Stanford researchers published a paper today in Science Translational Medicine describing how stem cells are involved in the development of Duchenne muscular dystrophy, a disease that results in progressive, often severe muscle weakness. It affects about one in every 3,600 boys born in the U.S.
The research team determined that the stem cells surrounding muscle tissue gradually became less able to create new muscle cells and instead begin to express genes that lead to connective tissue formation. Excess connective tissue accumulation, which is called fibrosis, occurs in many diseases. Thomas Rando, MD, PhD, a Stanford neurologist and one of the authors of the paper said in a release about the new study:
These cells are losing their ability to produce muscle, and are beginning to look more like fibroblasts, which secrete connective tissue. It’s possible that if we could prevent this transition in the muscle stem cells, we could slow or ameliorate the fibrosis seen in muscular dystrophy in humans.
The researchers also found that a drug already approved to treat high blood pressure in humans called losartin can slow these changes in stem cells in laboratory mice, although much more work is needed to find out if it could be helpful in children with Duchenne.
The researchers are focusing on how to get the drug to target only muscle cells, but they’re also interested in how they can apply their findings to other diseases. Rando, who directs the Glenn Center for the Biology of Aging at Stanford, also commented:
Fibrosis seems to occur in a vicious cycle. As the muscle stem cells become less able to regenerate new muscle, the tissue is less able to repair itself after damage. This leads to fibrosis, which then further impairs muscle formation. Understanding the biological basis of fibrosis could have a profound effect on many other diseases.
Previously: Working on a gene therapy for muscular dystrophy, New mouse model of muscular dystrophy provides clues to cardiac failure, and Mouse model of muscular dystrophy points finger at stem cells
Photo of muscle cells affected by Duchenne disease by Edwin P. Ewing
