Researchers at the Stanford University School of Medicine report that they have found a way to regenerate hair cells in the inner ears of mice, allowing the animals to recover vestibular function. Their study was published recently in Cell Reports.
Many people experience vestibular dysfunction, some because of problems with inner ear hair cells. They can feel as if they’re spinning, lose their balance easily, suffer from nausea, and have trouble tracking objects with their eyes.
There is currently no effective treatment for dizziness and balance disorders caused by damaged or lost vestibular hair cells. The only available therapy is teaching patients coping mechanisms through physical therapy, a media release from Stanford Medicine notes.
The hair cells in the utricle, a section of the inner ear, help maintain balance and spatial orientation and regulate eye movement. Some antibiotics can damage these cells. Damage can also occur from infections or genetic disorders, or as a result of aging. In mature mammals, vestibular hair cells regenerate on their own only minimally, the release explains.
In their study, researchers including Alan Cheng, MD, associate professor of otolaryngology-head and neck surgery at Stanford University and Zahra Sayyid, an MD-PhD student at Stanford, impaired the inner ear hair cells of mice and measured how well they regenerated on their own. The researchers found that about a third of the cells regenerated spontaneously but appeared immature, and vestibular function was inconsistent.
Next, they manipulated Atoh1, a transcription factor that regulates hair cell formation, in the mice. In the animals that overexpressed Atoh1, as much as 70% of hair cells regenerated. The regenerated cells appeared relatively mature, and about 70% of these mice recovered vestibular function, the release continues.
“This is very exciting. It’s an important first step to find treatment for vestibular disorders,” says Cheng, the study’s senior author. “We couldn’t get sufficient regeneration to recover function before.”
The researchers plan to study how other methods to enhance Atoh1’s function may affect regeneration.
While the finding is a proof of concept, “it has opened the door for many more possibilities that could lead to treatment in people with vestibular disorders,” adds Sayvid, the study’s lead author.
[Source: Stanford Medicine, News-Medical Life Sciences]