February 27, 2009

Scientists move closer to MD solution

A University of Missouri team of scientists identified the location of the genetic material vital to curing muscular dystrophy.

Dongsheng Duan said Duchenne muscular dystrophy, which predominantly affects males, is the most common type of muscular dystrophy. Patients with Duchenne muscular dystrophy have a gene mutation that disrupts the production of dystrophin. Absence of dystrophin starts a chain reaction that eventually leads to muscle cell degeneration and death.

A previous study by Duan discovered a potential delivery method to replace the mutated genes with healthy genes. Following the replacement of these genes, Duan observed that dystrophin production was restarted in animals with muscular dystrophy.

However, while dystrophin is vital for muscle development, the protein also needs several helpers to maintain the muscle tissue.

One of these helper molecular compounds is nNOS, which produces nitric oxide. This is important for muscles that are in used during high intensity movements, such as exercise.

In the study, scheduled to be published in The Journal of Clinical Investigation, the team identified the location of genetic material responsible for the production of nNOS.

In addition, after genetically correcting mice with the new dystrophin gene, the team discovered that the missing nNOS was then restored in the dystrophic muscle, so when the mice exercised they did not experience the muscle damage or fatigue.