CHRNA1 induces sarcopenia through neuromuscular synaptic elimination
Zhiyin Liao1, Minghan Xiao2, Jinliang Chen1
1Department of Geriatrics, the First Affiliated Hospital of Chongqing Medical University, Friendship Road 1, Yuan Jiagang, 400016 Chongqing, China.
Experimental Gerontology
|July 9, 2022
Summary
Increased CHRNA1 expression in skeletal muscle contributes to sarcopenia, the age-related loss of muscle mass and function. This study shows CHRNA1 upregulation worsens muscle innervation decline and muscle atrophy in aging.
Area of Science:
- Gerontology
- Muscle Physiology
- Molecular Biology
Background:
- Sarcopenia significantly impacts elderly quality of life, with unclear molecular underpinnings.
- Age-related muscle innervation degeneration is linked to movement disorders and atrophy.
- CHRNA1 expression is elevated in elderly skeletal muscle and aging rodents.
Purpose of the Study:
- To investigate the role of CHRNA1 in the development and progression of sarcopenia.
- To determine if increased CHRNA1 expression induces sarcopenia.
Main Methods:
- Local injection of adeno-associated virus serotype 9 carrying CHRNA1 (AAV9-CHRNA1) into hindlimb muscles of rodents.
- Assessment of muscle innervation percentage.
- Measurement of skeletal muscle mass (gastrocnemius mass index, muscle fiber cross-sectional area).
- Evaluation of skeletal muscle function (compound muscle action potential, muscle contractility).
Main Results:
- AAV9-CHRNA1 injection decreased the percentage of muscle innervation.
- Skeletal muscle mass significantly decreased, evidenced by reduced gastrocnemius mass index and muscle fiber area.
- Skeletal muscle function declined, shown by decreased compound muscle action potential and contractility.
Conclusions:
- Upregulation of CHRNA1 induces and exacerbates sarcopenia.
- CHRNA1 plays a critical role in the pathogenesis of age-related muscle decline.
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