Stem cells may help repair MD muscles

BOSTON, July 11 (UPI) -- Transplanted muscle stem cells can improve muscle function in animals with a form of muscular dystrophy, Boston researchers said.

Lead author Amy J. Wagers of Joslin Diabetes Center and Harvard University said Duchenne muscular dystrophy is the most common form of the disease and is characterized by rapidly progressing muscle degeneration.

The study, published in the journal Cell, demonstrated that regenerative muscle stem cells can be distinguished from other cells in the muscle by unique protein markers present on their surfaces. The authors used these markers to select stem cells from normal adult muscle and transferred the cells to diseased muscle of mice carrying a mutation in the same gene affected in human Duchenne muscular dystrophy.

"Once the healthy stem cells were transplanted into the muscles of the mice with muscular dystrophy, they generated cells that incorporated into the diseased muscle and substantially improved the ability of the treated muscles to contract," Wagers said in a statement.

"At the same time, the transplantation of the healthy stem cells replenished the formerly diseased stem cell pool, providing a reservoir of healthy stem cells that could be re-activated to repair the muscle again during a second injury."