Exposure to loud noises and aging can damage the delicate hair cells within the inner ear. Once damaged, these hair cells cannot heal or regrow, leading to permanent hearing loss. New research out of the University of Maryland School of Medicine reveals the important role a specific protein plays in the development of these hair cells, paving the way for additional research.
Importance of Inner Ear Hair Cells
The process of hearing is simple. Soundwaves are collected by the outer ear and pass through the bones in the middle ear until they reach the inner ear. Once there, some of the hair cells amplify the sounds while others transform the soundwaves into electrical signals that are then sent via the auditory nerve to the brain to be interpreted as sound.
These specialized hair cells are crucial to the hearing process. When they do not work properly or are damaged, hearing loss occurs.
Hair Cell Protein Research
Ronna Hertzano, MD, PhD, associate professor in the Department of Otorhinolaryngology Head and Neck Surgery at UMSOM, and Maggie Matern, PhD, a postdoctoral fellow at Stanford University, worked together in this study published in the journal Development.
Dr. Hertzano and her team were interested in looking at the role of the GFI1 protein. While completing her dissertation, she discovered that hearing loss was the result of a mutation in another protein, which appeared to be the result of a loss of GFI1 in the hair cells.
They studied gene expression in the hair cells of newborn mice who were genetically modified to not produce the GFI1 protein. They found that when that protein was absent, the embryonic hair cells were unable to develop into fully functional adult hair cells.
“Our findings explain why GFI1 is critical to enable embryonic cells to progress into functioning adult hair cells,” said Dr. Hertzano. “These data also explain the importance of GFI1 in experimental protocols to regenerate hair cells from stem cells. These regenerative methods have the potential of being used for patients who have experienced hearing loss due to age or environmental factors like exposure to loud noise.”
The results of this research are only the beginning. “Hearing research has been going through a Renaissance period, not only from advances in genomics and methodology, but also thanks to its uniquely collaborative nature among researchers,” said Dr. Herzano.
To learn more about hearing loss or to schedule an appointment with an experienced audiologist, contact San Francisco Audiology today.