Journal articles: 'Human skeletal muscle'

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Sandage, Mary J., and Audrey G. Smith. "Muscle Bioenergetic Considerations for Intrinsic Laryngeal Skeletal Muscle Physiology." Journal of Speech, Language, and Hearing Research 60, no. 5 (May 24, 2017): 1254–63. http://dx.doi.org/10.1044/2016_jslhr-s-16-0192.

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PurposeIntrinsic laryngeal skeletal muscle bioenergetics, the means by which muscles produce fuel for muscle metabolism, is an understudied aspect of laryngeal physiology with direct implications for voice habilitation and rehabilitation. The purpose of this review is to describe bioenergetic pathways identified in limb skeletal muscle and introduce bioenergetic physiology as a necessary parameter for theoretical models of laryngeal skeletal muscle function.MethodA comprehensive review of the human intrinsic laryngeal skeletal muscle physiology literature was conducted. Findings regarding intrinsic laryngeal muscle fiber complement and muscle metabolism in human models are summarized and exercise physiology methodology is applied to identify probable bioenergetic pathways used for voice function.ResultsIntrinsic laryngeal skeletal muscle fibers described in human models support the fast, high-intensity physiological requirements of these muscles for biological functions of airway protection. Inclusion of muscle bioenergetic constructs in theoretical modeling of voice training, detraining, fatigue, and voice loading have been limited.ConclusionsMuscle bioenergetics, a key component for muscle training, detraining, and fatigue models in exercise science, is a little-considered aspect of intrinsic laryngeal skeletal muscle physiology. Partnered with knowledge of occupation-specific voice requirements, application of bioenergetics may inform novel considerations for voice habilitation and rehabilitation.

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Ahmed, A., D. L. Maxwell, P. M. Taylor, and M. J. Rennie. "Glutamine transport in human skeletal muscle." American Journal of Physiology-Endocrinology and Metabolism 264, no. 6 (June 1, 1993): E993—E1000. http://dx.doi.org/10.1152/ajpendo.1993.264.6.e993.

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Sarcolemmal vesicles isolated from human skeletal muscle obtained at surgery showed approximately 14-fold enrichment of sarcolemmal marker enzymes 5'-nucleotidase and K-stimulated phosphatase. [3H]glutamine transport in these vesicles was stereospecific, largely Na dependent, and tolerated Li-for-Na substitution. Glutamine transport was stimulated by an inside negative membrane potential, and 25 mM glutamine stimulated 22Na (0.1 mM) uptake into vesicles by 50%, indicating rheogenic cotransport of Na and glutamine. Alanine transport was Na dependent but did not tolerate Li-for-Na substitution. Transport of L-[3H]glutamine was inhibited by 35-65% with a 20-fold excess of glutamine, asparagine, and alanine; cysteine, alpha-(methylamino)isobutyrate, and 2-amino-2-norborane carboxylic acid had smaller inhibitory effects, although cysteine had an unusually large inhibitory effect on glutamine transport at 1,000-fold excess compared with most other amino acids. Glutamine transport showed sensitivity to pH values < 7.0. Glutamine transport consisted of a Na-dependent and a Na-independent component, both of which appeared saturable. The kinetic characteristics of the Na-dependent component were different in different types of muscles, with half-maximal concentrations (mM) varying from 1.6 +/- 0.4 (tibialis anterior) to 0.56 +/- 0.0.2 (gluteus maximus) and maximal velocity (pmol.mg protein-1.s-1) of 1.3 +/- 0.27 to 5 +/- 1.25 in the same muscles. The results demonstrate both marked similarities and important differences between the principal glutamine transporter in human skeletal muscle and the known system Nm transporter in rat skeletal muscle.

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Norheim, Frode, Truls Raastad, Bernd Thiede, Arild C. Rustan, Christian A. Drevon, and Fred Haugen. "Proteomic identification of secreted proteins from human skeletal muscle cells and expression in response to strength training." American Journal of Physiology-Endocrinology and Metabolism 301, no. 5 (November 2011): E1013—E1021. http://dx.doi.org/10.1152/ajpendo.00326.2011.

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Regular physical activity protects against several types of diseases. This may involve altered secretion of signaling proteins from skeletal muscle. Our aim was to identify the most abundantly secreted proteins in cultures of human skeletal muscle cells and to monitor their expression in muscles of strength-training individuals. A total of 236 proteins were detected by proteome analysis in medium conditioned by cultured human myotubes, which was narrowed down to identification of 18 classically secreted proteins expressed in skeletal muscle, using the SignalP 3.0 and Human Genome Expression Profile databases together with a published mRNA-based reconstruction of the human skeletal muscle secretome. For 17 of the secreted proteins, expression was confirmed at the mRNA level in cultured human myotubes as well as in biopsies of human skeletal muscles. RT-PCR analyses showed that 15 of the secreted muscle proteins had significantly enhanced mRNA expression in m. vastus lateralis and/or m. trapezius after 11 wk of strength training among healthy volunteers. For example, secreted protein acidic and rich in cysteine, a secretory protein in the membrane fraction of skeletal muscle fibers, was increased 3- and 10-fold in m. vastus lateralis and m. trapezius, respectively. Identification of proteins secreted by skeletal muscle cells in vitro facilitated the discovery of novel responses in skeletal muscles of strength-training individuals.

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Maganaris, Constantinos N., Vasilios Baltzopoulos, D. Ball, and Anthony J. Sargeant. "In vivo specific tension of human skeletal muscle." Journal of Applied Physiology 90, no. 3 (March 1, 2001): 865–72. http://dx.doi.org/10.1152/jappl.2001.90.3.865.

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In this study, we estimated the specific tensions of soleus (Sol) and tibialis anterior (TA) muscles in six men. Joint moments were measured during maximum voluntary contraction (MVC) and during electrical stimulation. Moment arm lengths and muscle volumes were measured using magnetic resonance imaging, and pennation angles and fascicular lengths were measured using ultrasonography. Tendon and muscle forces were modeled. Two approaches were followed to estimate specific tension. First, muscle moments during electrical stimulation and moment arm lengths, fascicular lengths, and pennation angles during MVC were used ( data set A). Then, MVC moments, moment arm lengths at rest, and cadaveric fascicular lengths and pennation angles were used ( data set B). The use of data set B yielded the unrealistic specific tension estimates of 104 kN/m2 in Sol and 658 kN/m2 in TA. The use of data set A, however, yielded values of 150 and 155 kN/m2 in Sol and TA, respectively, which agree with in vitro results from fiber type I-predominant muscles. In fact, both Sol and TA are such muscles. Our study demonstrates the feasibility of accurate in vivo estimates of human muscle intrinsic strength.

