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Desmin Knock-Out Cardiomyopathy: A Heart on the Verge of Metabolic Crisis. Int J Mol Sci 2022; 23:ijms231912020. [PMID: 36233322 PMCID: PMC9570457 DOI: 10.3390/ijms231912020] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 09/30/2022] [Accepted: 10/02/2022] [Indexed: 12/05/2022] Open
Abstract
Desmin mutations cause familial and sporadic cardiomyopathies. In addition to perturbing the contractile apparatus, both desmin deficiency and mutated desmin negatively impact mitochondria. Impaired myocardial metabolism secondary to mitochondrial defects could conceivably exacerbate cardiac contractile dysfunction. We performed metabolic myocardial phenotyping in left ventricular cardiac muscle tissue in desmin knock-out mice. Our analyses revealed decreased mitochondrial number, ultrastructural mitochondrial defects, and impaired mitochondria-related metabolic pathways including fatty acid transport, activation, and catabolism. Glucose transporter 1 and hexokinase-1 expression and hexokinase activity were increased. While mitochondrial creatine kinase expression was reduced, fetal creatine kinase expression was increased. Proteomic analysis revealed reduced expression of proteins involved in electron transport mainly of complexes I and II, oxidative phosphorylation, citrate cycle, beta-oxidation including auxiliary pathways, amino acid catabolism, and redox reactions and oxidative stress. Thus, desmin deficiency elicits a secondary cardiac mitochondriopathy with severely impaired oxidative phosphorylation and fatty and amino acid metabolism. Increased glucose utilization and fetal creatine kinase upregulation likely portray attempts to maintain myocardial energy supply. It may be prudent to avoid medications worsening mitochondrial function and other metabolic stressors. Therapeutic interventions for mitochondriopathies might also improve the metabolic condition in desmin deficient hearts.
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Langer HT, Mossakowski AA, Avey AM, Wohlgemuth RP, Smith LR, Zbinden-Foncea H, Baar K. A mutation in desmin makes skeletal muscle less vulnerable to acute muscle damage after eccentric loading in rats. FASEB J 2021; 35:e21860. [PMID: 34411340 PMCID: PMC9292853 DOI: 10.1096/fj.202100711rr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/15/2021] [Accepted: 08/02/2021] [Indexed: 01/23/2023]
Abstract
Desminopathy is the most common intermediate filament disease in humans. The most frequent mutation causing desminopathy in patients is a R350P DES missense mutation. We have developed a rat model with an analogous mutation in R349P Des. To investigate the role of R349P Des in mechanical loading, we stimulated the sciatic nerve of wild‐type littermates (WT) (n = 6) and animals carrying the mutation (MUT) (n = 6) causing a lengthening contraction of the dorsi flexor muscles. MUT animals showed signs of ongoing regeneration at baseline as indicated by a higher number of central nuclei (genotype: P < .0001). While stimulation did not impact central nuclei, we found an increased number of IgG positive fibers (membrane damage indicator) after eccentric contractions with both genotypes (stimulation: P < .01). Interestingly, WT animals displayed a more pronounced increase in IgG positive fibers with stimulation compared to MUT (interaction: P < .05). In addition to altered histology, molecular signaling on the protein level differed between WT and MUT. The membrane repair protein dysferlin decreased with eccentric loading in WT but increased in MUT (interaction: P < .05). The autophagic substrate p62 was increased in both genotypes with loading (stimulation: P < .05) but tended to be more elevated in WT (interaction: P = .05). Caspase 3 levels, a central regulator of apoptotic cell death, was increased with stimulation in both genotypes (stimulation: P < .01) but more so in WT animals (interaction: P < .0001). Overall, our data indicate that R349P Des rats have a lower susceptibility to structural muscle damage of the cytoskeleton and sarcolemma with acute eccentric loading.
