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Jorgenson KW, Hibbert JE, Sayed RKA, Lange AN, Godwin JS, Mesquita PHC, Ruple BA, McIntosh MC, Kavazis AN, Roberts MD, Hornberger TA. A novel imaging method (FIM-ID) reveals that myofibrillogenesis plays a major role in the mechanically induced growth of skeletal muscle. eLife 2024; 12:RP92674. [PMID: 38466320 PMCID: PMC10928493 DOI: 10.7554/elife.92674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024] Open
Abstract
An increase in mechanical loading, such as that which occurs during resistance exercise, induces radial growth of muscle fibers (i.e. an increase in cross-sectional area). Muscle fibers are largely composed of myofibrils, but whether radial growth is mediated by an increase in the size of the myofibrils (i.e. myofibril hypertrophy) and/or the number of myofibrils (i.e. myofibrillogenesis) is not known. Electron microscopy (EM) can provide images with the level of resolution that is needed to address this question, but the acquisition and subsequent analysis of EM images is a time- and cost-intensive process. To overcome this, we developed a novel method for visualizing myofibrils with a standard fluorescence microscope (fluorescence imaging of myofibrils with image deconvolution [FIM-ID]). Images from FIM-ID have a high degree of resolution and contrast, and these properties enabled us to develop pipelines for automated measurements of myofibril size and number. After extensively validating the automated measurements, we used both mouse and human models of increased mechanical loading to discover that the radial growth of muscle fibers is largely mediated by myofibrillogenesis. Collectively, the outcomes of this study offer insight into a fundamentally important topic in the field of muscle growth and provide future investigators with a time- and cost-effective means to study it.
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Affiliation(s)
- Kent W Jorgenson
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin-MadisonMadisonUnited States
| | - Jamie E Hibbert
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin-MadisonMadisonUnited States
| | - Ramy KA Sayed
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin-MadisonMadisonUnited States
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag UniversitySohagEgypt
| | - Anthony N Lange
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin-MadisonMadisonUnited States
| | | | | | | | | | | | | | - Troy A Hornberger
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin-MadisonMadisonUnited States
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Jorgenson KW, Hibbert JE, Sayed RKA, Lange AN, Godwin JS, Mesquita PHC, Ruple BA, McIntosh MC, Kavazis AN, Roberts MD, Hornberger TA. A Novel Imaging Method (FIM-ID) Reveals that Myofibrillogenesis Plays a Major Role in the Mechanically Induced Growth of Skeletal Muscle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.13.557204. [PMID: 37745462 PMCID: PMC10515927 DOI: 10.1101/2023.09.13.557204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
An increase in mechanical loading, such as that which occurs during resistance exercise, induces radial growth of muscle fibers (i.e., an increase in cross-sectional area). Muscle fibers are largely composed of myofibrils, but whether radial growth is mediated by an increase in the size of the myofibrils (i.e., myofibril hypertrophy) and/or the number of myofibrils (i.e., myofibrillogenesis) is not known. Electron microscopy (EM) can provide images with the level of resolution that is needed to address this question, but the acquisition and subsequent analysis of EM images is a time- and cost-intensive process. To overcome this, we developed a novel method for visualizing myofibrils with a standard fluorescence microscope (FIM-ID). Images from FIM-ID have a high degree of resolution and contrast, and these properties enabled us to develop pipelines for automated measurements of myofibril size and number. After extensively validating the automated measurements, we used both mouse and human models of increased mechanical loading to discover that the radial growth of muscle fibers is largely mediated by myofibrillogenesis. Collectively, the outcomes of this study offer insight into a fundamentally important topic in the field of muscle growth and provide future investigators with a time- and cost-effective means to study it.
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3
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Kinney CJ, O'Neill A, Noland K, Huang W, Muriel J, Lukyanenko V, Kane MA, Ward CW, Collier AF, Roche JA, McLenithan JC, Reed PW, Bloch RJ. μ-Crystallin in Mouse Skeletal Muscle Promotes a Shift from Glycolytic toward Oxidative Metabolism. Curr Res Physiol 2021; 4:47-59. [PMID: 34746826 PMCID: PMC8562245 DOI: 10.1016/j.crphys.2021.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/31/2021] [Accepted: 02/04/2021] [Indexed: 01/24/2023] Open
Abstract
μ-Crystallin, encoded by the CRYM gene, binds the thyroid hormones, T3 and T4. Because T3 and T4 are potent regulators of metabolism and gene expression, and CRYM levels in human skeletal muscle can vary widely, we investigated the effects of overexpression of Crym. We generated transgenic mice, Crym tg, that expressed Crym protein specifically in skeletal muscle at levels 2.6-147.5 fold higher than in controls. Muscular functions, Ca2+ transients, contractile force, fatigue, running on treadmills or wheels, were not significantly altered, although T3 levels in tibialis anterior (TA) muscle were elevated ~190-fold and serum T4 was decreased 1.2-fold. Serum T3 and thyroid stimulating hormone (TSH) levels were unaffected. Crym transgenic mice studied in metabolic chambers showed a significant decrease in the respiratory exchange ratio (RER) corresponding to a 13.7% increase in fat utilization as an energy source compared to controls. Female but not male Crym tg mice gained weight more rapidly than controls when fed high fat or high simple carbohydrate diets. Although labeling for myosin heavy chains showed no fiber type differences in TA or soleus muscles, application of machine learning algorithms revealed small but significant morphological differences between Crym tg and control soleus fibers. RNA-seq and gene ontology enrichment analysis showed a significant shift towards genes associated with slower muscle function and its metabolic correlate, β-oxidation. Protein expression showed a similar shift, though with little overlap. Our study shows that μ-crystallin plays an important role in determining substrate utilization in mammalian muscle and that high levels of μ-crystallin are associated with a shift toward greater fat metabolism.