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Hansen, J., G. D. Thomas, T. N. Jacobsen, and R. G. Victor. "Muscle metaboreflex triggers parallel sympathetic activation in exercising and resting human skeletal muscle." American Journal of Physiology-Heart and Circulatory Physiology 266, no. 6 (June 1, 1994): H2508—H2514. http://dx.doi.org/10.1152/ajpheart.1994.266.6.h2508.

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Activation of a metabolically generated reflex in exercising skeletal muscle (muscle metaboreflex) in humans is known to trigger increases in sympathetic nerve activity (SNA) to resting skeletal muscles. In seven healthy human subjects, to determine whether this reflex mechanism also increases SNA to the exercising muscles, we recorded muscle SNA with microelectrodes in the right peroneal nerve and in fascicles of the left peroneal nerve selectively innervating the exercising muscles of the left foot. Subjects performed static toe extension at 20% maximal voluntary contraction alone or in combination with foot ischemia. Only static toe extension at 20% MVC during ischemia activated the muscle metaboreflex. This paradigm caused increases in SNA to exercising muscle that paralleled those to the resting muscles: during the first minute of exercise SNA was unchanged, but during the second minute SNA increased from 29 +/- 2 to 38 +/- 2 bursts/min (P < 0.05) to the exercising muscles and from 30 +/- 3 to 40 +/- 2 bursts/min (P < 0.05) to the resting muscles. These bilateral increases in SNA were maintained when metaboreflex activation was sustained by postexercise foot ischemia. In conclusion, these data provide neurophysiological evidence that the muscle metaboreflex evokes parallel sympathetic activation in exercising and resting human skeletal muscle.

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Tirrell, T. F., M. S. Cook, J. A. Carr, E. Lin, S. R. Ward, and R. L. Lieber. "Human skeletal muscle biochemical diversity." Journal of Experimental Biology 215, no. 15 (July 11, 2012): 2551–59. http://dx.doi.org/10.1242/jeb.069385.

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Tirrell, T. F., M. S. Cook, J. A. Carr, E. Lin, S. R. Ward, and R. L. Lieber. "Human skeletal muscle biochemical diversity." Journal of Experimental Biology 215, no. 16 (July 25, 2012): 2931. http://dx.doi.org/10.1242/jeb.077347.

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Vicart, S., D. Sternberg, B. Fontaine, and G. Meola. "Human skeletal muscle sodium channelopathies." Neurological Sciences 26, no. 4 (October 2005): 194–202. http://dx.doi.org/10.1007/s10072-005-0461-x.

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Rasmussen, U. F., and H. N. Rasmussen. "Human skeletal muscle mitochondrial capacity." Acta Physiologica Scandinavica 168, no. 4 (April 2000): 473–80. http://dx.doi.org/10.1046/j.1365-201x.2000.00699.x.

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Zhang, Tan, Xin Feng, Bo Feng, Juan Dong, Karen Haas, Barbara M. Nicklas, Osvaldo Delbono, and Stephen Kritchevsky. "CARDIAC TROPONIN T MEDIATED AUTOIMMUNE RESPONSE AND ITS ROLE IN SKELETAL MUSCLE AGING." Innovation in Aging 3, Supplement_1 (November 2019): S882. http://dx.doi.org/10.1093/geroni/igz038.3231.

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Abstract Cardiac troponin T (cTnT), a key component of contractile machinery essential for muscle contraction, is also expressed in skeletal muscle under certain conditions (e.g. neuromuscular diseases and aging). We have reported that skeletal muscle cTnT regulates neuromuscular junction denervation preferentially in fast skeletal muscle of old mice. Here, we further report that cTnT is also enriched within some myofibers, and/or along microvascular walls in old mice fast skeletal muscle. Strikingly, immunoglobulin G (IgG), together with markers of complement system activation, cell death (necroptosis or apoptosis), and macrophage infiltration, were all found to be co-localized with cTnT and IgG in those areas. In addition, elevated cTnT and IgG are associated with lower dystrophin expression on muscle fiber membrane, lower muscle capillary density, and reduced muscle performance (wire hanging test). Using purified recombinant TnT proteins, we confirmed that only cTnT, but not slow or fast skeletal muscle TnT1 or TnT3, was detected by immunoblot using sera from old (but not young) mice with pre-determined elevated cTnT and IgG in their skeletal muscle, indicating the existence of anti-cTnT autoantibodies in sera (previously found in human blood) and skeletal muscle of old mice. Immunoblotting further revealed that the age related changes in skeletaI muscle cTnT and IgG are more prominent in fast skeletal muscle than in slow. Importantly, elevated cTnT and IgG were also detected in skeletal muscles from 4 older adults (65-70 yrs, IMFIT). Our finding suggests a novel autoimmune mechanism mediated by cTnT that underlies age related skeletal muscle abnormalities and dysfunction.

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Ricchiuti, Vincent, and Fred S. Apple. "RNA Expression of Cardiac Troponin T Isoforms in Diseased Human Skeletal Muscle." Clinical Chemistry 45, no. 12 (December 1, 1999): 2129–35. http://dx.doi.org/10.1093/clinchem/45.12.2129.

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Abstract Background: The expression of multiple cardiac troponin T (cTnT) isoforms has been demonstrated in diseased human skeletal muscle. However, cardiac troponin I (cTnI) expression has been described only in heart muscle. The goal of this study was to determine whether mRNA for cTnT, slow skeletal troponin T (sTnT), or cTnI was expressed in skeletal muscle biopsies obtained from patients with end-stage renal disease (ESRD) and Duchenne muscular dystrophy (DMD). Methods: Total mRNA was extracted from healthy human heart (n = 4), healthy human skeletal muscle (n = 5), and skeletal muscle from patients with ESRD (n = 7) and DMD (n = 5). Total RNA (1 μg) was reverse-transcribed using Moloney murine leukemia virus reverse transcriptase. The reverse-transcribed cDNAs were amplified by PCR using oligonucleotide primers specific for cTnT, sTnT, and cTnI sequences (GenBank accession numbers X74819, m19308, and X54163, respectively). Results: In all heart specimens, a 150-bp cTnT amplicon was detected. Skeletal muscle from four of seven patients with ESRD and two of five patients with DMD showed expression of a 150-bp amplicon. Using DNA sequencing and a comparison program, the 150-bp amplicons found in heart and diseased skeletal muscle specimens were 100% identical and specific to the cTnT mRNA sequence. No cTnT mRNA expression was found in healthy skeletal muscle. No evidence of sTnT mRNA was found in heart muscle. A 200-bp sTnT amplicon specific to a human sTnT sequence was detected in all skeletal muscle specimens. A 250-bp cTnI amplicon specific to the cTnI sequence was detected in all heart specimens. However, no cTnI mRNA expression was found in healthy or diseased skeletal muscle specimens. cTnT mRNA expression in both heart and diseased skeletal muscles corresponded with cTnT isoform expression, respectively, as determined by Western blot analysis. Conclusion: Our findings demonstrate cTnT mRNA expression, but no cTnI mRNA expression, by reverse transcription-PCR in diseased human skeletal muscle that expresses cTnT isoforms.

