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de Jesus K, de Jesus K, Mourão L, Roesler H, Fernandes RJ, Vaz MAP, Vilas-Boas JP, Machado LJ. Swimmers' Effective Actions during the Backstroke Start Technique. Sensors (Basel) 2023; 23:7723. [PMID: 37765782 PMCID: PMC10538122 DOI: 10.3390/s23187723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/30/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023]
Abstract
The analysis of the external forces of swimming starts has revealed how swimmers propel themselves out of the block, but data should be properly interpreted to fully understand force-generation mechanisms. This study aimed to assess horizontal and vertical forces in the backstroke start based on swimmers' structural and propulsive actions. Firstly, a simulated structural force was estimated by two transient backstroke-start inter-segmental realistic body positions: a maximally tucked position and an extended one (just before the hands-off and the take-off, respectively). Secondly, 10 competitive backstroke swimmers performed four 15 m maximal backstroke starts with the external forces estimated. Thirdly, the simulated structural force was subtracted from raw horizontal and vertical force data, measured between hands-off and take-off instants, resulting in the propulsive forces. The application of the algorithm has evidenced that backstrokers' horizontal and vertical simulated-structural-force components contributed to ~40% of total force during start propulsion (~0.2-0.12 s before the take-off), followed by the propulsive horizontal force increment and a progressive vertical component reduction (~0.05 s) with ~20° take-off angle. Based on these findings, researchers and coaches can better guide swimmers as to the proper mechanical strategies to achieve effectiveness in the backstroke start, and to improve direct transfer of resistance training programs.
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Affiliation(s)
- Karla de Jesus
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Human Studies Development Laboratory, Faculty of Physical Education and Physiotherapy, Federal University of Amazonas, Manaus 69077-000, AM, Brazil
| | - Kelly de Jesus
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Human Studies Development Laboratory, Faculty of Physical Education and Physiotherapy, Federal University of Amazonas, Manaus 69077-000, AM, Brazil
| | - Luís Mourão
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Polytechnic Institute of Porto School of Engineering, 4249-015 Porto, Portugal
| | - Hélio Roesler
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Aquatic Biomechanics Research Laboratory, Health and Sports Science Centre, University of the State of Santa Catarina, Florianópolis 88080-350, SC, Brazil
| | - Ricardo J. Fernandes
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal;
| | - Mário A. P. Vaz
- Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal;
- Institute of Mechanical Engineering and Industrial Management, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal
| | - João Paulo Vilas-Boas
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal;
| | - Leandro J. Machado
- Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, 4200-450 Porto, Portugal; (K.d.J.); (L.M.); (H.R.); (R.J.F.); (J.P.V.-B.); (L.J.M.)
- Porto Biomechanics Laboratory, University of Porto, 4200-450 Porto, Portugal;
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Shi J, Wada M. Effects of eccentric contraction on force enhancement in rat fast-twitch muscle. Physiol Rep 2023; 11:e15797. [PMID: 37731168 PMCID: PMC10511694 DOI: 10.14814/phy2.15797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/08/2023] [Accepted: 08/08/2023] [Indexed: 09/22/2023] Open
Abstract
The aim of this study was to elucidate the effects of eccentric contraction (ECC) on force enhancement in rat fast-twitch skeletal muscle. Gastrocnemius (GAS) muscles were subjected to 200 ECCs in situ by electrical stimulation. Immediately before and after the stimulation, isometric torque produced by ankle flexion was measured at an ankle angle of 90°. After the second torque measurement, the superficial regions of the muscles were dissected and subjected to biochemical and skinned fiber analysis. ECC did not induce changes in the amount of degraded titin. After ECC, isometric torques in the GAS muscles were markedly reduced, especially at low stimulation frequency. ECC increased passive torque in whole muscle and passive force in skinned fibers. Passive force enhancement and the ratio of passive force to the maximal Ca2+ -activated force, but not residual force enhancement, were augmented in the skinned fibers subjected to ECC. An ECC-induced increase in titin-based stiffness may contribute to the increased PFE. These results suggest that skeletal muscle is endowed with a force potentiation system that can attenuate ECC-induced force reductions.