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Affiliation(s)
- Christian J. Kinney
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Andrea O'Neill
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Kaila Noland
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Weiliang Huang
- Department of Pharmaceutical Sciences School of Pharmacy, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Joaquin Muriel
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Valeriy Lukyanenko
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Maureen A. Kane
- Department of Pharmaceutical Sciences School of Pharmacy, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Christopher W. Ward
- Department of Orthopedics School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Alyssa F. Collier
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Joseph A. Roche
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - John C. McLenithan
- Department of Medicine School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Patrick W. Reed
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
| | - Robert J. Bloch
- Department of Physiology School of Medicine, University of Maryland Baltimore, Baltimore, MD, 21201, USA
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An X, Ogawa-Wong A, Carmody C, Ambrosio R, Cicatiello AG, Luongo C, Salvatore D, Handy DE, Larsen PR, Wajner SM, Dentice M, Zavacki AM. A Type 2 Deiodinase-Dependent Increase in Vegfa Mediates Myoblast-Endothelial Cell Crosstalk During Skeletal Muscle Regeneration. Thyroid 2021; 31:115-127. [PMID: 32787533 PMCID: PMC7840309 DOI: 10.1089/thy.2020.0291] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Background: The type 2 deiodinase (DIO2) converts thyroxine to 3,3',5-triiodothyronine (T3), modulating intracellular T3. An increase in DIO2 within muscle stem cells during skeletal muscle regeneration leads to T3-dependent potentiation of differentiation. The muscle stem cell niche comprises numerous cell types, which coordinate the regeneration process. For example, muscle stem cells provide secretory signals stimulating endothelial cell-mediated vascular repair, and, in turn, endothelial cells promote muscle stem differentiation. We hypothesized that Dio2 loss in muscle stem cells directly impairs muscle stem cell-endothelial cell communication, leading to downstream disruption of endothelial cell function. Methods: We assessed the production of proangiogenic factors in differentiated C2C12 cells and in a C2C12 cell line without Dio2 (D2KO C2C12) by real-time quantitative-polymerase chain reaction and enzyme-linked immunosorbent assay. Conditioned medium (CM) was collected daily in parallel to evaluate its effects on human umbilical vein endothelial cell (HUVEC) proliferation, migration and chemotaxis, and vascular network formation. The effects of T3-treatment on vascular endothelial growth factor (Vegfa) mRNA expression in C2C12 cells and mouse muscle were assessed. Chromatin immunoprecipitation (ChIP) identified thyroid hormone receptor (TR) binding to the Vegfa gene. Using mice with a targeted disruption of Dio2 (D2KO mice), we determined endothelial cell number by immunohistochemistry/flow cytometry and evaluated related gene expression in both uninjured and injured skeletal muscle. Results: In differentiated D2KO C2C12 cells, Vegfa expression was 46% of wildtype (WT) C2C12 cells, while secreted VEGF was 45%. D2KO C2C12 CM exhibited significantly less proangiogenic effects on HUVECs. In vitro and in vivo T3 treatment of C2C12 cells and WT mice, and ChIP using antibodies against TRα, indicated that Vegfa is a direct genomic T3 target. In uninjured D2KO soleus muscle, Vegfa expression was decreased by 28% compared with WT mice, while endothelial cell numbers were decreased by 48%. Seven days after skeletal muscle injury, D2KO mice had 36% fewer endothelial cells, coinciding with an 83% decrease in Vegfa expression in fluorescence-activated cell sorting purified muscle stem cells. Conclusion:Dio2 loss in the muscle stem cell impairs muscle stem cell-endothelial cell crosstalk via changes in the T3-responsive gene Vegfa, leading to downstream impairment of endothelial cell function both in vitro and in vivo.
