The relationship of the signaling via eATP with the regulation of FGF21 is also supported by reports of direct effects of FGF21 on skeletal muscle (glucose uptake (37), formation of aerobic fibers (41), control of muscle mass (12) and its alterations in pathological conditions such as Duchenne muscular dystrophy (40)), situations in which our laboratory has reported that signaling mediated by eATP participates directly, or is altered (47, 50, 54). Here, FGF21 is linked to Duchenne muscular dystrophy.