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Affiliation(s)
- Henning T Langer
- Functional Molecular Biology Laboratory, Department of Physiology and Membrane Biology, University of California, Davis, California, USA
| | - Agata A Mossakowski
- Neurobiology, Physiology and Behavior, University of California, Davis, California, USA.,Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Alec M Avey
- Neurobiology, Physiology and Behavior, University of California, Davis, California, USA
| | - Ross P Wohlgemuth
- Neurobiology, Physiology and Behavior, University of California, Davis, California, USA
| | - Lucas R Smith
- Neurobiology, Physiology and Behavior, University of California, Davis, California, USA
| | - Herman Zbinden-Foncea
- Exercise Physiology Laboratory, School of Kinesiology, Universidad Finis Terrae, Santiago, Chile
| | - Keith Baar
- Functional Molecular Biology Laboratory, Department of Physiology and Membrane Biology, University of California, Davis, California, USA.,Neurobiology, Physiology and Behavior, University of California, Davis, California, USA.,VA Northern California Health Care System, Mather, California, USA
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3
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Haug M, Ritter P, Michael M, Reischl B, Schurmann S, Prols G, Friedrich O. Structure-Function Relationships in Muscle Fibres: MyoRobot online Assessment of Muscle Fibre Elasticity and Sarcomere Length Distributions. IEEE Trans Biomed Eng 2021; 69:148-155. [PMID: 34133271 DOI: 10.1109/tbme.2021.3089739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Muscle biomechanics is set by the spacing of repetitive striation patterns of individual sarcomeres within single muscle fibres of stacked myofibrils. Sarcomere lengths (SL) are rather unequally distributed than of equal distance. This non-uniformity may affect both, force production as well as passive-elastic deformation. However, online recording of SL during axially imposed strains is cumbersome due to a lack of compact technologies. METHODS To fuse SL pattern recognition with restoration force assessments during quasi-static axial stretch, we implemented live tracking of SL distributions simultaneous to voice-coil actuated stretch and restoration force recordings in our MyoRobot 2.0 automated biomechatronics platform. Both were obtained online during stretchrelaxation cycles of murine single muscle fibres. RESULTS Under quasi-static stretch conditions (∼1 μm/s fibre length changes), almost no apparent hysteresis was detected in single fibres. SL showed a non-uniform distribution. While mean SL varied between 2.6 μm and 3.4 μm upon 140% stretch, two populations of fibres were noticed: one showing a minor change in SL distribution with stretch, and one becoming more equally distributed upon stretch. CONCLUSION A roughly 5% SL variability under rest either diminishes or remains almost unaltered upon elastic axial deformation. This may reflect differential impact of mostly extra-sarcomeric components to stretch in this stretch range. SIGNIFICANCE The augmented functionality of the MyoRobot 2.0 towards online sarcomere analyses within single fibres shall provide a valuable tool for the muscle community to study the contribution of serial elastic and force producing elements in health and disease models.
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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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AAV-mediated cardiac gene transfer of wild-type desmin in mouse models for recessive desminopathies. Gene Ther 2020; 27:516-524. [PMID: 32322014 PMCID: PMC7674151 DOI: 10.1038/s41434-020-0147-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/25/2020] [Accepted: 03/30/2020] [Indexed: 11/23/2022]
Abstract
Mutations in the human desmin gene cause autosomal-dominant and recessive cardiomyopathies and myopathies with marked phenotypic variability. Here, we investigated the effects of adeno-associated virus (AAV)-mediated cardiac wild-type desmin expression in homozygous desmin knockout (DKO) and homozygous R349P desmin knockin (DKI) mice. These mice serve as disease models for two subforms of autosomal-recessive desminopathies, the former for the one with a complete lack of desmin protein and the latter for the one with solely mutant desmin protein expression in conjunction with protein aggregation pathology in striated muscle. Two-month-old mice were injected with either a single dose of 5 × 1012 AAV9-hTNT2-mDes (AAV-Des) vector genomes or NaCl as control. One week after injection, mice were subjected to a forced swimming exercise protocol for 4 weeks. Cardiac function was monitored over a period of 15 month after injection and before the mice were sacrificed for biochemical and morphological analysis. AAV-mediated cardiac expression of wild-type desmin in both the homozygous DKO and DKI backgrounds reached levels seen in wild-type mice. Notably, AAV-Des treated DKO mice showed a regular subcellular distribution of desmin as well as a normalization of functional and morphological cardiac parameters. Treated DKI mice, however, showed an aberrant subcellular localization of desmin, unchanged functional cardiac parameters, and a trend toward an increased cardiac fibrosis. In conclusion, the effect of a high-dose AAV9-based desmin gene therapy is highly beneficial for the heart in DKO animals, but not in DKI mice.