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Affiliation(s)
- Xingxing An
- Key Laboratory of Transplant Engineering and Immunology, Department of Endocrinology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Ashley Ogawa-Wong
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Colleen Carmody
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | | | | | - Cristina Luongo
- Department of Public Health, University of Naples “Federico II,” Naples, Italy
| | - Domenico Salvatore
- Department of Public Health, University of Naples “Federico II,” Naples, Italy
- CEINGE-Biotecnologie Avanzate Scarl, Naples, Italy
| | - Diane E. Handy
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - P. Reed Larsen
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Simone Magagnin Wajner
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
- Endocrine Division, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Monica Dentice
- Department of Clinical Medicine and Surgery and University of Naples “Federico II,” Naples, Italy
| | - Ann Marie Zavacki
- Division of Endocrinology, Diabetes, and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Kerp H, Engels K, Kramer F, Doycheva D, Sebastian Hönes G, Zwanziger D, Christian Moeller L, Heuer H, Führer D. Age effect on thyroid hormone brain response in male mice. Endocrine 2019; 66:596-606. [PMID: 31494803 DOI: 10.1007/s12020-019-02078-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 08/29/2019] [Indexed: 02/06/2023]
Abstract
PURPOSE Thyroid hormones (TH) are important for brain development and central nervous system (CNS) function. Disturbances of thyroid function occur with higher prevalence in the ageing population and may negatively impact brain function. METHODS We investigated the age impact on behavior in young adult and old male mice (5 vs. 20 months) with chronic hypo- or hyper-thyroidism as well as in sham-treated controls. Expression of TH transporters and TH responsive genes was studied in CNS and pituitary by in situ hybridization and qRT-PCR, whereas TH serum concentrations were determined by immunoassay. RESULTS Serum TH levels were lower in old compared with young hyperthyroid mice, suggesting a milder hyperthyroid phenotype in the aged group. Likewise, elevated plus maze activity was reduced in old hyperthyroid animals. Under hypothyroid conditions, thyroxine serum concentrations did not differ in young and old mice. Both groups showed a comparable decline in activity and elevated anxiety levels. However, an attenuated increase in hypothalamic thyrotropin releasing hormone and pituitary thyroid stimulating hormone transcript expression was found in old hypothyroid mice. Brain expression of monocarboxylate transporter 8 and organic anion transporting polypeptide 1c1 was not affected by age or TH status. CONCLUSIONS In summary, ageing attenuates neurological phenotypes in hyperthyroid but not hypothyroid mice, which fits with age effects on TH serum levels in the animals. In contrast no changes in TH transporter expression were found in aged mouse brains with hyper- or hypo-thyroid state.
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Affiliation(s)
- Helena Kerp
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
| | - Kathrin Engels
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
| | - Frederike Kramer
- Leibniz Institute on Aging/Fritz Lipmann Institute (FLI), 07745, Jena, Germany
| | - Denica Doycheva
- Leibniz Institute on Aging/Fritz Lipmann Institute (FLI), 07745, Jena, Germany
| | - Georg Sebastian Hönes
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
| | - Denise Zwanziger
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
| | - Lars Christian Moeller
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
| | - Heike Heuer
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany
- Leibniz Institute on Aging/Fritz Lipmann Institute (FLI), 07745, Jena, Germany
| | - Dagmar Führer
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, 45122, Essen, Germany.
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Carmody C, Ogawa-Wong AN, Martin C, Luongo C, Zuidwijk M, Sager B, Petersen T, Roginski Guetter A, Janssen R, Wu EY, Bogaards S, Neumann NM, Hau K, Marsili A, Boelen A, Silva JE, Dentice M, Salvatore D, Wagers AJ, Larsen PR, Simonides WS, Zavacki AM. A Global Loss of Dio2 Leads to Unexpected Changes in Function and Fiber Types of Slow Skeletal Muscle in Male Mice. Endocrinology 2019; 160:1205-1222. [PMID: 30951174 PMCID: PMC6482039 DOI: 10.1210/en.2019-00088] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 03/29/2019] [Indexed: 12/20/2022]
Abstract
The type 2 iodothyronine-deiodinase (D2) enzyme converts T4 to T3, and mice deficient in this enzyme [D2 knockout (D2KO) mice] have decreased T3 derived from T4 in skeletal muscle despite normal circulating T3 levels. Because slow skeletal muscle is particularly susceptible to changes in T3 levels, we expected D2 inactivation to result in more pronounced slow-muscle characteristics in the soleus muscle, mirroring hypothyroidism. However, ex vivo studies of D2KO soleus revealed higher rates of twitch contraction and relaxation and reduced resistance to fatigue. Immunostaining of D2KO soleus showed that these properties were associated with changes in muscle fiber type composition, including a marked increase in the number of fast, glycolytic type IIB fibers. D2KO soleus muscle fibers had a larger cross-sectional area, and this correlated with increased myonuclear accretion in myotubes formed from D2KO skeletal muscle precursor cells differentiated in vitro. Consistent with our functional findings, D2KO soleus gene expression was markedly different from that in hypothyroid wild-type (WT) mice. Comparison of gene expression between euthyroid WT and D2KO mice indicated that PGC-1α, a T3-dependent regulator of slow muscle fiber type, was decreased by ∼50% in D2KO soleus. Disruption of Dio2 in the C2C12 myoblast cell line led to a significant decrease in PGC-1α expression and a faster muscle phenotype upon differentiation. These results indicate that D2 loss leads to significant changes in soleus contractile function and fiber type composition that are inconsistent with local hypothyroidism and suggest that reduced levels of PCG-1α may contribute to the observed phenotypical changes.
