电针调控CASP-1/GSDMD细胞焦亡信号通路对抑郁症小鼠干预机制

The intervention mechanism of electroacupuncture on CASP-1/GSDMD pyroptosis signaling pathway in depressed mice

目的:观察电针干预对抑郁症模型小鼠行为学、CASP-1/GSDMD细胞焦亡信号通路相关蛋白及海马突触可塑性的影响,探讨早期电针干预抑郁症的效应及其机制。方法:健康C57BL/6小鼠随机分成四组:空白组、模型组、氟西汀、电针组,每组8只。除空白组外,其余各组均腹腔注射利血平构建急性抑郁小鼠模型。电针组取百会、内关给予电针干预,每次20 min,1次/d,连续7 d。通过悬尾实验、强迫游泳实验对各组小鼠进行行为学评价,蛋白印迹法(Western blot)、高尔基染色(Golgi-Cox staining)、免疫荧光(IF)法检测各组小鼠海马CASP-1/GSDMD细胞焦亡信号通路相关蛋白及海马突触可塑性的变化。结果:与空白组相比,模型组小鼠悬尾和强迫游泳实验中不动时间明显增加(P<0.001),小鼠海马CA1区树突棘密度显著减少(P<0.001),小鼠海马组织中CASP-1/GSDMD信号通路相关蛋白NLRP3、CASP-1、IL-1β表达水平显著增加(P<0.001),小鼠海马区小胶质细胞标志物Iba-1表达显著增加(P<0.001)。与模型组比较,电针组小鼠悬尾和强迫游泳实验中不动时间明显缩短(P<0.001),小鼠海马CA1区树突棘密度明显增加(P<0.001),小鼠海马组织中CASP-1/GSDMD信号通路相关蛋白NLRP3、CASP-1、IL-1β表达水平显著下降(P<0.001),小鼠海马区小胶质细胞标志物Iba-1表达显著减少(P<0.001)。结论:电针干预可缓解利血平诱导的抑郁样行为,其机制可能与电针干预抑制CASP-1/GSDMD细胞焦亡信号通路及改善突触可塑性有关。

Objective:To observe the effects of electroacupuncture intervention on the behavior of depression model mice,the proteins related to the pyroptosis pathway of CASP-1/GSDMD and the plasticity of hippocampal synapses,and to explore the effects of early electroacupuncture intervention on depression and its mechanism.Methods:Healthy C57BL/6 mice were randomly divided into four groups:control,model,fluoxetine group and electroacupuncture group,with 8 mice in each group.Except control group,reserpine was injected intraperitoneally to establish acute depression mouse model.In the electroacupuncture group,“Baihui”and“Neiguan”were given electroacupuncture intervention,20 min each time,for consecutive 7 days.The tail suspension test,forced swimming test were used to evaluate the behavior of mice in each group.Western blot,Golgi-Cox staining,immunofluorescence staining method was used to detect the changes of proteins related to the signaling pathway of CASP-1/GSDMD pyroptosis and the synaptic plasticity of hippocampus.Results:Compared with control group,immobility time in tail suspension and forced swimming was significantly increased in model group(P<0.001),the density of dendritic spines in hippocampal CA1 region of mice was significantly decreased(P<0.001),the expression levels of CASP-1/GSDMD signaling pathway related proteins NLRP3,CASP-1,IL-1βin mouse hippocampus were significantly increased(P<0.001),the expression of microglial marker Iba-1 in the hippocampus of mice was significantly increased(P<0.001).Compared with the model group,the immobility time of the electroacupuncture group was significantly shorter in tail suspension and forced swimming(P<0.001),the density of dendritic spines in hippocampal CA1 region was significantly increased(P<0.001),the expression levels of CASP-1/GSDMD signaling pathway related proteins NLRP3,CASP-1,IL-1βin mouse hippocampus were significantly decreased(P<0.001),the expression of microglial marker Iba-1 in the hippocampus of mice was significantly decreased(P<0.001).Conclusion:Electroacupuncture intervention can alleviate depression-like behavior induced by reserpine,and the mechanism may be related to the inhibition of CASP-1/GSDMD pyroptosis signaling pathway and the improvement of synaptic plasticity.