Mechanisms of anabolic steroid action in bovine skeletal muscle

It is well established that anabolic steroids provide a significant economic benefit by enhancing both rate and efficiency of muscle growth in cattle; and, thus, these compound are widely used as growth promoters in the beef cattle industry. However, the mechanisms by which anabolic steroids enhance bovine muscle growth remain unclear. Questions remain as to the relative importance of genomic versus non-genomic effects of steroids on muscle growth. The relative importance of increased satellite cell numbers, increased circulating IGF1 and increased production of IGF1 in muscle tissue also remains unclear. Additionally, the involvement of specific growth factor receptors and of various intracellular signaling pathways and of cross-talk between various receptors and pathways in anabolic steroid-enhanced muscle growth needs to be delineated. In summary, it is clear that anabolic steroid-enhanced bovine muscle growth involves a complex interaction of numerous pathways and receptors. Continued research is necessary to understand mechanism involved in this complex process. In the future, the fundamental information generated by this research will help in developing safe and effective strategies to increase rate and efficiency of muscle growth in beef cattle.