|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Kinesiology, University of Minnesota, Minneapolis, Minnesota, United States
2 Program in Physical Therapy, University of Minnesota, Minneapolis, Minnesota, United States
3 Physical Therapy, Georgia State University, Atlanta, Georgia, United States
* To whom correspondence should be addressed. E-mail: dl{at}ddt.biochem.umn.edu.
Skeletal muscle contractility and myosin function decline following ovariectomy in mature, female mice. In the present study we tested the hypothesis that estradiol-replacement can reverse those declines. Four month-old female C57BL/6 mice (n=69) were ovariectomized (OVX) or sham-operated (Sham). Some mice were treated immediately with placebo or 17
-estradiol (OVX+E2) while other mice were treated 30 days post-surgery. Thirty or sixty days post-surgery, soleus muscles were assessed in vitro for contractile function and susceptibility to eccentric contraction-induced injury. Myosin structural dynamics was analyzed in extensor digitorum longus (EDL)muscles by electron paramagnetic resonance spectroscopy. Maximal isometric tetanic force was affected by estradiol status (P<0.001) being ~10% less in soleus muscles from OVX compared with Sham mice [168 mN (SD 16.7) vs. 180 mN (SD 14.4)] and was restored in OVX+E2 mice [187 mN (SD 17.6)]. The fraction of strong-binding myosin during contraction was also affected (P=0.045) and was ~15% lower in EDL muscles from OVX compared with OVX+E2 mice [0.263 (SD 0.034) vs. 0.311 (SD 0.022)]. Plasma estradiol levels were correlated with Po (r=0.458; P<0.001) and active stiffness (r=0.329; P=0.044) indicating that circulating estradiol influenced muscle and myosin function. Estradiol was not effective in protecting muscle against an acute eccentric contraction-induced injury (P
0.401) but did restore ovariectomy-induced increases in muscle wet mass caused by fluid accumulation. Collectively, estradiol had a beneficial effect on female mouse skeletal muscle.
This article has been cited by other articles:
![]() |
S. M. Greising, K. A. Baltgalvis, D. A. Lowe, and G. L. Warren Hormone Therapy and Skeletal Muscle Strength: A Meta-Analysis J Gerontol A Biol Sci Med Sci, October 1, 2009; 64A(10): 1071 - 1081. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Komrakova, C. Werner, M. Wicke, B. T. Nguyen, S. Sehmisch, M. Tezval, K. M. Stuermer, and E. K. Stuermer Effect of daidzein, 4-methylbenzylidene camphor or estrogen on gastrocnemius muscle of osteoporotic rats undergoing tibia healing period J. Endocrinol., May 1, 2009; 201(2): 253 - 262. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Brown, J. Ning, J. A. Ferreira, J. L. Bogener, and D. B. Lubahn Estrogen receptor-{alpha} and -{beta} and aromatase knockout effects on lower limb muscle mass and contractile function in female mice Am J Physiol Endocrinol Metab, April 1, 2009; 296(4): E854 - E861. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Hubal and P. M. Clarkson Counterpoint: Estrogen and Sex do not Significantly Influence Post-Exercise Indexes of Muscle Damage, Inflammation, and Repair J Appl Physiol, March 1, 2009; 106(3): 1012 - 1014. [Full Text] [PDF] |
||||
![]() |
F. X. Pizza, B. C. Clark, R. E. De Meersman, S. M. Phillips, N. Stupka, S. Sipila, V. Kovanen, H. Suominen, G. L. Warren, D. A. Lowe, et al. Comments on Point:Counterpoint: Estrogen and sex do/do not influence post-exercise indexes of muscle damage, inflammation, and repair J Appl Physiol, March 1, 2009; 106(3): 1016 - 1020. [Full Text] [PDF] |
||||
![]() |
G. L. Warren, A. L. Moran, H. A. Hogan, A. S. Lin, R. E. Guldberg, and D. A. Lowe Voluntary run training but not estradiol deficiency alters the tibial bone-soleus muscle functional relationship in mice Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2007; 293(5): R2015 - R2026. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |