DEFICIENCY, ALTERED CELL SIGNALING AND FIBER HYPERTROPHY

Dystrophin is a subsarcolemmal protein which is defective in Duchenne and Becker muscular dystrophy (DMD/BMD), and in three animal models. C linical manifestations of dystrophin deficiency in humans range from a mild calf muscle hypertrophy with cramps to the classical progressive degenerative hypertrophic myopathy of Duchenne. A common feature in t he clinical presentation of dystrophin deficiency in humans and in the three documented animal models is the presence of muscle fibre hypert rophy. This paper explores the hypothesis that membrane-bound signalli ng processes are disrupted in the absence of dystrophin, and suggests that these abnormalities may contribute to both the hypertrophic and d egenerative changes of dystrophin deficiency.