Dopaminergic Dysfunction in Mammalian Dopamine Neurons Induced by Simazine Neurotoxicity

Many studies have shown that the pollutant simazine (6-chloro-N,N′-diethyl-1,3,5-triazine-2,4-diamine), which has been overused, inhibits the proliferation of mammalian dopaminergic cells, and affects the developmental differentiation of mammalian dopaminergic neurons. However, few studies have shown the effects of simazine on dopaminergic metabolism in these cells. Therefore, we aim to examine the metabolic effects of simazine exposure in mouse dopaminergic progenitor neurons (MN9D) at different exposure times. The cells were treated with simazine at 0, 150, 300 and 600 µM for 12, 24 and 48 h, respectively. The content of dopamine in these cells was then examined using the enzyme-linked immunosorbent assay (ELISA) kit. Real-time quantitative polymerase chain reaction (PCR) and western blotting were performed to analyze the mRNA and protein expression of aromatic amino acid decarboxylase (AADC), tyrosine hydroxylase (DYT5b), dopamine transporter (DAT), monoamine vesicular transporter 2 (VMAT2), monoamine oxidase (MAO) and catechol-O-methyl transferase (COMT). The results showed that simazine influenced the metabolism of dopamine and led to a decrease in dopamine level in these cells which may eventually lead to neurological disorders of the dopaminergic system.