Skeletal muscle plays a pivotal role in locomotion and metabolism. Improper function of skeletal muscle, as seen in conditions such as degenerative myopathies and sarcopenia, has profound impacts on human health. Reversely, many human diseases, such as heart failure, chronic obstructive pulmonary disease and type 2 diabetes, cause impairment of skeletal muscle function. To break the vicious cycle, it is important to understand the molecular mechanisms underlying skeletal muscle repair. Skeletal muscle stem cells (also called satellite cells) serve as an important reservoir of myogenic cells that have the potential to accrete to, repair or even rejuvenate skeletal muscle fibers. The life-long maintenance of this potential relies on orchestrated satellite cell behaviors involving intricate balances between proliferation, differentiation and self- renewal. Accumulating evidence indicate that low oxygen tension (hypoxia) is a physiological stem cell niche factor that regulates stem cell behaviors. However, little is known about the impact of hypoxia and hypoxia- induced signaling on satellite cells and skeletal muscle repair. In the present study, we will 1) identify key factors that mediate the hypoxia signaling in satellite cells; 2) investigate key regulators that modulate satellite cell responses to hypoxia; and 3) explore novel therapeutic approaches that may improve skeletal muscle repair in physiological and human disease-relevant conditions. We expect results from this study will substantially contribute to the understanding of satellite cells and skeletal muscle repair, and also shed light on interventions for improving skeletal muscle health.

Public Health Relevance

Skeletal muscle atrophy and sarcopenia are significant public health problems facing millions of Americans. Skeletal muscle stem cells hold promise to ameliorate these muscle disease conditions by contributing to muscle growth and repair. The goal of this work is to identify systemic and molecular regulators of muscle stem cells and explore novel therapeutic approaches for skeletal muscle atrophy and sarcopenia.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR070178-02
Application #
9303877
Study Section
Skeletal Muscle and Exercise Physiology Study Section (SMEP)
Program Officer
Boyce, Amanda T
Project Start
2016-07-01
Project End
2021-06-30
Budget Start
2017-07-01
Budget End
2018-06-30
Support Year
2
Fiscal Year
2017
Total Cost
Indirect Cost
Name
University of Georgia
Department
Other Health Professions
Type
Organized Research Units
DUNS #
004315578
City
Athens
State
GA
Country
United States
Zip Code
30602
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