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Affiliation(s)
- Jiayu Shi
- Faculty of Sports SciencesNingbo UniversityZhejiangChina
| | - Masanobu Wada
- Graduate School of Humanities and Social SciencesHiroshima UniversityHiroshimaJapan
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Shi J, Watanabe D, Wada M. Eccentric muscle contraction potentiates titin stiffness-related contractile properties in rat fast-twitch muscles. J Appl Physiol (1985) 2022; 133:710-720. [PMID: 35981734 DOI: 10.1152/japplphysiol.00327.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study was conducted to examine the effects of an acute bout of eccentric muscle contraction (ECC) on titin stiffness-related contractile properties in rat fast-twitch skeletal muscles. Intact gastrocnemius muscles were electrically stimulated in situ to undergo 200-repeated ECCs. Immediately after cessation of the stimulation, the superficial regions of the muscles were dissected and subjected to biochemical and skinned fiber analyses. Small heat shock protein αB-crystallin in the muscle fraction enriched for myofibrillar proteins was increased by ECC. ECC resulted in an increase in the titin-based passive force. Protein kinase A-treatment decreased the passive force only in ECC-subjected but not in rested fibers. ECC decreased the maximum Ca2+-activated force at a sarcomere length (SL) of 2.4 μm and had no effect on myofibrillar-Ca2+ sensitivity at 2.6-μm SL. In both rested and ECC-subjected fibers, these two variables were higher at 3.0-μm SL than at 2.4- or 2.6-μm SL. The differences in the two variables between the short and long SLs were greater in ECC-subjected than in rested fibers. These results indicate that an acute bout of ECC potentiates titin-based passive force, maximum active force at long SLs, and length-dependent activation and suggest that this potentiation may resist muscle fatigue in the muscles of the exercising body.
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Affiliation(s)
- Jiayu Shi
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | - Daiki Watanabe
- Graduate School of Humanities and Social Sciences, Hiroshima University, Hiroshima, Japan
| | - Masanobu Wada
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan.,Graduate School of Humanities and Social Sciences, Hiroshima University, Hiroshima, Japan
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Shi J, Watanabe D, Wada M. Effects of vigorous isometric muscle contraction on titin stiffness-related contractile properties in rat fast-twitch muscles. Am J Physiol Regul Integr Comp Physiol 2021; 321:R858-R868. [PMID: 34668430 DOI: 10.1152/ajpregu.00189.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/13/2021] [Indexed: 12/30/2022]
Abstract
This study was conducted to examine the effects of an acute bout of vigorous isometric contractions on titin stiffness-related contractile properties in rat fast-twitch skeletal muscles. Intact gastrocnemius muscles were electrically stimulated in situ until the force was reduced to ∼50% of the initial force. Immediately after cessation of the stimulation, the superficial regions of the muscles were dissected and subjected to biochemical and skinned fiber analyses. The stimulation resulted in a decrease in the titin-based passive force. The amounts of fragmented titin were unchanged by the stimulation. Protein kinase Cα-treatment increased the passive force in stimulated fibers to resting levels. The stimulation had no effect on the maximum Ca2+-activated force (max Ca2+ force) at a sarcomere length (SL) of 2.4 μm and decreased myofibrillar (my)-Ca2+ sensitivity at 2.6-μm SL. Stretching the SL to 3.0 μm led to the augmentation of the max Ca2+ force and my-Ca2+ sensitivity in both rested and stimulated fibers. For the max Ca2+ force, the extent of the increase was smaller in stimulated than in rested fibers, whereas for my-Ca2+ sensitivity, it was higher in stimulated than in rested fibers. These results suggest that vigorous isometric contractions decrease the titin-based passive force, possibly because of a reduction in phosphorylation by protein kinase Cα, and that the decreased titin stiffness may contribute, at least in part, to muscle fatigue.
