Continuous liquid feeding: New method to study pesticides toxicity in Drosophila melanogaster.

Fly fruit Drosophila melanogaster (DM) has been extensively employed as an in vivo model system to study pesticides toxicity. Pesticide administration to the fly traditionally involves feeding in an agar-gelled feed fly's medium (AM). However, AM method has several limitations such as uncertainty regarding the bioavailability and amount of pesticides ingested. And also high manipulation of the treated flies. We developed a new method of exposure the flies to pesticides, called Continuous Liquid Feeding (CLF). This method successfully delivers food to the flies at much higher concentrations than the AM method, and requires little manipulation of flies under treatment.

Paraquat exposure-induced Parkinson's disease-like symptoms and oxidative stress in Drosophila melanogaster: Neuroprotective effect of Bougainvillea glabra Choisy.

Extracts from the leaves of Bougainvillea glabra Choisy are used in traditional medicines, but their actions on the central nervous system have not been studied. In the present study, we investigated the potential neuroprotective effects of Bougainvillea glabra Choisy leaf extract (BG extract) against paraquat (PQ)-induced neurotoxicity. Male adult wild-type flies (1- 4days old) were exposed to PQ (3.5mM) and/or BG extract (120µg/mL) through food for 4days. PQ-fed flies had decreased locomotor capacity in negative geotaxis and crossing number assays and had a higher incidence of mortality than the control group. PQ neurotoxicity was also associated with a marked decrease in dopamine levels and increase in acetylcholinesterase (AChE) activity, reactive oxygen species (ROS) production and lipid peroxidation. Co-exposure to BG extract prevented mortality, and dopamine depletion, improved locomotor performance and decreased AChE activity, ROS production and lipid peroxidation. GC-MS and HPLC analyses of BG extract revealed the presence of many antioxidant compounds such as phytol, α,γ-tocopherol, squalene, stigmasterol, geranylgeraniol, quercetin, and caffeic, vanillic, coumaric, ferulic acids. Our results showed neuroprotective effects of BG extract, reflecting the presence of antioxidant compounds. Thus, we suggested that B. glabra leaves could be considered an effective agent in the prevention of neurological disorders, where dopamine depletion and/or oxidative stress are involved, as in Parkinson's disease (PD).