Background: Myogenic progenitor cells (activated satellite cells) are able to express both
HGF and its receptor cMet. After muscle injury, HGF-Met stimulation promotes activation and primary
division of satellite cells. MAGIC-F1 (Met-Activating Genetically Improved Chimeric Factor-1) is an
engineered protein that contains two human Met-binding domains that promotes muscle hypertrophy.
MAGIC-F1 protects myogenic precursors against apoptosis and increases their fusion ability enhancing
muscle differentiation. Hemizygous and homozygous Magic-F1 transgenic mice displayed constitutive
Methods: Here we describe microarray analysis on Magic-F1 myogenic progenitor cells showing an altered
gene signatures on muscular hypertrophy and angiogenesis compared to wild-type cells. In addition,
we performed a functional analysis on Magic-F1+/+ transgenic mice versus controls using treadmill test.
Results: We demonstrated that Magic-F1+/+ mice display an increase in muscle mass and cross-sectional
area leading to an improvement in running performance. Moreover, the presence of MAGIC-F1 affected
positively the vascular network, increasing the vessel number in fast twitch fibers. Finally, the gene expression
profile analysis of Magic-F1+/+ satellite cells evidenced transcriptomic changes in genes involved
in the control of muscle growth, development and vascularisation.
Conclusion: We showed that MAGIC-F1-induced muscle hypertrophy affects positively vascular network,
increasing vessel number in fast twitch fibers. This was due to unique features of mammalian
skeletal muscle and its remarkable ability to adapt promptly to different physiological demands by modulating
the gene expression profile in myogenic progenitors.