“通督调神”针刺对脑卒中后抑郁大鼠海马CREB/BDNF/TrkB信号通路的影响

Effect of Tongdu Tiaoshen acupuncture on CREB/BDNF/TrkB signaling pathway of hippocampus in rats with post-stroke depression

目的:观察“通督调神”针刺对脑卒中后抑郁(PSD)大鼠抑郁样行为以及海马环磷腺苷效应元件结合蛋白(CREB)/脑源性神经营养因子(BDNF)/酪氨酸蛋白激酶B(TrkB)通路的调节作用,探讨其改善PSD的可能机制。方法:将36只SPF级SD大鼠随机分为假手术组、模型组、通督调神组,每组12只。模型组、通督调神组大鼠采用Zea Longa线栓法和慢性不可预知性温和应激(CUMS)法复合制备PSD模型。通督调神组大鼠于造模结束后第4天予针刺“大椎”“水沟”“百会”“神庭”,每次干预40 min,每天1次,每周6次,连续干预4周。分别于PSD模型造模结束后第2天和干预4周后进行大鼠Zea Longa神经行为学评分、蔗糖水消耗实验和敞箱实验;生化法检测大鼠海马CA1区超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量;ELISA法检测大鼠血清BDNF含量;实时荧光定量PCR法检测大鼠海马CA1区BDNF、Trk B、CREB mRNA表达;Western blot法检测大鼠海马CA1区BDNF、Trk B、CREB,p-CREB蛋白表达。结果:与假手术组比较,造模后、干预后模型组及造模后通督调神组大鼠Zea Longa神经行为学评分升高(P<0.05),蔗糖水消耗百分比、敞箱实验水平与垂直运动评分降低(P<0.05)。与模型组比较,通督调神组大鼠干预后Zea Longa神经行为学评分降低(P<0.05),蔗糖水消耗百分比、敞箱实验水平与垂直运动评分升高(P<0.05)。与假手术组比较,模型组大鼠海马CA1区SOD、CAT活性及血清BDNF含量降低(P<0.05),MDA含量升高(P<0.05);与模型组比较,通督调神组大鼠海马CA1区SOD、CAT活性及血清BDNF含量升高(P<0.05),MDA含量降低(P<0.05)。与假手术组比较,模型组大鼠海马CA1区BDNF、TrkB、CREB mRNA及BDNF、TrkB、CREB、p-CREB蛋白表达降低(P<0.05);与模型组比较,通督调神组大鼠海马CA1区BDNF、TrkB、CREB mRNA及BDNF、Trk B、p-CREB蛋白表达、p-CREB/CREB比值升高(P<0.05)。结论:“通督调神”针刺可改善PSD大鼠抑郁样行为,其作用机制可能与抑制海马神经组织氧化应激,增强CREB/BDNF/Trk B信号通路活性有关。

Objective To observe the regulative effect of Tongdu Tiaoshen acupuncture on the depression-like behavior and cAMP-response element binding protein(CREB)/brain-derived neurotrophic factor(BDNF)/tyrosine protein kinase B(TrkB) signaling pathway of hippocampus in rats with post-stroke depression(PSD), and to explore its possible mechanism on improving PSD. Methods A total of 36 SPF SD rats were randomized into a sham operation group, a model group and a Tongdu Tiaoshen group, 12 rats in each group. The compound method of Zea Longa suture-occlusion and chronic unpredictable mild stress(CUMS) was used to establish the PSD model in rats of the model group and the Tongdu Tiaoshen group. On the 4th day after modeling, acupuncture was applied at "Dazhui"(GV 14), "Shuigou"(GV 26), "Baihui"(GV 20) and "Shenting"(GV 24) in the Tongdu Tiaoshen group, 40 min every time, once a day, 6 times a week for 4 weeks consecutively. On the 2nd day after PSD modeling and after 4-week intervention, Zea Longa neurobehavioral score was evaluated, sucrose water consumption test and open-field test were performed;biochemical method was used to detect the SOD, CAT activity and MDA level in hippocampal CA1 area;ELISA method was used to detect the serum level of BDNF;real-time PCR was used to detect the mRNA expression of BDNF, TrkB and CREB in hippocampal CA1 area;Western blot was used to detect the protein expression of BDNF, TrkB, CREB and p-CREB in hippocampal CA1 area. Results Compared with the sham operation group, Zea Longa neurobehavioral scores were increased(P<0.05), percentage of sucrose water consumption, horizontal motion and vertical motion scores of open-field test were decreased after modeling and intervention in the model group and after modeling in the Tongdu Tiaoshen group(P<0.05). Compared with the model group, Zea Longa neurobehavioral score was decreased(P<0.05), percentage of sucrose water consumption, horizontal motion and vertical motion scores of open-field test were increased after intervention in the Tongdu Tiaoshen group(P<0.05). Compared with the sham operation group, the SOD and CAT activity in hippocampal CA1 area and serum level of BDNF were decreased(P<0.05), MDA level in hippocampal CA1area was increased in the model group(P<0.05);compared with the model group, the SOD and CAT activity in hippocampal CA1 area and serum level of BDNF were increased(P<0.05), MDA level was decreased in the Tongdu Tiaoshen group(P<0.05). Compared with the sham operation group, the mRNA expression of BDNF, TrkB and CREB as well as the protein expression of BDNF, TrkB, CREB and p-CREB were decreased in hippocampal CA1 area in the model group(P<0.05);compared with the model group, the mRNA expression of BDNF, TrkB and CREB, the protein expression of BDNF, TrkB and p-CREB as well as the ratio of p-CREB/CREB were increased in the Tongdu Tiaoshen group(P<0.05). Conclusion Tongdu Tiaoshen acupuncture can improve the depression-like behavior in PSD rats, the mechanism may be related to the inhibition of oxidative stress in hippocampal tissues and the enhanced activity of CREB/BDNF/TrkB signaling pathway.