Hair cells, which detect sound waves, are the primary cause of hearing loss and cannot regenerate if damaged or lost. This type of hearing loss is most common in people who are repeatedly exposed to loud noises, such as military personnel, construction workers, and musicians. However, birds and fish have the ability to regenerate hair cells. Researchers at the Del Monte Institute for Neuroscience are making progress in identifying the mechanisms that may promote hair cell regeneration in mammals.

The recent study published in Frontiers in Cellular Neuroscience found that activating the growth gene ERBB2 pathway triggers a series of cellular events that lead to the growth of new hair cells in mammals. Using single-cell RNA sequencing in mice, researchers compared cells with overactive growth genes to those that lacked such signaling. They found that the growth gene ERBB2 promoted stem cell-like development by initiating the expression of multiple proteins, including SPP1, a protein that signals through the CD44 receptor. This increase in cellular response promoted mitosis in supporting cells, which is a key event for regeneration.

According to Patricia White, PhD, professor of Neuroscience and Otolaryngology at the University of Rochester Medical Center:

“This discovery has made it clear that regeneration is not only restricted to the early stages of development. We believe we can use these findings to drive regeneration in adults. We plan to further investigation of this phenomenon from a mechanistic perspective to determine whether it can improve auditory function after damage in mammals. That is the ultimate goal.”

Check out the video below which illustrates how sound travels from the ears to the brain.