Gene identified that may recover hearing loss

April 25 (UPI) -- Researchers at the University of Rochester Medical Center have discovered a protein that may play a role in restoring hearing after damage from noise exposure.

Hearing loss affects approximately one-third of people at retirement age and the problem is more severe in members of the military with nearly 60 percent of military members who were deployed to war experiencing hearing loss.

The gene known as the Forkhead Box O3, or Foxo3, which has been found to impact human longevity, protects the outer hair cells in the inner ear from damage. Foxo3 is known to play an important role in the stress response of cells, such as helping heart cells stay healthy by clearing away debris when the cells are damaged.

People with a genetic mutation that results in higher levels of Foxo3 have been shown to live longer.

"While more than a hundred genes have been identified as being involved in childhood hearing loss, little is known about the genes that regulate hearing recovery after noise exposure," Dr. Patricia White, a research associate professor in the University of Rochester Medical Center's Department of Neuroscience, said in a press release.

"Our study shows that Foxo3 could play an important role in determining which individuals might be more susceptible to noise-induced hearing loss."

Researchers conducted a series of experiments that involved knock-out mice who were genetically-engineered to lack the Foxo3 gene and found, compared to control mice, they were unable to recover hearing after being exposed to loud noises.

The Foxo3 knock-out mice also had lost most of their outer hair cells compared to control mice who did not lose a significant amount of hair cells.

"Discovering that Foxo3 was important for the survival of outer hair cells is a significant advance," White said. "We are also excited about the results because Foxo3 is a transcription factor, which regulates the expression of many target genes. We are currently investigating what its targets might be in the inner ear, and how they could act to protect the ear from damage."

The study was published in Scientific Reports.