Irvine, Calif. ? In separate studies released today, researchers have identified the potential for adult stem cells in the nervous system to regenerate and possibly repair damaged areas of the retina and brain.

Stem cells are “primitive” cells that scientists theoretically can manipulate to give rise to different cell types in the body. In addition to their role in development, stem cells are found in fully developed organisms, where they repair injuries to the skin, muscle or other body parts.

Anne Calof, professor of neurobiology at the University of California, Irvine, and graduate student Joon Kim have used genetic studies of mice to understand how stem cells are controlled in the retina, the part of the eye responsible for the sense of vision.

The researchers found that a protein called GDF11 plays an important role in inhibiting stem-cell development in the retina, thereby regulating the size of the optic nerve, which conducts visual signals from the eye to the brain.

The next step is determining whether drugs can interfere with GDF11 to permit the original stem cells to repair developmental disorders of the eye.

Such studies could lead to drug therapies for retinal disorders such as macular degeneration.

The studies appear in today’s issue of the journal Science.