Hearing loss is a prevalent issue that has a reputation for being largely irreversible. That story is about to change as recent research offers hope of potential reversibility. Hearing problems affect all age groups, but the burden is disproportionately borne by the elderly. Around half of those in their 70s suffer some hearing loss, possibly more as not all cases reach hospitals. Besides hearing aids and cochlear implants, no medical remedies exist for hearing loss. This absence of effective treatments significantly impacts affected individuals, causing isolation, low mood, and cognitive decline (Mick, Kawachi & Lin, 2014). It’s also a key dementia risk factor.
Hearing Loss
Activating Spns2 Gene Reverses Auditory Impairment
A recent study conducted on mice found that activating a specific gene can restore auditory function and protect sensory hair cells from further degeneration.
The researchers zeroed their focus on a specific type of hearing loss associated with a mutation in the Spns2 gene. This mutation leads to a failure to maintain the correct ionic environment in the sensory hair cells, resulting in a reduced endocochlear potential (EP). By activating the Spns2 gene at different stages of the hearing loss progression, the researchers were able to reverse the auditory impairment in the mice.
The results showed that activating the Spns2 gene early in the disease progression led to significant improvements in auditory function. The mice exhibited close to normal thresholds for auditory brainstem responses (ABR) at low to mid stimulus frequencies. Importantly, early activation of the gene also protected the sensory hair cells from further damage (Martelletti, Ingham & Steel, 2023).
Read Also: Researchers Reverse Hearing Loss by Regenerating Cochlear Hair Cells
The quickness of Intervention is Vital for Treatment Effectiveness
The study also found that there is a golden window when intervention must occur if hearing loss is to be reversed. The earlier the gene was activated, the better the restoration of auditory function. Delaying the activation of the gene resulted in less effective recovery. This suggests that early intervention in individuals with hearing loss may be crucial to prevent irreversible changes and secondary degeneration of the hair cells.
Clinical Significance
What we can now reasonably conclude from these findings is that the type of hearing loss associated with EP deficiency can not only be halted but even reversed. This raises some new possibilities. Yes, might have worked in the odd mouse or two, but could such a breakthrough be replicated in humans? Further studies will be required to answer that question substantively.
Read Also: The Use of Cochlear Implants in Adults With Hearing Loss Could Prevent Dementia
Conclusion
Yes, hearing loss might not be as irreversible as we have always thought. Reversing it could be achieved by increasing the level of transcription of the SPNS2 gene. This development must come as much welcome news to those with one form of hearing impairment or the other.
References
Martelletti, E., Ingham, N.J., Steel, K.P. 2023. Reversal of an existing hearing loss by gene activation in Spns2 mutant mice. PNAS. 120(34) e2307355120. Available at: https://doi.org/10.1073/pnas.2307355120.
