Duchenne muscular dystrophy (DMD) is a recessive X-linked form of
muscular dystrophy characterized by progressive muscle degeneration. This disease is caused by the mutation or deletion of the
dystrophin gene. Currently, there are no effective treatments and
glucocorticoid administration is a standard care for DMD. However, the mechanism underlying
prednisolone effects, which leads to increased walking, as well as decreased muscle wastage, is poorly understood. Our purpose in this study is to investigate the mechanisms of the efficacy of
prednisolone for this disease. We converted fibroblasts of normal human cell line and a DMD patient sample to myotubes by MyoD transduction using a retroviral vector. In myotubes from the MyoD-transduced fibroblasts of the DMD patient, the myotube area was decreased and its apoptosis was increased. Furthermore, we confirmed that
prednisolone could rescue these pathologies.
Prednisolone increased the expression of not
utrophin but
laminin by down-regulation of MMP-2
mRNA. These results suggest that the up-regulation of
laminin may be one of the mechanisms of the efficacy of
prednisolone for DMD.