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Miyanishi, Shouji, and Tadashi Kashima. "Trajectory Formation in Human Arm Movements Based on Joint Motor Model Demonstrating Muscle Characteristics(Musculo-Skeletal Mechanics)." Proceedings of the Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics 2004.1 (2004): 149–50. http://dx.doi.org/10.1299/jsmeapbio.2004.1.149.

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Akhtaruzzaman, M., A. A. Shafie, and M. R. Khan. "A REVIEW ON LOWER APPENDICULAR MUSCULOSKELETAL SYSTEM OF HUMAN BODY." IIUM Engineering Journal 17, no. 1 (April 30, 2016): 83–102. http://dx.doi.org/10.31436/iiumej.v17i1.571.

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Rehabilitation engineering plays an important role in designing various autonomous robots to provide better therapeutic exercise to disabled patients. Hence it is necessary to study human musculoskeletal system and also needs to be presented in scientific manner in order to describe and analyze the biomechanics of human body motion. This review focuses on lower appendicular musculoskeletal structure of human body to represent joints and links architectures; to identify muscle attachments and functions; and to illustrate muscle groups which are responsible for a particular joint movement. Firstly, human lower skeletal structure, linking systems, joint mechanisms, and their functions are described with a conceptual representation of joint architecture of human skeleton. This section also represents joints and limbs by comparing with mechanical systems. Characteristics of ligaments and their functions to construct skeletal joints are also discussed briefly in this part. Secondly, the study focuses on muscular system of human lower limbs where muscle structure, functions, roles in moving endoskeleton structure, and supporting mechanisms are presented elaborately. Thirdly, muscle groups are tabulated based on functions that provide mobility to different joints of lower limbs. Finally, for a particular movement action of lower extremity, muscles are also grouped and tabulated to have a better understanding on functions of individual muscle. Basically the study presents an overview of the structure of human lower limbs by characterizing and classifying skeletal and muscular systems.KEYWORDS: Â Musculoskeletal system; Human lower limbs; Muscle groups; Joint motion; Biomechatronics; Rehabilitation.

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Wada, M., T. Okumoto, K. Toro, K. Masuda, T. Fukubayashi, K. Kikuchi, S. Niihata, and S. Katsuta. "Expression of hybrid isomyosins in human skeletal muscle." American Journal of Physiology-Cell Physiology 271, no. 4 (October 1, 1996): C1250—C1255. http://dx.doi.org/10.1152/ajpcell.1996.271.4.c1250.

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Myosin of human skeletal muscles was analyzed by means of several electrophoretic techniques. Myosin heavy chain (HC)-IIa-and HC-IIb-based isomyosins were identified by pyrophosphate-polyacrylamide gel electrophoresis (PP-PAGE). The electrophoretic mobilities of these fast-twitch muscle isomyosins differed in the order HC-IIa triplets < HC-IIb triplets. To determine the subunit composition of myosin molecules that function in intact muscle, two-dimensional electrophoresis in which the first and second dimensions were PP-PAGE and sodium dodecyl sulfate-PAGE, respectively, was also performed. Slow-twitch muscle isomyosin contained, in addition to slow-twitch light chain (LC) and HC-I isoforms, appreciable amounts of LC-2f, HC-IIa, and HC-IIb isoforms, and fast-twitch muscle isomyosin consisted of LC-2s and HC-I isoforms as well as fast-twitch LC and HC isoforms. Without consideration of HC- and slow-twitch alkali LC heterodimers, at least 31 possible isomyosins are derived from these findings on the subunit composition of isomyosins in human skeletal muscle.

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Bickel, C. Scott, Jill M. Slade, Gordon L. Warren, and Gary A. Dudley. "Fatigability and Variable-Frequency Train Stimulation of Human Skeletal Muscles." Physical Therapy 83, no. 4 (April 1, 2003): 366–73. http://dx.doi.org/10.1093/ptj/83.4.366.

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Abstract Background and Purpose. The quadriceps femoris (QF) and tibialis anterior (TA) muscles are often activated through the use of electrical stimulation by physical therapists. These 2 muscles are fundamentally different in regard to their fiber-type composition. Whether protocols developed using a given muscle can be applied to another muscle has seldom been questioned, even if they differ in fiber type. The purpose of this study was to test the hypothesis that torque augmentation during variable-frequency train (VFT) stimulation as compared with constant-frequency train (CFT) stimulation in the fatigued state would not differ between these muscles, even though the TA muscle has 50% relatively more slow fibers than the QF muscle relative to each muscle's overall composition. Subjects. Ten recreationally active men with no history of lower-extremity pathology participated in the study (mean age=25 years, SD=4, range=19–31; mean height=179 cm, SD=5, range=170–188; mean body mass=80 kg, SD=15, range=63–111). Methods. The subjects' TA and QF muscles were stimulated with CFTs (six 200-microsecond square waves separated by 70 milliseconds) or VFTs (first interpulse interval=5 milliseconds) that evoked an isometric contraction. Results. After potentiation, the torque-time integral and peak torque were not different for the VFT and CFT stimulation. Rise time was longer for the TA muscle than for the QF muscle and for CFT stimulation versus VFT stimulation (both approximately 40%). After 180 CFTs (50% duty cycle), peak torque decreased 56% overall, with no differences between muscles. Enhancement of the torque-time integral (25%) by VFT stimulation was not different between fatigued QF and TA muscles. Torque augmentation was due to the VFT stimulation evoking 27% greater peak torque and less slowing of rise time than the CFT stimulation (15% versus 30%). Discussion and Conclusion. The results indicate that the QF muscle may not necessarily fatigue more than the TA muscle. The results suggest that VFTs augment the force of fatigued, human skeletal muscle irrespective of fiber type.

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Powell, Courtney A., Beth L. Smiley, John Mills, and Herman H. Vandenburgh. "Mechanical stimulation improves tissue-engineered human skeletal muscle." American Journal of Physiology-Cell Physiology 283, no. 5 (November 1, 2002): C1557—C1565. http://dx.doi.org/10.1152/ajpcell.00595.2001.

