异丙酚对肿瘤坏死因子-α诱导小鼠脊髓神经元凋亡的影响

Effects of propofol on apoptosis induced by TNF-αin mouse spinal cord neurons in vitro

目的研究异丙酚对肿瘤坏死因子-α(TNF-α)诱导小鼠脊髓神经元凋亡的影响。方法脊髓神经元取自孕14 d胎龄小鼠的胎鼠,于含B27的神经细胞培养基中培养7 d后,随机分为6组:对照组(Con组);50μmol／L异丙酚组(P50组);TNF-α组(TNF-α组);25μmol／L异丙酚+TNF-α组(P25+ TNF-α组);50μmol／L异丙酚+TNF-α组(P50+TNF-α组);100μmol／L异丙酚+TNF-α组(P100+TNF-α组),各组中加入相应终浓度的异丙酚孵育30 min,再加入TNF-α至终末浓度为2 000 U／ml,培养24 h后,采用碘化丙锭／Hoechst 33342双染法检测细胞凋亡,计算细胞凋亡率,采用免疫细胞化学方法测定Bcl-2表达。结果与Con组比较,TNF-α组神经元凋亡率升高,Bcl-2表达降低(P<0．01),不同浓度异丙酚预先给药可减弱TNF-α诱导的上述改变(P<0．05)。结论异丙酚可抑制TNF-α诱导小鼠脊髓神经元的凋亡,其机制与上调Bcl-2表达有关。

Objective To study the effects of propofol on apoptosis and Bcl-2 expression induced by TNF-α in cultured mouse spinal cord neurons. Methods Spinal cord neurons were enzymatically isolated from fetal mice and cultured in serum-free medium （neuronal basal ＋ B27）. On the 7th day the cultured neurons were randomly divided into 6 groups： group Ⅰ control; group Ⅱ propofol 50μmol·L^-1 ; group Ⅲ TNF-α; group Ⅳ, Ⅴ , Ⅵ propfol 25, 50, 100 μmol· L^- 1 ＋ TNF-α. Propofol was added to the cultured cells first and the cells were incubated for 30 min. Then TNF-α was added （the final concentration of TNF-α was 2 000 U·ml^-1 ） to the cells which were incubated for another 24 h. The apoptosis ratio was measured by using PI/Hoechst 33342 double staining technique. The Bcl-2 expression was determined by immuno-cytochemical technique. Results The apoptosis ratio was significantly increased and the Bcl-2 expression was significantly decreased in TNF-α group as compared with control group （ P 〈 0.01 ）. However pretreatment with different concentrations of propofol （25, 50, 100μmol·L^-1 ） significantly attennated the increase in apoptosis ratio and decrease in Bcl-2 expression induced by TNF-α. Conclusion Propofol can inhibit the apoptosis induced by TNF-α by modulating the Bcl-2 expression.