A Better Understanding of Deafness

By Jane Farrell

Damage to cells that are crucial to hearing may not have to result in deafness. Instead, researchers have found, new hearing cells seem to take over the job.

In a paper published in the Proceedings of the National Academy of Sciences, researchers from the University of Michigan Medical School, St. Jude Children’s Research Hospital and colleagues reported on their in-depth studies of “supporting” cells.

The investigation showed that damage to the supporting cells in the ear of a mature mouse results in the loss of hair cells as well as profound deafness. But if supporting cells are lost in a newborn mouse, the ear rapidly regenerates new supporting cells. And that means hearing is completely preserved.

The scientists said that the regeneration stemmed from cells from a nearby structure moving in and transforming themselves into supporting cells.

Further research – i.e. an analysis of what’s happening inside the cells – may pave the way for new apprpoaches to regenerating auditory cells and restoring hearing in humans.

Gabriel Corfas, senior author and U-M Kresge Hearing Research Institute director, said the research shows there’s an intrinsic regenerative potential in the very early days of life that we could harness as we work to cure deafness. “This is relevant to many forms of inherited and congenital deafness, and hearing loss due to age and noise exposure,” he said.

“If we can identify the molecules that are responsible for this regeneration, we may be able to turn back the clock inside these ears and regenerate lost cells.”