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Human bioartificial muscles (HBAMs) are tissue engineered by suspending muscle cells in collagen/MATRIGEL, casting in a silicone mold containing end attachment sites, and allowing the cells to differentiate for 8 to 16 days. The resulting HBAMs are representative of skeletal muscle in that they contain parallel arrays of postmitotic myofibers; however, they differ in many other morphological characteristics. To engineer improved HBAMs, i.e., more in vivo-like, we developed Mechanical Cell Stimulator (MCS) hardware to apply in vivo-like forces directly to the engineered tissue. A sensitive force transducer attached to the HBAM measured real-time, internally generated, as well as externally applied, forces. The muscle cells generated increasing internal forces during formation which were inhibitable with a cytoskeleton depolymerizer. Repetitive stretch/relaxation for 8 days increased the HBAM elasticity two- to threefold, mean myofiber diameter 12%, and myofiber area percent 40%. This system allows engineering of improved skeletal muscle analogs as well as a nondestructive method to determine passive force and viscoelastic properties of the resulting tissue.

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Eržen, Ida. "PLASTICITY OF SKELETAL MUSCLE STUDIED BY STEREOLOGY." Image Analysis & Stereology 23, no. 3 (May 3, 2011): 143. http://dx.doi.org/10.5566/ias.v23.p143-152.

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The present contribution provides an overview of stereological methods applied in the skeletal muscle research at the Institute of Anatomy of the Medical Faculty in Ljubljana. Interested in skeletal muscle plasticity we studied three different topics: (i) expression of myosin heavy chain isoforms in slow and fast muscles under experimental conditions, (ii) frequency of satellite cells in young and old human and rat muscles and (iii) capillary supply of rat fast and slow muscles. We analysed the expression of myosin heavy chain isoforms within slow rat soleus and fast extensor digitorum longus muscles after (i) homotopic and heterotopic transplantation of both muscles, (ii) low frequency electrical stimulation of the fast muscle and (iii) transposition of the fast nerve to the slow muscle. The models applied were able to turn the fast muscle into a completely slow muscle, but not vice versa. One of the indicators for the regenerative potential of skeletal muscles is its satellite cell pool. The estimated parameters, number of satellite cells per unit fibre length, corrected to the reference sarcomere length (Nsc/Lfib) and number of satellite cells per number of nuclei (myonuclei and satellite cell nuclei) (Nsc/Nnucl) indicated that the frequency of M-cadherin stained satellite cells declines in healthy old human and rat muscles compared to young muscles. To access differences in capillary densities among slow and fast muscles and slow and fast muscle fibres, we have introduced Slicer and Fakir methods, and tested them on predominantly slow and fast rat muscles. Discussing three different topics that require different approach, the present paper reflects the three decades of the development of stereological methods: 2D analysis by simple point counting in the 70's, the disector in the 80's and virtual spatial probes in the 90's. In all methods the interactive computer assisted approach was utilised.

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Staron, Robert S. "Human Skeletal Muscle Fiber Types: Delineation, Development, and Distribution." Canadian Journal of Applied Physiology 22, no. 4 (August 1, 1997): 307–27. http://dx.doi.org/10.1139/h97-020.

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This brief review attempts to summarize a number of studies on the delineation, development, and distribution of human skeletal muscle fiber types. A total of seven fiber types can be identified in human limb and trunk musculature based on the pH stability/ability of myofibrillar adenosine triphosphatase (mATPase). For most human muscles, mATPase-based fiber types correlate with the myosin heavy chain (MHC) content. Thus, each histochemically identified fiber has a specific MHC profile. Although this categorization is useful, it must be realized that muscle fibers are highly adaptable and that innumerable fiber type transients exist. Also, some muscles contain specific MHC isoforms and/or combinations that do not permit routine mATPase-based fiber typing. Although the major populations of fast and slow are, for the most part, established shortly after birth, subtle alterations take place throughout life. These changes appear to relate to alterations in activity and/or hormonal levels, and perhaps later in life, total fiber number. Because large variations in fiber type distribution can be found within a muscle and between individuals, interpretation of data gathered from human muscle is often difficult. Key words: aging, myosin heavy chains, myogenesis, myofibrillar adenosine triphosphate

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Vandenborne, K., G. Walter, L. Ploutz-Snyder, R. Staron, A. Fry, K. De Meirleir, G. A. Dudley, and J. S. Leigh. "Energy-rich phosphates in slow and fast human skeletal muscle." American Journal of Physiology-Cell Physiology 268, no. 4 (April 1, 1995): C869—C876. http://dx.doi.org/10.1152/ajpcell.1995.268.4.c869.

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We investigated the relationship between energy-rich phosphate content and muscle fiber-type composition in human skeletal muscle using a combination of 31P-nuclear magnetic resonance spectroscopy (NMR), histochemical, and biochemical analyses of muscle biopsies. Localized 31P spectra were collected simultaneously from the predominantly slow-twitch soleus muscle and the mixed (fast-twitch and slow-twitch) medial and lateral gastrocnemius muscles, using B1-insensitive Hadamard Spectroscopic Imaging. Biopsy samples were taken from the soleus and lateral gastrocnemius muscles before NMR investigation and analyzed for fiber type composition and succinic dehydrogenase (SDH) activity. Fiber-type composition was determined based both on myofibrillar actomyosin ATPase activity combined with cross-sectional area and on myosin heavy-chain composition. Localized spectroscopy demonstrated a significantly (P < 0.001) higher P(i)/phosphocreatine ratio in the soleus muscle (0.15 +/- 0.01) compared with the medial (0.12 +/- 0.01) and lateral (0.10 +/- 0.0) gastrocnemius. However, in vitro analysis of muscle biopsies showed only a moderate relationship between the basal phosphate content and myofibrillar actomyosin ATPase-based fiber-type composition and SDH activity, respectively.

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Gustafsson, Thomas. "Vascular remodelling in human skeletal muscle." Biochemical Society Transactions 39, no. 6 (November 21, 2011): 1628–32. http://dx.doi.org/10.1042/bst20110720.

