FIGURE 1.

Skeletal damage occurs during myopathies and in response to xenobiotics and exercise. Upon injury, circulating platelets are activated and clot to ensure the repair and integrity of the blood vessels adjacent to the necrotic myofibers. In addition to their role in hemostasis, platelets have signaling functions in muscle regeneration. Platelet-secreted chemokines are necessary for the recruitment of neutrophils to the damaged muscle [25], and this initial step of regeneration is followed by the subsequent infiltration of other immune cell populations into the injured muscle. In addition, platelet- and neutrophil-secreted growth factors (e.g., VEGF) contribute to other aspects of muscle regeneration, such as neo-angiogenesis and myofiber growth. Platelet-secreted factors collectively initiate muscle regeneration by recruiting neutrophils to the injured muscle, the growth of new myofibers and blood vessels (myogenesis and angiogenesis), and the optimal recovery of muscle force production post injury [25]. The scheme was drawn with BioRender.