1,2-Dichloroethane induces apoptosis in the cerebral cortexes of NIH Swiss mice through microRNA-182-5p targeting phospholipase D1 via a mitochondria-dependent pathway

1,2-Dichloroethane (1,2-DCE) is a pervasive environmental pollutant found in ambient and residential air, as well as ground and drinking water. Overexposure to it results in cortex edema, in both Animals and humans. 1,2-DCE induces Apoptosis in the cerebellum, liver and testes. This promotes the hypothesis that 1,2-DCE may induce Apoptosis in the cortex as brain edema progresses. To validate our hypothesis, 40 NIH male mice were exposed to 0, 100, 350, 700 mg/m³ 1,2-DCE by whole-body dynamic inhalation for 28 consecutive days. MicroRNA (miRNA) and mRNA microarray combined with TdT-mediated dUTP nick-end labeling, flow cytometry, and mitochondrial membrane potential (mtΔΨ) measurement were applied to identify the cortex Apoptosis pathways' specific responses to 1,2-DCE, in vitro and in vivo. The results showed that 1,2-DCE caused brain edema and increased Apoptosis in the mouse cortexes. We confirmed that 1,2-DCE induced increased Apoptosis via mitochondrial pathway, both in vitro and in vivo, as evidenced by increased Caspase-3, cleaved Caspase-3, Cytochrome c and Bax expression, and decreased Bcl-2 expression. Additionally, mtΔΨ decreased after 1,2-DCE treatment in vitro. 1,2-DCE exposure increased miR-182-5p and decreased Phospholipase D1 (PLD1) in the cerebral cortex of mice. MiR-182-5p overexpression and PLD1 inhibition reduced mtΔΨ and increased astrocyte Apoptosis, yet miR-182-5p inhibition alleviated the 1,2-DCE-induced PLD1 down-regulation and the increased Apoptosis. Finally, PLD1 was confirmed to be a target of miR-182-5p by luciferase assay. Taken together, our findings indicate that 1,2-DCE exposure induces Apoptosis in the cortex via a mitochondria-dependent pathway. This pathway is regulated by a miR-182-5p⊣PLD1 axie.