Pequi enriched diets protect Drosophila melanogaster against paraquat-induced locomotor deficits and oxidative stress

Abstract

The species Caryocar coriaceum Wittm (C. coriaceum), is popularly employed in northeast of Brazil for culinary purposes and in folk medicine. The oil from its fruit, deignated Pequi, is commonly used to treat inflammatory problems, and its leaves to treat viral infections. However, comprehensive knowledge regarding the pharmacological properties attributed to these plant parts is still scarce. Thus, this study aimed to explore the in vivo antioxidant potential of aqueous extract of the leaves (AEL) and Pequi pulp oil (PPO) on the pro-oxidative effects induced by paraquat (PQ) using Drosophila melanogaster (D. melanogaster) as a model. These flies were fed with either standard or AEL and PPO supplemented diets prior to (pre-treatment for 7 days) or concomitantly (co-treatment for 5 days) with PQ. D. melanogaster administered PQ exhibited locomotor deficits and a higher rate of mortality. PQ induced significant changes in the antioxidant/oxidant status of D. melanogaster, including significant (1) increase in levels of reactive oxygen species (ROS) and lipid peroxidation; (2) elevation in the activity of antioxidant enzymes catalase (CAT) and glutathione-S-transferase (GST) and marked up-regulation in mRNA expression of stress-related genes for CAT, superoxide dismutase (SOD), thioredoxin reductase and Keap-1. Aside for mortality rates, AEL and PPO treatments reduced PQ-induced oxidative stress and motor impairments. No apparent evidence of toxicity was observed in D. melanogaster fed with AEL and PPO alone. Our findings provide evidence that AEL and PPO may confer protection against oxidant conditions by stimulating antioxidant responses.

Keywords: Caryocar coriaceum; Drosophila melanogaster; Pequi; oxidative stress; paraquat.