Effect of Simulated microgravity condition on cells proliferation and myostatin gene expression in differentiated skeletal muscle cells (C2C12)

Muscle atrophy is one of the problems that astronauts face after returning to earth. Myostatin is a known negative regulator of muscle growth. This study aimed to investigate the effects of simulated microgravity condition on mouse myotube cells (C2C12) growth and the myostatin gene expression. The morphological studies and MTT cytotoxicity assay showed no significant alternation in cells after 48h simulation microgravity, however, after 72h ~40% of cell death accrued (p<0.05). The AO/PI staining and DNA fragmentation analysis confirmed this observation too. Analysis of the gene expression revealed that simulated microgravity reduced myostatin gene expression significantly after 48h (p<0.0001), however, after 72h, increased significantly (P<0.001). So, inhibition of myostatin expression in differentiated myocyte cells of astronauts could be an effective procedure to reduce skeletal muscle atrophy under microgravity condition.