Electroacupuncture at Auricular Vagus Nerve Inhibits 
Neuroinflammation in Rats with Cerebral Ischemia/
Reperfusion Injury via Downregulating the TLR4-Mediated 
NF-?B Signaling Pathway

Jiaen Yang; Zixuan Ou; Ning Jia; Jiaqi Feng

doi:10.70711/mhr.v3i1.9010

Electroacupuncture at Auricular Vagus Nerve Inhibits Neuroinflammation in Rats with Cerebral Ischemia/ Reperfusion Injury via Downregulating the TLR4-Mediated NF-?B Signaling Pathway

Jiaen Yang, Zixuan Ou, Ning Jia, Jiaqi Feng

Abstract

Objective: To explore the inhibitory effect of auricular vagus nerve electroacupuncture (VNS) on neuroinflammation in rats
with cerebral ischemia/reperfusion (I/R) injury and its association with the TLR4-mediated NF-?B signaling pathway. Methods: Seventytwo SPF-grade rats (220~250g) were randomly divided into control, sham operation, model (I/R), and electroacupuncture (VNS) groups
(18 rats each). The middle cerebral artery occlusion (MCAO) model was established by the Longa method. The VNS group received
electroacupuncture at the auricular concha region 30 minutes after ischemia, with continuous treatment for 4 days. Modified Neurological
Severity Score (mNSS) was used to evaluate neurological function at 24h and 72h post-surgery. At 72h, ELISA detected IL-1?, IL-6, and
TNF-? levels in the ischemic cortex; immunohistochemistry observed brain pathological damage; Western blot measured TLR4 and NF-
?B protein expressions. Results: Compared with the model group, the VNS group had significantly higher mNSS scores at 72h (P<0.001),
reduced pro-inflammatory factors (IL-1?, TNF-?), upregulated anti-inflammatory IL-6 (all P<0.001), alleviated brain pathological damage,
and downregulated TLR4 and NF-?B protein expressions (P<0.05). Conclusion: Auricular vagus nerve electroacupuncture inhibits neuroinflammation and improves neurological deficits in I/R rats by downregulating the TLR4-mediated NF-?B pathway, providing experimental evidence for ischemic stroke treatment.

Keywords

Auricular Vagus Nerve Stimulation; Cerebral Ischemia/Reperfusion Injury; TLR4; NF-?B Signaling Pathway

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DOI: http://dx.doi.org/10.70711/mhr.v3i1.9010

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