Parvalbumin deficiency in fast-twitch muscles leads to increased 'slow-twitch type' mitochondria, but does not affect the expression of fiber specific proteins

The characteristics of transient contractures elicited by rapid cooling of frog or mouse muscles perfused in vitro with solutions equilibrated with 0.5–2.0% halothane are reviewed. The data indicate that these halothane-cooling contractures are dose dependent and reproducible, and their amplitude is larger in muscles containing predominantly slow-twitch type fibers, such as the mouse soleus, than in muscles in which fast-twitch fibers predominate, such as the mouse extensor digitorum longus. The halothane-cooling contractures are potentiated in muscles exposed to succinylcholine. The effects of Ca2+-free solutions, of the local anesthetics procaine, procainamide, and lidocaine, and of the muscle relaxant dantrolene on the halothane-cooling contractures are consistent with the proposal that the halothane-cooling contractures result from synergistic effects of halothane and low temperature on Ca sequestration by the sarcoplasmic reticulum. Preliminary results from skinned rabbit muscle fibers support this proposal. The halothane concentrations required for the halothane-cooling contractures of isolated frog or mouse muscles are comparable with those observed in serum of patients during general anesthesia. Accordingly, fascicles dissected from muscle biopsies of patients under halothane anesthesia for programmed surgery develop large contractures when rapidly cooled. The amplitude of these halothane-cooling contractures declined with the time of perfusion of the muscle fascicles in vitro with halothane-free physiological solutions. It is suggested that the halothane-cooling contractures could be used as a simple experimental model for the investigation of the effects of halothane on Ca homeostasis and contractility in skeletal muscle and for study of drugs of potential use in the management of the contractures associated with the halothane-induced malignant hyperthermia syndrome. It is shown that salicylates, but not indomethacin or mefenamic acid, inhibit the halothane-cooling contractures.

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The Functional Role of Calcineurin in Hypertrophy, Regeneration, and Disorders of Skeletal Muscle

Journal of Biomedicine and Biotechnology ◽

10.1155/2010/721219 ◽

2010 ◽

Vol 2010 ◽

pp. 1-8 ◽

Cited By ~ 50

Author(s):

Kunihiro Sakuma ◽

Akihiko Yamaguchi

Keyword(s):

Skeletal Muscle ◽

Functional Role ◽

Muscular Hypertrophy ◽

Growth And Remodeling ◽

Muscular Disorders ◽

Slow Twitch ◽

Fast Twitch ◽

Calcineurin Activity ◽

Muscle Remodeling

Skeletal muscle uses calcium as a second messenger to respond and adapt to environmental stimuli. Elevations in intracellular calcium levels activate calcineurin, a serine/threonine phosphatase, resulting in the expression of a set of genes involved in the maintenance, growth, and remodeling of skeletal muscle. In this review, we discuss the effects of calcineurin activity on hypertrophy, regeneration, and disorders of skeletal muscle. Calcineurin is a potent regulator of muscle remodeling, enhancing the differentiation through upregulation of myogenin or MEF2A and downregulation of the Id1 family and myostatin. Foxo may also be a downstream candidate for a calcineurin signaling molecule during muscle regeneration. The strategy of controlling the amount of calcineurin may be effective for the treatment of muscular disorders such as DMD, UCMD, and LGMD. Activation of calcineurin produces muscular hypertrophy of the slow-twitch soleus muscle but not fast-twitch muscles.

