New Therapeutic Insight Into Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy, affecting about 1 in 3000 males each year. It is an X-linked recessive disease, in which mutations in the dystrophin gene causes progressive and degenerative muscle weakness. DMD is generally lethal by age 30.

Dr. Spiegelman and colleagues found that a protein called PGC-1alpha regulates the point of connection between the end of a motor neuron and a muscle fiber -- what researchers call the "neuromuscular junction." Electrical impulses travel through the neuromuscular junction, ultimately causing the muscle to contract. Previous research has shown that PGC-1alpha expression is induced by physical exercise and motor neuron activity, and mediates the anti-atrophic effects of nerve activity on muscle mass.

Dr. Spiegelman and colleagues analyzed the function of PGC-1alpha in a mouse model of DMD. They found that PGC-1alpha activates the expression of several genes that are aberrantly inactivated in DMD. In fact, by inducing PGC-1alpha expression in these transgenic mice, the scientists were able to improve DMD symptoms.

"These data clearly show that experimental elevation of PGC-1 alpha has therapeutic promise in an animal model of Duchene's muscular dystrophy. We hope this will lead eventually to therapeutics for a terrible disease for which there is no effective treatment at the present time," explains Dr. Spiegelman.