Avaliação da neurotoxicidade induzida por timerosal em Drosophila melanogaster: implicações sobre a rota dopaminérgica

Abstract

Thimerosal (THIM) is a compound which has been used since the early 20th century as a preservative in vaccines. Since then, the effects of this compound on living organisms have been discussed over decades. It has been speculated that one of the possible targets of this compound is the central nervous system (CNS). In this context, one of the complex systems that may be the target of this exposure is dopaminergic, responsible for several complex behaviors. Within this framework, the overall aim of this study is to assess the damage caused by TIM-induced neurotoxicity in Drosophila melanogaster. Evaluating the damage caused by TIM were performed survival, behavioral, oxidative, stress and dopamine synthesis route markers. Animals were divided into two groups: control and TIM 25 μM, where the flies were exposed for 4 days. Our results demonstrate that D. melanogaster exposed to TIM tabled amendments in tyrosine hydroxylase expression (DmTyrH) and its activity, together with altered levels of dopamine (DA) that led to impaired motor behavior. These amendments were also accompanied by increased oxidative stress and reduced acetylcholinesterase (AChE) activity and also the survival of flies. These results suggest the initial role of DmTyrH mediated by TIM, leading to changes in the function of AD and behavioral abnormalities, therefore leading to neurotoxicity which are related to oxidative stress.