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Affiliation(s)
| | | | | | - Cristina Luongo
- Brigham and Women’s Hospital, Boston, Massachusetts
- University of Naples “Federico II,” Napoli, Italy
| | - Marian Zuidwijk
- Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | | | | | | | - Rob Janssen
- Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | | | - Sylvia Bogaards
- Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | | | - Kaman Hau
- Brigham and Women’s Hospital, Boston, Massachusetts
| | | | - Anita Boelen
- Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - J Enrique Silva
- Baystate Medical Center, Springfield, Massachusetts
- Tufts University School of Medicine, Boston, Massachusetts
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7
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Ruiz A, Dror E, Handschin C, Furrer R, Perez-Schindler J, Bachmann C, Treves S, Zorzato F. Over-expression of a retinol dehydrogenase (SRP35/DHRS7C) in skeletal muscle activates mTORC2, enhances glucose metabolism and muscle performance. Sci Rep 2018; 8:636. [PMID: 29330505 PMCID: PMC5766524 DOI: 10.1038/s41598-017-18844-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/18/2017] [Indexed: 12/31/2022] Open
Abstract
SRP-35 is a short-chain dehydrogenase/reductase belonging to the DHRS7C dehydrogenase/ reductase family 7. Here we show that its over-expression in mouse skeletal muscles induces enhanced muscle performance in vivo, which is not related to alterations in excitation-contraction coupling but rather linked to enhanced glucose metabolism. Over-expression of SRP-35 causes increased phosphorylation of AktS473, triggering plasmalemmal targeting of GLUT4 and higher glucose uptake into muscles. SRP-35 signaling involves RARα and RARγ (non-genomic effect), PI3K and mTORC2. We also demonstrate that all-trans retinoic acid, a downstream product of the enzymatic activity of SRP-35, mimics the effect of SRP-35 in skeletal muscle, inducing a synergistic effect with insulin on AKTS473 phosphorylation. These results indicate that SRP-35 affects skeletal muscle metabolism and may represent an important target for the treatment of metabolic diseases.
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Affiliation(s)
- Alexis Ruiz
- Departments of Anesthesia and of Biomedicine, Basel University Hospital, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Erez Dror
- Max Planck Institute of Immunobiology and Epigenetics, 79108, Freiburg, Germany
| | | | - Regula Furrer
- Biozentrum, University of Basel, CH-4056, Basel, Switzerland
| | | | - Christoph Bachmann
- Departments of Anesthesia and of Biomedicine, Basel University Hospital, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Susan Treves
- Departments of Anesthesia and of Biomedicine, Basel University Hospital, Hebelstrasse 20, 4031, Basel, Switzerland.,Department of Life Sciences, General Pathology section, University of Ferrara, Via Borsari 46, 44100, Ferrara, Italy
| | - Francesco Zorzato
- Departments of Anesthesia and of Biomedicine, Basel University Hospital, Hebelstrasse 20, 4031, Basel, Switzerland. .,Department of Life Sciences, General Pathology section, University of Ferrara, Via Borsari 46, 44100, Ferrara, Italy.
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8
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Dulloo AG, Miles-Chan JL, Montani JP, Schutz Y. Isometric thermogenesis at rest and during movement: a neglected variable in energy expenditure and obesity predisposition. Obes Rev 2017; 18 Suppl 1:56-64. [PMID: 28164457 DOI: 10.1111/obr.12505] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 12/01/2016] [Indexed: 12/01/2022]
Abstract
Isometric thermogenesis as applied to human energy expenditure refers to heat production resulting from increased muscle tension. While most physical activities consist of both dynamic and static (isometric) muscle actions, the isometric component is very often essential for the optimal performance of dynamic work given its role in coordinating posture during standing, walking and most physical activities of everyday life. Over the past 75 years, there has been sporadic interest into the relevance of isometric work to thermoregulatory thermogenesis and to adaptive thermogenesis pertaining to body-weight regulation. This has been in relation to (i) a role for skeletal muscle minor tremor or microvibration - nowadays referred to as 'resting muscle mechanical activity' - in maintaining body temperature in response to mild cooling; (ii) a role for slowed skeletal muscle isometric contraction-relaxation cycle as a mechanism for energy conservation in response to caloric restriction and weight loss and (iii) a role for spontaneous physical activity (which is contributed importantly by isometric work for posture maintenance and fidgeting behaviours) in adaptive thermogenesis pertaining to weight regulation. This paper reviews the evidence underlying these proposed roles for isometric work in adaptive thermogenesis and highlights the contention that variability in this neglected component of energy expenditure could contribute to human predisposition to obesity.
