Paraquat-Induced Movement Disorder in Relation to Oxidative Stress-Mediated Neurodegeneration in the Brain of Drosophila melanogaster.

Exposure to pesticides like paraquat (PQ) is considered as a risk factor for Parkinson's disease (PD). PQ has been shown to induce PD-like phenotype in experimental animals. Drosophila, a valuable laboratory model organism, is widely used to study neurodegenerative disorders including PD. The acute (single dose) PQ model of PD in Drosophila is associated with high mortality as well as reversibility of locomotor deficits and, therefore, does not replicate the disease phenotype. We have investigated the relevance of the acute and multiple (sublethal) dose of PQ to induce PD-like symptoms in Drosophila and shown that multiple-dose of PQ induces irreversible locomotor impairment without significant mortality. Our study has provided ultrastructural evidence for neurodegeneration involving mitochondrial damage in the brain caused by free radical-induced oxidative stress, which leads to locomotor impairment in Drosophila. The multiple (sublethal) dose of PQ could be an appropriate Drosophila model to induce PD-like symptoms of movement disorder associated with neurodegeneration, which could be useful to evaluate neuroprotective compounds.