Electroacupuncture preconditioning alleviates cortical neuronal injury in cerebral ischemia-reperfusion by rebalancing HES1 and NF-κB expression

The roles of Hairy Enhancer of Split 1 (HES1) and nuclear factor kappa B (NF-κB) in neuronal injury following cerebral ischemia have been well established. However, the relationship between electroacupuncture preconditioning-induced neuroprotection and these signaling pathways remains unclear. This study aimed to investigate the effects of electroacupuncture pretreatment on the expression of HES1 and NF-κB in the cortex of rats subjected to cerebral ischemia/reperfusion and to explore the underlying mechanisms. A total of 36 male Sprague-Dawley rats were randomized into three groups: sham, model, and electroacupuncture pretreatment ( n = 12 per group). Cerebral ischemia/reperfusion was induced using the middle cerebral artery occlusion (MCAO) method. Rats in the electroacupuncture group received daily electroacupuncture stimulation at 'Baihui' and 'Dazhui' acupoints 1 week prior to MCAO. Neurological function scores, 2,3,5-triphenyltetrazolium chloride staining for cerebral infarction, Nissl staining for neuronal cell survival, and immunohistochemical detection of HES1 and NF-κB expression in the cerebral cortex were assessed. Compared to the sham group, the model group exhibited significant neurological deficits, extensive cerebral infarction, decreased neuronal survival, and increased expression of HES1 and NF-κB ( P < 0.01). In contrast, electroacupuncture pretreatment significantly improved neurological function scores ( P < 0.01), reduced cerebral infarction ( P < 0.01), increased neuronal survival ( P < 0.05), and decreased the expression of HES1 and NF-κB ( P < 0.01). These findings suggest that electroacupuncture preconditioning may mitigate brain injury in cerebral ischemia/reperfusion rats by downregulating the expression of HES1 and NF-κB, thereby reducing inflammatory damage and enhancing cerebral ischemia tolerance.