Persistent DNA damage alters the neuronal transcriptome suggesting cell cycle dysregulation and altered mitochondrial...

Area of Science:

• Neuroscience
• Molecular Biology
• Genetics

Background:

• Oxidative DNA damage impacts neuronal cell cycle and DNA damage response (DDR).
• Chronic oxidative environments can impair DNA repair, leading to damage accumulation.
• Brain aging and neurodegeneration are linked to oxidative stress and DNA damage.

Purpose of the Study:

• To investigate the effects of persistent oxidative DNA damage on neuronal function.
• To characterize the neuronal transcriptome and molecular responses to chronic oxidative stress.

Main Methods:

• Developed an in vitro model of persistent oxidative DNA damage in immortalized post-mitotic neurons using hydrogen peroxide.
• Utilized microarray analysis for comprehensive transcriptome profiling.
• Employed quantitative polymerase chain reaction (qPCR) and functional assays for validation.

Main Results:

• Persistent DNA damage significantly altered gene expression related to cell cycle regulation, DDR, DNA repair, and mitochondrial function.
• Evidence of an active DDR response to replication stress and alterations in the mitochondrial electron transport chain.
• Confirmed hyperactivation of mitochondrial Complex I in response to persistent DNA damage.

Conclusions:

• Persistent oxidative DNA damage induces significant molecular changes in neurons, including altered gene expression and mitochondrial dysfunction.
• Hyperactivation of mitochondrial Complex I may exacerbate oxidative stress, contributing to neuronal dysfunction.
• These findings provide insights into mechanisms underlying neurodegeneration associated with oxidative stress.