Restoring Hearing Through Cell Reprogramming and Regeneration

Harvard scientists have developed a new hearing loss treatment that restores hearing through cell reprogramming and regeneration.

Recently, researchers at Harvard University have made another breakthrough in “restoring” sensorineural hearing loss. Through mouse models, the scientists have been working on hair cell regeneration through cell reprogramming. Hair cell regeneration research has been explored for over three decades; however, until recently, regeneration research focused on neonatal or embryonic animals’ inner ears. Although researchers hoped to look at adult animals, the approaches that worked very well in younger mice failed in older animals.

Several years ago, researchers identified two genes, Myc and Notch1. Chen et al (2023) reported that, by using a genetic animal model to turn on the genes with another chemical compound, reprogramming a fully mature, adult mouse inner ear was possible. By activating these, Chen and his group were able to support cell proliferation in animal models. These cells surround the inner ear hair cells.

Reprogramming turns the biological clock backward, so, even in the fully mature animal, by turning on Myc and Notch1, those hair cells are made young again. The cocktail is delivered using a needle inserted into the eardrum to deliver the mixture into the middle ear. The mixture then migrates into the inner ear.

Hearing loss affects a significant portion of the population. As Dr. Chen reports “I think we are really at a turning point where we’ll see a new revolutionary novel treatment come on board from gene therapy to regeneration. This has the potential to transform not only our field of hearing loss but also could have an impact in other fields.”

Reference

Quan Y, Wei W, Ergin V, Rameshbabu AP, Huang M, Tian C, et al. (2023) Reprogramming by drug-like molecules leads to regeneration of cochlear hair cell-like cells in adult mice. Proc Nat Acad Sci 120(17):e2215253120.