High frequency vibration (HFV) induces muscle hypertrophy in newborn mice and enhances primary myoblasts fusion in satellite cells

Abstract

The present study aimed at verifying "in vivo" and "in vitro" the effects of mechanical vibrations on muscle development and on differentiation of satellite cells, the "stem cells" of muscle tissue. We realized a bioreactor composed by an eccentric motor which produces a displacement of 11 mm at frequencies between 1 and 120 Hz on a plate connected to the motor. On the plate we fixed a cage used for animals and the dishes for satellite cells and linear acceleration provoked by the motor to samples was measured. We used 30 Hz as stimulating frequency and we treated newborn mice from their birth for the next four weeks one 1h/day and satellite cells 1 and 4 days 1h/day always at 30 Hz. Every week we collected from a control and a treated mouse tibialis anterior muscles and we performed Western Blot analysis and quantitative Real-Time PCR (qRT-PCR) to investigate proteins and genes involved in hypertrophy and atrophy pathways of skeletal muscle. On satellite cells we studied some genes involved in differentiation and fusion of primary myoblasts. Results demonstrate that mechanical vibration induces muscle hypertrophy within the first week of treatment and enhances terminal differentiation of myoblasts of treated satellite cells respect to control ones. © 2010 International Federation for Medical and Biological Engineering.