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Affiliation(s)
- A G Dulloo
- Department of Medicine, Division of Physiology, University of Fribourg, Fribourg, Switzerland
| | - J L Miles-Chan
- Department of Medicine, Division of Physiology, University of Fribourg, Fribourg, Switzerland
| | - J-P Montani
- Department of Medicine, Division of Physiology, University of Fribourg, Fribourg, Switzerland
| | - Y Schutz
- Department of Medicine, Division of Physiology, University of Fribourg, Fribourg, Switzerland
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9
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Organ JM, Srisuwananukorn A, Price P, Joll JE, Biro KC, Rupert JE, Chen NX, Avin KG, Moe SM, Allen MR. Reduced skeletal muscle function is associated with decreased fiber cross-sectional area in the Cy/+ rat model of progressive kidney disease. Nephrol Dial Transplant 2015; 31:223-30. [PMID: 26442903 DOI: 10.1093/ndt/gfv352] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 09/08/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The combination of skeletal muscle wasting and compromised function plays a role in the health decline commonly observed in chronic kidney disease (CKD) patients, but the pathophysiology of muscle mass/strength changes remains unclear. The purpose of this study was to characterize muscle properties in the Cy/+ rat model of spontaneously progressive CKD. METHODS Leg muscle function and serum biochemistry of male Cy/+ (CKD) rats and their nonaffected littermates (NLs) were assessed in vivo at 25, 30 and 35 weeks of age. Architecture and histology of extensor digitorum longus (EDL) and soleus (SOL) muscles were assessed ex vivo at the conclusion of the experiment. We tested the hypothesis that animals with CKD have progressive loss of muscle function, and that this functional deficit is associated with loss of muscle mass and quality. RESULTS Thirty-five-week-old CKD rats produced significantly lower maximum torque in ankle dorsiflexion and shorter time to maximum torque, and longer half relaxation time in dorsiflexion and plantarflexion compared with NL rats. Peak dorsiflexion torque (but not plantarflexion torque) in CKD remained steady from 25 to 35 weeks, while in NL rats, peak torque increased. Mass, physiologic cross-sectional area (CSA) and fiber-type (myosin heavy chain isoform) proportions of EDL and SOL were not different between CKD and NL. However, the EDL of CKD rats showed reduced CSAs in all fiber types, while only MyHC-1 fibers were decreased in area in the SOL. CONCLUSIONS The results of this study demonstrate that muscle function progressively declines in the Cy/+ rat model of CKD. Because whole muscle mass and architecture do not vary between CKD and NL, but CKD muscles show reduction in individual fiber CSA, our data suggest that the functional decline is related to increased muscle fiber atrophy.
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Affiliation(s)
- Jason M Organ
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Andrew Srisuwananukorn
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Paige Price
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jeffery E Joll
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kelly C Biro
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Joseph E Rupert
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Neal X Chen
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Keith G Avin
- Department of Physical Therapy, Indiana University School of Health and Rehabilitation Science, Indianapolis, IN, USA
| | - Sharon M Moe
- Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA Roudebush Veterans Affairs Medical Center, Indianapolis, IN, USA
| | - Matthew R Allen
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
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10
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De Andrade PBM, Neff LA, Strosova MK, Arsenijevic D, Patthey-Vuadens O, Scapozza L, Montani JP, Ruegg UT, Dulloo AG, Dorchies OM. Caloric restriction induces energy-sparing alterations in skeletal muscle contraction, fiber composition and local thyroid hormone metabolism that persist during catch-up fat upon refeeding. Front Physiol 2015; 6:254. [PMID: 26441673 PMCID: PMC4584973 DOI: 10.3389/fphys.2015.00254] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Accepted: 08/28/2015] [Indexed: 11/18/2022] Open
Abstract
Weight regain after caloric restriction results in accelerated fat storage in adipose tissue. This catch-up fat phenomenon is postulated to result partly from suppressed skeletal muscle thermogenesis, but the underlying mechanisms are elusive. We investigated whether the reduced rate of skeletal muscle contraction-relaxation cycle that occurs after caloric restriction persists during weight recovery and could contribute to catch-up fat. Using a rat model of semistarvation-refeeding, in which fat recovery is driven by suppressed thermogenesis, we show that contraction and relaxation of leg muscles are slower after both semistarvation and refeeding. These effects are associated with (i) higher expression of muscle deiodinase type 3 (DIO3), which inactivates tri-iodothyronine (T3), and lower expression of T3-activating enzyme, deiodinase type 2 (DIO2), (ii) slower net formation of T3 from its T4 precursor in muscles, and (iii) accumulation of slow fibers at the expense of fast fibers. These semistarvation-induced changes persisted during recovery and correlated with impaired expression of transcription factors involved in slow-twitch muscle development. We conclude that diminished muscle thermogenesis following caloric restriction results from reduced muscle T3 levels, alteration in muscle-specific transcription factors, and fast-to-slow fiber shift causing slower contractility. These energy-sparing effects persist during weight recovery and contribute to catch-up fat.
