Olivocochlear changes associated with aging predominantly affect the medial olivocochlear system
Author
dc.contributor.author
Vicencio Jiménez, Sergio
Author
dc.contributor.author
Weinberg, Madison M.
Author
dc.contributor.author
Bucci Mansilla, Giuliana
Author
dc.contributor.author
Lauer, Amanda M.
Admission date
dc.date.accessioned
2022-04-28T16:21:14Z
Available date
dc.date.available
2022-04-28T16:21:14Z
Publication date
dc.date.issued
2021
Cita de ítem
dc.identifier.citation
Frontiers in Neuroscience September 2021 Volume 15 Article 704805
es_ES
Identifier
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10.3389/fnins.2021.704805
Identifier
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https://repositorio.uchile.cl/handle/2250/185164
Abstract
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Age-related hearing loss (ARHL) is a public health problem that has been associated with negative health outcomes ranging from increased frailty to an elevated risk of developing dementia. Significant gaps remain in our knowledge of the underlying central neural mechanisms, especially those related to the efferent auditory pathways. Thus, the aim of this study was to quantify and compare age-related alterations in the cholinergic olivocochlear efferent auditory neurons. We assessed, in young-adult and aged CBA mice, the number of cholinergic olivocochlear neurons, auditory brainstem response (ABR) thresholds in silence and in presence of background noise, and the expression of excitatory and inhibitory proteins in the ventral nucleus of the trapezoid body (VNTB) and in the lateral superior olive (LSO). In association with aging, we found a significant decrease in the number of medial olivocochlear (MOC) cholinergic neurons together with changes in the ratio of excitatory and inhibitory proteins in the VNTB. Furthermore, in old mice we identified a correlation between the number of MOC neurons and ABR thresholds in the presence of background noise. In contrast, the alterations observed in the lateral olivocochlear (LOC) system were less significant. The decrease in the number of LOC cells associated with aging was 2.7-fold lower than in MOC and in the absence of changes in the expression of excitatory and inhibitory proteins in the LSO. These differences suggest that aging alters the medial and lateral olivocochlear efferent pathways in a differential manner and that the changes observed may account for some of the symptoms seen in ARHL.
es_ES
Publisher
dc.publisher
Frontiers Media
es_ES
Type of license
dc.rights
Attribution-NonCommercial-NoDerivs 3.0 United States