Tiny hair cells called stereocilia have a role, in our ability to hear. These delicate structures, located in the ear are responsible for detecting waves. However factors like disorders exposure to noises and the natural aging process can lead to damage in these hair cells resulting in hearing difficulties and even deafness.
A team of researchers from the Salk Institute and the University of Sheffield has conducted promising experiments on mice making progress in research. Their groundbreaking work focuses on identifying a protein that can stimulate hair cell growth and potentially restore hearing function when delivered through gene therapy.
Dr. Uri Manor, a research professor and director of the Waitt Advanced Biophotonics Core at Salk shared his insights on this discovery; “Our findings provide hope by showing that we can restore hair cell function in specific cases. As someone who was born with severe, to hearing loss I see this as an opportunity to offer people a chance to regain their sense of hearing.”
Genetic factors are often attributed to childhood deafness especially when it occurs before children start speaking.
One genetic factor can lead to the underdevelopment of stereocilia which can result in deafness. These hair cells called stereocilia are spread throughout the cochlea a shaped structure found in the ear. Interestingly the length of these stereocilia varies in parts of the cochlea. The regions responsible, for detecting frequencies have stereocilia while those responsible for high frequencies have shorter ones.
The process of hearing begins when sound waves enter the ear and cause vibrations in the fluid inside the cochlea. This movement then causes the hair cells to move well. As these hair cells move they send signals to neurons that transmit information about the sounds we hear to our brain.
Previous research conducted by Dr. Uri Manor revealed a protein called EPS8 that plays a role in determining stereocilia length. Without EPS8 these hair cells fail to grow and end up with short stereocilia. Similarly Professor Walter Marcotti from the University of Sheffield had also previously identified a connection between EPS8 and stereocilia development.
In their study both researchers collaborated on an experiment aiming to investigate whether introducing EPS8 into stereocilia hair cells could stimulate their regrowth and potentially improve hearing, in mice.
They utilized an used technique, in gene therapy to transport the EPS8 protein into the hair cells by utilizing a virus. Afterward they assessed the impacts using imaging methods.
The outcomes were encouraging. The introduction of EPS8 resulted in an increase in the length of the stereocilia thereby restoring their functionality in cells to frequency sounds. Although this intervention didn’t completely restore the hearing abilities of the mice it represented an advancement in endeavors to restore hearing through gene therapy.
However the research did uncover an aspect related to these cells aging process. As the cells aged they seemed to lose their ability to regenerate suggesting that time might play a role in determining the success of treatments.
Dr. Uri Manor remains positive about what their discoveries can achieve; “EPS8 is a protein with multifaceted functions. There is still much we need to uncover about it. I am dedicated to furthering our research into hearing loss and firmly believe that our work holds promise for developing gene therapies that can effectively restore hearing.”
The teams forthcoming efforts will concentrate on deepening our understanding of how EPS8 works and investigating approaches to expand its effectiveness, over an age range.
The main objective is to offer people with hearing difficulties the chance to re engage with the world of sound. This groundbreaking study takes us a step nearer, to realizing that goal.