Dataset Information

Effects of Ageing on the Mitochondrial Genome in Rat Vestibular Organs.

ABSTRACT:

Background

Deterioration in vestibular function occurs with ageing and is linked to age-related falls. Sensory hair cells located in the inner ear vestibular labyrinth are critical to vestibular function. Vestibular hair cells rely predominantly on oxidative phosphorylation (OXPHOS) for energy production and contain numerous mitochondria. Mitochondrial DNA (mtDNA) mutations and perturbed energy production are associated with the ageing process.

Objective

We investigated the effects of ageing on mtDNA in vestibular hair and support cells, and vestibular organ gene expression, to better understand mechanisms of age-related vestibular deficits.

Methods

Vestibular hair and supporting cell layers were microdissected from young and old rats, and mtDNA was quantified by qPCR. Additionally, vestibular organ gene expression was analysed by microarray and gene set enrichment analyses.

Results

In contrast to most other studies, we found no evidence of age-related mtDNA deletion mutations. However, we found an increase in abundance of major arc genes near the mtDNA control region. There was also a marked age-related reduction in mtDNA copy number in both cell types. Vestibular organ gene expression, gene set enrichment analysis showed the OXPHOS pathway was down regulated in old animals.

Conclusion

Given the importance of mtDNA to mitochondrial OXPHOS and hair cell function, our findings suggest the vestibular organs are potentially on the brink of an energy crisis in old animals.

SUBMITTER: Bigland MJ

PROVIDER: S-EPMC6388513 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Effects of Ageing on the Mitochondrial Genome in Rat Vestibular Organs.

Bigland Mark J MJ Brichta Alan M AM Smith Doug W DW

Current aging science 20180101 2

<h4>Background</h4>Deterioration in vestibular function occurs with ageing and is linked to age-related falls. Sensory hair cells located in the inner ear vestibular labyrinth are critical to vestibular function. Vestibular hair cells rely predominantly on oxidative phosphorylation (OXPHOS) for energy production and contain numerous mitochondria. Mitochondrial DNA (mtDNA) mutations and perturbed energy production are associated with the ageing process.<h4>Objective</h4>We investigated the effect ...[more]

PMID: 30777575

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Dataset Information

Effects of Ageing on the Mitochondrial Genome in Rat Vestibular Organs.

Background

Objective

Methods

Results

Conclusion

Publications

Effects of Ageing on the Mitochondrial Genome in Rat Vestibular Organs.

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