奥氮平对鱼藤酮诱导PC12细胞凋亡的保护作用

探讨非典型抗精神病药物奥氮平对鱼藤酮诱导神经元凋亡的可能保护作用及其机制。以NGF诱导后的PC12细胞作为细胞模型,采用鱼藤酮诱导细胞凋亡。用不同浓度奥氮平、氟哌啶醇预处理后,观察鱼藤酮对PC12细胞的作用,分别用噻唑蓝(MTT)法检测细胞活性、流式细胞仪检测细胞凋亡率、Hoechst33342染色观察细胞形态学改变,并对二者的结果进行比较。鱼藤酮以剂量依赖的方式杀死PC12细胞。鱼藤酮(6μmol/L)作用后,奥氮平(50μmol/L)组预处理48h的细胞活力显著高于对照组(无药物预处理)(P<0.05);鱼藤酮(4、6、8μmol/L)作用后,氟哌啶醇组(20、40、60μmol/L)的细胞活力均低于对照组。流式细胞仪检测结果显示,对照组、氟哌啶醇(20μmol/L)组、奥氮平(50μmol/L)组、空白对照组(无药物预处理以及鱼藤酮处理)的细胞凋亡率依次为(32.2±1.3)%、(42.1±1.0)%、(14.0±1.0)%和(1.3±0.3)%。Hoechst33342染色结果显示,对照组每个视野多见凋亡细胞,细胞核裂解为碎块,氟哌啶醇组更明显;奥氮平组凋亡细胞数量较氟哌啶醇组及对照组为少。结果提示奥氮平对鱼藤酮诱导PC12细胞的凋亡具有保护作用,这可能是奥氮平和氟哌啶醇在精神分裂症病人应用中有不同的治疗效果和副作用的部分机制。

PROTECTIVE EFFECTS OF OLANZAPINE ON PC12 CELLS FROM ROTENONE INDUCED APOPTOSIS

To investigate the possible protective effects and underlying mechanisms of an atypical antipsychotic drug, olanzapine, on rotenone induced neuron apoptosis. Rotenone was used on NGF-differentiated PC12 cells to induce apoptosis. Cell viability was determined with MTT method, apoptotic cell ratio was detected with flow cytometer, and the apoptotic morphological change was examined with Hoechst33342 staining. The effects of olanzapine were compared with those of haloperidol treatment. Differentiated PC12 cells received a 48 h of incubation with olanzapine (at concentration of 50, 100 or 200 μmol/L, olanzapine group), haloperidol (at concentration of 20, 40 or 80 μmol/L, haloperidol group) or with culture medium followed with rotenone (4, 6, or 8 μmol/L) incubating for 24 h. Four groups were analyzed: olanzapine group (olanzapine + rotenone), haloperidol group (haloperidol+rotenone), control group (culture medium + rotenone) and blank control group (culture medium only). Olanzapine preincubation at concentration of 50 μmol/L (for 48 h) increased the cell viability after rotenone treatment at the concentration of 6 μmol/L (for 24 h)in vitro (P<0.05). Whereas olanzapine at 100 or 200 μmol/L rendered no significant effect on the cell viability (P>0.05). Cell viability of haloperidol treatment group, however, was lower than that in control group at each concentration (P<0.05). Apoptotic ratio, of control, haloperidol, olanzapine or blank control group was (32.2±1.3)%, (42.1±1.0)%, (14.0±1.0)% or (1.3±0.3)%, respectively. Most apoptotic cells which were characterized by nuclear fragmentation under Hoechst33342 staining were observed in control group and haloperidol group, especially the latter. Apoptotic cells were fewer in olanzapine group. The present results suggest that olanzapine have protective effects on NGF-differenti-ated PC12 cells from rotenone induced apoptosis. This may partly explain the different efficiencies and side effects of haloperidol and olanzapine in schizophrenia therapy.