Rotenone, an active ingredient extracted from tropical plants such as timbo, is a
substance widely used in the Amazon region as a pesticide in the regional fishing. This
neurotoxic reproduces many aspects of Parkinson's Disease (PD) in animal models in
vivo and in vitro, including nigrostriatal dopaminergic degeneration and formation of
cytoplasmic inclusions similar to Lewy bodies. One hypothesis is that exposure to
environmental factors, along with aging and genetic factors increase the risk of
disease development. By causing changes in oxidative metabolism, since it is an
inhibitor of mitochondrial complex I, rotenone increases the production of reactive
oxygen species (ROS). The excess of ROS has detrimental effects such as
peroxidation of membrane lipids and aggression to tissue proteins and membranes.
The consequences of oxidative stress in neurons of the nigrostriatal pathway lead to
changes of motion, balance and changes in fine motor control. In this study, male
Wistar rats, divided into control groups (n = 12) and treated (n = 13) underwent
intraperitoneal administration of rotenone for 30 days. We evaluated the occurrence of
lipid peroxidation in brain regions directly involved in PD as the substantia nigra and
the striatum as well as other regions such as cerebral cortex, cerebellum,
hippocampus and hypothalamus. Cortex, cerebellum, striatum and substantia nigra
were the areas where there was statistical difference in outcomes between treated and
control groups. Behavioral tests performed in the first, fifteenth and thirtieth days,
showed motor abnormalities including decreased locomotor activity and decreased
ability to adopt a standing position with and without support. So it is not possible to rule
out the possibility that such changes are a result of dysfunction in multiple functions in
various areas of the nervous system, including or not the nigrostriatal pathway. As the
mechanisms of toxicity induced by rotenone are still not fully understood, this study
aimed to further investigate the induction of oxidative stress in peripheral tissues.
Tissues analyzed included the proximal duodenum, liver and kidney. The results
showed some degree of peroxidation mainly in liver and kidney.
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