Oxidative stress plays a critical role in cognitive dysfunction and neuronal death associated with neurodegenerative diseases. Nrf2 is a transcription factor that plays a key role in cellular resistance to oxidative stress, but little i known about the physiological signals that regulate Nrf2 activity in the brain or how Nrf2 impacts neuronal function. My laboratory uses the model C. elegans to study new signaling pathways that modulate presynaptic function. We recently identified the Nrf2 homolog, SKN-1, as a regulator of presynaptic structure and function. We found that SKN-1/Nrf2 functions cell non- autonomously to regulate neurotransmitter secretion from neuromuscular junctions. We also found that neuroendocrine signaling from the nervous system confers organism-wide protection from the toxic effects of oxidative stress by activating SKN-1/Nrf2 in distal tissues. Here we seek to uncover the cellular and molecular mechanisms by which bidirectional communication between the nervous system and distal tissues promotes an adaptive response to oxidative stress through the regulation of neurotransmitter secretion.
In Aim 1, we will determine how SKN-1/Nrf2 activity is positively regulated by neuropeptide release from the nervous system.
In Aim 2, we will determine how reactive oxygen species promote neuropeptide release in vivo.
In Aim 3 we will determine how synaptic transmission is negatively regulated by cell non-autonomous SKN-1 activation. Nrf2 activation protects neurons form death in a variety of neurodegenerative disease models, and our research may uncover new endogenous activators of Nrf2, which may lead to the development of new therapeutics that can prevent or treat these diseases.

Public Health Relevance

Oxidative stress in the brain impacts synaptic function, and aberrant responses to oxidative stress are linked to neurodegenerative diseases and inflammation. Our research is focused on the fundamental mechanisms by which the Nrf2 oxidative stress response pathway is regulated in the brain and how it impacts synaptic function. Nrf2 activation protects neurons form death in a variety of neurodegenerative disease models, and our research may uncover new endogenous activators of Nrf2, which may lead to the development of new therapies that activate Nrf2.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
High Priority, Short Term Project Award (R56)
Project #
2R56NS071085-06A1
Application #
9222832
Study Section
Synapses, Cytoskeleton and Trafficking Study Section (SYN)
Program Officer
Gubitz, Amelie
Project Start
2010-07-01
Project End
2017-03-31
Budget Start
2016-04-01
Budget End
2017-03-31
Support Year
6
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Southern California
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
072933393
City
Los Angeles
State
CA
Country
United States
Zip Code
90032
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