Satellite Cells In Skeletal Muscle Hypertrophy

To address this issue a novel mouse strain pax7 dta was created which enabled the conditional ablation of 90 of satellite cells in mature skeletal muscle following tamoxifen administration.

Satellite cells in skeletal muscle hypertrophy.

This is a major research finding alas at the molecular level of muscle which shows that skeletal muscle fiber hypertrophy begins to occur before the addition of new muscle nuclei see figure 1. Gradams uci edu satellite cells are small mononuclear cells found in close association with striated skeletal muscles cells myofibers. These findings have led to a general consensus that satellite cell mediated myonuclear addition is likely an involved mechanism in promoting skeletal muscle hypertrophy and this hypothesis is further supported by studies which have illustrated high associations exist between fcsa and myonuclear number kadi et al 1999. Hormones in skeletal muscle hypertrophy hormones are chemicals which organs secrete to initiate or regulate the activity of an organ or group of cells in another part of the body.

1 department of physiology and biophysics medical science i d335 university of california irvine ca 92697 usa. Muscle is a remarkable living tissue it has the amazing potential to adapt to a presented stimulus or functional demand. In contrast satellite cells and myonuclei may undergo apoptosis during muscle atrophy although it is debated whether myonuclear loss occurs in atrophying muscle. The role of satellite cells in muscle hypertrophy has long been a debated issue.

Satellite cell proliferation and skeletal muscle hypertrophy. Specific to skeletal muscle hypertrophy hgf activates satellite cells and may be responsible for causing satellite cells to migrate to the injured area 2. This together with the observation that during various models of muscle hypertrophy there is an activation of the muscle stem cells i e. Hikida et al 2000.

In the late 1980s it was shown that proteins remain close to the myonucleus responsible for its synthesis giving rise to the idea of a nuclear domain. The myonuclear number did not change in any group. Following on from part 1 this article looks at the role of satellite cells in the muscle hypertrophy process. The role of satellite cells in muscle hypertrophy has long been a debated issue.

There was no change in satellite cells or mnd in the traditional endurance and control groups. These data are consistent with the hypothesis that testosterone administration induces skeletal muscle hypertrophy by promoting satellite cell replication and activation resulting in an increased number of myogenically committed satellite cells 23 34 36. Through the stimulus overload adaptation cycle muscle tissue has the ability to produce more contractile force store higher levels of substrate improve. A similar process is induced in adult skeletal muscle by functional overload and exercise.