Electroacupuncture Regulates Hippocampal Synaptic Plasticity via Inhibiting Janus-Activated Kinase 2/Signal Transducer and Activator of Transcription 3 Signaling in Cerebral Ischemic Rats

Abstract

Objective: To determine the mechanism(s) involved in electroacupuncture (EA)-mediated improvements in synaptic plasticity in a rat model of middle cerebral artery occlusion and reperfusion (MCAO/R)-induced cognitive deficits. Methods: Focal cerebral ischemic stroke was induced by (MCAO/R) surgery. Rats were randomly split into 4 groups: control group (sham operation control), MCAO group, Baihui (GV 20) and Shenting (GV 24) acupoint EA group (verum acupuncture, MCAO + VA), and nonacupoint EA group (control acupuncture, MCAO + CA). EA treatment was administered for 14 consecutive days in MCAO + VA and MCAO + CA groups. Neurological assessment, behavioral performance testing, and molecular biology assays were used to evaluate the MCAO/R model, EA therapeutic effect and potential therapeutic mechanism(s) of EA. Results: Significant amelioration of neurological deficits was found in MCAO + VA rats compared with MCAO rats (P < .01). Moreover, learning and memory significantly improved in EA-treated rats compared with MCAO or MCAO + CA rats (P < .05) together with an increase in the number of PSD-95+ and SYN+ cells and synapses in the hippocampal CA1 region (P < .05). MCAO + VA rats also showed amelioration of pathological synaptic ultrastructural changes compared with MCAO or MCAO + CA groups (P < .001). In contrast, EA decreased the levels and phosphorylation of JAK2 (Janus-activated kinase 2) and STAT3 (signal transducer and activator of transcription 3) in the hippocampal CA1 region compared with MCAO or MCAO + CA group (P < .01). Conclusion: EA at GV 20 and GV 24 acupoints improved cognitive deficits in cerebral ischemic rats via the JAK2/STAT3 signaling pathway and mediated synaptic plasticity in the peri-infarct hippocampal CA1 region of rats following ischemic stroke.