硒代蛋氨酸对Aβ_(1-42)诱导N2a细胞损伤的保护作用

Neuroprotective Effect of Selenomethionine Against Injury Induced by Aβ_(1-42) in N2a Cells

探索硒代蛋氨酸(Se-Met)的早期干预对Aβ1-42诱导的Neuro-2A(N2a)细胞损伤的保护作用。将N2a细胞分为对照组、Aβ1-42诱导损伤组、Se-Met组和Se-Met预处理的Aβ1-42组,CCK-8法检测显示不同浓度Se-Met对N2a细胞活力的影响不同,且Se-Met能减弱Aβ1-42诱导N2a细胞活力的降低(P<0.01);DCFH-DA标记检测可见Se-Met预处理明显抑制Aβ1-42引起的N2a细胞内总活性氧(reactive oxygen species,ROS)水平增高,Aβ1-42作用24 h组效果更显著(P<0.05);Western blot检测发现,Se-Met可显著回升Aβ1-42引起的N2a细胞synaptophysin和PSD95水平的降低(P<0.05;P<0.05);同时,Se-Met可显著降低Aβ1-42引起的N2a细胞内LC3-II/LC3-I水平的升高(P<0.05)。因此,Se-Met在一定作用时间和浓度下可以提高N2a细胞的活力,对Aβ1-42引起的N2a细胞ROS水平增高、自噬均有抑制作用,同时缓解Aβ1-42引起的突触损伤;Se-Met对Aβ1-42诱导N2a细胞损伤具有较好的保护作用。

To investigate the effect of Selenomethionine （Se-Met） on amyloid beta peptide （Aβ）1-42）-induced neurotoxicity in Neuro-2A （N2a） cells, N2a cells were divided into 4 subgroups： control, Aβ1-42 model, Se-Mettreated and Se-Met-preincubated Aβ1-42 model group. Cell viability was evaluated by CCK-8 kit and the result showed that different concentrations of Se-Met had different effect on N2a cell viability. Aβ1-42 treatment significantly decreased cell viability compared to the control group, while Se-Met preincubation attenuated Aβ1-42induced cell viability loss （P〈0.05）. Levels of ROS （reactive oxygen species） were measured by DCFH-DA probe kit. Pretreatment with Se-Met significantly decreased the level of ROS in Aβ1-42 treated cells （P〈0.05）. Meanwhile, Se-Met pretreatment significantly restored the levels of synaptophysin and PSD95 and inhibited Aβ1-42-induced increase in the level of LC3-IULC3-I （P〈0.05）. These data suggested that Se-Met could increase N2a cell viability at a certain concentration and a period of time, inhibit the increase of ROS generation and autophagy, and ameliorate the synaptic loss induced by Aβ1-42. Thus, Se-Met plays an important role in neuroprotection of Aβ-induced neuronal toxicity.