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Guinea pig soleus and gastrocnemius electromyograms at varying speeds, grades, and loads

Journal of Applied Physiology ◽

10.1152/jappl.1982.52.2.451 ◽

1982 ◽

Vol 52 (2) ◽

pp. 451-457 ◽

Cited By ~ 26

Author(s):

K. R. Gardiner ◽

P. F. Gardiner ◽

V. R. Edgerton

Keyword(s):

Guinea Pig ◽

Work Load ◽

Burst Duration ◽

Lateral Gastrocnemius ◽

Biochemical Alterations ◽

Hindlimb Muscles ◽

Slow Twitch ◽

Fast Twitch ◽

Grade Increase ◽

Emg Electrodes

The purpose of the study was to describe changes that occur in the usage of fast-twitch and slow-twitch guinea pig hindlimb muscles, as estimated using chronically implanted electromyogram (EMG) electrodes, during voluntary locomotion under various conditions. Guinea pigs, in which fine wire electrodes were implanted in soleus (SOL) and lateral gastrocnemius (LG) muscles, were exercised at various speeds (13.4, 26.8, 40.2 m/min), grades (0–30%) and in some conditions loads (50–150 g) on a motor-driven treadmill. Bipolar EMG signals were rectified-averaged (RA-EMG) and analyzed for burst duration, amplitude, and the integral of each burst (IEMG). For each condition and muscle, total IEMG/min (IEMG/step x steps/min) was calculated and expressed as a percent of the maximum IEMG recorded. With increasing speed at 0% grade, the ratio of LG to SOL IEMG, each expressed as percent of maximum, remained constant at about 0.82. An increased stepping rate of 150 (at 13.4 m/min) to 225 (at 40.2 m/min) steps/min was accompanied by a 37% decrease in burst duration in LG and SOL. When the treadmill belt speed was increased from 13.4 to 4.02 m/min at 30% grade, the LG/SOL ratio increased from 0.83 to 1.03, whereas burst duration decreased by 49% (SOL) and 51% (LG). Soleus IEMG did not change significantly with increases in speed or grade; LG IEMG increased significantly with speed at 10% grade and with grade increase at the highest speed (40.2 m/min). These data provide some insight into how modifications of work load on a treadmill affect overall muscle activity and may assist in the interpretation of training-induced muscle biochemical alterations previously noted by other investigators.

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Glutamine synthetase induction by glucocorticoids is preserved in skeletal muscle of aged rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1996.271.6.e1061 ◽

1996 ◽

Vol 271 (6) ◽

pp. E1061-E1066 ◽

Cited By ~ 15

Author(s):

D. Meynial-Denis ◽

M. Mignon ◽

A. Miri ◽

J. Imbert ◽

E. Aurousseau ◽

...

Keyword(s):

Skeletal Muscle ◽

Glutamine Synthetase ◽

Skeletal Muscles ◽

Female Rats ◽

Mrna Levels ◽

Aged Rats ◽

Adult Rats ◽

Adult Age ◽

Slow Twitch ◽

Fast Twitch

Glutamine synthetase (GS) is a glucocorticoid-inducible enzyme that has a key role for glutamine synthesis in muscle. We hypothesized that the glucocorticoid induction of GS could be altered in aged rats, because alterations in the responsiveness of some genes to glucocorticoids were reported in aging. We compared the glucocorticoid-induced GS in fast-twitch and slow-twitch skeletal muscles (tibialis anterior and soleus, respectively) and heart from adult (age 6-8 mo) and aged (age 22 mo) female rats. All animals received dexamethasone (Dex) in their drinking water (0.77 +/- 0.10 and 0.80 +/- 0.08 mg/day per adult and aged rat, respectively) for 5 days. Dex caused an increase in both GS activity and GS mRNA in fast-twitch and slow-twitch skeletal muscles from adult and aged rats. In contrast, Dex increased GS activity in heart of adult rats, without any concomitant change in GS mRNA levels. Furthermore, Dex did not affect GS activity in aged heart. Thus the responsiveness of GS to an excess of glucocorticoids is preserved in skeletal muscle but not in heart from aged animals.

