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Key Components of Human Myofibre Denervation and Neuromuscular Junction Stability are Modulated by Age and Exercise
Casper Soendenbroe1,2, Cecilie J L Bechshøft1,3, Mette F Heisterberg1
1Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery M, Bispebjerg Hospital, Building 8, Nielsine Nielsens vej 11, 2400 Copenhagen NV, Denmark.
Cells
|April 10, 2020
Summary
Exercise can help maintain neuromuscular junction (NMJ) stability in older adults by influencing acetylcholine receptor (AChR) gene expression. This study shows exercise promotes NMJ plasticity, counteracting age-related muscle decline.
Area of Science:
- Gerontology
- Neuroscience
- Exercise Physiology
Background:
- Aging leads to muscle mass and function decline, partly due to muscle fiber denervation.
- The neuromuscular junction (NMJ) is crucial for muscle function and is affected by aging.
- Understanding molecular targets of NMJ stability is vital for interventions in elderly individuals.
Purpose of the Study:
- To investigate exercise's potential to modulate molecular targets of NMJ stability in healthy elderly individuals.
- To examine age-related changes in NMJ molecular targets and the effects of a single exercise bout.
Main Methods:
- Resistance exercise was performed by young and elderly males and females.
- Muscle biopsies were collected post-exercise for analysis.
- Immunohistochemistry and RT-qPCR were used to analyze denervation and NMJ stability markers, including acetylcholine receptor (AChR) subunits.
Main Results:
- Elderly individuals showed more denervated fibers and altered AChR subunit gene expression compared to young individuals.
- A single exercise bout induced changes in AChR subunit gene expression, indicating NMJ plasticity in the elderly.
- Satellite cells in aged individuals exhibited reduced transcriptional capacity for AChR subunit genes.
Conclusions:
- Exercise can promote NMJ stability and plasticity in elderly individuals, even if previously inactive.
- Age-related decline affects NMJ molecular targets, but exercise interventions show promise.
- Satellite cell function for AChR gene expression is impaired by aging, highlighting a potential mechanism for muscle decline.
Keywords:
acetylcholine receptorcell culturedenervationheavy resistance exercisemyogenesisneonatal myosinneural cell adhesion moleculeneuromuscular junctionsarcopeniaMore Related Videos
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