CHANGES IN SKELETAL MUSCLE SATELLITE CELLS DURING AGING

老年性肌肉萎缩是与以下疾病相关的主要问题之一 衰老，以失去力量和肌肉质量为特征。这些 变化最终限制了流动性，并因此限制了 我们社会中日益增长的一部分。这项拟议的研究将探讨 骨骼肌在衰老过程中发生的细胞和分子变化。 这些实验将重点放在骨骼肌的体外活性上。 卫星细胞，负责肌肉肥大的细胞和 再生。卫星细胞是肌肉前体细胞，存在于 出生后肌肉，并具有分化、分化和添加新的能力 在肥大过程中，从细胞核到现有的纤维。他们也有能力 在再生过程中形成全新的纤维。因为……的重要性 这些细胞在肌肉肥大、卫星能力减弱 老年肌肉中对正常生理信号做出反应的细胞可以发挥作用 在老年人肌肉无力维持中起主要作用 质量。在拟议的实验中，来自三个年龄段的供体大鼠， 年轻人，成年人和老年人，将被用来调查 生长抑素样肽对卫星细胞增殖活性的影响 蛋白质，增殖刺激活性(MSA)。此外, 这种激素与卫星细胞相互作用的年龄相关变化 将通过测定MSA受体的亲和力来研究 MSA的卫星细胞，每个细胞存在的受体数量和 激素受体复合体内化的速率。这项研究 该计划旨在提供对蜂窝和 肌肉衰老的分子机制，最终目的是贡献 以缓解与老年性肌肉萎缩相关的问题。

Senile muscle atrophy represents one of the major problems associated with aging and is characterized by loss of strength and muscle mass. These changes ultimately restrict mobility and, consequently, the independence of a growing segment of our society. The proposed research will probe cellular and molecular changes occurring in skeletal muscle during aging. These experiments will focus on the in vitro activity of skeletal muscle satellite cells, the cells responsible for muscle hypertrophy and regeneration. Satellite cells are muscle precursor cells that exist in postnatal muscle and have the ability to divide, differentiate and add new nuclei to existing fibers durng hypertrophy. They also have the ability to form entirely new fibers during regeneration. Because of the importance of these cells in muscle hypertrophy, the diminished capacity of satellite cells in old muscle to respond to normal physiological signals could play a major role in the inability of muscle in older individuals to maintain mass. In the proposed experiments, donor rats from three age groups, young, adult and old, will be used to investigate changes in the proliferative activity of satellite cells in response to a somatomedin-like protein, multiplication stimulating activity (MSA). In addition, age-related changes in the interaction of this hormone with satellite cells will be investigated by determining the affinity of MSA receptors on satellite cells for MSA, the number of receptors present per cell and the rate of internalization of the hormone receptor complex. This research program is designed to provide fundamental insights into the cellular and molecular mechanisms of muscle aging with the ultimate goal of contributing toward the alleviation of problems associated with senile muscle atrophy.