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Affiliation(s)
- Paula B M De Andrade
- Department of Medicine, Physiology, University of Fribourg Fribourg, Switzerland
| | - Laurence A Neff
- Pharmaceutical Biochemistry, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
| | - Miriam K Strosova
- Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
| | - Denis Arsenijevic
- Department of Medicine, Physiology, University of Fribourg Fribourg, Switzerland
| | - Ophélie Patthey-Vuadens
- Pharmaceutical Biochemistry, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland ; Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
| | - Leonardo Scapozza
- Pharmaceutical Biochemistry, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
| | - Jean-Pierre Montani
- Department of Medicine, Physiology, University of Fribourg Fribourg, Switzerland
| | - Urs T Ruegg
- Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
| | - Abdul G Dulloo
- Department of Medicine, Physiology, University of Fribourg Fribourg, Switzerland
| | - Olivier M Dorchies
- Pharmaceutical Biochemistry, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland ; Pharmacology, Geneva-Lausanne School of Pharmaceutical Sciences, University of Geneva, University of Lausanne Geneva, Switzerland
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11
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Zhang D, Wang X, Li Y, Zhao L, Lu M, Yao X, Xia H, Wang YC, Liu MF, Jiang J, Li X, Ying H. Thyroid hormone regulates muscle fiber type conversion via miR-133a1. ACTA ACUST UNITED AC 2014; 207:753-66. [PMID: 25512392 PMCID: PMC4274265 DOI: 10.1083/jcb.201406068] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Thyroid hormone promotes slow-to-fast muscle fiber type conversion by inducing miR-133a1 and thereby repressing the expression of the slow muscle determinant TEAD1. It is known that thyroid hormone (TH) is a major determinant of muscle fiber composition, but the molecular mechanism by which it does so remains unclear. Here, we demonstrated that miR-133a1 is a direct target gene of TH in muscle. Intriguingly, miR-133a, which is enriched in fast-twitch muscle, regulates slow-to-fast muscle fiber type conversion by targeting TEA domain family member 1 (TEAD1), a key regulator of slow muscle gene expression. Inhibition of miR-133a in vivo abrogated TH action on muscle fiber type conversion. Moreover, TEAD1 overexpression antagonized the effect of miR-133a as well as TH on muscle fiber type switch. Additionally, we demonstrate that TH negatively regulates the transcription of myosin heavy chain I indirectly via miR-133a/TEAD1. Collectively, we propose that TH inhibits the slow muscle phenotype through a novel epigenetic mechanism involving repression of TEAD1 expression via targeting by miR-133a1. This identification of a TH-regulated microRNA therefore sheds new light on how TH achieves its diverse biological activities.
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Affiliation(s)
- Duo Zhang
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China
| | - Xiaoyun Wang
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China
| | - Yuying Li
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China
| | - Lei Zhao
- Department of Neuromuscular Disease, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Minghua Lu
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, and Clinical Research Center of Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xuan Yao
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China
| | - Hongfeng Xia
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China
| | - Yu-Cheng Wang
- Department of Nutrition, Shanghai Xuhui Central Hospital, Shanghai 200031, China
| | - Mo-Fang Liu
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, and Clinical Research Center of Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jingjing Jiang
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Xihua Li
- Department of Neuromuscular Disease, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Hao Ying
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; and Center for RNA Research, State Key Laboratory of Molecular Biology; University of Chinese Academy of Sciences, Shanghai 200031, China Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 100021, China Shanghai Key Laboratory of Molecular Andrology, Institute of Biochemistry and Cell Biology, and Clinical Research Center of Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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12
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Shortt CM, Fredsted A, Bradford A, O'Halloran KD. Diaphragm muscle remodeling in a rat model of chronic intermittent hypoxia. J Histochem Cytochem 2013; 61:487-99. [PMID: 23640977 DOI: 10.1369/0022155413490947] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Respiratory muscle remodeling occurs in human sleep apnea--a common respiratory disorder characterized by chronic intermittent hypoxia (CIH) due to recurrent apnea during sleep. We sought to determine if CIH causes remodeling in rat sternohyoid (upper airway dilator) and diaphragm muscles. Adult male Wistar rats were exposed to CIH (n=8), consisting of 90 sec of hypoxia (5% at the nadir; SaO₂ ~80%)/90 sec of normoxia, 8 hr per day, for 7 consecutive days. Sham animals (n=8) were exposed to alternating air/air cycles in parallel. The effect of CIH on myosin heavy-chain (MHC) isoform (1, 2a, 2x, 2b) distribution, sarcoplasmic reticulum calcium ATPase (SERCA) isoform distribution, succinate dehydrogenase activity, glycerol phosphate dehydrogenase activity, and Na⁺/K⁺ ATPase pump content was determined. Sternohyoid muscle structure was unaffected by CIH treatment. CIH did not alter oxidative/glycolytic capacity or the Na⁺/K⁺-ATPase pump content of the diaphragm. CIH significantly increased the areal density of MHC 2b fibers in the rat diaphragm, and this was associated with a shift in SERCA proteins from SERCA2 to SERCA1. We conclude that CIH causes a slow-to-fast fiber transition in the rat diaphragm after just 7 days of treatment. Respiratory muscle functional remodeling may drive aberrant functional plasticity such as decreased muscle endurance, which is a feature of human sleep apnea.
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Affiliation(s)
- Christine M Shortt
- UCD School of Medicine and Medical Science, University College Dublin, Dublin, Ireland.
