Alec Smith is the PI of a newly awarded NIH R21 grant to study muscle spindle dysfunction in Duchenne Muscular Dystrophy. David Mack, Mike Regnier, and Mark Bothwell are co-investigators.
Muscle spindles are sensory end organs in muscle that allow sensation of muscle position and movement. As muscle spindles are comprised of clusters of specialized types of muscle fibers, their proper function is likely dependent on dystrophin, just as the muscle proper is. Dystrophin mutations in Duchenne Muscular Dystrophy cause a loss of muscle cell dystrophin. Thus, it is plausible that DMD patients may experience muscle spindle dysfunction, which may contribute to the tendency of DMD patients to suffer frequent falls.
In order to develop an experimental system to study human muscle spindle function, Alec and team will produce muscle spindle cells in vitro, by differentiation of induced pluripotent stem cells bearing a dystrophin mutation, and from wild type control cells.