Neuroprotective effect of Decalepis hamiltonii in paraquat-induced neurotoxicity in Drosophila melanogaster: biochemical and behavioral evidences.

In this paper, we have demonstrated for the first time, the antioxidant and neuroprotective effects of Decalepis hamiltonii (Dh) root extract against paraquat (PQ)-induced oxidative stress and neurotoxicity in Drosophila melanogaster. Exposure of adult D. melanogaster (Oregon K) to PQ induced oxidative stress as evidenced by glutathione depletion, lipid peroxidation and enhanced activities of antioxidant enzymes such as catalase, superoxide dismutase as well as elevated levels of acetylcholine esterase. Pretreatment of flies by feeding with Dh extract (0.1, 0.5 %) for 14 days boosted the activities of antioxidant enzymes and prevented the PQ-induced oxidative stress. Dietary feeding of Dh extract prior to PQ exposure showed a lower incidence of mortality and enhanced motor activities of flies in a negative geotaxis assay; both suggesting the neuroprotective potential of Dh. Based on the results, we contemplate that the roots of Dh might prevent and ameliorate the human diseases caused by oxidative stress. The neuroprotective action of Dh can be attributed to the antioxidant constituents while the precise mechanism of its action needs further investigations.