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Stöckigt F, Eichhorn L, Beiert T, Knappe V, Radecke T, Steinmetz M, Nickenig G, Peeva V, Kudin AP, Kunz WS, Berwanger C, Kamm L, Schultheis D, Schlötzer-Schrehardt U, Clemen CS, Schröder R, Schrickel JW. Heart failure after pressure overload in autosomal-dominant desminopathies: Lessons from heterozygous DES-p.R349P knock-in mice. PLoS One 2020; 15:e0228913. [PMID: 32126091 PMCID: PMC7053759 DOI: 10.1371/journal.pone.0228913] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/27/2020] [Indexed: 11/21/2022] Open
Abstract
Background Mutations in the human desmin gene (DES) cause autosomal-dominant and -recessive cardiomyopathies, leading to heart failure, arrhythmias, and AV blocks. We analyzed the effects of vascular pressure overload in a patient-mimicking p.R349P desmin knock-in mouse model that harbors the orthologue of the frequent human DES missense mutation p.R350P. Methods and results Transverse aortic constriction (TAC) was performed on heterozygous (HET) DES-p.R349P mice and wild-type (WT) littermates. Echocardiography demonstrated reduced left ventricular ejection fraction in HET-TAC (WT-sham: 69.5 ± 2.9%, HET-sham: 64.5 ± 4.7%, WT-TAC: 63.5 ± 4.9%, HET-TAC: 55.7 ± 5.4%; p<0.01). Cardiac output was significantly reduced in HET-TAC (WT sham: 13088 ± 2385 μl/min, HET sham: 10391 ± 1349μl/min, WT-TAC: 8097 ± 1903μl/min, HET-TAC: 5793 ± 2517μl/min; p<0.01). Incidence and duration of AV blocks as well as the probability to induce ventricular tachycardias was highest in HET-TAC. We observed reduced mtDNA copy numbers in HET-TAC (WT-sham: 12546 ± 406, HET-sham: 13526 ± 781, WT-TAC: 11155 ± 3315, HET-TAC: 8649 ± 1582; p = 0.025), but no mtDNA deletions. The activity of respiratory chain complexes I and IV showed the greatest reductions in HET-TAC. Conclusion Pressure overload in HET mice aggravated the clinical phenotype of cardiomyopathy and resulted in mitochondrial dysfunction. Preventive avoidance of pressure overload/arterial hypertension in desminopathy patients might represent a crucial therapeutic measure.
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Affiliation(s)
- Florian Stöckigt
- Department of Cardiology, University Hospital Bonn, Bonn, Germany
- Department of Cardiology, Krankenhaus Porz, Urbacher Weg, Cologne, Germany
- * E-mail:
| | - Lars Eichhorn
- Department of Anesthesiology, University Hospital Bonn, Bonn, Germany
| | - Thomas Beiert
- Department of Cardiology, University Hospital Bonn, Bonn, Germany
| | - Vincent Knappe
- Department of Cardiology, University Hospital Bonn, Bonn, Germany
| | - Tobias Radecke
- Department of Cardiology, University Hospital Essen, Hufelandstraße, Essen, Germany
| | - Martin Steinmetz
- Department of Cardiology, University Hospital Essen, Hufelandstraße, Essen, Germany
| | - Georg Nickenig
- Department of Cardiology, University Hospital Bonn, Bonn, Germany
| | - Viktoriya Peeva
- Institute of Experimental Epileptology and Cognition Research, Bonn, Germany
- Department of Epileptology, University Hospital of Bonn, Bonn, Germany
| | - Alexei P. Kudin
- Institute of Experimental Epileptology and Cognition Research, Bonn, Germany
- Department of Epileptology, University Hospital of Bonn, Bonn, Germany
| | - Wolfram S. Kunz
- Institute of Experimental Epileptology and Cognition Research, Bonn, Germany
- Department of Epileptology, University Hospital of Bonn, Bonn, Germany
| | - Carolin Berwanger
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Linder Höhe, Cologne, Germany
| | - Lisa Kamm
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage, Erlangen, Germany
| | - Dorothea Schultheis
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage, Erlangen, Germany
| | - Ursula Schlötzer-Schrehardt
- Department of Opthalmology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage, Erlangen, Germany
| | - Christoph S. Clemen
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Linder Höhe, Cologne, Germany
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage, Erlangen, Germany
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
- Center for Physiology and Pathophysiology, Institute of Vegetative Physiology, Medical Faculty, University of Cologne, Cologne, Germany
| | - Rolf Schröder
- Institute of Neuropathology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage, Erlangen, Germany
| | - Jan W. Schrickel
- Department of Cardiology, University Hospital Bonn, Bonn, Germany
