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Isolation of Human Myoblasts, Assessment of Myogenic Differentiation, and Store-operated Calcium Entry Measurement
Published on: July 26, 2017
Oestrogen receptor-alpha activation augments post-exercise myoblast proliferation
A Thomas1, K Bunyan, P M Tiidus
1Department of Kinesiology & PE and Faculty of Science, Wilfrid Laurier University, Waterloo, ON, Canada.
Acta Physiologica (Oxford, England)
|August 22, 2009
Summary
Oestrogen and a specific oestrogen receptor-alpha agonist (propyl pyrazole triol) significantly increase myoblast numbers and activation after exercise. This suggests oestrogen primarily acts via oestrogen receptor-alpha to enhance muscle repair post-exercise.
Area of Science:
- Muscle regeneration and repair
- Endocrinology and exercise physiology
Background:
- Oestrogen is known to augment myoblast (satellite cell) activation, proliferation, and total number.
- This effect is potentially mediated through oestrogen receptors (OR).
Purpose of the Study:
- To investigate the mechanism of oestrogen's influence on post-exercise myoblast numbers.
- To examine the role of the oestrogen receptor-alpha (OR-alpha) using a specific agonist, propyl pyrazole triol (PPT).
Main Methods:
- Ovariectomized rats (n=64) were divided into sham, oestrogen-supplemented, agonist-supplemented, and combined groups.
- Groups were further divided into control (unexercised) and exercise subgroups.
- Muscle samples were collected post-exercise and immunostained for myoblast markers Pax7 and MyoD.
Main Results:
- Exercise significantly increased total (Pax7+) and activated (MyoD+) myoblasts across all groups.
- Oestrogen and PPT supplementation (individually and combined) further augmented myoblast numbers and activation post-exercise.
- These augmentations were observed in white vastus and soleus muscles compared to unsupplemented animals.
Conclusions:
- Both oestrogen and the OR-alpha agonist PPT significantly increase myoblast number and activation post-exercise.
- Oestrogen appears to stimulate myoblast proliferation following exercise primarily through an OR-alpha-mediated mechanism.
- These findings highlight the role of oestrogen and its specific receptor in muscle repair after exercise-induced damage.
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