"some myokines exert their effects within the muscle itself. thus, myostatin, lif, il-6 and il-7 are involved in muscle hypertrophy and myogenesis, whereas bdnf and il-6 are involved in ampk-mediated fat oxidation. il-6 also appears to have systemic effects on the liver, adipose tissue and the immune system, and mediates crosstalk between intestinal l cells and pancreatic islets. other myokines include the osteogenic factors igf-1 and fgf-2; fstl-1, which improves the endothelial function of the vascular system; and the pgc-1alpha-dependent myokine irisin, which drives brown fat-like development. studies in the past few years suggest the existence of yet unidentified factors, secreted from muscle cells, which may influence cancer cell growth and pancreas function. many proteins produced by skeletal muscle are dependent upon contraction; therefore, physical inactivity probably leads to an altered myokine response, which could provide a potential mechanism for the association between sedentary behaviour and many chronic diseases."