Increased mitochondrial DNA damage and decreased base excision repair in the auditory cortex of D-galactose-induced aging rats.

Mol Biol Rep

Department of Otolaryngology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, China.

Published: August 2011

Aging has been associated with mitochondrial DNA (mtDNA) common deletion (CD). Age changes in the central auditory system are well known to affect speech perception. Base excision repair (BER) is the major type of DNA repair in mitochondria. The current study was designed to investigate potential causative mechanisms of central presbycusis by using a rat mimetic aging model induced by subcutaneous administration of D-galactose (D-gal). Quantitative real-time PCR and Western blotting analyses were performed to identify the mtDNA 4834 bp deletion and selected mitochondrial DNA repair enzymes, DNA polymerase γ (pol γ) and 8-oxoguanine DNA glycosylase (OGG1). Cell apoptosis in the auditory cortex was detected using terminal deoxynucleotidyltransferase mediated UTP nick-end labeling (TUNEL). Our data showed that mtDNA 4834 bp deletion and TUNEL-positive cells were significantly increased and the expression of pol γ and OGG1 were remarkably down-regulated in the auditory cortex in D-gal-treated rats compared to control rats. During aging, increased mtDNA damage likely results from decreased DNA repair capacity in the auditory cortex. DNA repair enzymes such as pol γ and OGG1 may provide novel pharmacological targets to promote DNA repair and rescue the central auditory system in patients with degenerative diseases.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11033-010-0476-5DOI Listing

Publication Analysis

Top Keywords

dna repair
20
auditory cortex
16
mitochondrial dna
12
dna
9
damage decreased
8
base excision
8
excision repair
8
rats aging
8
central auditory
8
auditory system
8

Similar Publications

Homologous recombination is a largely error-free DNA repair mechanism conserved across all domains of life and is essential for the maintenance of genome integrity. Not only are the mutations in homologous recombination repair genes probable cancer drivers, some also cause genetic disorders. In particular, mutations in the Bloom (BLM) helicase cause Bloom Syndrome, a rare autosomal recessive disorder characterized by increased sister chromatid exchanges and predisposition to a variety of cancers.

View Article and Find Full Text PDF

RecQ helicases, highly conserved proteins with pivotal roles in DNA replication, DNA repair and homologous recombination, are crucial for maintaining genomic integrity. Mutations in RECQL4 have been associated with various human diseases, including Rothmund-Thomson syndrome. RECQL4 is involved in regulating major DNA repair pathways, such as homologous recombination and nonhomologous end joining (NHEJ).

View Article and Find Full Text PDF

Phosphorylation-dependent WRN-RPA interaction promotes recovery of stalled forks at secondary DNA structure.

Nat Commun

January 2025

Mechanisms, Biomarkers and Models Section - Genome Stability Group, Department of Environment and Health, Istituto Superiore di Sanità, Viale Regina Elena, 299 - 00161, Rome, Italy.

The WRN protein is vital for managing perturbed replication forks. Replication Protein A strongly enhances WRN helicase activity in specific in vitro assays. However, the in vivo significance of RPA binding to WRN has largely remained unexplored.

View Article and Find Full Text PDF

TP53 mutations are recognized to correlate with a worse prognosis in individuals with non-small cell lung cancer (NSCLC). There exists an immediate necessity to pinpoint selective treatment for patients carrying TP53 mutations. Potential drugs were identified by comparing drug sensitivity differences, represented by the half-maximal inhibitory concentration (IC50), between TP53 mutant and wild-type NSCLC cell lines using database analysis.

View Article and Find Full Text PDF

Metastatic uveal melanoma (UM) patients often initially present with limited symptoms despite a poor prognosis, complicating communication with patients and caregivers. Early Together (NCT04728113) is a randomized Phase III trial that integrates early palliative care through systematic joint visits involving the palliative care team and the medical oncologist, compared with standard oncological care, in 162 metastatic UM patients beginning systemic treatment. This collaboration aims to enhance patient functioning, improve quality of life and facilitate coping mechanisms.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!