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Growth factors, muscle function and doping.

Departments of Surgery, Anatomy and Developmental Biology, Royal Free and University College Medical School, University of London, Rowland Hill Street, London NW3 2PF, UK.
Current Opinion in Pharmacology (Impact Factor: 5.44). 07/2008; 8(3):352-7. DOI: 10.1016/j.coph.2008.02.002
Source: PubMed

ABSTRACT Recently much interest has been shown in developing a treatment of muscle wasting associated with a range of diseases as well as in ageing, which are major medical and socioecomonic problems. Emerging molecular techniques have made it possible to gain a better understanding of the growth factor genes involved and how they are activated by physical activity including the IGF-I gene that can be spliced to give rise to different isoforms, one of which is called MGF that activates muscle progenitor cells that provide the extra nuclei required for muscle hypertrophy, repair and maintenance. This fact that MGF 'kick starts' the hypertrophy process clearly has potential for abuse and has already attracted the attention of body builders.

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