, University of Leeds,
Leeds
LS2 9JT, UK
| | - Bradley S. Launikonis
- School of Biomedical Sciences, The University of Queensland,
Brisbane, Queensland
4072, Australia
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23
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Buttgereit A. Second Harmonic Generation Microscopy of Muscle Cell Morphology and Dynamics. Methods Mol Biol 2017; 1601:229-241. [PMID: 28470530 DOI: 10.1007/978-1-4939-6960-9_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Microscopy in combination with contrast-increasing dyes allows the visualization and analysis of organs, tissues, and various cells. Because of their better resolution, the development of confocal and laser microscopes enables the investigations of cell components, which are labeled with fluorescent dyes. The imaging of living cells on subcellular level (also in vivo) needs a labeling by gene transfection of GFP or similar labeled proteins. We present a method for visualization of cell structure in skeletal and heart muscle by label-free Second Harmonic Generation (SHG) microscopy and describe analytic methods for quantitative measurements of morphology and dynamics in skeletal muscle fibers.
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Affiliation(s)
- Andreas Buttgereit
- Institute of Medical Biotechnology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
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24
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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] [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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25
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Förderer M, Georgiev T, Mosqueira M, Fink RHA, Vogel M. Functional second harmonic generation microscopy probes molecular dynamics with high temporal resolution. BIOMEDICAL OPTICS EXPRESS 2016; 7:525-541. [PMID: 26977360 PMCID: PMC4771469 DOI: 10.1364/boe.7.000525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/18/2015] [Accepted: 12/18/2015] [Indexed: 06/05/2023]
Abstract
Second harmonic generation (SHG) microscopy is a powerful tool for label free ex vivo or in vivo imaging, widely used to investigate structure and organization of endogenous SHG emitting proteins such as myosin or collagen. Polarization resolved SHG microscopy renders supplementary information and is used to probe different molecular states. This development towards functional SHG microscopy is calling for new methods for high speed functional imaging of dynamic processes. In this work we present two approaches with linear polarized light and demonstrate high speed line scan measurements of the molecular dynamics of the motor protein myosin with a time resolution of 1 ms in mammalian muscle cells. Such a high speed functional SHG microscopy has high potential to deliver new insights into structural and temporal molecular dynamics under ex vivo or in vivo conditions.
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Affiliation(s)
- Moritz Förderer
- Medical Biophysics Unit, Institute for Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany;
| | - Tihomir Georgiev
- Medical Biophysics Unit, Institute for Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Matias Mosqueira
- Medical Biophysics Unit, Institute for Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Rainer H A Fink
- Medical Biophysics Unit, Institute for Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Martin Vogel
- Medical Biophysics Unit, Institute for Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany; Current address: Max Planck Institute of Biophysics, Frankfurt/Main, Germany;
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26
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Georgiev T, Zapiec B, Förderer M, Fink RHA, Vogel M. Colocalization properties of elementary Ca(2+) release signals with structures specific to the contractile filaments and the tubular system of intact mouse skeletal muscle fibers. J Struct Biol 2015; 192:366-375. [PMID: 26431893 DOI: 10.1016/j.jsb.2015.09.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 09/26/2015] [Accepted: 09/29/2015] [Indexed: 11/19/2022]
Abstract
Ca(2+) regulates several important intracellular processes. We combined second harmonic generation (SHG) and two photon excited fluorescence microscopy (2PFM) to simultaneously record the SHG signal of the myosin filaments and localized elementary Ca(2+) release signals (LCSs). We found LCSs associated with Y-shaped structures of the myosin filament pattern (YMs), so called verniers, in intact mouse skeletal muscle fibers under hypertonic treatment. Ion channels crucial for the Ca(2+) regulation are located in the tubular system, a system that is important for Ca(2+) regulation and excitation-contraction coupling. We investigated the tubular system of intact, living mouse skeletal muscle fibers using 2PFM and the fluorescent Ca(2+) indicator Fluo-4 dissolved in the external solution or the membrane dye di-8-ANEPPS. We simultaneously measured the SHG signal from the myosin filaments of the skeletal muscle fibers. We found that at least a subset of the YMs observed in SHG images are closely juxtaposed with Y-shaped structures of the transverse tubules (YTs). The distances of corresponding YMs and YTs yield values between 1.3 μm and 4.1 μm including pixel uncertainty with a mean distance of 2.52±0.10 μm (S.E.M., n=41). Additionally, we observed that some of the linear-shaped areas in the tubular system are colocalized with linear-shaped areas in the SHG images.
