基于TLR-4/MyD88/NF-κB通路探讨针刺改善血管性痴呆大鼠认知功能的机制

Acupuncture Improve Scognitive Function of Vascular Dementia Rats byRegulating TLR-4/MyD88/NF-κB Pathway

目的研究针刺通过调控Toll样受体4(TLR-4)/髓样分化因子88(MyD88)/核因子κB(NF-κB)信号通路改善血管性痴呆大鼠认知功能的机制。方法将36只SPF级SD雄性大鼠采用随机数表法分成假手术组(A组)、模型组(B组)和针刺组(C组),每组12只。B组和C组采用改良两血管结扎法制备血管性痴呆模型,A组仅手术分离双侧颈总动脉、不结扎。C组采用针刺“百会”“肾俞”“丰隆”穴进行干预,每个疗程6天,共2个疗程;A组、B组正常喂养,不进行干预。每组大鼠进行Morris水迷宫实验,评估其学习记忆能力;ELISA测定大鼠血清IL-1β、TNF-α水平;Real-time PCR测定海马TLR-4、MyD88、NF-κB mRNA的表达;免疫组化测定大脑Iba1、NF-κB蛋白的阳性表达;Western blot测定海马IL-1β、TNF-α相对表达水平。结果与B组相比,C组大鼠逃避潜伏期缩短(P<0.01),穿越平台次数增多(P<0.05);血清中TNF-α、IL-1β浓度明显降低(P<0.01);海马中TLR-4、MyD88、NF-κB mRNA的表达量明显减少(P<0.01);大脑的Iba1、NF-κB蛋白的阳性表达明显减少(P<0.01);海马中的TNF-α、IL-1β相对表达量明显减少(P<0.01)。结论针刺“百会”“肾俞”“丰隆”穴可以改善血管性痴呆大鼠的认知功能障碍,其机制可能与通过抑制TLR-4/MyD88/NF-κB信号通路活性,从而抑制神经炎性反应有关。

Objective To study the effect of acupuncture on the effect of acupuncture on the learning and memory ability and inflammatory factor expression in rats with vascular dementia,to provides an experimental basis for acupuncture and treatment of vascular dementia.Methods Randomly dividing thirty-six SPF grade SD male rats into 12 rats in sham surgery(A),model(B),and acupuncture(C).Groups B and C will prepare the VD model,and Group A will only surgically isolated the bilateral common carotid arteries without ligation.In Group C,acupuncture with"Baihui","Shenshu"and"Fenglong"points were used for intervention,each course lasts for 6 days,for a total of 2 sessions;Group A and Group B were fed normally without intervention.Morris water maze experiment was used to assess spatial learning and memory,ELISA for serum IL-1βand TNF-α,Real-time PCR for TLR-4,MyD88 and NF-κB mRNA,positive expression of Iba1 and NF-κB,and Western blot for relative expression levels of IL-1βand TNF-αin hippocampus.Results Compared with group B,group C rats had a shorter escape latency period(P<0.01)and had crossed the platform more often(P<0.05);The serum concentrations of TNF-αand IL-1βwere significantly decreased(P<0.01);The expression amount of mRNA of TLR-4/MyD88/NF-κB was significantly reduced in the hippocampus(P<0.01);The positive expression of Iba1 and NF-κB protein in the brain was significantly reduced(P<0.01);The relative expression level of TNF-αand IL-1βin the hippocampus was significantly reduced(P<0.01).Conclusion Needle"Baihui","Shenshu"and"Fenglong"can improve vascular dementia rats cognitive dysfunction,and the mechanism may be related to the inhibition of neuroinflammatory response by inhibiting TLR-4/MyD88/NF-κB signaling pathway activity.