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MyoRobot 2.0: An advanced biomechatronics platform for automated, environmentally controlled skeletal muscle single fiber biomechanics assessment employing inbuilt real-time optical imaging. Biosens Bioelectron 2019; 138:111284. [DOI: 10.1016/j.bios.2019.04.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 04/24/2019] [Indexed: 11/23/2022]
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The MyoRobot technology discloses a premature biomechanical decay of skeletal muscle fiber bundles derived from R349P desminopathy mice. Sci Rep 2019; 9:10769. [PMID: 31341183 PMCID: PMC6656739 DOI: 10.1038/s41598-019-46723-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 07/03/2019] [Indexed: 01/05/2023] Open
Abstract
Mutations in the Des gene coding for the muscle-specific intermediate filament protein desmin lead to myopathies and cardiomyopathies. We previously generated a R349P desmin knock-in mouse strain as a patient-mimicking model for the corresponding most frequent human desmin mutation R350P. Since nothing is known about the age-dependent changes in the biomechanics of affected muscles, we investigated the passive and active biomechanics of small fiber bundles from young (17–23 wks), adult (25–45 wks) and aged (>60 wks) heterozygous and homozygous R349P desmin knock-in mice in comparison to wild-type littermates. We used a novel automated biomechatronics platform, the MyoRobot, to perform coherent quantitative recordings of passive (resting length-tension curves, visco-elasticity) and active (caffeine-induced force transients, pCa-force, ‘slack-tests’) parameters to determine age-dependent effects of the R349P desmin mutation in slow-twitch soleus and fast-twitch extensor digitorum longus small fiber bundles. We demonstrate that active force properties are not affected by this mutation while passive steady-state elasticity is vastly altered in R349P desmin fiber bundles compatible with a pre-aged phenotype exhibiting stiffer muscle preparations. Visco-elasticity on the other hand, was not altered. Our study represents the first systematic age-related characterization of small muscle fiber bundle preparation biomechanics in conjunction with inherited desminopathy.
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9
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Winter L, Unger A, Berwanger C, Spörrer M, Türk M, Chevessier F, Strucksberg KH, Schlötzer-Schrehardt U, Wittig I, Goldmann WH, Marcus K, Linke WA, Clemen CS, Schröder R. Imbalances in protein homeostasis caused by mutant desmin. Neuropathol Appl Neurobiol 2018; 45:476-494. [PMID: 30179276 DOI: 10.1111/nan.12516] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 08/17/2018] [Indexed: 12/19/2022]
Abstract
AIMS We investigated newly generated immortalized heterozygous and homozygous R349P desmin knock-in myoblasts in conjunction with the corresponding desminopathy mice as models for desminopathies to analyse major protein quality control processes in response to the presence of R349P mutant desmin. METHODS We used hetero- and homozygous R349P desmin knock-in mice for analyses and for crossbreeding with p53 knock-out mice to generate immortalized R349P desmin knock-in skeletal muscle myoblasts and myotubes. Skeletal muscle sections and cultured muscle cells were investigated by indirect immunofluorescence microscopy, proteasomal activity measurements and immunoblotting addressing autophagy rate, chaperone-assisted selective autophagy and heat shock protein levels. Muscle sections were further analysed by transmission and immunogold electron microscopy. RESULTS We demonstrate that mutant desmin (i) increases proteasomal activity, (ii) stimulates macroautophagy, (iii) dysregulates the chaperone assisted selective autophagy and (iv) elevates the protein levels of αB-crystallin and Hsp27. Both αB-crystallin and Hsp27 as well as Hsp90 displayed translocation patterns from Z-discs as well as Z-I junctions, respectively, to the level of sarcomeric I-bands in dominant and recessive desminopathies. CONCLUSIONS Our findings demonstrate that the presence of R349P mutant desmin causes a general imbalance in skeletal muscle protein homeostasis via aberrant activity of all major protein quality control systems. The augmented activity of these systems and the subcellular shift of essential heat shock proteins may deleteriously contribute to the previously observed increased turnover of desmin itself and desmin-binding partners, which triggers progressive dysfunction of the extrasarcomeric cytoskeleton and the myofibrillar apparatus in the course of the development of desminopathies.
