Our Goal Is to Translate Regeneration to Humans
The Hearing Restoration Project (HRP) is funding research to translate what we know about chickens and other animals to people, leading to a cure for hearing loss. With 90% of tinnitus (ringing in the ears) occurring with an underlying hearing loss, a cure for hearing loss may also be a cure for tinnitus. Read more about our path to a cure for hearing loss and tinnitus.
The Amazing Chicken Discovery: An Accident?
Similar to other important scientific discoveries such as penicillin, the discovery that chickens can regenerate their own hearing occurred almost by accident. While studying how drugs that are known to cause hearing damage affect the tiny sensory cells in the ear, HHF-funded scientists needed to permanently damage a chicken’s hair cells.
In this study, research assistants administered a common antibiotic for 10 days, known to cause hearing loss, to laboratory chickens. On day 11 many of the hair cells were lost and a few days later, even more were lost. Surprisingly, when the scientists looked three weeks later, almost all the hair cells had returned. They didn’t believe these results so they did the experiment again and again. Sure enough, chickens can naturally regenerate their inner ear hair cells, restoring their hearing after damage. Now we know this ability is true of all vertebrate animals except one, mammals, including humans.
We Have Seen Early Success in Mice
Regenerating inner ear hair cells has already proven successful with mice. A recent discovery by one of our HRP scientists revealed that mice can be stimulated to regenerate hair cells and partially restore hearing. This was done by using a drug to block a certain auditory pathway that prevents hair cell regeneration in mammals. Once blocked, the supporting cells in the cochlea were free to transform into hair cells, partially restoring hearing. While much work remains, this proof of concept indicates that hair cell regeneration can be made to occur in mammals.