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Affiliation(s)
- Jiayu Shi
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashihiroshima-shi, Japan
| | - Daiki Watanabe
- Graduate School of Humanities and Social Sciences, Hiroshima University, Higashihiroshima-shi, Japan
| | - Masanobu Wada
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashihiroshima-shi, Japan
- Graduate School of Humanities and Social Sciences, Hiroshima University, Higashihiroshima-shi, Japan
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Kaya CS, Yılmaz EO, Akdeniz-Doğan ZD, Yucesoy CA. Long-Term Effects With Potential Clinical Importance of Botulinum Toxin Type-A on Mechanics of Muscles Exposed. Front Bioeng Biotechnol 2020; 8:738. [PMID: 32695774 PMCID: PMC7338794 DOI: 10.3389/fbioe.2020.00738] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 06/10/2020] [Indexed: 12/17/2022] Open
Abstract
Botulinum toxin type-A (BTX-A) is widely used for spasticity management and mechanically aims at reducing passive resistance at the joint and widening joint range of movement. However, recent experiments on acute BTX-A effects showed that the injected rat tibialis anterior (TA) muscle’s passive forces increased, and the length range of active force exertion (lrange) did not change. Additionally, BTX-A was shown to spread into non-injected muscles in the compartment and affect their mechanics. Whether those effects persist in the long term is highly important, but unknown. The aim was to test the following hypotheses with experiments conducted in the anterior crural compartment of the rat: In the long term, BTX-A (1) maintains lrange, (2) increases passive forces of the injected TA muscle, and (3) spreads into non-injected extensor digitorum longus (EDL) and the extensor hallucis longus (EHL) muscles, also affecting their active and passive forces. Male Wistar rats were divided into two groups: BTX-A and Control (0.1 units of BTX-A or only saline was injected into the TA). Isometric forces of the muscles were measured simultaneously 1-month post-injection. The targeted TA was lengthened, whereas the non-targeted EDL and EHL were kept at constant length. Hydroxyproline analysis was done to quantify changes in the collagen content of studied muscles. Two-way ANOVA test (for muscle forces, factors: TA length and animal group) and unpaired t or Mann-Whitney U test (for lrange and collagen content, where appropriate) were used for statistical analyses (P < 0.05). BTX-A caused significant effects. TA: active forces decreased (maximally by 75.2% at short and minimally by 48.3%, at long muscle lengths), lrange decreased (by 22.9%), passive forces increased (by 12.3%), and collagen content increased (approximately threefold). EDL and EHL: active forces decreased (up to 66.8%), passive force increased (minimally by 62.5%), and collagen content increased (approximately twofold). Therefore, hypothesis 1 was rejected and 2 and 3 were confirmed indicating that previously reported acute BTX-A effects persist and advance in the long term. A narrower lrange and an elevated passive resistance of the targeted muscle are unintended mechanical effects, whereas spread of BTX-A into other compartmental muscles indicates the presence of uncontrolled mechanical effects.
