Scientists at the Indian Institute of Science Education and Research (IISER) Mohali, Punjab, have discovered a protein mutation that could pave the way for improved treatments for hearing loss in the elderly.
The research team, led by Sabyasachi Rakshit, focused on Cadherin-23, a protein critical for hearing in vertebrates. Found in the inner ear’s hair cells, this protein plays a vital role in converting sound waves into electrical signals that the brain interprets.
In experiments with mice, the team found that a mutation in Cadherin-23 led to improper protein folding, disrupting sound transmission in the inner ear. This caused progressive hearing loss in the animals.
Using a magnetic tweezer, the scientists exposed three variants of Cadherin-23—S47, V47, and P47—to mechanical forces. They discovered that the V47 variant was the most stable, able to withstand significant stress, while P47, the mutant version, unfolded quickly, which likely contributed to hearing impairment.
The study also showed that the P47 variant couldn’t tolerate repeated mechanical stresses mimicking natural sound-induced forces, providing further insight into how hearing loss occurs over time.
These groundbreaking findings, published in Nature Communications, could lead to new approaches to treating hearing loss by correcting this protein anomaly. However, the researchers emphasized that while this discovery offers an important piece of the puzzle, it may not represent the entire mechanism behind hearing loss in humans.
With over 1.5 billion people worldwide suffering from some form of hearing loss, including 430 million with disabling hearing loss (according to WHO), this discovery could represent a significant step toward improving treatment options for millions of people.