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Lactate dehydrogenase isoenzymes: Distribution in fast-twitch red, fast-twitch white, and slow-twitch intermediate fibers of guinea pig skeletal muscle

Archives of Biochemistry and Biophysics ◽

10.1016/0003-9861(71)90482-6 ◽

1971 ◽

Vol 144 (1) ◽

pp. 304-307 ◽

Cited By ~ 30

Author(s):

J.B. Peter ◽

S. Sawaki ◽

R.J. Barnard ◽

V.R. Edgerton ◽

C.A. Gillespie

Keyword(s):

Skeletal Muscle ◽

Lactate Dehydrogenase ◽

Guinea Pig ◽

Slow Twitch ◽

Fast Twitch ◽

Lactate Dehydrogenase Isoenzymes

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Na current density at and away from end plates on rat fast- and slow-twitch skeletal muscle fibers

AJP Cell Physiology ◽

10.1152/ajpcell.1992.262.1.c229 ◽

1992 ◽

Vol 262 (1) ◽

pp. C229-C234 ◽

Cited By ~ 67

Author(s):

R. L. Ruff

Keyword(s):

Skeletal Muscle ◽

Current Density ◽

Muscle Fibers ◽

Postsynaptic Membrane ◽

Na Current ◽

End Plate ◽

Skeletal Muscle Fibers ◽

Slow Twitch ◽

Slow Twitch Fibers ◽

Fast Twitch

Na current density and membrane capacitance were studied with the loose patch voltage clamp technique on rat fast- and slow-twitch skeletal muscle fibers at three different regions on the fibers: 1) the end plate border, 2) greater than 200 microns from the end plate (extrajunctional), and 3) on the end plate postsynaptic membrane. Fibers were treated with collagenase to improve visualization of the end plate and to enzymatically remove the nerve terminal. The capacitance of membrane patches was similar on fast- and slow-twitch fibers and patches of membrane on the end plate had twice the capacitance of patches elsewhere. For fast- and slow-twitch fibers, the sizes of the Na current normalized to the area of the patch were as follows: end plate greater than end plate border greater than extrajunctional. For both types of fibers, the amplitudes of the Na current normalized to the capacitance of the membrane patch were as follows: end plate approximately end plate border greater than extrajunctional. At each of the three regions, the Na current densities were larger on fast-twitch fibers and fast-twitch fibers had a larger increase in Na current density at the end plate border compared with extrajunctional membrane.

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lncRNA-Six1 Is a Target of miR-1611 that Functions as a ceRNA to Regulate Six1 Protein Expression and Fiber Type Switching in Chicken Myogenesis

Cells ◽

10.3390/cells7120243 ◽

2018 ◽

Vol 7 (12) ◽

pp. 243 ◽

Cited By ~ 10

Author(s):

Manting Ma ◽

Bolin Cai ◽

Liang Jiang ◽

Bahareldin Ali Abdalla ◽

Zhenhui Li ◽

...

Keyword(s):

Fiber Type ◽

Muscle Fibers ◽

Muscle Fiber Types ◽

Fiber Types ◽

Proliferation And Differentiation ◽

Slow Twitch Muscle ◽

Fast Twitch Muscle ◽

Slow Twitch ◽

Slow Twitch Fibers ◽

Fast Twitch

Emerging studies indicate important roles for non-coding RNAs (ncRNAs) as essential regulators in myogenesis, but relatively less is known about their function. In our previous study, we found that lncRNA-Six1 can regulate Six1 in cis to participate in myogenesis. Here, we studied a microRNA (miRNA) that is specifically expressed in chickens (miR-1611). Interestingly, miR-1611 was found to contain potential binding sites for both lncRNA-Six1 and Six1, and it can interact with lncRNA-Six1 to regulate Six1 expression. Overexpression of miR-1611 represses the proliferation and differentiation of myoblasts. Moreover, miR-1611 is highly expressed in slow-twitch fibers, and it drives the transformation of fast-twitch muscle fibers to slow-twitch muscle fibers. Together, these data demonstrate that miR-1611 can mediate the regulation of Six1 by lncRNA-Six1, thereby affecting proliferation and differentiation of myoblasts and transformation of muscle fiber types.

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A combination of MEF3 and NFI proteins activates transcription in a subset of fast-twitch muscles.

Molecular and Cellular Biology ◽

10.1128/mcb.17.2.656 ◽

1997 ◽

Vol 17 (2) ◽

pp. 656-666 ◽

Cited By ~ 51

Author(s):

F Spitz ◽

M Salminen ◽

J Demignon ◽

A Kahn ◽

D Daegelen ◽

...

