Researchers have taken an important step toward what may become a new approach to restore hearing loss. In a new study, out today in the European Journal of Neuroscience, 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 the aging population – an estimated 30 million Americans suffer from some degree of hearing loss. However, scientists have long observed that other animals – namely birds, frogs, and fish – have been shown to have the ability to regenerate lost sensory hair cells.
“It’s funny, but mammals are the oddballs in the animal kingdom when it comes to cochlear regeneration,” said Jingyuan Zhang, Ph.D., with the University of Rochester Medical Center (URMC) Department of Neuroscience and first author of the study. “We’re the only vertebrates that can’t do it.”
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 potentially be manipulated to produce a similar result in mammals. White is a research associate professor in the URMC Del Monte Institute for Neuroscience and lead author of the current study.
“In mice, the cochlea expresses EGF receptors throughout the animal’s life, but they apparently never drive regeneration of hair cells,” said White. “Perhaps during mammalian evolution, there have been changes in the expression of intracellular regulators of EGF receptor family signaling. Those regulators could have altered the outcome of signaling, blocking regeneration. Our research is focused on finding a way switch the pathway temporarily, in order to promote both regeneration of hair cells and their integration with nerve cells, both of which are critical for hearing.”
In the new study, which involved researchers from URMC and the Massachusetts Ear and Eye Infirmary, which is part of Harvard Medical School, 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 investigated a number of different methods to activate the EGF signaling pathway. One set of experiments involved using a virus to target ERBB2 receptors. Another, involved mice genetically modified to overexpress an activated ERBB2. A third experiment involved testing two drugs, originally developed to stimulate stem cell activity in the eyes and pancreas, that are known activate ERBB2 signaling.
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. Furthermore, it appears that this process not only could impact the regeneration of sensory hair cells, but also support their integration with nerve cells.
“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.”
The Latest on: Hearing restoration
via Google News
The Latest on: Hearing restoration
- Oticon More™ hearing aids now offer more sound, more music, more choice and freedomon October 14, 2021 at 7:19 am
Oticon has expanded the Oticon More™ hearing aid portfolio to now include, a groundbreaking music programme, a new miniRITE style, a new SmartCharger and a new rechargeable CROS transmitter to the ...
- Apple, Bose and others pump up volume on hearing aid options, filling void left by FDAon October 14, 2021 at 3:00 am
Spurred by decades of complaints about the high cost of hearing aids, Congress passed a law in 2017 to allow over-the-counter sales, with hopes it would boost competition and lower prices.
- OPINION: for a music lover, sudden hearing loss feels like thefton October 14, 2021 at 3:00 am
I read an advert recently with the words “Musicians have been silenced for 12 months. We *will* enjoy their music together again” in the headline.
- ASL is not just for the hearing-impaired — experience a range of ASL courses for under $30on October 14, 2021 at 1:00 am
Sponsored Deals While undoubtedly the mainstay of the deaf community, the benefits of learning ASL to those of us who not have suffered hearing loss are many.
- Why should you turn down the music? 17 percent of adults experience noise-induced hearing losson October 13, 2021 at 2:00 am
Noise-induced hearing loss is the second-most common form of hearing deficit after age-related hearing loss. But unlike the hearing loss that comes with age, the losses we suffer from exposure ...
- Urgent warning about Apple AirPods and other earphones ‘that trigger health issues like vertigo and hearing loss’on October 12, 2021 at 7:55 pm
OWNERS of in-ear headphones like Apple AirPods have been warned using them could cause serious health issues like vertigo and even hearing loss. Repeated and long-lasting use of the gadgets could ...
- What Is Noise-Induced Hearing Loss?on October 12, 2021 at 8:25 am
Noise-induced hearing loss affects roughly 17 percent of adults, and is the result of repeated or excessive exposure to loud noises. It’s not as much a matter of how loud a sound seems, but how ...
- Hearing Loss Linked to Multiple Health Problemson October 11, 2021 at 11:00 am
Most of us will lose some of our ability to hear as we age. But hearing loss may pose a previously overlooked risk, according to recently published research. Three separate studies found that those ...
- SENIOR SPOTLIGHT: The impacts of hearing losson October 8, 2021 at 9:00 pm
Did you know that hearing loss affects nearly 28 million Americans? It can begin gradually, with a buzzing in the ears or the sense that others are mumbling, or it ...
via Bing News