Résumé :
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Oxygen has been demonstrated to influence proliferation and myotubes differentiation. However, the mechanism of influence is mostly unknown. We have recently reported that satellite cells may be comprised of two distinct populations of cells distinguishable for proliferation and differentiation characteristics.Herewith, we studied cloned and un-cloned murine satellite cells under different oxygen conditions. In particular, we examined the growth, differentiation and myogenic genes expression during hypoxia (2% oxygen) and normoxia (20% oxygen) at 5, 10 and 15 days. We demonstrate that despite the same proportion and proliferation rate of clones were maintained when mouse satellite cells were cultured at both 2% and 20% O2, un-cloned satellite cells proliferation was significantly influenced by oxygen with the growth rate increasing at each time point at the lowest concentration. These data suggest that oxygen tension does not have any influence in both proliferation/differentiation processes in cloned populations. Taken together these results suggest that oxygen concentration may act on a specific subpopulation of satellite cells, which may exert influence on a different one modifying ultimately their proliferation rate.
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