Oxidation of myosin heavy chain and reduction in force production in hyperthyroid rat soleus

2006 ◽  
Vol 100 (5) ◽  
pp. 1520-1526 ◽  
Author(s):  
Takashi Yamada ◽  
Takaaki Mishima ◽  
Makoto Sakamoto ◽  
Minako Sugiyama ◽  
Satoshi Matsunaga ◽  
...  
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Protein Function ◽  
Force Production ◽  
Myofibrillar Protein ◽  
Oxidative Modification ◽  
Daily Injection ◽  
Reduction In Force ◽  
Force Reduction

We tested the hypothesis that a force reduction in hyperthyroid rat soleus muscle would be associated with oxidative modification in myosin heavy chain (MHC). Daily injection of thyroid hormone [3,5,3′-triiodo-l-thyronine (T3)] for 21 days depressed isometric forces of whole soleus muscle across a range of stimulus frequencies ( P < 0.01). In fiber bundles, hyperthyroidism also led to pronounced reductions ( P < 0.01) in both K+- and 4-chloro- m-cresol-induced contracture forces. The degrees of the reductions were similar between these two contractures that were induced by distinct reagents. Treatment with T3 elicited a significant decrease (∼14%; P < 0.05) in the relative content of MHC contained in myofibrillar proteins. The content of carbonyl groups in myofibrillar protein extracts was elevated ( P < 0.05) by ∼50% in T3-treated muscles. Immunoblot analyses on T3-treated muscles showed a greater increase (106%; P < 0.05) of the carbonyl content in MHC than in myofibrillar protein extracts. These data suggest that in hyperthyroidism the decrease in force production of skeletal muscles may stem primarily from failure in myofibrillar protein function resulting from oxidative modification of MHC.

Distribution of myosin heavy chain isoforms in non-weight-bearing rat soleus muscle fibers

1996 ◽  
Vol 81 (6) ◽  
pp. 2540-2546 ◽  
Author(s):  
Robert J. Talmadge ◽  
Roland R. Roy ◽  
V. Reggie Edgerton
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
De Novo ◽  
Weight Bearing ◽  
Muscle Fibers ◽  
Myosin Heavy Chain Isoforms ◽  
Hindlimb Suspension ◽  
Type I ◽  
Rat Soleus Muscle

Talmadge, Robert J., Roland R. Roy, and V. Reggie Edgerton.Distribution of myosin heavy chain isoforms in non-weight-bearing rat soleus muscle fibers. J. Appl. Physiol. 81(6): 2540–2546, 1996.—The effects of 14 days of spaceflight (SF) or hindlimb suspension (HS) (Cosmos 2044) on myosin heavy chain (MHC) isoform content of the rat soleus muscle and single muscle fibers were determined. On the basis of electrophoretic analyses, there was a de novo synthesis of type IIx MHC but no change in either type I or IIa MHC isoform proportions after either SF or HS compared with controls. The percentage of fibers containing only type I MHC decreased by 26 and 23%, and the percentage of fibers with multiple MHCs increased from 6% in controls to 32% in HS and 34% in SF rats. Type IIx MHC was always found in combination with another MHC or combination of MHCs; i.e., no fibers contained type IIx MHC exclusively. These data suggest that the expression of the normal complement of MHC isoforms in the adult rat soleus muscle is dependent, in part, on normal weight bearing and that the absence of weight bearing induces a shift toward type IIx MHC protein expression in the preexisting type I and IIa fibers of the soleus.

