Dystrophin expression improves myofiber survival in mdx muscle following intramuscular plasmid DNA injection

Expression of Becker-like and full-length human dystrophins was stable for at least 6 months in mdx mouse muscle following intramuscular plasmid DNA injection. Intramuscular injection of a single plasmid DNA encoding both luciferase and dystrophin resulted in stable luciferase expression for at least 2 months in mdx muscle, whereas injection of plasmid DNA encoding only luciferase did not result in stable luciferase expression. These results suggest that expression of either full-length or Becker-like dystrophins protects mdx mouse myofibers from degeneration.