reverse hearing loss by regrowing hair cells

According to researchers, it is possible to reverse this process and restore hearing by stimulating the growth of hair cells in the inner ear. These specialized cells are responsible for hearing and allow us to hear. 

If the hair cells die from exposure to a bang or certain antibiotics or chemotherapy, they usually do not grow back. That’s why scientists have long been trying to find a way to regenerate them.

The idea is to inject a drug directly into the inner ear, which leads to specialized progenitor cells producing new hair cells directly in the cochlea.

Beating clinical trial results

The first clinical trials have already been conducted on patients injected into the inner ear with cells from which hair cells would develop. The study’s results are auspicious: most patients reported improvements in speech perception. 

In some patients, the improvement appeared after the first injection and lasted almost two years. In total, more than 200 patients were administered the drug in three clinical trials, and each time there was a marked improvement in speech perception.

The results of another clinical trial currently underway on 124 patients will be published in early 2023. It remains to keep our fingers crossed for its success.

It is worth noting here that we are dealing with so-called regenerative medicine, which focuses on repairing, restoring, and regenerating tissues and organs. In this case, hair cells to a state similar to that found in healthy people. As a result, if adequately treated, a person with hearing loss could again hear without needing any assistive devices such as hearing aids or cochlear implants. Since this could be a breakthrough and a revolution for hundreds of millions of people worldwide, it’s worth a try.

What is hereditary hearing loss? 

The inner ear’s sensory cells, also known as hair cells, convert sounds, and vibrations into electrical signals transmitted through nerves and interpreted in the brain. The ability to hear depends on the ability of protein cells to reach the outer membrane of sensory cells in the inner ear. 

In some cases of hereditary, mutations involving the protein prevents it from entering into these membranes, which can result in hearing loss. This is because the mutated form of the protein makes the hair cells in the ear unable to recognize and transfer the protein to the membranes necessary for hearing. 

By this, most of the mutant protein gets caught and held in the hair cells. Defective secretion of the clarin protein can occur in people with Usher syndrome. This rare condition (3.5-6.2 per 100,000 sufferers) results from a genetic mutation. It leads to gradual loss of hearing and vision.

Treatment success?

Both drugs enabled young individuals to release trapped proteins, making artemisinin more effective. Not only did the drug help mutant clarin-1 reach the membrane, but it also meant that hearing and balance functions were better preserved in striped danios treated with the antimalarial drug than in untreated fish.

Survival rates in the clarin-1 mutant-secreting striped danios increased from 5% to 45% after treatment with artemisinin. In this species, survival depends on normal swimming behavior, balance, and the ability to detect water movement. All of this is related to hair cell function.