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Affiliation(s)
- Tihomir Georgiev
- Medical Biophysics, Institute of Physiology and Pathophysiology, Ruprecht Karls Universität, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany.
| | - Bolek Zapiec
- Medical Biophysics, Institute of Physiology and Pathophysiology, Ruprecht Karls Universität, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany; Max Planck Research Unit for Neurogenetics, 60438 Frankfurt am Main, Germany
| | - Moritz Förderer
- Medical Biophysics, Institute of Physiology and Pathophysiology, Ruprecht Karls Universität, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany
| | - Rainer H A Fink
- Medical Biophysics, Institute of Physiology and Pathophysiology, Ruprecht Karls Universität, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany
| | - Martin Vogel
- Medical Biophysics, Institute of Physiology and Pathophysiology, Ruprecht Karls Universität, Im Neuenheimer Feld 326, 69120 Heidelberg, Germany; Max Planck Research Unit for Neurogenetics, 60438 Frankfurt am Main, Germany.
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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] [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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28
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Recher G, Coumailleau P, Rouède D, Tiaho F. Structural origin of the drastic modification of second harmonic generation intensity pattern occurring in tail muscles of climax stages xenopus tadpoles. J Struct Biol 2015; 190:1-10. [PMID: 25770062 DOI: 10.1016/j.jsb.2015.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 02/08/2015] [Accepted: 03/04/2015] [Indexed: 01/27/2023]
Abstract
Second harmonic generation (SHG) microscopy is a powerful tool for studying submicron architecture of muscles tissues. Using this technique, we show that the canonical single frequency sarcomeric SHG intensity pattern (SHG-IP) of premetamorphic xenopus tadpole tail muscles is converted to double frequency (2f) sarcomeric SHG-IP in metamorphic climax stages due to massive physiological muscle proteolysis. This conversion was found to rise from 7% in premetamorphic muscles to about 97% in fragmented muscular apoptotic bodies. Moreover a 66% conversion was also found in non-fragmented metamorphic tail muscles. Also, a strong correlation between predominant 2f sarcomeric SHG-IPs and myofibrillar misalignment is established with electron microscopy. Experimental and theoretical results demonstrate the higher sensitivity and the supra resolution power of SHG microscopy over TPEF to reveal 3D myofibrillar misalignment. From this study, we suggest that 2f sarcomeric SHG-IP could be used as signature of triad defect and disruption of excitation-contraction coupling. As the mechanism of muscle proteolysis is similar to that found in mdx mouse muscles, we further suggest that xenopus tadpole tail resorption at climax stages could be used as an alternative or complementary model of Duchene muscular dystrophy.
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Affiliation(s)
- Gaëlle Recher
- UMR CNRS 6026, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France; Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK
| | - Pascal Coumailleau
- UMR CNRS 6026, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France; IRSET, INSERM, U1085, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France
| | - Denis Rouède
- IPR, CNRS, UMR-CNRS UR1-6251, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France
| | - François Tiaho
- UMR CNRS 6026, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France; IRSET, INSERM, U1085, Université de Rennes1, Campus de Beaulieu, Rennes F-35000, France.
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Buttgereit A, Weber C, Friedrich O. A novel quantitative morphometry approach to assess regeneration in dystrophic skeletal muscle. Neuromuscul Disord 2014; 24:596-603. [DOI: 10.1016/j.nmd.2014.04.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 04/23/2014] [Indexed: 11/16/2022]
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30
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Friedrich O. ‘Set the controls…’ - phenotype matching beyond genetics in muscular dystrophy. Exp Physiol 2014; 99:638-9. [DOI: 10.1113/expphysiol.2014.077933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Oliver Friedrich
- Friedrich-Alexander-University Erlangen-Nuremberg; Institute of Medical Biotechnology; Erlangen Germany
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