[关键词]
[摘要]
目的 探讨橄榄苦苷对脂多糖(LPS)诱导的小鼠腹腔巨噬细胞(RAW264.7)炎症的保护作用及机制。方法 MTT法检测橄榄苦苷(0、10、20、40 μmol/L)对RAW264.7细胞活性的影响;用橄榄苦苷(10、20、40 μmol/L)预处理细胞1 h后,LPS诱导炎症模型,Griess试剂检测细胞内Nitrite释放;Western blotting方法检测细胞iNOS、COX-2、Nrf2、Keap-1、HO-1、NQO1蛋白表达水平;流式细胞仪检测细胞内NO、ROS、Ca2+的水平;荧光显微镜检测线粒体膜电位(MMP)水平;ELISA法检测细胞上清液中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)的释放。结果 与模型组比较,橄榄苦苷组Nitrite释放水平显著降低(P<0.05、0.01、0.001),iNOS、COX-2蛋白的表达显著降低(P<0.001),NO的产生显著减少(P<0.05、0.01);TNF-α、IL-6的释放受到显著抑制(P<0.001);Ca2+释放受到显著抑制(P<0.01);ROS生成受到显著抑制(P<0.01);JC-1单体降低,恢复聚合物状态(红色荧光变多),MMP稳定性增强;Keap1蛋白表达显著降低, Nrf2、HO-1、NQO1蛋白的表达均显著升高(P<0.05、0.01、0.001)。结论 橄榄苦苷对LPS诱导的RAW264.7细胞炎症具有抑制作用,其作用机制可能与激活Nrf2/HO-1信号通路相关。
[Key word]
[Abstract]
Objective To explore the anti-inflammatory activity of Oleuropein in LPS-stimulated RAW264.7 cells via Nrf2/HO-1 signaling pathway. Methods MTT method was used to detect the effect of oleuropein (0, 10, 20, 40 μmol/L) on the activity of RAW264.7 cells. After being pretreated with oleuropein (10, 20, 40 μmol/L) for one hour, LPS induced inflammation model was established. Griess reagent was used to detect the release of nitrite in cells. Western blotting method was used to detect the expression of iNOS, COX-2, Nrf2, keap-1, HO-1 and NQO1 in cells. Flow cytometry was used to detect the expression of NO, ROS, and Ca2+ in cells. The levels of MMP, TNF-α and IL-6 in supernatant were detected by ELISA. Results Compared with model group, the release level of nitrite in the oleuroside group decreased significantly (P<0.05, 0.01, 0.001), the expression of iNOS and COX-2 decreased significantly (P<0.001), the production of NO decreased significantly (P<0.05, 0.01), the release of TNF-α and IL-6 was inhibited significantly (P<0.001), and the release of Ca2 + was inhibited significantly (P<0.01); ROS production was significantly inhibited (P<0.01); JC-1 monomer decreased, polymer state was restored (more red fluorescence), MMP stability was enhanced; Keap1 protein expression was significantly decreased, Nrf2, HO-1, NQO1 protein expression were significantly increased (P<0.05, 0.01 and 0.001). Conclusion Oleuropein has a significant inhibitory effect on LPS-induced RAW264.7 cells inflammatory response, which reduces the inflammatory process by activating the Nrf2/HO-1 signaling pathway.
[中图分类号]
R962.2
[基金项目]
国家青年科学自然基金项目(81803807);广西自治区青年科学基金项目(2018JJB140265);广西高校引进海外高层次人才“百人计划”项目(05018064);广西科技基地和人才专项(2018AD19034)。