Alleviation of arsenic-induced neurobehavioral defects with selenium in the larvae of Zaprionus indianus.

Selenium is an essential antioxidative micronutrient. This study was conducted to characterize the arsenic toxicity induced on the African fig fly, Zaprionus indianus, and its possible amelioration by selenium. We used computational tools and in vivo experiments to elucidate the mechanism of action of arsenic and selenium on Z. indianus larvae. We conducted experiments to study neurobehavioral parameters including learning and memory ability test and crawling and contraction assays. Our in silico study revealed twelve primary targets of arsenic trioxide. The gene ontology annotation of primary and secondary targets of arsenic trioxide revealed selenocysteine metabolic processes as one of the most reliable targets. To validate our in silico data, we analyzed the effect of arsenic trioxide on larvae of Z. indianus and tested the possible amelioration by sodium selenite supplementation. Our data demonstrated that the arsenic trioxide deteriorated the learning and memory ability of 2nd instar larvae of Z. indianus and such effect was reversed by sodium selenite supplementation. Furthermore, crawling and contraction assay done on 3rd instar larvae showed that there was reduction in both parameters upon arsenic trioxide exposure, which was restored with sodium selenite supplementation. Altogether, our computational and in vivo results strongly indicated that the neurobehavioral defects induced by arsenic trioxide on the larvae of Z. indianus can be successfully alleviated in the presence of sodium selenite.