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Updated: Jan 15, 2026
Preparation and Culture of Myogenic Precursor Cells/Primary Myoblasts from Skeletal Muscle of Adult and Aged Humans
Published on: February 16, 2017
Enlargement of the muscle stem cell pool in linc-MYH-deficient mice does not prevent sarcopenia during aging
Qing Yin1, Christelle Labib1, Thomas Boettger1
1Department of Cardiac Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Bad Nauheim, Germany.
Abstract:
Loss of skeletal muscle mass and muscle strength during aging (sarcopenia) and reduced skeletal muscle regeneration are often attributed to the age-dependent decline of muscle stem cells (MuSCs). However, it has not been analyzed whether enlargement of the MuSC pool in old animals can attenuate sarcopenia or restore regenerative potential. Here, we directly tested this idea by taking advantage of linc-MYH-mutant mice, which show a substantially increased number of MuSCs in young mice. We found that 24-month-old geriatric linc-MYH knockout mice still maintain a consistently enlarged MuSC pool compared to age-matched controls. MuSCs in geriatric linc-MYH knockout mice were located beneath the basal lamina and remained mostly in a quiescent state. Importantly, enlargement of the MuSC pool did not prevent sarcopenia, or improve muscle function and regeneration. Instead, the larger MuSC pool in geriatric linc-MYH-/- mice resulted in the formation of smaller muscles during regeneration with thicker fibers, characterized by an increased myonuclei content per fiber. Furthermore, we observed shifts of the muscle fiber-type composition in linc-MYH-/- mice during aging, including a reduction of type IIb fibers in the tibialis anterior muscle and a reduction of type IIa fibers in the soleus, combined with an increase of type I fibers.
Insights
Enlarging the muscle stem cell (MuSC) pool in aging mice did not prevent sarcopenia or improve muscle regeneration. Instead, it led to smaller muscles with altered fiber types and increased myonuclei content.
Area of Science:
- Muscle stem cell biology
- Aging and regeneration
- Skeletal muscle physiology
Background:
- Sarcopenia, the age-related loss of muscle mass and strength, is linked to declining muscle stem cells (MuSCs).
- The impact of an enlarged MuSC pool on sarcopenia and muscle regeneration in aged individuals remains uninvestigated.
Purpose of the Study:
- To determine if an enlarged MuSC pool can mitigate age-related muscle decline and enhance regenerative capacity.
- To investigate the effects of a sustained larger MuSC pool on muscle function and structure in aged mice.
Main Methods:
- Utilized linc-MYH-mutant mice with a naturally enlarged MuSC pool.
- Compared 24-month-old geriatric linc-MYH knockout mice with age-matched controls.
- Assessed MuSC pool size, localization, quiescence, muscle regeneration, fiber type composition, and muscle function.
Main Results:
- Geriatric linc-MYH knockout mice maintained an enlarged MuSC pool, with cells remaining quiescent and beneath the basal lamina.
- An enlarged MuSC pool did not prevent sarcopenia or improve muscle regeneration and function.
- Regeneration in mice with enlarged MuSC pools resulted in smaller muscles, thicker fibers, and increased myonuclei per fiber.
- Observed shifts in muscle fiber types, including reduced type IIb and IIa fibers and increased type I fibers with aging.
Conclusions:
- An enlarged MuSC pool does not prevent or reverse age-related muscle loss (sarcopenia).
- Sustaining a larger MuSC pool can negatively impact muscle regeneration and fiber characteristics.
- Age-dependent alterations in muscle fiber type composition are influenced by MuSC pool size.
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