Ontogenetic, gravity-dependent development of rat soleus muscle

2001 ◽  
Vol 280 (4) ◽  
pp. C1008-C1016 ◽  
Author(s):  
Yoshinobu Ohira ◽  
Takato Tanaka ◽  
Tomoo Yoshinaga ◽  
Fuminori Kawano ◽  
Takeshi Nomura ◽  
...  
Keyword(s):  
Soleus Muscle ◽  
Weight Bearing ◽  
Postnatal Period ◽  
Hindlimb Unloading ◽  
Full Weight Bearing ◽  
Type I ◽  
Myosin Isoforms ◽  
Normal Transition ◽  
Postural Muscle ◽  
Rat Soleus Muscle

We tested the hypothesis that rat soleus muscle fiber growth and changes in myosin phenotype during the postnatal, preweaning period would be largely independent of weight bearing. The hindlimbs of one group of pups were unloaded intermittently from postnatal day 4 to day 21: the pups were isolated from the dam for 5 h during unloading and returned for nursing for 1 h. Control pups were either maintained with the dam as normal or put on an alternating feeding schedule as described above. The enlargement of mass (∼3 times), increase in myonuclear number (∼1.6 times) and myonuclear domain (∼2.6 times), and transformation toward a slow fiber phenotype (from 56 to 70% fibers expressing type I myosin heavy chain) observed in controls were inhibited by hindlimb unloading. These properties were normalized to control levels or higher within 1 mo of reambulation beginning immediately after the unloading period. Therefore, chronic unloading essentially stopped the ontogenetic developmental processes of 1) net increase in DNA available for transcription, 2) increase in amount of cytoplasm sustained by that DNA pool, and 3) normal transition of myosin isoforms that occur in some fibers from birth to weaning. It is concluded that normal ontogenetic development of a postural muscle is highly dependent on the gravitational environment even during the early postnatal period, when full weight-bearing activity is not routine.

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.

Skeletal muscle myostatin mRNA expression is fiber-type specific and increases during hindlimb unloading

1999 ◽  
Vol 277 (2) ◽  
pp. R601-R606 ◽  
Author(s):  
Christian J. Carlson ◽  
Frank W. Booth ◽  
Scott E. Gordon
Keyword(s):  
Skeletal Muscle ◽  
Muscle Mass ◽  
Soleus Muscle ◽  
Fiber Type ◽  
Weight Bearing ◽  
Mrna Abundance ◽  
Hindlimb Unloading ◽  
Negative Regulator ◽  
Type I ◽  
Mrna Levels

Transgenic mice lacking a functional myostatin (MSTN) gene demonstrate greater skeletal muscle mass resulting from muscle fiber hypertrophy and hyperplasia (McPherron, A. C., A. M. Lawler, and S.-J. Lee. Nature 387: 83–90, 1997). Therefore, we hypothesized that, in normal mice, MSTN may act as a negative regulator of muscle mass. Specifically, we hypothesized that the predominately slow (type I) soleus muscle, which demonstrates greater atrophy than the fast (type II) gastrocnemius-plantaris complex (Gast/PLT), would show more elevation in MSTN mRNA abundance during hindlimb unloading (HU). Surprisingly, MSTN mRNA was not detectable in weight-bearing or HU soleus muscle, which atrophied 42% by the 7th day of HU in female ICR mice. In contrast, MSTN mRNA was present in weight-bearing Gast/PLT muscle and was significantly elevated (67%) at 1 day but not at 3 or 7 days of HU. However, the Gast/PLT muscle had only atrophied 17% by the 7th day of HU. Because the soleus is composed only of type I and IIa fibers, whereas the Gast/PLT expresses type IId/x and IIb in addition to type I and IIa, it was necessary to perform a more careful analysis of the relationship between MSTN mRNA levels and myosin heavy-chain (MHC) isoform expression (as a marker of fiber type). A significant correlation ( r = 0.725, P < 0.0005) was noted between the percentage of MHC isoform IIb expression and MSTN mRNA abundance in several muscles of the mouse hindlimb. These results indicate that MSTN expression is not strongly associated with muscle atrophy induced by HU; however, it is strongly associated with MHC isoform IIb expression in normal muscle.

Role of weight-bearing function on expression of myosin isoforms during regeneration of rat soleus muscles

1996 ◽  
Vol 270 (3) ◽  
pp. C763-C771 ◽  
Author(s):  
X. A. Bigard ◽  
D. Merino ◽  
B. Serrurier ◽  
F. Lienhard ◽  
Y. C. Guezennec ◽  
...  
Keyword(s):  
Soleus Muscle ◽  
Weight Bearing ◽  
Muscle Fibers ◽  
Immunohistochemical Analysis ◽  
Normal Weight ◽  
Hindlimb Suspension ◽  
Myosin Isoforms ◽  
Homogeneous Population ◽  
Postural Load ◽  
Rat Soleus Muscle

