Molecular Basis of Skeletal Muscle Regeneration

Skeletal muscle regeneration is a vital process with important implications for various muscle myopathies and adaptations to physiological overload. Few of the molecular regulatory proteins controlling this process have so far been identified. Several growth factors have defined effects on myogenic precursor cells and appear to also be involved during regeneration. In addition, factors that may be released by cells of the immune system may activate satellite cells during regeneration. Many of these growth factors are associated with signalling cascades which transmit information to the nucleus. The nuclear "receptors" that receive the incoming signals are transcription factors that interact with DNA regulatory sequences in order to modulate gene expression. Of the nuclear factors isolated so far, the immediate-early genes are associated with muscle precursor cell proliferation. This review aims to synthesize the extensive research on myogenic differentiation and relate this to research concerning the molecular regulation of skeletal muscle regeneration. Key words: satellite cells, growth factors, signal transduction, transcription factors, gene regulation, overload adaptation