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Exercise-induced angiogenesis in skeletal muscle involves both non-sprouting and sprouting angiogenesis and results from the integrated responses of multiple systems and stimuli. VEGF-A (vascular endothelial growth factor A) levels are increased in exercised muscle and have been demonstrated to be critical for exercise-induced capillary growth. Only limited information is available regarding the role of other angiogenic and angiostatic factors in exercise, but changes in the angiopoietin family following repetitive bouts of exercise occur in a pattern that is favourable for angiogenesis. Results from other angiogenic model systems, indicate that miRNAs (microRNAs) are important factors in the regulation of angiogenesis and thus to explore their role as regulators of exercise induced angiogenesis will be an important avenue of study in the future. ECM (extracellular matrix) remodelling and activation of MMPs (matrix metalloproteinases) are, to some extent, overlooked players in skeletal muscle adaptation. Degradation of ECM proteins liberates angiogenic factors from immobilized matrix stores and make cell migration possible. In fact, it is known that MMPs become activated by a single bout of exercise in humans, rapid interstitial changes occur long before any changes in gene transcription could result in protein synthesis and inhibition of MMP activity completely abolishes sprouting angiogenesis. A growing body of evidence suggests that circulating and resident progenitor cells, in addition to other cell types located in skeletal muscle tissue, participate in skeletal muscle angiogenesis by various mechanisms. However, more studies are needed before these can be confirmed as mechanisms of exercise-induced capillary growth.

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Christoff, Nicholas. "The Development of Human Skeletal Muscle." Developmental Medicine & Child Neurology 7, no. 6 (November 12, 2008): 710–11. http://dx.doi.org/10.1111/j.1469-8749.1965.tb07855.x.

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Fenichel, Gerald M. "The Development of Human Skeletal Muscle." Developmental Medicine & Child Neurology 7, no. 1 (November 12, 2008): 69–72. http://dx.doi.org/10.1111/j.1469-8749.1965.tb10887.x.

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Guerra, Borja, Alfredo Santana, Teresa Fuentes, Safira Delgado-Guerra, Alfredo Cabrera-Socorro, Cecilia Dorado, and Jose A. L. Calbet. "Leptin receptors in human skeletal muscle." Journal of Applied Physiology 102, no. 5 (May 2007): 1786–92. http://dx.doi.org/10.1152/japplphysiol.01313.2006.

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Human skeletal muscle expresses leptin receptor mRNA; however, it remains unknown whether leptin receptors (OB-R) are also expressed at the protein level. Fourteen healthy men (age = 33.1 ± 2.0 yr, height = 175.9 ± 1.7 cm, body mass = 81.2 ± 3.8 kg, body fat = 22.5 ± 1.9%; means ± SE) participated in this investigation. The expression of OB-R protein was determined in skeletal muscle, subcutaneous adipose tissue, and hypothalamus using a polyclonal rabbit anti-human leptin receptor. Three bands with a molecular mass close to 170, 128, and 98 kDa were identified by Western blot with the anti-OB-R antibody. All three bands were identified in skeletal muscle: the 98-kDa and 170-kDa bands were detected in hypothalamus, and the 98-kDa and 128-kDa bands were detected in thigh subcutaneous adipose tissue. The 128-kDa isoform was not detected in four subjects, whereas in the rest its occurrence was fully explained by the presence of intermuscular adipose tissue, as demonstrated using an anti-perilipin A antibody. No relationship was observed between the basal concentration of leptin in serum and the 170-kDa band density. In conclusion, a long isoform of the leptin receptor with a molecular mass close to 170 kDa is expressed at the protein level in human skeletal muscle. The amount of 170-kDa protein appears to be independent of the basal concentration of leptin in serum.

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Ryan, Eric D., Trent J. Herda, Pablo B. Costa, Ashley A. Walter, Katie M. Hoge, Travis W. Beck, Jeffery R. Stout, and Joel T. Cramer. "Viscoelastic Creep In Human Skeletal Muscle." Medicine & Science in Sports & Exercise 41 (May 2009): 205. http://dx.doi.org/10.1249/01.mss.0000355182.58487.d2.

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Wolf, R., H. H. Goebel, L. Gutmann, and S. Schochet. "Capillaries within Human Skeletal Muscle Fibers." Pathology - Research and Practice 187, no. 7 (September 1991): 857–63. http://dx.doi.org/10.1016/s0344-0338(11)80583-2.

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Serdaroglu, P., H. Tasli, H. Hanagasi, and M. Emre. "Parkin expression in human skeletal muscle." Journal of Clinical Neuroscience 12, no. 8 (November 2005): 927–29. http://dx.doi.org/10.1016/j.jocn.2005.04.005.

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Carpenter, Stirling, and George Karpati. "Lysosomal storage in human skeletal muscle." Human Pathology 17, no. 7 (July 1986): 683–703. http://dx.doi.org/10.1016/s0046-8177(86)80179-4.

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Suzuki, Hidenori, Asako Hase, Yuhei Miyata, Kiichi Arahata, and C. Akazawa. "GDNF expression in human skeletal muscle." Neuroscience Research 31 (January 1998): S309. http://dx.doi.org/10.1016/s0168-0102(98)82422-x.

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Eckert, Peter, and Klaus Schnackerz. "Ischemic Tolerance of Human Skeletal Muscle." Annals of Plastic Surgery 26, no. 1 (January 1991): 77–84. http://dx.doi.org/10.1097/00000637-199101000-00012.

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Scott, Wayne, Jennifer Stevens, and Stuart A. Binder–Macleod. "Human Skeletal Muscle Fiber Type Classifications." Physical Therapy 81, no. 11 (November 1, 2001): 1810–16. http://dx.doi.org/10.1093/ptj/81.11.1810.

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31

URSO, MARIA L. "Disuse Atrophy of Human Skeletal Muscle." Medicine & Science in Sports & Exercise 41, no. 10 (October 2009): 1860–68. http://dx.doi.org/10.1249/mss.0b013e3181a6458a.

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32

Giometti, Carol S., and Moris J. Danon. "Heterogeneity of human skeletal muscle tropomyosin." Annals of Neurology 18, no. 2 (August 1985): 234–43. http://dx.doi.org/10.1002/ana.410180211.

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Tirrell, Timothy F., Mark Cook, John A. Carr, Anthony J. Choi, Evie Lin, Mary C. Esparza, Samuel R. Ward, and Richard L. Lieber. "Biochemical Diversity of Human Skeletal Muscle." Biophysical Journal 102, no. 3 (January 2012): 144a. http://dx.doi.org/10.1016/j.bpj.2011.11.791.

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Pallavicini, Alberto, Snezana Kojić, Camilla Bean, Mariz Vainzof, Michela Salamon, Chiara Ievolella, Gladis Bortoletto, et al. "Characterization of Human Skeletal Muscle Ankrd2." Biochemical and Biophysical Research Communications 285, no. 2 (July 2001): 378–86. http://dx.doi.org/10.1006/bbrc.2001.5131.

