Drug May Help Treat Muscular Dystrophy

Baltimore researchers have found that an old, cheap, widely prescribed blood-pressure medication helps stop muscle wasting in muscular dystrophy.

Johns Hopkins researchers say the blood-pressure medication losartan, or Cozaar, stops muscle wasting in mice carrying the genetic mutation for the most common, or Duchenne form, of muscular dystrophy.

After treating the mice for six months the scientists tested the animals’ muscle strength by giving them objects to hold onto. Treatment with losartan successfully led to significantly increased strength and decreased muscle fatigue when compared to untreated littermates.

The researchers have shown that muscle destruction seen in Duchenne muscular dystrophy and Marfan syndrome is due to stem cells in the muscle being unable to repair damaged muscle cells. These stem cells are unable to repair muscle damage because floating around the body there is too much of a certain protein, known as TGF-beta, or transforming growth factor beta.

This really is the first evidence that disrupting TGF signaling in cases of failed muscle regeneration can improve muscle repair, says Dr. Ronald Cohn of the McKusick-Nathans Institute for Genetic Medicine at Hopkins. We’re excited that targeting the TGF-beta pathway may lead to new therapies for treating muscle-wasting diseases and give affected kids new hope.