Researchers gain insight into protective mechanisms for hearing loss

September 17, 2013, Massachusetts Eye and Ear Infirmary

Researchers from the Eaton-Peabody Laboratories of the Massachusetts Eye and Ear and Harvard Medical School have created a new mouse model in which by expressing a gene in the inner ear hair cells—the sensory cells that detect sound and sense balance—protects the mice from age-related hearing loss (ARHL) and noise-induced hearing loss (NIHL), the two most common forms of deafness.

Their research, described in the Journal of Neuroscience, provides new insight into protective mechanisms for hearing loss and suggests the potential for future molecular approaches, which may include gene therapy or medicine, to treat ARHL and NIHL.

Hearing loss is a serious public health issue. Nearly one-third of adults 64 and older have significant ARHL. After age 85, that number almost doubles to 64 percent. NIHL, also a common complaint, is one of the most self-reported occupational injuries. The irreversible loss of inner ear outer cells is a cause of both types of hearing loss. Hearing aids and cochlear implants help those suffering from hearing loss in some cases, but there is no device that works for everyone and no cure.

Mass. Eye and Ear researchers set out to understand if both types of hearing loss share a common underlying mechanism by studying certain inbred strain of mice. They investigated whether overexpression of Isl1, an inner ear progenitor gene with roles in development and differentiation, could be effective in protecting the inner ear.

The team found that Isl1 expression protected hair cells from degeneration in aging and promoted hair cell survival after exposure to loud noise. As a result, the hearing in aged mice or in mice exposed to intense noise was significantly better than their siblings without the gene.

"The Isl1 gene further preserved the connections between hair cells and neurons, which is necessary for hearing," said senior author Zheng-Yi Chen, D.Phil., Mass. Eye and Ear researcher and Associate Professor of Otolaryngology, Harvard Medical School.

Future research can evaluate if Isl1 is protective from ARHL and NIHL in other mouse strains. The investigators hope to eventually study if such protection can be extended to the human condition.

"To our knowledge, our model is the first in which expression of a single gene in postnatal hair cells results in hair cell survival and hearing preservation in mice that otherwise suffer from age-related and noise-induced hearing loss," Dr. Chen said.

Explore further: Sensory hair cells regenerated, hearing restored in mammal ear

Related Stories

Sensory hair cells regenerated, hearing restored in mammal ear

January 9, 2013
Hearing loss is a significant public health problem affecting close to 50 million people in the United States alone. Sensorineural hearing loss is the most common form and is caused by the loss of sensory hair cells in the ...

Hearing loss clue uncovered

June 11, 2013
(Medical Xpress)—Researchers from the Department of Otolaryngology at the University of Melbourne and the Department of Biochemistry and Molecular Biology at Monash University have discovered how hearing loss in humans ...

Gene therapy holds promise for reversing congenital hearing loss

July 25, 2012
A new gene therapy approach can reverse hearing loss caused by a genetic defect in a mouse model of congenital deafness, according to a preclinical study published by Cell Press in the July 26 issue of the journal Neuron. ...

Study shows fruit fly is ideal model to study hearing loss in people

September 2, 2013
If your attendance at too many rock concerts has impaired your hearing, listen up.

Now hear this: Scientists discover compound to prevent noise-related hearing loss

August 29, 2013
Your mother was right when she warned you that loud music could damage your hearing, but now scientists have discovered exactly what gets damaged and how. In a research report published in the September 2013 issue of The ...

Hearing loss from loud blasts may be treatable, researchers say

July 1, 2013
Long-term hearing loss from loud explosions, such as blasts from roadside bombs, may not be as irreversible as previously thought, according to a new study by researchers at the Stanford University School of Medicine.

Recommended for you

MRI technique detects spinal cord changes in MS patients

April 20, 2018
A Vanderbilt University Medical Center-led research team has shown that magnetic resonance imaging (MRI) can detect changes in resting-state spinal cord function in patients with multiple sclerosis (MS).

Signaling between neuron types found to instigate morphological changes during early neocortex development

April 20, 2018
A team of researchers from several institutions in Japan has found that developing neocortex neurons in mammals undergo a morphological transition from a multipolar shape to a bipolar shape due at least partially to signaling ...

Gene variant increases empathy-driven fear in mice

April 20, 2018
Researchers at the Center for Cognition and Sociality, within the Institute for Basic Science (IBS), have just published as study in Neuron reporting a genetic variant that controls and increases empathy-driven fear in mice. ...

Scientists identify connection between dopamine and behavior related to pain and fear

April 19, 2018
Scientists at the University of Maryland School of Medicine have for the first time found direct causal links between the neurotransmitter dopamine and avoidance—behavior related to pain and fear.

Neurons derived from super-obese people respond differently to appetite hormones

April 19, 2018
US scientists have successfully generated hypothalamic-like neurons from human induced pluripotent stem cells (hiPSCs) taken from the blood and skin cells of super-obese individuals and people with a normal body weight. The ...

Pathways to spatial recognition

April 19, 2018
When you are lost or disoriented, your brain uses cues from your surroundings—landmarks both near and far—to sort out where you are. The information gathered by your senses is transmitted by nerve cells, or neurons, to ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.