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Affiliation(s)
- Cemre S Kaya
- Institute of Biomedical Engineering, Boğaziçi University, Istanbul, Turkey
| | - Evrim O Yılmaz
- Institute of Biomedical Engineering, Boğaziçi University, Istanbul, Turkey
| | - Zeynep D Akdeniz-Doğan
- Department of Plastic Reconstructive and Aesthetic Surgery, Marmara University, Istanbul, Turkey
| | - Can A Yucesoy
- Institute of Biomedical Engineering, Boğaziçi University, Istanbul, Turkey
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von Twickel A, Guschlbauer C, Hooper SL, Büschges A. Swing Velocity Profiles of Small Limbs Can Arise from Transient Passive Torques of the Antagonist Muscle Alone. Curr Biol 2019; 29:1-12.e7. [PMID: 30581019 DOI: 10.1016/j.cub.2018.11.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/18/2018] [Accepted: 11/05/2018] [Indexed: 01/31/2023]
Abstract
In large limbs, changing motor neuron activity typically controls within-movement velocity. For example, sequential agonist-antagonist-agonist motor neuron firing typically underlies the slowing often present at the end of human reaches. In physiological movements of large limbs, antagonistic muscle passive torque is generally negligible. In small limbs, alternatively, passive torques can determine limb rest position, generate restoring movements to it, and decrease agonist-generated movement amplitude and velocity maxima. These observations suggest that, in small limbs, passive forces might also control velocity changes within movements. We investigated this issue in stick insect middle leg femur-tibia (FT) joint. During swing, the FT joint extensor muscle actively shortens and the flexor muscle passively lengthens. As in human reaching, after its initial acceleration, FT joint velocity continuously decreases. We measured flexor passive forces during imposed stretches spanning the ranges of FT joint angles, angular velocities, and movement amplitudes present in leg swings. The viscoelastic "transient" passive force that occurs during and soon after stretch depended on all three variables and could be tens of times larger than the "steady-state" passive force commonly measured long after stretch end. We combined these data, the flexor and extensor moment arms, and an existing extensor model to simulate FT joint swing. To measure only passive (flexor) muscle-dependent effects, we used constant extensor activations in these simulations. In simulations using data from ten flexor muscles, flexor passive torque could always produce swings with, after swing initiation, continuously decreasing velocities. Antagonist muscle passive torques alone can thus control within-movement velocity.
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Abstract
The length of a muscle's moment arm can be estimated noninvasively using ultrasound and the tendon excursion method. The main assumption with the tendon excursion method is that the force acting on the tendon during passive rotation is constant. However, passive force changes through the range of motion, and thus moment arm is underestimated. The authors attempted to account for passive force on the measurement of Achilles tendon moment arm using the tendon excursion method in 8 male and female runners. Tendon excursion was measured using ultrasound while the ankle was passively rotated at 0.17 rad·s-1. Moment arm was calculated at 5° intervals as the ratio of tendon displacement to joint rotation from 70° to 115°. Passive moment (MP) was measured using a dynamometer. The displacement attributable to MP was calculated by monitoring tendon displacement during a ramp isometric maximum contraction. MP was 5.7 (2.1) N·m at 70° and decreased exponentially from 70° to 90°. This resulted in MP-corrected moment arms that were significantly larger than uncorrected moment arms at joint angles where MP was present. Furthermore, MP-corrected moment arms did not change with ankle angle, which was not the case for uncorrected moment arms.
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Ait-Mou Y, Hsu K, Farman GP, Kumar M, Greaser ML, Irving TC, de Tombe PP. Titin strain contributes to the Frank-Starling law of the heart by structural rearrangements of both thin- and thick-filament proteins. Proc Natl Acad Sci U S A 2016; 113:2306-11. [PMID: 26858417 DOI: 10.1073/pnas.1516732113] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Frank-Starling mechanism of the heart is due, in part, to modulation of myofilament Ca(2+) sensitivity by sarcomere length (SL) [length-dependent activation (LDA)]. The molecular mechanism(s) that underlie LDA are unknown. Recent evidence has implicated the giant protein titin in this cellular process, possibly by positioning the myosin head closer to actin. To clarify the role of titin strain in LDA, we isolated myocardium from either WT or homozygous mutant (HM) rats that express a giant splice isoform of titin, and subjected the muscles to stretch from 2.0 to 2.4 μm of SL. Upon stretch, HM compared with WT muscles displayed reduced passive force, twitch force, and myofilament LDA. Time-resolved small-angle X-ray diffraction measurements of WT twitching muscles during diastole revealed stretch-induced increases in the intensity of myosin (M2 and M6) and troponin (Tn3) reflections, as well as a reduction in cross-bridge radial spacing. Independent fluorescent probe analyses in relaxed permeabilized myocytes corroborated these findings. X-ray electron density reconstruction revealed increased mass/ordering in both thick and thin filaments. The SL-dependent changes in structure observed in WT myocardium were absent in HM myocardium. Overall, our results reveal a correlation between titin strain and the Frank-Starling mechanism. The molecular basis underlying this phenomenon appears not to involve interfilament spacing or movement of myosin toward actin but, rather, sarcomere stretch-induced simultaneous structural rearrangements within both thin and thick filaments that correlate with titin strain and myofilament LDA.
