- Harvard scientists may have found a ‘cure’ for certain types of deafness by directly regenerating hair cells in the inner ear
- For this they have developed a “cocktail” of molecules capable of activating genes involved in the development of hair cells in mammals.
- This discovery could deliver a revolutionary approach to restoring hearing in people with the most common forms of deafness
A group of researchers from Harvard Medical School claim to have managed to restore hearing in mice by “reprogramming” the hair cells in their ears. Different types of deafness or hearing impairment affect 466 million people worldwide, including 34 million children.
In France, according to Inserm, 6% of 15-24 year olds, and more than 65% of people aged 65 and over are affected. All progress in the field is a hope for many people: hearing is indeed a capital that deteriorates over time. Exposure to loud sounds, aging or certain illnesses can tear off the cilia attached to these cells in varying proportions – these cilia never regenerate in mammals.
Scientists succeeded in regenerating hair cells in the ears of mice
Hair cells are found in the colchea, an organ behind the eardrum that is fluid-filled and coiled up – and are connected by nerves to the brain. They are the ones that transmit sounds of different frequencies to a cell that transforms them into electrical signals.
In their scientific paper published in Processdigns of the National Academy of Science, the researchers show that it is therefore possible by activating certain genes in mice to cause the regrowth of these eyelashes. Enough to imagine, if indeed it is possible to reproduce the feat in humans, a truly revolutionary approach to fight against deafness.
However, there is still an obstacle. The human being remains a little more complex to manipulate genetically. The approach uses a technique called siRNA. A kind of vector of a genetic message that can enter cells, delete bits of messenger RNA sequences to better recode them.
The field is still the subject of intense research in humans, although with a much lower degree of effectiveness. One of the problems to be solved with the siRNA technique is the precise targeting of the cells to be temporarily reprogrammed to deliver a treatment.
It will therefore probably take several more years to hope for the first clinical tests. Other fairly effective treatments already exist to restore hearing in some patients. The latter may require the placement of an auditory implant directly in the colchea.
But the advantage of such an approach would be to be able to directly generate an affected ear, without risking any surgery. Hope for many sufferers. To protect your hearing capital, remember to avoid listening to sounds that are too loud for a long time – and in case of exposure to such conditions, wear appropriate protection such as earplugs or special protective helmets.
