Preventing Hearing Loss and Restoring Hearing: A New Outlook

People with hearing loss represent one of the largest disability groups worldwide, and the prevalence of hearing loss is predicted to rise with an ageing population. Substantial progress has been made towards understanding some of the biological processes involved in the development of hearing impairment as well as therapeutic ways to prevent or mitigate the hearing loss. For example, we now have a better understanding of the maintenance and regeneration of the sensorineural tissues in the cochlea. The sensory hair cells in the cochlea can potentially be regenerated by reactivating genes that control their development, and various types of stem cells can be transformed into sensory hair cells or auditory neurones. In addition, drugs that reduce oxidative stress or prevent apoptosis have been shown to protect hearing from excessive noise and ototoxic drugs. Furthermore, our knowledge of central auditory changes associated with the peripheral injury or auditory processing problems is rapidly increasing. In this special issue, we collected review and original research articles presenting current concepts in development, screening, prevention, rehabilitation, and therapeutic management of hearing loss. It is our wish to increase interest in hearing loss research with this special issue and further accelerate the development of novel therapies for hearing disorders. Several papers are concerned with the therapeutic management of sensorineural hearing loss, including pharmacological and cell replacement therapies. Other papers deal with the mechanisms, biomarkers, early detection, and auditory plasticity in hearing loss. Finally, one paper analyses the risk factors for noise-induced tinnitus. The review paper by S. Irving and colleagues (Bionics Institute, University of Melbourne) presents the benefits of electroacoustic stimulation to cochlear implant recipients with residual hearing. This review also outlines the experimental and clinical strategies aimed at promoting the survival of sensory hair cells and spiral ganglion neurones in cochlear implant recipients. Auditory nerve regeneration by human neural precursor cells (HNPC) was demonstrated by Y. Jiao et al. The study shows that BDNF supplementation improves the survival of HNPC and their migration into the brainstem in the vicinity of the cochlear nucleus. However, functional improvement after implantation of HNPC is yet to be confirmed. Pharmacological treatment of acute noise-induced hearing loss (NIHL) is a relatively novel research field. S. M. Vla-jkovic et al. report that adenosine amine congener (ADAC), a selective A 1 adenosine receptor agonist, mitigates NIHL in a dose-and time-dependent manner. ADAC thus holds potential as a clinical treatment for noise-induced cochlear …