Myosin heavy chain turnover in cultured neonatal rat heart cells: effects of [Ca2+]i and contractile activity

1996 ◽  
Vol 271 (5) ◽  
pp. C1447-C1456 ◽  
Author(s):  
K. L. Byron ◽  
J. L. Puglisi ◽  
J. R. Holda ◽  
D. Eble ◽  
A. M. Samarel
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Protein Turnover ◽  
Ventricular Myocytes ◽  
Contractile Activity ◽  
Myofibrillar Protein ◽  
Neonatal Rat ◽  
Heart Cells ◽  
Cell Shortening ◽  
Rat Heart Cells

Blockade of L-type Ca2+ channels in spontaneously contracting cultured neonatal rat ventricular myocytes causes contractile arrest, myofibrillar disassembly, and accelerated myofibrillar protein turnover. To determine whether myofibrillar protein turnover. To determine whether myofibrillar atrophy results indirectly from loss of mechanical signals or directly from alterations in intracellular Ca2+ concentration ([Ca2+]i), contractile activity was inhibited with verapamil (10 microM) or 2,3-butanedione monoxime (BDM), and their effects on cell shortening, [Ca2+]i, and myosin heavy chain (MHC) turnover were assessed. Control cells demonstrated spontaneous [Ca2+]i transients (peak amplitude 232 +/- 15 nM, 1-2 Hz) and vigorous contractile activity. Verapamil inhibited shortening by eliminating spontaneous [Ca2+]i transients. Low concentrations of BDM (5.0-7.5 mM) had no effect on basal or peak [Ca2+]i transient amplitude but reduced cell shortening, whereas 10 mM BDM reduced both [Ca2+]i transient amplitude and shortening. Both agents inhibited MHC synthesis, but only verapamil accelerated MHC degradation. Thus MHC half-life does not change in parallel with contractile activity but rather more closely follows changes in [Ca2+]i. [Ca2+]i transients appear critical in maintaining myofibrillar assembly and preventing accelerated MHC proteolysis.

Recovery of the soleus muscle after short- and long-term disuse induced by hindlimb unloading: effects on the electrical properties and myosin heavy chain profile

2005 ◽  
Vol 18 (2) ◽  
pp. 356-365 ◽  
Author(s):  
Jean-François Desaphy ◽  
Sabata Pierno ◽  
Antonella Liantonio ◽  
Annamaria De Luca ◽  
M. Paola Didonna ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Hindlimb Unloading ◽  
Short And Long Term

scholarly journals Decreased specific force and power production of muscle fibers from myostatin-deficient mice are associated with a suppression of protein degradation

2011 ◽  
Vol 111 (1) ◽  
pp. 185-191 ◽  
Author(s):  
Christopher L. Mendias ◽  
Erdan Kayupov ◽  
Joshua R. Bradley ◽  
Susan V. Brooks ◽  
Dennis R. Claflin
Keyword(s):  
Myosin Heavy Chain ◽  
Muscle Mass ◽  
Heavy Chain ◽  
Extensor Digitorum Longus ◽  
Isometric Force ◽  
Muscle Fibers ◽  
Force Production ◽  
Sectional Area ◽  
Cross Sectional ◽  
Maximum Isometric Force

Myostatin ( MSTN) is a member of the transforming growth factor-β superfamily of cytokines and is a negative regulator of skeletal muscle mass. Compared with MSTN+/+ mice, the extensor digitorum longus muscles of MSTN−/− mice exhibit hypertrophy, hyperplasia, and greater maximum isometric force production (Fo), but decreased specific maximum isometric force (sFo; Fo normalized by muscle cross-sectional area). The reason for the reduction in sFo was not known. Studies in myotubes indicate that inhibiting myostatin may increase muscle mass by decreasing the expression of the E3 ubiquitin ligase atrogin-1, which could impact the force-generating capacity and size of muscle fibers. To gain a greater understanding of the influence of myostatin on muscle contractility, we determined the impact of myostatin deficiency on the contractility of permeabilized muscle fibers and on the levels of atrogin-1 and ubiquitinated myosin heavy chain in whole muscle. We hypothesized that single fibers from MSTN−/− mice have a greater Fo, but no difference in sFo, and a decrease in atrogin-1 and ubiquitin-tagged myosin heavy chain levels. The results indicated that fibers from MSTN−/− mice have a greater cross-sectional area, but do not have a greater Fo and have a sFo that is significantly lower than fibers from MSTN+/+ mice. The extensor digitorum longus muscles from MSTN−/− mice also have reduced levels of atrogin-1 and ubiquitinated myosin heavy chain. These findings suggest that myostatin inhibition in otherwise healthy muscle increases the size of muscle fibers and decreases atrogin-1 levels, but does not increase the force production of individual muscle fibers.

