Muscle stem cells are activated by stress
Myoblasts are muscle stem cells that differentiate and fuse together to form mature skeletal muscle. These cells form the muscle fibers that allow us to move our body and do everyday tasks. The myoblasts also exist as satellite cells in mature muscle, and are activated for development or repair. Myoblasts are sensitive to their surrounding mechanical environment and are known to differentiate and organize into skeletal muscle on surfaces with elastic modulus E ~ 12 kPa.
In our study, we investigated how myoblasts responded to cyclic mechanical stretching, as would occur in our muscles during everyday movement. We found that myoblasts under shear strain showed signs of differentiation not usually observed on stiff surfaces. These results suggest the stress-strain state of the cell may be important in cell differentiation and organization.
W. Ahmed, T. Wolfram, A. Goldyn, K. Bruellhoff, B. Aragues Rioja, M. Moller, J. P. Spatz, T. A. Saif, J. Groll, R. Kemkemer. “Myoblast morphology and organization on biochemically micro-patterned hydrogel coatings under cyclic mechanical strain” Biomaterials, 31: 250-8. 2010 (DOI: 10.1016/j.biomaterials.2009.09.047) [link]