Protein Offers Hope in Fight on Dystrophy

Scientists say they have discovered how certain muscles in mice resist the most common and severe form of muscular dystrophy, a finding that may lead to a new approach in treating people.

The mouse muscles make up for the absence of a crucial protein called dystrophin by using a related protein called utrophin instead, the study suggests.

Human muscles also contain utrophin, and if they could be encouraged to make more of it they might also be able to fend off Duchenne muscular dystrophy, which afflicts about 15,000 Americans, the researchers said.

The work is presented in today’s issue of the journal Nature by Kevin Campbell, a Howard Hughes Medical Institute investigator and physiology professor at the University of Iowa College of Medicine, and his colleagues. An accompanying study shows that human utrophin is very similar to dystrophin.

“I think it opens up another avenue of treating Duchenne muscular dystrophy,” said Dr. Jon Wolff of the University of Wisconsin in Madison. “It’s a good idea . . . if you can figure out how to do it. And I’m sure somebody will do it.”

Dr. Lewis Rowland of the Columbia-Presbyterian Medical Center in New York cautioned that while such a therapy might help, “we’re a long way away from it.”

Duchenne muscular dystrophy strikes boys almost exclusively, usually ages 3 to 5. Muscles waste away and become progressively weaker, forcing most patients to use wheelchairs by the age of 12. Few patients survive beyond their mid-20s.

Duchenne is caused by a lack of dystrophin in the muscles. Dystrophin appears to act as an anchor for a complex of proteins, called dystrophin-associated proteins, which attach muscle cells to connective tissue. If dystrophin is not present, the dystrophin-associated proteins are lost and muscles are destroyed.