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Semmler, John G., Devin V. Kutzscher, and Roger M. Enoka. "Gender Differences in the Fatigability of Human Skeletal Muscle." Journal of Neurophysiology 82, no. 6 (December 1, 1999): 3590–93. http://dx.doi.org/10.1152/jn.1999.82.6.3590.

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After participating in a 4-wk intervention that reduced normal usage of the elbow flexor muscles, all six women, but only one of six men, experienced a marked increase in the endurance time during a low-force fatiguing contraction. The increase in endurance time was associated with an altered pattern of muscle activation that did not involve the commonly observed progressive increase in muscle activity. Rather, the muscle activity comprised intermittent motor unit activity. In those individuals who exhibited this behavior, the novel pattern of muscle activity was only present immediately after 4 wk of limb immobilization and not before the intervention or after 4 wk of recovery. These findings suggest possible differences between women and men in the adaptations of the neuromuscular system.

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Liu, Sophia Z., Bozena Jemiolo, Kaleen M. Lavin, Bridget E. Lester, Scott W. Trappe, and Todd A. Trappe. "Prostaglandin E2/cyclooxygenase pathway in human skeletal muscle: influence of muscle fiber type and age." Journal of Applied Physiology 120, no. 5 (March 1, 2016): 546–51. http://dx.doi.org/10.1152/japplphysiol.00396.2015.

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Prostaglandin E2 (PGE2) produced by the cyclooxygenase (COX) pathway regulates skeletal muscle protein turnover and exercise training adaptations. The purpose of this study was twofold: 1) define the PGE2/COX pathway enzymes and receptors in human skeletal muscle, with a focus on type I and II muscle fibers; and 2) examine the influence of aging on this pathway. Muscle biopsies were obtained from the soleus (primarily type I fibers) and vastus lateralis (proportionally more type II fibers than soleus) of young men and women ( n = 8; 26 ± 2 yr), and from the vastus lateralis of young ( n = 8; 25 ± 1 yr) and old ( n = 12; 79 ± 2 yr) men and women. PGE2/COX pathway proteins [COX enzymes (COX-1 and COX-2), PGE2 synthases (cPGES, mPGES-1, and mPGES-2), and PGE2 receptors (EP1, EP2, EP3, and EP4)] were quantified via Western blot. COX-1, cPGES, mPGES-2, and all four PGE2 receptors were detected in all skeletal muscle samples examined. COX-1 ( P < 0.1) and mPGES-2 were ∼20% higher, while EP3 was 99% higher and EP4 57% lower in soleus compared with vastus lateralis ( P < 0.05). Aging did not change the level of skeletal muscle COX-1, while cPGES increased 45% and EP1 ( P < 0.1), EP3, and EP4 decreased ∼33% ( P < 0.05). In summary, PGE2 production capacity and receptor levels are different in human skeletal muscles with markedly different type I and II muscle fiber composition. In aging skeletal muscle, PGE2 production capacity is elevated and receptor levels are downregulated. These findings have implications for understanding the regulation of skeletal muscle adaptations to exercise and aging by the PGE2/COX pathway and related inhibitors.

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Baguet, Audrey, Harmen Reyngoudt, Andries Pottier, Inge Everaert, Stefanie Callens, Eric Achten, and Wim Derave. "Carnosine loading and washout in human skeletal muscles." Journal of Applied Physiology 106, no. 3 (March 2009): 837–42. http://dx.doi.org/10.1152/japplphysiol.91357.2008.

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Carnosine (β-alanyl-l-histidine) is present in high concentrations in human skeletal muscles. The oral ingestion of β-alanine, the rate-limiting precursor in carnosine synthesis, has been shown to elevate the muscle carnosine content both in trained and untrained humans. Little human data exist about the dynamics of the muscle carnosine content, its metabolic regulation, and its dependence on muscle fiber type. The present study aimed to investigate in three skeletal muscle types the supplementation-induced amplitude of carnosine synthesis and its subsequent elimination on cessation of supplementation (washout). Fifteen untrained males participated in a placebo-controlled double-blind study. They were supplemented for 5–6 wk with either 4.8 g/day β-alanine or placebo. Muscle carnosine was quantified in soleus, tibialis anterior, and medial head of the gastrocnemius by proton magnetic resonance spectroscopy (MRS), before and after supplementation and 3 and 9 wk into washout. The β-alanine supplementation significantly increased the carnosine content in soleus by 39%, in tibialis by 27%, and in gastrocnemius by 23% and declined postsupplementation at a rate of 2–4%/wk. Average muscle carnosine remained increased compared with baseline at 3 wk of washout (only one-third of the supplementation-induced increase had disappeared) and returned to baseline values within 9 wk at group level. Following subdivision into high responders (+55%) and low responders (+15%), washout period was 15 and 6 wk, respectively. In the placebo group, carnosine remained relatively constant with variation coefficients of 9–15% over a 3-mo period. It can be concluded that carnosine is a stable compound in human skeletal muscle, confirming the absence of carnosinase in myocytes. The present study shows that washout periods for crossover designs in supplementation studies for muscle metabolites may sometimes require months rather than weeks.

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Kitai, N., Y. Fujii, S. Murakami, S. Furukawa, S. Kreiborg, and K. Takada. "Human Masticatory Muscle Volume and Zygomatico-mandibular Form in Adults with Mandibular Prognathism." Journal of Dental Research 81, no. 11 (November 2002): 752–56. http://dx.doi.org/10.1177/0810752.

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Although several investigators have reported associations between masticatory muscles and skeletal craniofacial form, there is no agreement on the association. We tested the hypothesis that masticatory muscle volume correlates with the size and form of the adjacent local skeletal sites. For this purpose, we investigated the morphological association of the cross-sectional area and volume of temporal and masseter muscles with zygomatico-mandibular skeletal structures using computerized tomography (CT) in 25 male adults with mandibular prognathism. Muscle variables significantly correlated with widths of the bizygomatic arch and temporal fossa but not with the cranium width. Masseter volume significantly correlated with cross-sectional areas of the zygomatic arch and mandibular ramus. Masseter orientation was almost perpendicular to the zygomatic arch and mandibular antegonial region. The zygomatic arch angle significantly correlated with the antegonial angle. The results of the study suggest that the masticatory muscles exert influence on the adjacent local skeletal sites.

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Ay, Birol, Erdal Karaoz, Cumhur C. Kesemenli, and Halime Kenar. "Skeletal muscle patch engineering on synthetic and acellular human skeletal muscle originated scaffolds." Journal of Biomedical Materials Research Part A 105, no. 3 (December 5, 2016): 879–90. http://dx.doi.org/10.1002/jbm.a.35948.

