Electro‑acupuncture ameliorates cognitive impairment via improvement of brain‑derived neurotropic factor‑mediated hippocampal synaptic plasticity in cerebral ischemia‑reperfusion injured rats

A previous study by our group found that electro‑acupuncture (EA) at the Shenting (DU24) and Baihui (DU20) acupoints ameliorates cognitive impairment in rats with cerebral ischemia‑reperfusion (I/R) injury. However, the precise mechanism of action has remained largely unknown. The present study investigated whether brain‑derived neurotropic factor (BDNF) mediates hippocampal synaptic plasticity as the underlying mechanism. Rats were randomly divided into three groups: The sham operation control (Sham) group, the focal cerebral ischemia‑reperfusion (I/R) group, and the I/R with EA treatment (I/R+EA) group. The I/R+EA group received EA treatment at the Shenting (DU24) and Baihui (DU20) acupoints after the operation. EA treatment was found to ameliorate neurological deficits (P<0.05) and reduce the cerebral infarct volume (P<0.01). In addition, EA improved cognitive function in cerebral I/R‑injured rats (P<0.05). Furthermore, EA treatment promoted synaptic plasticity. Simultaneously, EA increased the hippocampal expression of BDNF, its high‑affinity tropomyosin receptor kinase B (TrkB) and post‑synaptic density protein‑95 (PSD‑95) in the rats with cerebral I/R injury. Collectively, the findings suggested that BDNF‑mediated hippocampal synaptic plasticity may be one mechanism via which EA treatment at the Shenting (DU24) and Baihui (DU20) acupoints improves cognitive function in cerebral I/R injured rats.