对药酸枣仁-合欢花对抑郁模型大鼠行为学及皮质ERK-CREB细胞信号转导通路的影响

目的探讨对药酸枣仁-合欢花对抑郁模型大鼠行为学及皮质细胞外信号调节蛋白激酶(ERK)-环磷腺苷反应元件结合蛋白(CREB)细胞信号传导通路的影响。方法将雄性2月龄SD大鼠75只,按随机数字表法分为正常组、模型组、中药组、西药组、PD184161组,每组15只。采用孤养加慢性不可预知性温和应激(CUMS)复制大鼠抑郁模型,于实验前1d及实验第1、2、3周末用旷场实验、糖水消耗实验观察各组大鼠的行为学改变。采用实时荧光定量聚合酶链式反应(Real-Time PCR)法对皮质CREB、BDNF mRNA行定量分析。蛋白质免疫印迹(Western Blot)法测皮质ERK1/2、p-ERK1/2、p-RSK及p-CREB蛋白表达水平。结果与正常组比较,模型组大鼠旷场实验得分、糖水消耗度下降,从第2周末开始有统计学意义(P<0.05,P<0.01)、皮质CREB、BDNF mRNA水平下降(P<0.05,P<0.01)、ERK1/2、p-ERK1/2、p-RSK、p-CREB蛋白表达降低(P<0.05,P<0.01);与模型组比较,中药组、西药组、PD184161组大鼠旷场实验得分、糖水消耗度提高,从第2周末开始有统计学意义(P<0.05,P<0.01),皮质CREB、BDNF mRNA水平上调(P<0.05),ERK、p-ERK、p-RSK、p-CREB蛋白表达增强(P<0.05,P<0.01);与中药组比较,PD184161组大鼠旷场实验得分、糖水消耗度下降,第3周末有统计学意义(P<0.05),皮质CREB、BDNF mRNA水平下降(P<0.05),ERK、p-ERK、p-RSK、p-CREB蛋白表达降低(P<0.05)。结论对药酸枣仁-合欢花能够改善抑郁模型大鼠的抑郁症状,具有抗抑郁功效,其作用机制可能与激活ERK-CREB信号传导通路,增强通路中关键因子的表达有关。

Effects of Herbal Pair of Ziziphi spinosae Semen and Albiziae Flos on Behavior and Cellular Signal Transduction Pathway of ERK-CREB in Cortex of Depression Model Rats

Objective To investigate the effect of herbal pair of Ziziphi spinosae semen and Albiziae flos on the behavior of depression model rats and the signal pathway of extracellular signal-regulated protein kinase(ERK)-cyclicamp response element binding protein(CREB) in cortex of rats.Methods Seventy-five 2-month-old SD rats were randomly divided into five groups:normal group,model group,traditional Chinese medicine group,western medicine group and PD 184161 group,with 15 rats in each group.Depression rats were induced by chronic unpredictable mild stress(CUMS) in solitary culture.Behavioral changes of rats in each group were observed by open field test and sugar and water consumption one day before the experiment,and first,second and third weekends of the experiment.Real-time fluorescence quantitative polymerase chains reaction(Real-time PCR) was used to quantitatively analyze the mRNA expression of CREB and BDNF in hippocampus.The expressions of ERK,pERK,p-RSK and p-CREB in cortex were detected by immunohistochemistry.Results Compared with the normal group,the scores of open field test and the consumption of sugar and water in model group rats decreased.Statistical significant difference was observed from the 2nd weekend(P<0.05,P<0.01).The levels of CREB mRNA and BDNF mRNA in cortex decreased(P<0.05,P<0.01),and the expressions of ERK,p-ERK,p-RSK and pCREB protein decreased(P<0.05,P<0.01).Compared with the model group,the scores of open field test and the consumption of sugar and water were increased in the traditional Chinese medicine group,western medicine group and PD 184161 group rats and statistical significance was shown from the 2 nd weekend(P<0.05,P<0.01).The levels of CREB mRNA and BDNF mRNA in cortex were up-regulated(P<0.05),and the expressions of ERK,pERK,p-RSK and p-CREB protein were increased(P<0.05,P<0.01).Compared with the traditional Chinese medicine group,the scores of open field test and the consumption of sugar and water in PD 184161 group decreased with statistical significance from the 3nd weekend(P<0.05).The levels of CREB mRNA and BDNF mRNA in cortex decreased(P<0.05),and the expression of ERK,p-ERK,p-RSK and p-CREB proteins decreased(P<0.05).Conclusion The herbal pair of Ziziphi spinosae semen and Albiziae flos showed antidepressant effect,and the mechanism may be related to activating ERK-CREB signal transduction pathway and enhancing the expression of key factors in the pathway.