Pathogenesis of presbycusis in animal models: A review

Presbycusis is the most common cause of hearing loss in aged subjects, reducing individual's communicative skills. Age related hearing loss can be defined as a progressive, bilateral, symmetrical hearing loss due to age related degeneration and it can be considered a multifactorial complex disorder, with both environmental and genetic factors contributing to the aetiology of the disease.The decline in hearing sensitivity caused by ageing is related to the damage at different levels of the auditory system (central and peripheral). Histologically, the aged cochlea shows degeneration of the stria vascularis, the sensorineural epithelium, and neurons of the central auditory pathways. The mechanisms responsible for age-associated hearing loss are still incompletely characterized.This work aims to give a broad overview of the scientific findings related to presbycusis, focusing mainly on experimental studies in animal models.

Research Highlights
► Presbycusis has a multifactorial pathogenesis related to genetic and environmental factors.
► Animal models are used to represent the different patterns of presbycusis
► Mice are the best model for studying the cellular and genetic bases of age-related hearing loss.
► In C57BL/6J mice aging is associated to reduced vascularization and endothelial dysfunction. Vascular dysfunction might play a pivotal role in presbycusis.