The saying goes that we shouldn't let the perfect be the enemy of the good, so while there is no cure for muscular dystrophy, rather than solely focusing on the underlying genetic defect might not help people right now as directly targeting muscle repair.
Muscular dystrophies are a group of muscle diseases characterized by skeletal muscle wasting and weakness. Mutations in certain proteins, most commonly the protein dystrophin, cause muscular dystrophy in humans and also in mice.
A University of Michigan team led by cell biologist Haoxing Xu discovered that mice missing a critical calcium channel inside the cell, called TRPML1, showed similar muscle defects as those present in muscular dystrophy patients. Though these mice did not have the defect in dystrophin, they still developed muscular dystrophy-like muscle characteristics.
When researchers increased the activity of the calcium channel in the muscular dystrophic mice, it improved muscle membrane repair and restored muscle function.
"The hope is that the same calcium channel will work in people with muscular dystrophy," Xu said.
The long-term plan is to develop clinical trials of a drug that would provide the extra activity of TRPML1.
While the treatment in mice using a gene therapy approach involved a viral carrier to insert extra TRPML1 channels in muscle, Xu says his team has recently discovered a drug that can activate this calcium channel. This drug might provide a similar boost to muscle membrane repair in human muscular dystrophy patients, but this requires further test in the laboratory.