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Gregory, Chris M., and C. Scott Bickel. "Recruitment Patterns in Human Skeletal Muscle During Electrical Stimulation." Physical Therapy 85, no. 4 (April 1, 2005): 358–64. http://dx.doi.org/10.1093/ptj/85.4.358.

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Abstract Electromyostimulation (EMS) incorporates the use of electrical current to activate skeletal muscle and facilitate contraction. It is commonly used in clinical settings to mimic voluntary contractions and enhance the rehabilitation of human skeletal muscles. Although the beneficial effects of EMS are widely accepted, discrepancies concerning the specific responses to EMS versus voluntary actions exist. The unique effects of EMS have been attributed to several mechanisms, most notably a reversal of the recruitment pattern typically associated with voluntary muscle activation. This perspective outlines the authors' contention that electrical stimulation recruits motor units in a nonselective, spatially fixed, and temporally synchronous pattern. Furthermore, it synthesizes the evidence that supports the contention that this recruitment pattern contributes to increased muscle fatigue when compared with voluntary actions. The authors believe the majority of evidence suggests that EMS-induced motor unit recruitment is nonselective and that muscle fibers are recruited without obvious sequencing related to fiber types.

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Binder-Macleod, S. A., and S. C. Lee. "Catchlike property of human muscle during isovelocity movements." Journal of Applied Physiology 80, no. 6 (June 1, 1996): 2051–59. http://dx.doi.org/10.1152/jappl.1996.80.6.2051.

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This study examined the catchlike property of skeletal muscle during eccentric and concentric isovelocity contractions of fresh and fatigued quadriceps femoris muscles of 10 healthy subjects. During concentric contractions of fresh muscles, stimulation trains that elicited a catchlike response (CITs) produced greater force outputs and rates of rise force than comparable constant-frequency trains. These enhancements became more pronounced during fatigue. CITs were less effective in enhancing forces during eccentric contractions but did improve the rates of rise of force. Overall, the CIT that produced the greatest augmentation had a 5-ms initial interpulse interval. Proposed mechanisms for the catchlike property involve enhanced muscle stiffness for more efficient transmission of tension and increased calcium release. These results suggest that stimulation trains that take advantage of the catchlike property of skeletal muscle may be helpful during clinical applications where neuromuscular electrical stimulation is used to restore function in patients with damaged central nervous systems.

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42

Balch, Ying. "Subculture human skeletal muscle cells to produce the cells with different Culture medium compositions." Clinical Research and Clinical Trials 3, no. 4 (April 30, 2021): 01–03. http://dx.doi.org/10.31579/2693-4779/036.

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This study aimed to subculture human skeletal muscle cells (HSkMC) using a culture medium with different compositions to determine the most efficient medium for the growth of the human skeletal muscle cells. The culture media was divided into three groups: Group1. An HSkMC growth medium. Group 2. An HSkMC growth medium + with 10% high glucose (GH). Group 3. An HSkMC growth medium + 10% fetal bovine serum (FBS). HSkMC from groups 1 to 3 gradually became round in shape and gathered in clusters. These changes differed between the groups. In group 3, the HSkMC clusters were more in numbers and gathered as significantly more prominent than in the other groups under the EVOS-Microscope shown. We concluded that by manipulating the composition of the culture medium, it is possible to induce HSkMC to promote the best growth.

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Shin, Min-Kyoung, Jin Seok Bang, Jeoung Eun Lee, Hoang-Dai Tran, Genehong Park, Dong Ryul Lee, and Junghyun Jo. "Generation of Skeletal Muscle Organoids from Human Pluripotent Stem Cells to Model Myogenesis and Muscle Regeneration." International Journal of Molecular Sciences 23, no. 9 (May 4, 2022): 5108. http://dx.doi.org/10.3390/ijms23095108.

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In vitro organoids derived from human pluripotent stem cells (hPSCs) have been developed as essential tools to study the underlying mechanisms of human development and diseases owing to their structural and physiological similarity to corresponding organs. Despite recent advances, there are a few methodologies for three-dimensional (3D) skeletal muscle differentiation, which focus on the terminal differentiation into myofibers and investigate the potential of modeling neuromuscular disorders and muscular dystrophies. However, these methodologies cannot recapitulate the developmental processes and lack regenerative capacity. In this study, we developed a new method to differentiate hPSCs into a 3D human skeletal muscle organoid (hSkMO). This organoid model could recapitulate the myogenesis process and possesses regenerative capacities of sustainable satellite cells (SCs), which are adult muscle stem/progenitor cells capable of self-renewal and myogenic differentiation. Our 3D model demonstrated myogenesis through the sequential occurrence of multiple myogenic cell types from SCs to myocytes. Notably, we detected quiescent, non-dividing SCs throughout the hSkMO differentiation in long-term culture. They were activated and differentiated to reconstitute muscle tissue upon damage. Thus, hSkMOs can recapitulate human skeletal muscle development and regeneration and may provide a new model for studying human skeletal muscles and related diseases.

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Paul, Angelika C., and Nadia Rosenthal. "Different modes of hypertrophy in skeletal muscle fibers." Journal of Cell Biology 156, no. 4 (February 11, 2002): 751–60. http://dx.doi.org/10.1083/jcb.200105147.

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Skeletal muscles display a remarkable diversity in their arrangement of fibers into fascicles and in their patterns of innervation, depending on functional requirements and species differences. Most human muscle fascicles, despite their great length, consist of fibers that extend continuously from one tendon to the other with a single nerve endplate band. Other mammalian muscles have multiple endplate bands and fibers that do not insert into both tendons but terminate intrafascicularly. We investigated whether these alternate structural features may dictate different modes of cell hypertrophy in two mouse gracilis muscles, in response to expression of a muscle-specific insulin-like growth factor (IGF)-1 transgene (mIGF-1) or to chronic exercise. Both hypertrophic stimuli independently activated GATA-2 expression and increased muscle cross-sectional area in both muscle types, with additive effects in exercising myosin light chain/mIGF transgenic mice, but without increasing fiber number. In singly innervated gracilis posterior muscle, hypertrophy was characterized by a greater average diameter of individual fibers, and centralized nuclei. In contrast, hypertrophic gracilis anterior muscle, which is multiply innervated, contained longer muscle fibers, with no increase in average diameter, or in centralized nuclei. Different modes of muscle hypertrophy in domestic and laboratory animals have important implications for building appropriate models of human neuromuscular disease.

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Deane, Colleen S., Daniel J. Wilkinson, Bethan E. Phillips, Kenneth Smith, Timothy Etheridge, and Philip J. Atherton. "“Nutraceuticals” in relation to human skeletal muscle and exercise." American Journal of Physiology-Endocrinology and Metabolism 312, no. 4 (April 1, 2017): E282—E299. http://dx.doi.org/10.1152/ajpendo.00230.2016.