The expression of myosin isoforms was studied in regenerated rat soleus muscle during either normal or altered postural activity. Regeneration was induced following injury by venom from the Notechis scutatus scutatus snake. Immunohistochemical analysis showed that, in regenerating soleus muscle after 3 wk of hindlimb suspension, nearly all fibers reacted positively with the myosin heavy chain (MHC) antibody associated with fast-twitch muscle fibers (fast MHC). When 3 wk of recovery with normal weight-bearing activity followed hindlimb suspension, the regeneration soleus muscle exhibited a nearly homogeneous staining with the MHC antibody associated with the slow-twitch muscle fibers (slow MHC). These findings were in accordance with quantitative analysis of the electrophoretic separation of the native myosin isoforms. Immunohistochemical data showed that removal of weight bearing in the 21-day old regenerated soleus muscles resulted in an increase in fast MHC expression. Together, the results of the present study clearly demonstrate that the postural load is an important component in the induction of slow MHC in regenerating muscle and that the control of the expression of MHC in muscle comprising a homogeneous population of fibers deriving from satellite cells appears more homogeneous and more complete than in a nondegenerated one.

Influence of chronic stretching upon rat soleus muscle during non-weight-bearing conditions

1994 ◽  
Vol 429 (2) ◽  
pp. 274-279 ◽  
Author(s):  
Damien Leterme ◽  
Corinne Cordonnier ◽  
Yvonne Mounier ◽  
Maurice Falempin
Keyword(s):  
Soleus Muscle ◽  
Weight Bearing ◽  
Rat Soleus Muscle

Time course of soleus muscle myosin expression during hindlimb suspension and recovery

1987 ◽  
Vol 63 (1) ◽  
pp. 130-137 ◽  
Author(s):  
D. B. Thomason ◽  
R. E. Herrick ◽  
D. Surdyka ◽  
K. M. Baldwin
Keyword(s):  
Protein Expression ◽  
Soleus Muscle ◽  
Time Course ◽  
Weight Bearing ◽  
Relative Proportion ◽  
Contractile Protein ◽  
Myosin Isoforms ◽  
Hindlimb Unweighting ◽  
Loss Of Weight ◽  
Myofibril Protein

This study examined the time course of adult rodent soleus muscle myofibril and myosin isoform protein expression after 4, 8, 16, 28, and 56 days of hindlimb unweighting by tail suspension (S). The time course of soleus muscle recovery (R) was also examined after 28 days of hindlimb unweighting with an additional 4, 8, 16, and 28 days of unrestricted cage activity. During suspension, soleus muscle myofibril protein rapidly decreased from 34.3 +/- 3.1 (1.96SE) mg/pair in the control (C) group to 6.9 +/- 1.4 (1.96SE) mg/pair in S (t = 56 days). The calculated first-order degradation rate constant for this loss was kd = 0.17 days-1 [half time (t1/2) = 4.1 days]. The estimated slow myosin (SM) isoform content decreased from 13.4 +/- 2.0 (1.96SE) mg/pair in C to 2.1 +/- 0.2 (1.96SE) mg/pair in S (kd = 0.19 days-1, t1/2 = 3.6 days). The relative proportion of other myosin isoforms was increased at 28 and 56 days of suspension, reflecting an apparent de novo synthesis and the loss of SM. Recovery of contractile protein after 28 days of suspension was slower for both the myofibril protein and the SM isoform (kd = 0.07 days-1, t1/2 = 10 days). These data suggest that loss of weight bearing specifically affected the mechanisms of contractile protein expression reflected in soleus muscle protein degradation processes. In addition, the expression of the myosin isoforms were apparently differentially affected by the loss of weight-bearing activity.

Muscle regeneration during hindlimb unloading results in a reduction in muscle size after reloading

2001 ◽  
Vol 91 (1) ◽  
pp. 183-190 ◽  
Author(s):  
P. E. Mozdziak ◽  
P. M. Pulvermacher ◽  
E. Schultz
Keyword(s):  
Mitotic Activity ◽  
Satellite Cell ◽  
Soleus Muscle ◽  
Weight Bearing ◽  
Weight Ratio ◽  
The Body ◽  
Hindlimb Unloading ◽  
Muscle Size ◽  
Unit Size ◽  
Muscle Weight

The hindlimb-unloading model was used to study the ability of muscle injured in a weightless environment to recover after reloading. Satellite cell mitotic activity and DNA unit size were determined in injured and intact soleus muscles from hindlimb-unloaded and age-matched weight-bearing rats at the conclusion of 28 days of hindlimb unloading, 2 wk after reloading, and 9 wk after reloading. The body weights of hindlimb-unloaded rats were significantly ( P < 0.05) less than those of weight-bearing rats at the conclusion of hindlimb unloading, but they were the same ( P > 0.05) as those of weight-bearing rats 2 and 9 wk after reloading. The soleus muscle weight, soleus muscle weight-to-body weight ratio, myofiber diameter, number of nuclei per millimeter, and DNA unit size were significantly ( P< 0.05) smaller for the injured soleus muscles from hindlimb-unloaded rats than for the soleus muscles from weight-bearing rats at each recovery time. Satellite cell mitotic activity was significantly ( P < 0.05) higher in the injured soleus muscles from hindlimb-unloaded rats than from weight-bearing rats 2 wk after reloading, but it was the same ( P > 0.05) as in the injured soleus muscles from weight-bearing rats 9 wk after reloading. The injured soleus muscles from hindlimb-unloaded rats failed to achieve weight-bearing muscle size 9 wk after reloading, because incomplete compensation for the decrease in myonuclear accretion and DNA unit size expansion occurred during the unloading period.

