Effects Of Electroacupuncture On Hippocampal C3-C3aR-STAT3 Signal In SAMP8 Mice

Objective To observe the effects of electroacupuncture(EA)on synaptic function and C3-C3 a R-STAT3 signaling in the hippocampus of SAMP8 mice.To explore the mechanism of EA in improving Alzheimer’s disease(AD)synaptic dysfunction from the perspective of complement,and enrich the experimental and theoretical basis of EA in the treatment of AD.MethodsTwenty-four 6-month-old male SAMP8 mice were divided into model group(n=12)and EA group(n=12)by random number table method,and the same age SAMR1 mice were as control group(n=12).Each day from 15:00 p.m.to 17:00 p.m.,the same person fixed the EA group mice on the board with self-made rope net pocket for EA intervention.DU 20,DU 14 and BL 23 were selected in the EA group,EA positive pole connected DU 14 points,negative pole connected BL 23 points(alternated on both sides),continuous-wave stimulation were selected at a frequency of 2 Hz(intensity 1.5-2 m A).An individual EA session was administered daily for 20 min,8 days as a course of treatment,and there were 3 courses of treatment with 2 days between each course of treatment.Mice in model group and control group were fixed for the same length of time as that in EA group.Learning and memory ability was assessed using Morris Water Maze test.Then,immunofluorescence analysis for the hippocampal CA1 region of mice:(1)Co-localization of astrocyte marker GFAP and C3.(2)Co-localization of microglia marker Iba1 with C3 a R.Western blot was used to detect protein expression of Syn,PSD-95,C3,C3 a R,STAT3 and p-STAT3.The real-time fluorescent quantitative PCR was used to detect the m RNA level of C3,C3 a R,STAT3.ResultsExperiment one: effect of EA on the learning ability of SAMP8 miceMWM: compared with the normal group,the escape latency was increased in the model group(P<0.01),the time staying in the quadrant of the platform decreased(P<0.01),as well as the number passing the original platform(P<0.01).Compared with the the model group,the average escape latency of mice in the EA group was significantly shorter(P<0.05),the time staying in the quadrant of the platform increased(P<0.05),as well as the number passing the original platform(P<0.05).Experiment two: effect of EA on synaptic function in SAMP8 miceWestern blot: compared with the normal group,the protein expression of Syn,PSD-95 were reduced(P<0.01).Compared with the the model group,the number of the EA group was reduced(P<0.01).Experiment three: effect of EA on C3-C3 a R-STAT3 signaling in SAMP8 mice1.Immunofluorescence: compared with the normal group,the number of positive indicators of co-located with GFAP and C3,Iba1 and Ca3 R increased significantly in the model group(P<0.01).Compared with the the model group,the number of the EA group was reduced(P<0.01).2.Western blot: compared with the normal group,the protein expression of C3,C3 a R,STAT3 and p-STAT3 in model group was significantly increased(P<0.01).Compared with the the model group,the protein expression of C3,C3 a R,STAT3 and p-STAT3 in EA group was reduced in the hippocampus(P<0.05).3.qPCR: compared with the normal group,the gene expression of C3,C3 a R,STAT3 in model group was significantly increased(P<0.01).Compared with the the model group,the gene expression were reduced(P<0.01).Conclusions1.EA can strengthen the learning and memory ability of the SAMP8 mice.2.EA can improve synapse-related protein expression and improve synaptic function in SAMP8 mice.3.EA can inhibit the C3-C3 a R-STAT3 signal in the hippocampus of SAMP8 mice.