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13
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Liu M, Yue Y, Li D, Duan D. Catalase overexpression does not impair extensor digitorum longus muscle function in normal mice. Muscle Nerve 2008; 36:833-41. [PMID: 17696155 DOI: 10.1002/mus.20874] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Catalase is a major antioxidant enzyme. Increasing catalase expression represents a promising avenue to improve muscle function in certain physiological conditions and in some muscle diseases. We hypothesized that catalase overexpression should not impair normal muscle contraction. We delivered a hemagglutinin (HA)-tagged human catalase gene to normal mouse muscle by an adeno-associated viral vector (AAV). Western blot and immunostaining revealed efficient expression of HA-tagged catalase. Enzymatic assay demonstrated an approximately threefold increase in catalase activity in AAV-infected muscles. Catalase overexpression impaired neither twitch nor tetanic tension in the extensor digitorum longus (EDL) muscle. Furthermore, EDL fatigue response was not altered. Taken together, we have developed a novel AAV vector to enhance catalase expression. Lack of apparent toxicity in normal muscle strongly supports further exploration of this vector to reduce oxidative stress-induced muscle damage.
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Affiliation(s)
- Mingju Liu
- Department of Molecular Microbiology and Immunology, University of Missouri, School of Medicine, Columbia, Missouri 65212, USA
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14
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Simonides WS, van Hardeveld C. Thyroid hormone as a determinant of metabolic and contractile phenotype of skeletal muscle. Thyroid 2008; 18:205-16. [PMID: 18279021 DOI: 10.1089/thy.2007.0256] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Skeletal muscles are composed of several types of fibers with different contractile and metabolic properties. Genetic background and type of innervation of the fibers primarily determine these properties, but thyroid hormone (TH) is a powerful modulator of the fiber phenotype. The rates of contraction and relaxation are stimulated by TH, as are the energy consumption and heat production associated with activity. Quantitative and qualitative changes in substrate metabolism accommodate the increase in ATP turnover. Because of the total mass of skeletal muscle, these changes affect whole-body physiology. Although apparently straightforward, the phenotypic shifts induced by TH are highly complex and fiber specific. This review addresses the mechanisms by which TH may modulate fiber gene expression and discusses some of the implications of the TH-regulated changes in metabolic and contractile phenotype of skeletal muscle.
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Affiliation(s)
- Warner S Simonides
- Laboratory for Physiology, Institute for Cardiovascular Research VU University Medical Center, Amsterdam, The Netherlands.
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15
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Moncayo R, Moncayo H. A musculoskeletal model of low grade connective tissue inflammation in patients with thyroid associated ophthalmopathy (TAO): the WOMED concept of lateral tension and its general implications in disease. BMC Musculoskelet Disord 2007; 8:17. [PMID: 17319961 PMCID: PMC1820789 DOI: 10.1186/1471-2474-8-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Accepted: 02/23/2007] [Indexed: 12/16/2022] Open
Abstract
Background Low level connective tissue inflammation has been proposed to play a role in thyroid associated ophthalmopathy (TAO). The aim of this study was to investigate this postulate by a musculoskeletal approach together with biochemical parameters. Methods 13 patients with TAO and 16 controls were examined. Erythrocyte levels of Zn, Cu, Ca2+, Mg, and Fe were determined. The musculoskeletal evaluation included observational data on body posture with emphasis on the orbit-head region. The angular foot position in the frontal plane was quantified following gait observation. The axial orientation of the legs and feet was evaluated in an unloaded supine position. Functional propioceptive tests based on stretch stimuli were done by using foot inversion and foot rotation. Results Alterations in the control group included neck tilt in 3 cases, asymmetrical foot angle during gait in 2, and a reaction to foot inversion in 5 cases. TAO patients presented facial asymmetry with displaced eye fissure inclination (mean 9.1°) as well as tilted head-on-neck position (mean 5.7°). A further asymmetry feature was external rotation of the legs and feet (mean 27°). Both foot inversion as well as foot rotation induced a condition of neuromuscular deficit. This condition could be regulated by gentle acupressure either on the lateral abdomen or the lateral ankle at the acupuncture points gall bladder 26 or bladder 62, respectively. In 5 patients, foot rotation produced a phenomenon of moving toes in the contra lateral foot. In addition foot rotation was accompanied by an audible tendon snapping. Lower erythrocyte Zn levels and altered correlations between Ca2+, Mg, and Fe were found in TAO. Conclusion This whole body observational study has revealed axial deviations and body asymmetry as well as the phenomenon of moving toes in TAO. The most common finding was an arch-like displacement of the body, i.e. eccentric position, with foot inversion and head tilt to the contra lateral side and tendon snapping. We propose that eccentric muscle action over time can be the basis for a low grade inflammatory condition. The general implications of this model and its relations to Zn and Se will be discussed.