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Leite FS, Minozzo FC, Kalganov A, Cornachione AS, Cheng YS, Leu NA, Han X, Saripalli C, Yates JR, Granzier H, Kashina AS, Rassier DE. Reduced passive force in skeletal muscles lacking protein arginylation. Am J Physiol Cell Physiol 2015; 310:C127-35. [PMID: 26511365 DOI: 10.1152/ajpcell.00269.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 10/28/2015] [Indexed: 11/22/2022]
Abstract
Arginylation is a posttranslational modification that plays a global role in mammals. Mice lacking the enzyme arginyltransferase in skeletal muscles exhibit reduced contractile forces that have been linked to a reduction in myosin cross-bridge formation. The role of arginylation in passive skeletal myofibril forces has never been investigated. In this study, we used single sarcomere and myofibril measurements and observed that lack of arginylation leads to a pronounced reduction in passive forces in skeletal muscles. Mass spectrometry indicated that skeletal muscle titin, the protein primarily linked to passive force generation, is arginylated on five sites located within the A band, an important area for protein-protein interactions. We propose a mechanism for passive force regulation by arginylation through modulation of protein-protein binding between the titin molecule and the thick filament. Key points are as follows: 1) active and passive forces were decreased in myofibrils and single sarcomeres isolated from muscles lacking arginyl-tRNA-protein transferase (ATE1). 2) Mass spectrometry revealed five sites for arginylation within titin molecules. All sites are located within the A-band portion of titin, an important region for protein-protein interactions. 3) Our data suggest that arginylation of titin is required for proper passive force development in skeletal muscles.
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Affiliation(s)
- Felipe S Leite
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Fábio C Minozzo
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Albert Kalganov
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Anabelle S Cornachione
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Yu-Shu Cheng
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Nicolae A Leu
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Xuemei Han
- The Scripps Research Institute, Department of Chemical Physiology, La Jolla, California
| | - Chandra Saripalli
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona; and
| | - John R Yates
- The Scripps Research Institute, Department of Chemical Physiology, La Jolla, California
| | - Henk Granzier
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona; and
| | - Anna S Kashina
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Dilson E Rassier
- Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada; Departments of Physics and Physiology, McGill University, Montreal, Quebec, Canada
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Abstract
The dystrophin-associated glycoprotein complex (DGC) and the α7β1-integrin complex are two independent protein complexes that link the extracellular matrix with the cytoskeleton in muscle cells. These associations stabilize the sarcolemma during force transmission. Loss of either one of these complexes leads to muscular dystrophy. Dystrophin is a major component of the DGC. Its absence results in Duchenne muscular dystrophy (DMD). Because α7-integrin overexpression has been shown to ameliorate muscle histopathology in mouse models of DMD, we hypothesize that the α7β1-integrin complex can help preserve muscle function. To test this hypothesis, we evaluated muscle force, elasticity, and the viscous property of the extensor digitorum longus muscle in 19-day-old normal BL6, dystrophin-null mdx4cv, α7-integrin-null, and dystrophin/α7-integrin double knockout mice. While nominal changes were found in single knockout mice, contractility and passive properties were significantly compromised in α7-integrin double knockout mice. Our results suggest that DGC and α7β1-integrin complexes may compensate each other to maintain normal skeletal muscle function. α7β1-Integrin upregulation may hold promise to treat not only histological, but also physiological, defects in DMD.
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Affiliation(s)
- Chady H Hakim
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri
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