Electroacupuncture regulates the stress-injury-repair chain of events after cerebral ischemia/reperfusion injury

Abstract

Inflammation after stroke is the main cause of cerebral ischemia/reperfusion injury. Cascading events after injury can lead to cell death. Heat shock protein 70 and other endogenous injury-signaling molecules are released by damaged cells, which can lead to systemic stress reactions. Protecting the brain through repair begins with the stress-injury-repair signaling chain. This study aimed to verify whether acupuncture acts through this chain to facilitate effective treatment of ischemic stroke. Rat models of cerebral ischemia/reperfusion injury were established by Zea Longa's method, and injury sites were identified by assessing neurological function, 2,3,5-triphenyltetrazolium chloride staining, and hematoxylin-eosin staining. Electroacupuncture at acupoints Baihui (DU20) and Zusanli (ST36) was performed in the model rats with dilatational waves, delivered for 20 minutes a day at 2–100 Hz and an amplitude of 2 mA. We analyzed the blood serum from the rats and found that inflammatory cytokines affected the levels of adrenotrophin and heat shock protein 70, each of which followed a similar bimodal curve. Specifically, electroacupuncture lowered the peak levels of adrenocorticotrophic hormone and heat shock protein 70. Thus, electroacupuncture was able to inhibit excessive stress, reduce inflammation, and promote the repair of neurons, which facilitated healing of ischemic stroke.

Keywords

• nerve regeneration; electroacupuncture; cerebral ischemia/reperfusion; inflammation; adrenocorticotrophic hormone; heat shock protein 70; Baihui (DU20); Zusanli (ST36); neural regeneration