scholarly journals Cheap labor: myosin fiber type expression and enzyme activity in the forelimb musculature of sloths (Pilosa: Xenarthra)

2018 ◽  
Vol 125 (3) ◽  
pp. 799-811 ◽  
Author(s):  
Kyle B. Spainhower ◽  
Rebecca N. Cliffe ◽  
Allan K. Metz ◽  
Ernest M. Barkett ◽  
Paije M. Kiraly ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Citrate Synthase ◽  
Fiber Type ◽  
Force Production ◽  
Joint Torque ◽  
Muscle Properties ◽  
Large Joint ◽  
Forelimb Muscles

Sloths are canopy-dwelling inhabitants of American neotropical rainforests that exhibit suspensory behaviors. These abilities require both strength and muscular endurance to hang for extended periods of time; however, the skeletal muscle mass of sloths is reduced, thus requiring modifications to muscle architecture and leverage for large joint torque. We hypothesize that intrinsic muscle properties are also modified for fatigue resistance and predict a heterogeneous expression of slow/fast myosin heavy chain (MHC) fibers that utilize oxidative metabolic pathways for economic force production. MHC fiber type distribution and energy metabolism in the forelimb muscles of three-toed ( Bradypus variegatus, n = 5) and two-toed ( Choloepus hoffmanni, n = 4) sloths were evaluated using SDS-PAGE, immunohistochemistry, and enzyme activity assays. The results partially support our hypothesis by a primary expression of the slow MHC-1 isoform as well as moderate expression of fast MHC-2A fibers, whereas few hybrid MHC-1/2A fibers were found in both species. MHC-1 fibers were larger in cross-sectional area (CSA) than MHC-2A fibers and comprised the greatest percentage of CSA in each muscle sampled. Enzyme assays showed elevated activity for the anaerobic enzymes creatine kinase and lactate dehydrogenase compared with low activity for aerobic markers citrate synthase and 3-hydroxyacetyl CoA dehydrogenase. These findings suggest that sloth forelimb muscles may rely heavily on rapid ATP resynthesis pathways, and lactate accumulation may be beneficial. The intrinsic properties observed match well with suspensory requirements, and these modifications may have further evolved in unison with low metabolism and slow movement patterns as means to systemically conserve energy. NEW & NOTEWORTHY Myosin heavy chain (MHC) fiber type and fiber metabolic properties were evaluated to understand the ability of sloths to remain suspended for extended periods without muscle fatigue. Broad distributions of large, slow MHC-1 fibers as well as small, fast MHC-2A fibers are expressed in sloth forelimbs, but muscle metabolism is generally not correlated with myosin fiber type or body size. Sloth muscles rely on rapid, anaerobic pathways to resist fatigue and sustain force production.

scholarly journals Changes in myosin heavy chain mRNA and protein isoforms in single fibers of unloaded rat soleus muscle

FEBS Letters ◽  
1999 ◽  
Vol 463 (1-2) ◽  
pp. 15-18 ◽  
Author(s):  
Laurence Stevens ◽  
Bärbel Gohlsch ◽  
Yvonne Mounier ◽  
Dirk Pette
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Protein Isoforms ◽  
Single Fibers ◽  
Rat Soleus Muscle

scholarly journals Effect of thyroid hormone on the myosin heavy chain isoforms in slow and fast muscles of the rat.