Keyword(s):

Regulatory Elements ◽

Specific Expression ◽

Transgenic Lines ◽

Slow Twitch ◽

Myogenic Factors ◽

Fast Twitch ◽

Restricted Pattern ◽

Aldolase A ◽

Drive Reporter Gene Expression

The human aldolase A pM promoter is active in fast-twitch muscles. To understand the role of the different transcription factors which bind to this promoter and determine which ones are responsible for its restricted pattern of expression, we analyzed several transgenic lines harboring different combinations of pM regulatory elements. We show that muscle-specific expression can be achieved without any binding sites for the myogenic factors MyoD and MEF2 and that a 64-bp fragment comprising a MEF3 motif and an NFI binding site is sufficient to drive reporter gene expression in some but, interestingly, not all fast-twitch muscles. A result related to this pattern of expression is that some isoforms of NFI proteins accumulate differentially in fast- and slow-twitch muscles and in distinct fast-twitch muscles. We propose that these isoforms of NFI proteins might provide a molecular basis for skeletal muscle diversity.

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Fibre-type specific modification of the activity and regulation of skeletal muscle pyruvate dehydrogenase kinase (PDK) by prolonged starvation and refeeding is associated with targeted regulation of PDK isoenzyme 4 expression

Biochemical Journal ◽

10.1042/bj3460651 ◽

2000 ◽

Vol 346 (3) ◽

pp. 651-657 ◽

Cited By ~ 47

Author(s):

Mary C. SUGDEN ◽

Alexandra KRAUS ◽

Robert A. HARRIS ◽

Mark J. HOLNESS

Keyword(s):

Skeletal Muscle ◽

Protein Expression ◽

Pyruvate Dehydrogenase ◽

Tricarboxylic Acid Cycle ◽

Tricarboxylic Acid ◽

Pyruvate Dehydrogenase Kinase ◽

Acid Cycle ◽

Slow Twitch ◽

Fast Twitch ◽

Anterior Tibialis

Using immunoblot analysis with antibodies raised against recombinant pyruvate dehydrogenase kinase (PDK) isoenzymes PDK2 and PDK4, we demonstrate selective changes in PDK isoenzyme expression in slow-twitch versus fast-twitch skeletal muscle types in response to prolonged (48 h) starvation and refeeding after starvation. Starvation increased PDK activity in both slow-twitch (soleus) and fast-twitch (anterior tibialis) skeletal muscle and was associated with loss of sensitivity of PDK to inhibition by pyruvate, with a greater effect in anterior tibialis. Starvation significantly increased PDK4 protein expression in both soleus and anterior tibialis, with a greater response in anterior tibialis. Starvation did not effect PDK2 protein expression in soleus, but modestly increased PDK2 expression in anterior tibialis. Refeeding for 4 h partially reversed the effect of 48-h starvation on PDK activity and PDK4 expression in both soleus and anterior tibialis, but the response was more marked in soleus than in anterior tibialis. Pyruvate sensitivity of PDK activity was also partially restored by refeeding, again with the greater response in soleus. It is concluded that targeted regulation of PDK4 isoenzyme expression in skeletal muscle in response to starvation and refeeding underlies the modulation of the regulatory characteristics of PDK in vivo. We propose that switching from a pyruvate-sensitive to a pyruvate-insensitive PDK isoenzyme in starvation (a) maintains a sufficiently high pyruvate concentration to ensure that the glucose → alanine → glucose cycle is not impaired, and (b) may ‘spare’ pyruvate for anaplerotic entry into the tricarboxylic acid cycle to support the entry of acetyl-CoA derived from fatty acid (FA) oxidation into the tricarboxylic acid cycle. We further speculate that FA oxidation by skeletal muscle is both forced and facilitated by upregulation of PDK4, which is perceived as an essential component of the operation of the glucose-FA cycle in starvation.

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