京尼平苷对β淀粉样蛋白诱导的神经细胞PC12凋亡的影响及相关机制研究

Effect of geniposide onβ-amyloid protein induced apoptosis of neuronal PC12 cells and related mechanism

目的探讨京尼平苷对β淀粉样蛋白(Aβ)诱导的神经细胞PC12凋亡的影响及相关作用机制。方法体外培养神经细胞PC12,以不同浓度梯度Aβ、京尼平苷作用于PC12,细胞计数试剂盒8(CCK-8)法检测其细胞活力。PC12分为对照组(不做任何处理)、Aβ组(32μmol/L Aβ)、京尼平苷组(32μmol/L Aβ+16μmol/L京尼平苷)和核因子E2相关因子2(Nrf2)抑制剂组(32μmol/L Aβ+16μmol/L京尼平苷+100 nmol/L鸦胆子苦醇),用CCK-8法和流式细胞仪分别检测PC12细胞活力和凋亡率;酶联免疫吸附法检测PC12细胞内活性氧、丙二醛和超氧化物歧化酶(SOD)含量;蛋白免疫印迹法检测PC12内Nrf2、血红素加氧酶1(HO-1)表达。结果与对照组比较,Aβ组PC12细胞活力及细胞内SOD、Nrf2、HO-1表达明显降低,凋亡率及细胞内活性氧、丙二醛含量明显升高,差异有统计学意义(P<0.05);与Aβ组比较,京尼平苷组PC12细胞活力及细胞内SOD、Nrf2、HO-1表达明显升高(P<0.05),凋亡率[(15.28±0.93)%vs(22.15±1.34)%,P<0.05]及细胞内活性氧[(1.58±0.22)U/ml vs(2.94±0.26)U/ml,P<0.05]、丙二醛[(5.04±0.78)μmol/ml vs(9.60±0.93)μmol/ml,P<0.05]含量明显降低;与京尼平苷组比较,Nrf2抑制剂组PC12细胞活力明显降低,差异有统计学意义[(60.23±5.56)%vs(89.68±5.72)%,P<0.05],凋亡率明显升高[(20.42±1.16)%vs(15.28±0.93)%,P<0.05]。结论京尼平苷对Aβ诱导的PC12细胞凋亡具有抑制作用,其机制可能与激活Nrf2/HO-1信号通路发挥抗氧化应激作用有关。

Objective To investigate the effect of geniposide onβ-amyloid protein(Aβ)-induced ap-optosis of neuronal PC12 cells and related mechanisms.Methods PC12 cells were treated with different concentration gradients of Aβand geniposide,and then cell viability was detected by cell counting kit 8(CCK-8)assay.PC12 cells were divided into control group(without any treat-ment),Aβgroup(32μmol/L Aβ),geniposide group(32μmol/L Aβ+16μmol/L geniposide)and nuclear factor erythroid 2 related factor 2(Nrf2)inhibitor group(32μmol/L Aβ+16μmol/L ge-niposide+100 nmol/L brusatol).CCK-8 assay and flow cytometry were used to detect cell viabili-ty and apoptosis,respectively;ELISA was applied to measure the contents of reactive oxygen spe-cies(ROS),malondialdehyde(MDA)and superoxide dismutase(SOD)in PC12 cells.Western blotting was employed to detect the expression of Nrf2 and heme oxygenase-1(HO-1)in PC12 cells.Results Compared with the control group,the cell viability and the levels of SOD,Nrf2 and HO-1 were significantly decreased,and the apoptotic rate and the contents of ROS and MDA were obviously increased in PC12 cells of the Aβgroup(P<0.05).The geniposide group had significantly enhanced cell vitality and expression levels of SOD,Nrf2 and HO-1(P<0.05),and lower apoptotic rate[(15.28±0.93)%vs(22.15±1.34)%,P<0.05]and contents of ROS[(1.58±0.22)U/ml vs(2.94±0.26)U/ml,P<0.05]and MDA[(5.04±0.78)μmol/ml vs(9.60±0.93)μmol/ml,P<0.05]than the Aβgroup.Cell viability was significantly decreased[(60.23±5.56)%vs(89.68±5.72)%,P<0.05],and apoptotic rate was notably increased[(20.42±1.16)%vs(15.28±0.93)%,P<0.05]in the Nrf2 inhibitor group when compared with the ge-niposide group.Conclusion Geniposide shows an inhibitory effect on Aβ-induced apoptosis of PC12 cells,and the mechanism may be related to its anti-oxidative stress effect by activation of Nrf2/HO-1 signaling pathway.