Mechanical stimulation of the plantar foot surface attenuates soleus muscle atrophy induced by hindlimb unloading in rats

2005 ◽  
Vol 99 (2) ◽  
pp. 739-746 ◽  
Author(s):  
Antonios Kyparos ◽  
Daniel L. Feeback ◽  
Charles S. Layne ◽  
Daniel A. Martinez ◽  
Mark S. F. Clarke
Keyword(s):  
Muscle Atrophy ◽  
Soleus Muscle ◽  
Gastrocnemius Muscle ◽  
Hindlimb Unloading ◽  
Medial Gastrocnemius ◽  
Type I ◽  
Cross Sectional ◽  
Plantar Surface ◽  
Male Wistar Rats ◽  
Medial Gastrocnemius Muscle

Unloading-induced muscle atrophy occurs in the aging population, bed-ridden patients, and astronauts. This study was designed to determine whether dynamic foot stimulation (DFS) applied to the plantar surface of the rat foot can serve as a countermeasure to soleus muscle atrophy normally observed in hindlimb unloaded (HU) rats. Forty-four mature (6 mo old), male Wistar rats were randomly assigned to ambulatory control, HU alone, HU with active DFS (i.e., plantar contact with active inflation), HU with passive DFS (i.e., plantar contact without active inflation), and HU while wearing a DFS boot with no plantar contact groups. Application of active DFS during HU significantly counteracted the atrophic response by preventing ∼85% of the reduction in type I myofiber cross-sectional area (CSA) in the soleus while preventing ∼57% of the reduction in type I myofiber CSA and 43% of the reduction in type IIA myofiber CSA of the medial gastrocnemius muscle. Wearing of a DFS boot without active inflation prevented myofiber atrophy in the soleus of HU animals in a fashion similar to that observed in HU animals that wore an actively inflated DFS boot. However, when a DFS boot without plantar surface contact was worn during HU, no significant protection from HU-induced myofiber atrophy was observed. These results illustrate that the application of mechanical foot stimulation to the plantar surface of the rat foot is an effective countermeasure to muscle atrophy induced by HU.

beta-MHC transgene expression in suspended and mechanically overloaded/suspended soleus muscle of transgenic mice

1997 ◽  
Vol 272 (5) ◽  
pp. R1552-R1561 ◽  
Author(s):  
J. J. McCarthy ◽  
A. M. Fox ◽  
G. L. Tsika ◽  
L. Gao ◽  
R. W. Tsika
Keyword(s):  
Transgenic Mice ◽  
Soleus Muscle ◽  
Transgene Expression ◽  
Specific Activity ◽  
Fiber Type ◽  
Weight Bearing ◽  
Troponin C ◽  
Hindlimb Suspension ◽  
Regulatory Sequences ◽  
Type I

Non-weight-bearing (NWB) activity [space flight and hindlimb suspension (HS)] results in the loss of soleus muscle mass, a slow-to-fast fiber-type conversion, and decreased beta-myosin heavy chain (beta-MHC) protein and mRNA expression. To identify beta-MHC promoter sequences required for decreased beta-MHC expression in response to HS, we have modified an existing noninvasive hindlimb unweighting model to accommodate the use of (transgenic) mice. After 2 wk of HS, body and muscle (soleus > gastrocnemius > plantaris) weights were decreased as was the proportion of histochemically classified type I fibers in HS soleus muscle. Northern blot analysis revealed decreases in endogenous mRNA representing beta-MHC, slow myosin light chain 1 and 2, and cardiac/slow troponin C, whereas those representing skeletal troponin C, muscle creatine kinase, and glyceraldehyde-3-phosphate dehydrogenase increased. Protein extracts prepared from HS soleus (SS) muscle of mice harboring transgenes comprised of 5.6 or 0.6 kilobase of wild type (wt) mouse beta-MHC promoter (beta 5.6 wt, beta 0.6wt) and those carrying the simultaneous mutation (mut) of the MCAT, C-rich, and beta e3 subregions (beta 5.6mut3, beta 0.6mut3) revealed decreases in chloramphenicol acetyltransferase (CAT) specific activity relative to respective controls. Decreased CAT mRNA was observed for transgene beta 5.6mut3, line 85. Two weeks of the simultaneous imposition of mechanical overload (synergist ablation) and HS (MOV/HS) countermanded the loss in absolute and normalized SS weight but did not decrease beta 0.6wt transgene expression. These transgenic results demonstrate that regulatory sequences within a 600-base pair beta-MHC promoter are sufficient to direct decreased transcription of beta-MHC transgenes after 2 wk of HS.

Sign in / Sign up

Export Citation Format

Share Document