Cypermethrin induces cell injury in primary cortical neurons of C57BL/6 mice by inhibiting Nrf2/ARE signaling pathway / 南方医科大学学报

OBJECTIVE@#To study the role of Nrf2/ARE signaling pathway in cypermethrin-induced oxidative stress and apoptosis of cerebral cortex neurons in C57BL/6 mice.@*METHODS@#The cortical neurons of C57BL/6 mice were cultured and identified, and a cypermethrin-induced cell injury model was established by treating the cells with 0, 25, 50 and 100 μmol/L of cypermethrin for 48 h. CCK-8 assay was used to analyze the effects of cypermethrin on the cell viability, and the fluorescence probe DCFH-DA was used for detecting intracellular reactive oxygen species (ROS); flow cytometry was performed for determining the apoptosis rate of the cells. The mRNA and protein expression levels of Nrf2 and its downstream genes HO-1 and NQO1 were detected using qPCR and Western blotting.@*RESULTS@#Exposure to cypermethrin at different doses inhibited the viability of the cultured cortical neurons. With the increase of cypermethrin dose, the viability of the neurons decreased progressively, the intracellular ROS and the cell apoptosis rate increased, and the neuronal injury worsened. At the dose of 50 and 100 μmol/L, cypermethrin significantly down-regulated the expressions of HO-1, NQO1 and Nrf2 at both the mRNA and protein levels in the cells ( < 0.01).@*CONCLUSIONS@#Cypermethrin exposure shows a dose-dependent neurotoxicity by inhibiting Nrf2/ARE signaling pathway, down-regulating the expression of Nrf2 and its downstream genes HO-1, NQO1 mRNA and protein, and inducing oxidative damage and apoptosis in primary mouse cortical neurons, .

Effects of dexamethasone on MRL/Ipr mice with systemic lupus erythematosus complicated with cognitive dysfunction / 中南大学学报(医学版)

Objective:To evaluate the effects of dexamethasone on systemic lupus erythematosus complicated with cognitive dysfunction.Methods:Ten wild type mice and 20 MRL/lpr mice were applied for the research.MRL/lpr mice were randomly assigned to a MRL/lpr group and a MRL/lpr + dexamethasone (1.5 mg/kg) group.Interleukin-6 (IL-6),IL-1β,and tumor necrosis factor alpha (TNF-α) in serum and hippocampus were detected.The protein phosphorylation levels of phosphoinositide 3-kinase (P-PI3K),protein kinase B (P-Akt),NF-kappa-B inhibitor alpha (P-IκBa) and nuclear transcription factor kappa-B p65 (P-NF-κB p65) were detected by Western blot,the level of P-NF-κB p65 also was detected by immunohistochemistry.Results:Treatment with dexamethasone (1.5 mg/kg) alleviated the cognitive dysfunction and decreased the levels of IL-6,IL-1 β and TNF-α in serum and hippocampus,and reduced the levels of P-PI3K,P-Akt,P-IκBa and P-NF-κB p65 in hippocampus in MRL/lpr mice.Conclusion:Dexamethasone may play a protective role in the cognitive function by decreasing the levels of TNF-α and IL-1 β in the hippocampus of MRL/lpr lupus mice.