1999 ◽  
Vol 46 (3) ◽  
pp. 823-835 ◽  
Author(s):  
A Jakubiec-Puka ◽  
I Ciechomska ◽  
U Mackiewicz ◽  
J Langford ◽  
H Chomontowska
Keyword(s):  
Thyroid Hormone ◽  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Myosin Heavy Chain Isoforms ◽  
Leg Muscles ◽  
Slow Twitch ◽  
Fast Twitch ◽  
Fast Muscles ◽  
Slow And Fast Muscles

The myosin heavy chain (MHC) was studied by biochemical methods in the slow-twitch (soleus) and two fast-twitch leg muscles of the triiodothyronine treated (hyperthyroid), thyroidectomized (hypothyroid) and euthyroid (control) rats. The changes in the contents of individual MHC isoforms(MHC-1, MHC-2A, MHC-2B and MHC-2X) were evaluated in relation to the muscle mass and the total MHC content. The MHC-1 content decreased in hyperthyreosis, while it increased in hypothyreosis in the soleus and in the fast muscles. The MHC-2A content increased in hyperthyreosis and it decreased in hypothyreosis in the soleus muscle. In the fast muscles hyperthyreosis did not affect the MHC-2A content, whereas hypothyreosis caused an increase in this MHC isoform content. The MHC-2X, present only in traces or undetected in the control soleus muscle, was synthesised in considerable amount in hyperthyreosis; in hypothyreosis the MHC-2X was not detected in the soleus. In the fast muscles the content of MHC-2X was not affected by any changes in the thyroid hormone level. The MHC-2B seemed to be not influenced by hyperthyreosis in the fast muscles, whereas the hypothyreosis caused a decrease of its content. In the soleus muscle the MHC-2B was not detected in any groups of rats. The results suggest that the amount of each of the four MHC isoforms expressed in the mature rat leg muscles is influenced by the thyroid hormone in a different way. The MHC-2A and the MHC-2X are differently regulated in the soleus and in the fast muscles; thyroid hormone seems to be necessary for expression of those isoforms in the soleus muscle.

AGE DEPENDENCE OF MYOSIN HEAVY CHAIN TRANSITIONS IN THE HINDLIMB UNLOADED SOLEUS MUSCLE

1998 ◽  
Vol 30 (Supplement) ◽  
pp. 206
Author(s):  
T. Okumoto ◽  
A. Saitoh ◽  
H. Nakano ◽  
S. Katsuta
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Age Dependence

In vivo regulation of the β-myosin heavy chain gene in soleus muscle of suspended and weight-bearing rats

2000 ◽  
Vol 278 (6) ◽  
pp. C1153-C1161 ◽  
Author(s):  
Julia M. Giger ◽  
Fadia Haddad ◽  
Anqi X. Qin ◽  
Kenneth M. Baldwin
Keyword(s):  
Myosin Heavy Chain ◽  
Soleus Muscle ◽  
Heavy Chain ◽  
Weight Bearing ◽  
Hindlimb Suspension ◽  
Luciferase Reporter ◽  
Chain Gene ◽  
Direct Gene Transfer ◽  
Luciferase Reporter Gene

In the weight-bearing hindlimb soleus muscle of the rat, ∼90% of muscle fibers express the β-myosin heavy chain (β-MHC) isoform protein. Hindlimb suspension (HS) causes the MHC isoform population to shift from β toward the fast MHC isoforms. Our aim was to establish a model to test the hypothesis that this shift in expression is transcriptionally regulated through specific cis elements of the β-MHC promoter. With the use of a direct gene transfer approach, we determined the activity of different length β-MHC promoter fragments, linked to a firefly luciferase reporter gene, in soleus muscle of control and HS rats. In weight-bearing rats, the relative luciferase activity of the longest β-promoter fragment (−3500 bp) was threefold higher than the shorter promoter constructs, which suggests that an enhancer sequence is present in the upstream promoter region. After 1 wk of HS, the reporter activities of the −3500-, −914-, and −408-bp promoter constructs were significantly reduced (∼40%), compared with the control muscles. However, using the −215-bp construct, no differences in promoter activity were observed between HS and control muscles, which indicates that the response to HS in the rodent appears to be regulated within the −408 and −215 bp of the promoter.

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