Avaliação da toxidade do herbicida sulfrentazone (Boral 500SC) em Drosophila melanogaster

Abstract

The sulfentrazone pesticide is widely used in agriculture for the pre and post-emergent and post-planting weeds that may harm agricultural production. This herbicide belongs to the group of Aryl Triazolones, having as mechanism of action the inhibition of the enzyme protoporphyrinogen oxidase (Ppox). By inhibiting this enzyme it leads to accumulation of intermediates, which when exposed to sunlight, generate reactive species of oxygen (ROS, reactive oxygen species) leading to cell damage, later cell and organism death. These reactive species are also produced in the human metabolism and there are enzymes specialized in metabolizing them to prevent damage cell phones. Although this repair system occurs, when the human organism is exposed to certain endogenous and exogenous molecules, such as heavy metals and pesticides, there may be a overproduction of ROS, causing cell damage. These damages are indicated as possible causing neurodegenerative diseases such as Parkinson's disease and Alzheimer's. To assess the neurotoxicity of sulfentrazone, the model was used experimental study of Drosophila melanogaster, with locomotor and enzymatic tests for the expression of the effects caused by sulfentrazone in its commercial formulation (Boral 500SC®). Through the survival rate of flies against different concentrations of the pesticide (0.1; 0.5 and 1 mM), it was found that the pesticide has a high toxicity, almost leading to total death of the flies after four days of exposure. With the results of Negative geotaxis and dopamine dosage, it was possible to observe that sulfentrazone induced locomotor deficit as well as depletion of dopamine levels. Analysis of the markers oxidative (dosage of ROS and TBARS) did not show significant results, leaving as the herbicide induces dopaminergic decrease in treated flies. Through from this study it was clear that sulfentrazone induces neurotoxicity in D. melanogaster, but the neurotoxicity mechanism of this herbicide is not yet fully understood.