Insulin-like growth factor 1 and the key markers of proteolysis during the acute period of reloading of the muscle atrophied under disuse
ABSTRACT It has been shown that, after prolonged disuse, the accumulation of muscle mass and the recovery of soleus fiber volume are
caused by water accumulation rather than protein synthesis intensification. At the same time, the expression rate of the main
markers of the activity of ubiquitin-proteasome system remained increased on the 3rd day of reloading and decreased to the
control by the 7th day. Both the quantity of the insulin-like growth factor 1 and the number of satellite cells fused with
muscle fibers and of myonuclei began to increase only on the 7th day of reloading. The data obtained evidenced a significant
inertness of the postural muscle during its adaptation to the load (normal gravity) after prolonged disuse.
Keywordsskeletal muscle–atrophy–reloading–proteolysis–signaling systems