Electroacupuncture decreases cognitive impairment and promotes neurogenesis in the APP/PS1 transgenic mice.

BACKGROUND: Alzheimer's disease (AD) is a severe neurodegenerative disease for which there is currently no effective treatment. The purpose of this study was to investigate whether repeated electroacupuncture (EA) stimulation would improve cognitive function and the pathological features of AD in amyloid precursor protein (APP)/presenilin 1 (PS1) double transgenic mice. METHODS: Cognitive function of APP/PS1 double transgenic mice was assessed using the Morris water maze test before and after EA treatment. Levels of amyloid ß-peptide (Aß) deposits in the hippocampus and cortex were evaluated by immunofluorescence, western blot and enzyme-linked immunosorbent assay. Expression of brain-derived neurotrophic factor (BDNF) was also examined by immunofluorescence and western blot. The neurogenesis was labeled by the DNA marker bromodeoxyuridine. RESULTS: EA stimulation significantly ameliorated the learning and memory deficits of AD mice by shortening escape latency and increasing the time spent in the target zone during the probe test. Additionally, decreased Aß deposits and increased BDNF expression and neurogenesis in the hippocampus and cortex of EA-treated AD mice were detected. The same change was detected in wild-type mice after EA treatment compared with wild-type mice without EA treatment. CONCLUSIONS: Repeated EA stimulation may improve cognitive function, attenuate Aß deposits, up-regulate the expression of BDNF and promote neurogenesis in the APP/PS1 double transgenic mice. This suggests that EA may be a promising treatment for AD.

Electroacupuncture pretreatment attenuates cerebral ischemic injury through α7 nicotinic acetylcholine receptor-mediated inhibition of high-mobility group box 1 release in rats.

BACKGROUND: We have previously reported that electroacupuncture (EA) pretreatment induced tolerance against cerebral ischemic injury, but the mechanisms underlying this effect of EA are unknown. In this study, we assessed the effect of EA pretreatment on the expression of α7 nicotinic acetylcholine receptors (α7nAChR), using the ischemia-reperfusion model of focal cerebral ischemia in rats. Further, we investigated the role of high mobility group box 1 (HMGB1) in neuroprotection mediated by the α7nAChR and EA. METHODS: Rats were treated with EA at the acupoint "Baihui (GV 20)" 24 h before focal cerebral ischemia which was induced for 120 min by middle cerebral artery occlusion. Neurobehavioral scores, infarction volumes, neuronal apoptosis, and HMGB1 levels were evaluated after reperfusion. The α7nAChR agonist PHA-543613 and the antagonist α-bungarotoxin (α-BGT) were used to investigate the role of the α7nAChR in mediating neuroprotective effects. The roles of the α7nAChR and HMGB1 release in neuroprotection were further tested in neuronal cultures exposed to oxygen and glucose deprivation (OGD). RESULTS: Our results showed that the expression of α7nAChR was significantly decreased after reperfusion. EA pretreatment prevented the reduction in neuronal expression of α7nAChR after reperfusion in the ischemic penumbra. Pretreatment with PHA-543613 afforded neuroprotective effects against ischemic damage. Moreover, EA pretreatment reduced infarct volume, improved neurological outcome, inhibited neuronal apoptosis and HMGB1 release following reperfusion, and the beneficial effects were attenuated by α-BGT. The HMGB1 levels in plasma and the penumbral brain tissue were correlated with the number of apoptotic neurons in the ischemic penumbra. Furthermore, OGD in cultured neurons triggered HMGB1 release into the culture medium, and this effect was efficiently suppressed by PHA-543,613. Pretreatment with α-BGT reversed the inhibitory effect of PHA-543,613 on HMGB1 release. CONCLUSION: These data demonstrate that EA pretreatment strongly protects the brain against transient cerebral ischemic injury, and inhibits HMGB1 release through α7nAChR activation in rats. These findings suggest the novel potential for stroke interventions harnessing the anti-inflammatory effects of α7nAChR activation, through acupuncture or pharmacological strategies.

[Involvement of cerebral neuroglobin in electroacupuncture preconditioning-induced protection effect in cerebral ischemia-reperfusion rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on cerebral ischemia and the role of cerebral neuroglobin (NgB) in EA-induced brain protection in focal cerebral ischemia and reperfusion injury (CI/RI) rats. METHODS: Male SD rats were randomly assigned to sham control, CI/RI 6 h, CI/RI 24 h and CI/RI 72 h groups (n = 6) for observing changes of NgB at different time-points. Additional SD rats were randomly assigned to sham, model, and EA preconditioning (EA-PC) groups (n = 16) for observing changes of cerebral NgB positive cell counts in the ischemic penumbra region 24 h after reperfusion. EA pre-conditioning was applied to "Baihui" (GV 20) for 30 min, once daily for 5 days before CI/RI. CI/RI model was established by occlusion of the right middle cerebral artery and reperfusion for 6 h, 24 h and 72 h respectively. The neurological behavior scores (NBS) of all the rats were evaluated according to Garcia's methods. The cerebral infarct volume was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining. The number of cerebral NgB positive cells was detected by immunofluorescent staining. RESULTS: No infarct loci were found in the sham group. The cerebral infarction volume percentage was significantly higher in the model group than in the EA-PC group (P < 0.01), while the NBS was significantly lower in the model group than in the EA-PC group (P < 0.01). The number of cerebral NgB positive cells in the ischemic penumbra was up-regulated 6 h after CI/RI injury, peaked at 24 h and continued at 72 h. Compared with the sham group, the number of cerebral NgB positive cells of the model group was increased significantly, whereas that of the EA-PC group up-regulated further obviously in comparison with the model group (P < 0.01). CONCLUSION: EA pretreatment has a significant neuroprotective effect on cerebral ischemia-reperfusion, which is closely related to its effect in up-regulating NgB protein expression.