Background: Parkinson’s disease (PD) is a progressive neurodegenerative disorder. Characterized by the loss of dopamine (DA) neurons in the substantia nigra (SN), the majority of PD cases are idiopathic with a small percentage being genetically determined. Studies of both sporadic and inherited forms of PD point to mitochondrial (mito) dysfunction and oxidative stress as underlying pathophysiological mechanisms.
Objective: 1. Optimize primary screening assay employing the chemo-genetic larval zebrafish DA neuron degeneration model. 2. Carry out a primary screen of compounds library through organism-based high content imaging to find candidate hits.
Methods: we have developed a chemo-genetic DA neuron degeneration model in larval zebrafish. This model expresses the bacterial enzyme nitro-reductase (NTR) in DA neurons. Upon addition of the prodrug metronidazole (MTZ, a commonly used antibiotic), NTR converts MTZ into a toxic compound that renders DA neuron degeneration. For screening, we have established whole organism-based high content imaging platform from which we can directly visualize the integrity of these neurons
Results: We have figured out the best conditions of Mtz treatment for our model and tested Z’ factor (Z’=0.38) for assay evaluation and validation. For screening, we have validated 40 pairs of candidate hit compounds selected from a primary screen of 3,000 compounds and found a potential compound that led to a significant increase in DA neuron fluorescent intensity compared to MTZ-treated negative controls.