Did you know that more people have hearing loss than diabetes, cancer or vision trouble? According to the Centers for Disease Control and Prevention, occupational hearing loss, which is caused by exposure at work to loud noise or chemicals that damage hearing, is the most common work-related illness.

New therapy for hearing loss

Wearing the proper PPE and taking precautions around heavy machinery, loud noises and even household noise such as the lawn mower can prevent hearing loss, but once noise-induced hearing loss begins, it is permanent and irreversible.2 There is hope, however. New treatment methods and technologies are being developed to help those with irreversible hearing damage. 

A study just released in October 2018 reveals that researchers at the University of Rochester Medical Center have taken an important step toward what may become a new approach to restore hearing loss.3 In the study, scientists have been able to regrow the sensory hair cells found in the cochlea, a part of the inner ear that converts sound vibrations into electrical signals and can be permanently lost due to age or noise damage.

Hearing impairment has long been accepted as a fact of life for many. An estimated 30 million Americans suffer from some degree of hearing loss. However, scientists have long observed that other animals have been shown to have the ability to regenerate lost sensory hair cells, says the study published in the European Journal of Neuroscience.

Researcher discovers cell connection

Research conducted in the lab of Patricia White, Ph.D., in 2012 identified a family of receptors called epidermal growth factor (EGF) responsible for activating support cells in the auditory organs of birds. When triggered, these cells proliferate and foster the generation of new sensory hair cells. She speculated that this signaling pathway could be manipulated to produce a similar result in mammals. White is a research associate professor in the University of Rochester Medical Center (URMC) Del Monte Institute for Neuroscience and lead author of the study.

In the study, the team tested the theory that signaling from the EGF family of receptors could play a role in cochlear regeneration in mammals. The researchers focused on a specific receptor called ERBB2, which is found in cochlear support cells.

The researchers found that activating the ERBB2 pathway triggered a cascading series of cellular events by which cochlear support cells began to proliferate and start the process of activating other neighboring stem cells to become new sensory hair cells. They discovered that this process not only could impact the regeneration of sensory hair cells, but also support their integration with nerve cells.4

“The process of repairing hearing is a complex problem and requires a series of cellular events,” said White. “You have to regenerate sensory hair cells and these cells have to function properly and connect with the necessary network of neurons. This research demonstrates a signaling pathway that can be activated by different methods and could represent a new approach to cochlear regeneration and, ultimately, restoration of hearing.”


Sources:

  1. https://blogs.cdc.gov/niosh-science-blog/2016/04/27/hearing-loss-years-lost/
  2. https://blogs.cdc.gov/niosh-science-blog/2016/02/08/noise/
  3. https://www.sciencedaily.com/releases/2018/10/181015132953.htm
  4. https://www.urmc.rochester