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Affiliation(s)
- Roy Moncayo
- WOMED, Karl-Kapferer-Strasse 5, A-6020 Innsbruck, Austria
| | - Helga Moncayo
- WOMED, Karl-Kapferer-Strasse 5, A-6020 Innsbruck, Austria
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16
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Miyabara EH, Aoki MS, Soares AG, Saltao RM, Vilicev CM, Passarelli M, Scanlan TS, Gouveia CH, Moriscot AS. Thyroid hormone receptor-β-selective agonist GC-24 spares skeletal muscle type I to II fiber shift. Cell Tissue Res 2005; 321:233-41. [PMID: 15947969 DOI: 10.1007/s00441-005-1119-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Accepted: 03/09/2005] [Indexed: 10/25/2022]
Abstract
Triiodothyronine (T3) is known to play a key role in the function of several tissues/organs via the thyroid hormone receptor isoforms alpha (TRalpha) and beta (TRbeta). We have investigated the effects of GC-24, a novel synthetic TRbeta-selective compound, on skeletal muscle fiber-type determination, cross-sectional area, and gene expression in rat skeletal muscles. For fiber typing, cross sections of soleus and extensor digitorum longus (EDL) muscles were stained for myosin ATPase activity at various pHs. Serum T3, T4, and cholesterol levels were also determined. Analysis of highly T3-responsive genes, viz., myosin heavy chain IIa (MHCIIa) and sarcoendoplasmic reticulum adenosine triphosphatase (SERCA1), was performed by quantitative real-time polymerase chain reaction. Equimolar doses of T3 and GC-24 had a similar cholesterol-lowering effect. T3, but not GC-24, decreased fiber type I and increased fiber type II abundance in soleus and EDL muscles. Conversely, in EDL, both T3 and GC-24 decreased the mean cross-sectional area of type I fibers. MHCIIa gene expression was reduced (approximately 50%) by T3 and unchanged by GC-24. SERCA1 gene expression was strongly induced by T3 (approximately 20-fold) and mildly induced by GC-24 (approximately two-fold). These results show that GC-24 does not significantly alter the composition of skeletal muscle fiber type and further strengthens the putative use of GC compounds as therapeutic agents.
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MESH Headings
- Acetates/pharmacology
- Acetates/therapeutic use
- Animals
- Benzhydryl Compounds/pharmacology
- Benzhydryl Compounds/therapeutic use
- Calcium-Transporting ATPases/genetics
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cell Size/drug effects
- Cholesterol/metabolism
- Gene Expression/drug effects
- Gene Expression/physiology
- Muscle Fibers, Fast-Twitch/drug effects
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle Fibers, Slow-Twitch/drug effects
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Myosin Heavy Chains/genetics
- Phenotype
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Sarcoplasmic Reticulum Calcium-Transporting ATPases
- Thyroid Hormone Receptors beta/agonists
- Thyroid Hormone Receptors beta/metabolism
- Triiodothyronine/adverse effects
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Affiliation(s)
- Elen H Miyabara
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Brazil
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17
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Holmberg K, Kuteeva E, Brumovsky P, Kahl U, Karlström H, Lucas GA, Rodriguez J, Westerblad H, Hilke S, Theodorsson E, Berge OG, Lendahl U, Bartfai T, Hökfelt T. Generation and phenotypic characterization of a galanin overexpressing mouse. Neuroscience 2005; 133:59-77. [PMID: 15893631 DOI: 10.1016/j.neuroscience.2005.01.062] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Revised: 01/18/2005] [Accepted: 01/26/2005] [Indexed: 11/25/2022]
Abstract
In most parts of the peripheral nervous system galanin is expressed at very low levels. To further understand the functional role of galanin, a mouse overexpressing galanin under the platelet-derived growth factor-B was generated, and high levels of galanin expression were observed in several peripheral tissues and spinal cord. Thus, a large proportion of neurons in autonomic and sensory ganglia were galanin-positive, as were most spinal motor neurons. Strong galanin-like immunoreactivity was also seen in nerve terminals in the corresponding target tissues, including skin, blood vessels, sweat and salivary glands, motor end-plates and the gray matter of the spinal cord. In transgenic superior cervical ganglia around half of all neuron profiles expressed galanin mRNA but axotomy did not cause a further increase, even if mRNA levels were increased in individual neurons. In transgenic dorsal root ganglia galanin mRNA was detected in around two thirds of all neuron profiles, including large ones, and after axotomy the percentage of galanin neuron profiles was similar in overexpressing and wild type mice. Axotomy reduced the total number of DRG neurons less in overexpressing than in wild type mice, indicating a modest rescue effect. Aging by itself increased galanin expression in the superior cervical ganglion in wild type and transgenic mice, and in the latter also in preganglionic cholinergic neurons projecting to the superior cervical ganglion. Galanin overexpressing mice showed an attenuated plasma extravasation, an increased pain response in the formalin test, and changes in muscle physiology, but did not differ from wild type mice in sudomotor function. These findings suggest that overexpressed galanin in some tissues of these mice can be released and via a receptor-mediated action influence pathophysiological processes.
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Affiliation(s)
- K Holmberg
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, B3-4, SE-171 77 Stockholm, Sweden
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