Muscle hypertrophy and the regenerative potential in skeletal muscles induced by the activation of tissue-specific stem

点击翻译按钮获取中文摘要

Skeletal muscles have a large plasticity in response to external stimuli. Skeletal muscle-specific stem cells, so-called satellite cells, play an important role in the plasticity of skeletal muscles. The activation of satellite cells occurs during not only the regeneration of injured skeletal muscles but also the regrowth of atrophied skeletal muscles. Therefore, the activation of satellite cells could prevent muscle atrophy in response to aging, an inactivity and a disuse. The purpose of the present study was to elucidate the role(s) and the source of satellite cells in the regenerative potential of the skeletal muscles and to investigate the regulatory factors for the regenerative potential of injured and uninjured skeletal muscles. The main results of the present study as fellow ; 1) hypertrophic stimuli could facilitates the regenerative process of injured skeletal muscles, 2) bone marrow stem cells may participate in the regeneration of injured skeletal muscles, 3) the intracellular signals, which enhanced the regenerative potential, were stimulated by heat-stress, estrogen and mechanical stress, 4) the up-regulation of heat shock protein 72 would stimulate the intracellular signals, which induced skeletal muscle hypertrophy. Evidences strongly suggest that stress response-associated intracellular as well as extracellular signals could enhance the regenerative potential of skeletal muscles via the activation of muscle satellite cells as well as the stimulation of the mobilization of stem cells from other stem cells sources. These evidences may be useful for the developments of the countermeasures for muscle atrophy, the specific method for muscle hypertrophy, and the rehabilitation technique to facilitate the regeneration of injured skeletal muscles in sports sciences as well as rehabilitation medicine.