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Affiliation(s)
- L Winter
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany.,Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | - A Unger
- Department of Cardiovascular Physiology, Ruhr-University Bochum, Bochum, Germany.,Institute for Genetics of Heart Diseases, University Hospital Münster, Münster, Germany
| | - C Berwanger
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany.,Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - M Spörrer
- Center for Medical Physics and Technology, Biophysics Group, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - M Türk
- Department of Neurology, University Hospital Erlangen, Erlangen, Germany
| | - F Chevessier
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - K-H Strucksberg
- Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | | | - I Wittig
- Functional Proteomics, SFB815 Core Unit, Medical School, Goethe University, Frankfurt, Germany
| | - W H Goldmann
- Center for Medical Physics and Technology, Biophysics Group, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - K Marcus
- Medizinisches Proteom-Center, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - W A Linke
- Department of Cardiovascular Physiology, Ruhr-University Bochum, Bochum, Germany.,Institute of Physiology II, University of Münster, Münster, Germany
| | - C S Clemen
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany.,Center for Biochemistry, Institute of Biochemistry I, Medical Faculty, University of Cologne, Cologne, Germany
| | - R Schröder
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany
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10
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Brodehl A, Gaertner-Rommel A, Milting H. Molecular insights into cardiomyopathies associated with desmin (DES) mutations. Biophys Rev 2018; 10:983-1006. [PMID: 29926427 DOI: 10.1007/s12551-018-0429-0] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 05/22/2018] [Indexed: 12/15/2022] Open
Abstract
Increasing usage of next-generation sequencing techniques pushed during the last decade cardiogenetic diagnostics leading to the identification of a huge number of genetic variants in about 170 genes associated with cardiomyopathies, channelopathies, or syndromes with cardiac involvement. Because of the biochemical and cellular complexity, it is challenging to understand the clinical meaning or even the relevant pathomechanisms of the majority of genetic sequence variants. However, detailed knowledge about the associated molecular pathomechanism is essential for the development of efficient therapeutic strategies in future and genetic counseling. Mutations in DES, encoding the muscle-specific intermediate filament protein desmin, have been identified in different kinds of cardiac and skeletal myopathies. Here, we review the functions of desmin in health and disease with a focus on cardiomyopathies. In addition, we will summarize the genetic and clinical literature about DES mutations and will explain relevant cell and animal models. Moreover, we discuss upcoming perspectives and consequences of novel experimental approaches like genome editing technology, which might open a novel research field contributing to the development of efficient and mutation-specific treatment options.
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Affiliation(s)
- Andreas Brodehl
- Erich and Hanna Klessmann Institute for Cardiovascular Research & Development, Heart and Diabetes Centre NRW, Ruhr-University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany.
| | - Anna Gaertner-Rommel
- Erich and Hanna Klessmann Institute for Cardiovascular Research & Development, Heart and Diabetes Centre NRW, Ruhr-University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Hendrik Milting
- Erich and Hanna Klessmann Institute for Cardiovascular Research & Development, Heart and Diabetes Centre NRW, Ruhr-University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany.
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11
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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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The MyoRobot: A novel automated biomechatronics system to assess voltage/Ca 2+ biosensors and active/passive biomechanics in muscle and biomaterials. Biosens Bioelectron 2017; 102:589-599. [PMID: 29245144 DOI: 10.1016/j.bios.2017.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 11/11/2017] [Accepted: 12/05/2017] [Indexed: 11/21/2022]
Abstract
We engineered an automated biomechatronics system, MyoRobot, for robust objective and versatile assessment of muscle or polymer materials (bio-)mechanics. It covers multiple levels of muscle biosensor assessment, e.g. membrane voltage or contractile apparatus Ca2+ ion responses (force resolution 1µN, 0-10mN for the given sensor; [Ca2+] range ~ 100nM-25µM). It replaces previously tedious manual protocols to obtain exhaustive information on active/passive biomechanical properties across various morphological tissue levels. Deciphering mechanisms of muscle weakness requires sophisticated force protocols, dissecting contributions from altered Ca2+ homeostasis, electro-chemical, chemico-mechanical biosensors or visco-elastic components. From whole organ to single fibre levels, experimental demands and hardware requirements increase, limiting biomechanics research potential, as reflected by only few commercial biomechatronics systems that can address resolution, experimental versatility and mostly, automation of force recordings. Our MyoRobot combines optical force transducer technology with high precision 3D actuation (e.g. voice coil, 1µm encoder resolution; stepper motors, 4µm feed motion), and customized control software, enabling modular experimentation packages and automated data pre-analysis. In small bundles and single muscle fibres, we demonstrate automated recordings of (i) caffeine-induced-, (ii) electrical field stimulation (EFS)-induced force, (iii) pCa-force, (iv) slack-tests and (v) passive length-tension curves. The system easily reproduces results from manual systems (two times larger stiffness in slow over fast muscle) and provides novel insights into unloaded shortening velocities (declining with increasing slack lengths). The MyoRobot enables automated complex biomechanics assessment in muscle research. Applications also extend to material sciences, exemplarily shown here for spider silk and collagen biopolymers.
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