Electroacupuncture Ameliorates Cognitive Impairment and Regulates the Expression of Apoptosis-Related Genes Bcl-2 and Bax in rats with cerebral ischaemia-reperfusion injury

Abstract

Background Post-stroke cognitive impairment seriously affects the quality of life and functional rehabilitation of patients with stroke. Objective To examine the effects of electroacupuncture (EA) at GV20 and GV24 on cognitive impairment and apoptosis including expression of apoptosis-related genes Bcl-2 and Bax in a rat model of cerebral ischaemia-reperfusion (IR) induced by middle cerebral artery occlusion (MCAO). Methods Thirty-five Sprague-Dawley rats were allocated to a sham operation control group (SC group, n=10) or underwent surgery and MCAO (n=25). Postoperatively the latter group was randomly subdivided into EA or untreated (IR) groups. Cognitive impairment was assessed using the Morris water maze (MWM). Apoptosis was examined by detection of Bcl-2 and Bax expression in the cerebral cortex. Results The EA group had significantly decreased neurological deficit scores compared to the IR group (p<0.05). In the MWM test, significant differences in escape latency and route were observed between the EA and IR groups (p<0.05). Rats in the EA group performed better in the probe trial than those in the IR group (p<0.05). EA treatment markedly reduced the number of TUNEL-positive cells compared to the IR group (20.13±4.30% vs 38.40±3.38%; p<0.001). Reverse transcription-polymerase chain reaction (RT-PCR) results showed the Bcl-2/Bax ratio was significantly increased in the EA group compared to the IR group (1.61±0.19 vs 0.50±0.05, p<0.01). Conclusions These findings suggest that EA ameliorates cognitive impairment of rats with IR injury by modulating Bcl-2 and Bax expression.