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Skeletal muscles have a fundamental role in locomotion and whole body metabolism, with muscle mass and quality being linked to improved health and even lifespan. Optimizing nutrition in combination with exercise is considered an established, effective ergogenic practice for athletic performance. Importantly, exercise and nutritional approaches also remain arguably the most effective countermeasure for muscle dysfunction associated with aging and numerous clinical conditions, e.g., cancer cachexia, COPD, and organ failure, via engendering favorable adaptations such as increased muscle mass and oxidative capacity. Therefore, it is important to consider the effects of established and novel effectors of muscle mass, function, and metabolism in relation to nutrition and exercise. To address this gap, in this review, we detail existing evidence surrounding the efficacy of a nonexhaustive list of macronutrient, micronutrient, and “nutraceutical” compounds alone and in combination with exercise in relation to skeletal muscle mass, metabolism (protein and fuel), and exercise performance (i.e., strength and endurance capacity). It has long been established that macronutrients have specific roles and impact upon protein metabolism and exercise performance, (i.e., protein positively influences muscle mass and protein metabolism), whereas carbohydrate and fat intakes can influence fuel metabolism and exercise performance. Regarding novel nutraceuticals, we show that the following ones in particular may have effects in relation to 1) muscle mass/protein metabolism: leucine, hydroxyl β-methylbutyrate, creatine, vitamin-D, ursolic acid, and phosphatidic acid; and 2) exercise performance: (i.e., strength or endurance capacity): hydroxyl β-methylbutyrate, carnitine, creatine, nitrates, and β-alanine.

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MacLeod, A. R., and C. Gooding. "Human hTM alpha gene: expression in muscle and nonmuscle tissue." Molecular and Cellular Biology 8, no. 1 (January 1988): 433–40. http://dx.doi.org/10.1128/mcb.8.1.433-440.1988.

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We have isolated a cDNA clone from a human skeletal muscle library which contains the complete protein-coding sequence of a skeletal muscle alpha-tropomyosin. This cDNA sequence defines a fourth human tropomyosin gene, the hTM alpha gene, which is distinct from the hTMnm gene encoding a closely related isoform of skeletal muscle alpha-tropomyosin. In cultured human fibroblasts, the hTM alpha gene encodes both skeletal-muscle- and smooth-muscle-type alpha-tropomyosins by using an alternative mRNA-splicing mechanism.

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MacLeod, A. R., and C. Gooding. "Human hTM alpha gene: expression in muscle and nonmuscle tissue." Molecular and Cellular Biology 8, no. 1 (January 1988): 433–40. http://dx.doi.org/10.1128/mcb.8.1.433.

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We have isolated a cDNA clone from a human skeletal muscle library which contains the complete protein-coding sequence of a skeletal muscle alpha-tropomyosin. This cDNA sequence defines a fourth human tropomyosin gene, the hTM alpha gene, which is distinct from the hTMnm gene encoding a closely related isoform of skeletal muscle alpha-tropomyosin. In cultured human fibroblasts, the hTM alpha gene encodes both skeletal-muscle- and smooth-muscle-type alpha-tropomyosins by using an alternative mRNA-splicing mechanism.

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Flis, Damian Jozef, Katarzyna Dzik, Jan Jacek Kaczor, Karol Cieminski, Malgorzata Halon-Golabek, Jedrzej Antosiewicz, Mariusz Roman Wieckowski, and Wieslaw Ziolkowski. "Swim Training Modulates Mouse Skeletal Muscle Energy Metabolism and Ameliorates Reduction in Grip Strength in a Mouse Model of Amyotrophic Lateral Sclerosis." International Journal of Molecular Sciences 20, no. 2 (January 9, 2019): 233. http://dx.doi.org/10.3390/ijms20020233.

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Metabolic reprogramming in skeletal muscles in the human and animal models of amyotrophic lateral sclerosis (ALS) may be an important factor in the diseases progression. We hypothesized that swim training, a modulator of cellular metabolism via changes in muscle bioenergetics and oxidative stress, ameliorates the reduction in muscle strength in ALS mice. In this study, we used transgenic male mice with the G93A human SOD1 mutation B6SJL-Tg (SOD1G93A) 1Gur/J and wild type B6SJL (WT) mice. Mice were subjected to a grip strength test and isolated skeletal muscle mitochondria were used to perform high-resolution respirometry. Moreover, the activities of enzymes involved in the oxidative energy metabolism and total sulfhydryl groups (as an oxidative stress marker) were evaluated in skeletal muscle. ALS reduces muscle strength (−70% between 11 and 15 weeks, p < 0.05), modulates muscle metabolism through lowering citrate synthase (CS) (−30% vs. WT, p = 0.0007) and increasing cytochrome c oxidase and malate dehydrogenase activities, and elevates oxidative stress markers in skeletal muscle. Swim training slows the reduction in muscle strength (−5% between 11 and 15 weeks) and increases CS activity (+26% vs. ALS I, p = 0.0048). Our findings indicate that swim training is a modulator of skeletal muscle energy metabolism with concomitant improvement of skeletal muscle function in ALS mice.

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Truskey, George A. "Development and application of human skeletal muscle microphysiological systems." Lab on a Chip 18, no. 20 (2018): 3061–73. http://dx.doi.org/10.1039/c8lc00553b.

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Human microphysiological systems were developed to model skeletal muscle and nerve-skeletal muscle interactions. These systems can be applied to a number of major disease states involve skeletal muscle, including type 2 diabetes, muscular dystrophy, sarcopenia and cachexia arising from cancer or heart disease.

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Lieber, Richard L., and Samuel R. Ward. "Skeletal muscle design to meet functional demands." Philosophical Transactions of the Royal Society B: Biological Sciences 366, no. 1570 (May 27, 2011): 1466–76. http://dx.doi.org/10.1098/rstb.2010.0316.

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Skeletal muscles are length- and velocity-sensitive force producers, constructed of a vast array of sarcomeres. Muscles come in a variety of sizes and shapes to accomplish a wide variety of tasks. How does muscle design match task performance? In this review, we outline muscle's basic properties and strategies that are used to produce movement. Several examples are provided, primarily for human muscles, in which skeletal muscle architecture and moment arms are tailored to a particular performance requirement. In addition, the concept that muscles may have a preferred sarcomere length operating range is also introduced. Taken together, the case is made that muscles can be fine-tuned to perform specific tasks that require actuators with a wide range of properties.

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Journal articles on the topic 'Human skeletal muscle'

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