去氢丹参新酮对神经炎症的抑制作用及机制研究

The anti-neuroinflammatory effects of dehydromiltirone and related mechanisms

目的研究去氢丹参新酮对脂多糖(lipopolysaccharide,LPS)诱导小胶质细胞系BV2细胞产生炎症反应的抑制作用及其作用机制。方法不同浓度去氢丹参新酮预孵育BV2细胞后,用LPS刺激引起神经炎症相关反应。Griess试剂法检测去氢丹参新酮对活化的BV2细胞产生一氧化氮(nitric oxide,NO)的影响,ELISA检测细胞上清液中TNF-α和IL-6的释放量,Confocal观察小胶质细胞表面活化标志物MAC-1表达量的变化,Western blot检测炎症相关信号通路蛋白表达的变化。结果去氢丹参新酮可明显抑制LPS刺激BV2细胞产生的炎症因子包括NO、TNF-α和IL-6的水平,同时抑制一氧化氮合酶、环氧合酶-2等炎症相关蛋白的表达和小胶质细胞表面活化标志物MAC-1的表达。机制研究发现,去氢丹参新酮对PI3K/Akt的过度磷酸化以及NF-κB的过度活化都有明显的抑制作用。结论去氢丹参新酮具有很好的抑制神经炎症活性,其作用机制可能是通过PI3K/Akt信号通路抑制NF-κB的活化而实现的。

Aim To investigate the anti-neuroinflammatory activities of dehydromiltirone and the underlying mechanisms in LPS-stimulated microglial cell line BV2 cells.Methods BV2 cells were pre-treated with dehydromiltirone,then stimulated by LPS.The levels of nitric oxide(NO) were measured by Griess assay,and the concentrations of pro-inflammatory cytokines were measured by ELISA assay.Confocal fluorescence microscopy was used to measure the expression of MAC-1,the biomarker of activated BV2 cells.The levels of—inducible nitric oxide synthase(iNOS),cyclooxygenase-2(COX-2),NF-κB and PI3K/Akt were determined by Western blot analysis.Results The treatment of dehydromiltirone significantly inhibited the production of NO,TNF-α and IL-6,attenuated the expression of iNOS and COX-2 protein,and dampened the microglial activation in LPS-stimulated BV2 cells.The mechanistic study revealed that dehydromiltirone inhibited the phosphorylation of PI3 K and Akt in LPSstimulated BV2 cells,and decreased NF-κB activation by suppressing the degradation of IκB.Conclusion dehydromiltirone shows significant anti-neuroinflammatory effects through inhibiting PI3K/Akt phosphorylation and then inhibiting NF-κB signaling pathway.